MXPA01001309A - Seedless tomato and method for producing seedless tomato and hybrid tomato plants capable of producing said seedless tomatoes - Google Patents

Abstract

The invention relates to a method for producing a seedless tomato, a plant carrying seedless tomatoes or capable of carrying seedless tomatoes, or cultivation material for such a tomato plant such as seed, comprising the steps of:a) providing a first tomato plant that contains the pk, fs-complex;b) providing a second tomato plant that contains the pk,fs-complex;c) crossing the first and second tomato plant for the production of cultivation material, such as seed, which contains pk,fs-complex;d) optionally cultivating the cultivation material thus obtained into a tomato plant capable of carrying seedless tomatoes;e) optionally growing said tomato plant until it carries the seedless tomatoes, and harvesting the seedless tomatoes thus obtained. The invention also relates to a hybrid tomato plant capable of carrying seedless tomatoes, obtained via said method, to seed or cultivating material for such a hybrid tomato plant, to a seedless tomato, obtained as fruit from such a hybrid tomato plant. Furthermore, the invention relates to processed products, in particular processed food products, obtained from or using, or containing , such a seedless tomato.

Description

TOMATO WITHOUT SEED AND METHOD FOR THE PRODUCTION OF TOMATO WITHOUT SEED AND HYBRID TOMATO PLANTS ABLE TO PRODUCE SUCH TOMATOES WITHOUT SEED DESCRIPTION OF THE INVENTION The present invention relates to a seedless tomato, a method for obtaining tomato without seed, as well as a method for processing the tomato without semi-11.a obtained in this way, for products, in particular food products. WO 98/24301 in the name of the applicant describes a seedless tomato and a method for the production of said tomato, in which a first tomato plant that is homozygous recessive with respect to parthenocarpy (pk, pk) and sterility properties functional (fs, fs) is crossed with a second plant that is also homozygous recessive with respect to the properties of parthenocarpy (pk, pk) and functional sterility (fs, fs). The present invention represents an improvement over the teaching of WO 98/24301, since it provides hybrids (and seed for them) that allow reliable production of Ref: 127162 seedless tomatoes under all environmental conditions, including different light and temperature conditions as they may be prevalent in the tropics, as well as in moderate climates. This is necessary in order to provide hybrids and seeds for them that can be successfully marketed and developed in all countries of the world, including countries that start to grow tomatoes such as those in the Far East. H. Georgiev et al., Eucarpia Tomato-90, Proceedings of the XI Eucarpia Meeting on Tomato Genetics and Breeding, Malaga, Spain, March 1990: "Breeding of Seddless Tomatoes" describe a method to obtain tomato plants that carry tomato fruits completely seedless, combining in a culture the genes homozygous for the parthenocarpy pat-2 and the homozygous gene for the self-sterility of the flowers ps-2. The pat-2, ps-2 crop obtained in this way has completely seedless tomato fruits (as shown in Tables 1 and 2 of the Georgiev reference). Georgiev et al. Further describe that by crossing two such crops, Fl hybrids can be created which have completely seedless fruits and standards.

However, the extensive research by the applicant on the line (s) described by Georgiev has shown that when the property of the parthenocarpy and the property of self-sterility are combined to provide progenitor lines, and the hybrid seed is obtained at from two of these parent lines-for example by means of human intervention as described below-that the presence only of the double-recessive pat-2 gene and only the double-recessive ps-2 gene is in practice insufficient to provide hybrids that they will stably and reliably form seedless tomatoes under all development conditions. Therefore, the crossing of two progenitor lines containing both only the double recessive genes (pa t-2, pa t-2) and (ps-2, ps-2) will not lead to commercially acceptable seedless hybrids, since plants will not always, and not under all circumstances, provide well-formed tomatoes. According to the present invention, it has been found that in order to provide hybrids that produce seedless tomatoes in a stable and reliable manner under all environmental conditions, a complex of genetic factors for parthenocarpy and for self-sterility must be present in the progenitor plants or in the progenitor lines. These complexes are referred to herein as the "pk complex" and the "fs complex", respectively. The applicant has also developed a general method for obtaining progenitor plants or progenitor lines containing this pk complex and fs complex, starting from known lines that only contain the double recessive pat-2 gene or the double recessive ps-2 gene, or starting from the line pat-2, ps-2 developed by Georgiev, described above. One step of this method may involve crossing a line with no known seed, such as the line pa t-2, ps-2 of Georgiev with a tomato plant with seed known per se, in order to provide a line Fl with seed. From this Fl, after several subsequent generations, the progenitor plants or lines can then be developed, in which the pk complex and the fs complex have been sufficiently "fixed" for these plants, to be used as progenitor lines for the production of hybrid seed.

In doing so, the applicant has found that in generations derived from Fl, the inheritance of the seedless phenotype (and even the phenotype of functional sterility) does not conform to what was expected based on Mendelian principles. In particular, the applicant has surprisingly found that, even when a tomato line with the seedless phenotype due to the presence of the recessive doubles pat-2 and ps-2 genes (such as the line described by Georgiev) is used as the initial material, in the F2 obtained by self-pollination of the Fl thus obtained, seedless plants are in fact very rare (for example, limited to approximately 1 or 2 plants of 100 F2 plants) or may not even appear at all, and may then not even occur when the functionally sterile plants from F2 obtained in this way, are self-pollinated to provide an F3. This is surprising because, based on the fact that in the parent pa t-2, original ps-2, the presence of the double-recessive genotype pat-2 and ps-2 is sufficient to provide a desired seedless phenotype, it was expected based on the Mendelian rules that at least one of 16 plants of said F2 (and even more plants in the subsequent F3) could have the double recessive genotype pat-2, ps-2 and therefore show the seedless phenotype . In practice, many fewer or even no seedless plants are found in F2 (and F3). However, despite the fact that F2 shows fewer plants with the desired seedless phenotype than what was expected - or in other words, despite the fact that the crossing of the line pa t-2, ps- 2 with a line of tomato with seed apparently introduces genes, alleles and / or other genetic factors that reduce or suppress the desired property of the lack of seed in F2, or at least the complete expression of the genes pat-2 and / or ps -2- it has been found that starting from an F2, the seedless progenitor lines can be developed, which provide seedless hybrids that are superior to those that can be obtained using the seedless progenitor lines, known, with the genotype pat-2, ps-2. The foregoing (also) demonstrates the basic finding of the invention, for example, that in order to stably and reliably provide hybrids that give seedless tomatoes under all environmental conditions, the presence of the pat-2 genotype, ps- 2 by itself, is not enough, but in fact a complex of genes, alleles or other genetic factors for parthenocarpy and for self-sterility must be present. In addition to this, the applicant has also found that some plants or lines of tomato with seed, when crossed with a line without known seed, are more likely to provide seedless progenitor lines, satisfactory than others, and in larger numbers. The present disclosure will therefore also teach the person skilled in the art how to select from all tomato lines known per se - by means of a simple procedure - those plants or lines that can be used successfully to provide progenitor lines for the production of seedless hybrids. The present description will also provide the skilled person with some guidance on the selection of such seed lines, based on the experience obtained by the applicant in the course of this investigation. The invention therefore provides a method to produce tomato plants that stably and reliably produce seedless tomatoes under all environmental, climatic and / or developmental conditions, as well as the seed for such tomato plants, by crossing two plants or progenitor tomato lines which possess the "pk complex" and the "fs complex", as described hereinafter. These two progenitor plants are referred to herein as the "progenitors pk, fs".

General description of the prior art In modern agriculture, tomatoes are more often developed by the grower / producer on hybrid tomato plants developed from hybrid tomato seed. The production of such hybrid seed is usually not carried out by the producer itself, but by highly specialized companies of plant producers who develop and market such hybrid seed, and who through strict quality control can ensure the uniform quality of the seed. seed. As a general rule, hybrid seed is obtained by crossing two different tomato progenitor plants, which most frequently belong to different lines. Using cultivation techniques and plant development techniques known per se, such hybrids can be provided with desired, highly specific properties, which makes it possible to "design" the hybrids, for example, to confer hybrid, heritable, predetermined characteristics to the hybrid plants. . This is usually achieved by properly choosing (the properties of) the two parent lines that are crossed to provide the hybrid seed. These are usually inbred lines, obtained by self-fertilization (self-pollination) over several generations, and such inbred lines will usually have again been specifically "designed" by the cultivator to provide the hybrid progeny with the desired properties, when they cross with another - usually predetermined - inbred progenitor line. As a rule, such progenitor lines will be genetically homozygous and identical (for example as a result of inbreeding) so that they can provide, in a stable and reliable manner, combinations of genetically uniform - albeit heterozygous - hybrid lines, which can ) combine the properties of the parent lines. In doing so, the objective is on the one hand to cross certain properties of the progenitor lines as purely as possible in the seed, while on the other hand the known effect of heterosis or inbreeding development is used, which can provide properties ( improved) regarding -among others- the development of plants and fruits and with this of the yield. This effect of heterosis is obtained when / because the parent lines used are not related with respect to certain genetic properties (for example, when the progenitor lines are genetically "separated"). For a further description of plant development techniques in general, and tomatoes in particular, using classical cultivation techniques, including the formation of hybrids, reference is made to the known manuals, the contents of which are incorporated by reference in the I presented. Also, in this description, unless otherwise indicated, the terms and definitions used herein are those used in genetics (Mendelian), for which reference is made to M.W. Strickberger, Genetics, Second Edition (1976), in particular pages 113-122 and 164-177. As mentioned herein, "gene" generally means an inherited factor that determines "a biological characteristic of an organism (for example a tomato plant), an "allele" is an individual gene in the gene pair present in the tomato plant (diploid). A plant is called "h omoci go ta" for a gene when it contains the same alleles of that gene, and it has been used for a gene when it contains two different alleles of the gene. gene (form of a) dominant and the use of lowercase letters denotes a recessive gene: "X, X" denotes therefore a homozygous dominant genotype for the X gene or property; "X, x" and "x, X" denote heterozygous genotypes; and "x, x" denotes a homozygous recessive genotype. As is commonly known, only the homozygous recessive genotype will generally provide the corresponding recessive phenotype (e.g., it leads to a plant showing the property or trait "x") while heterozygous and homozygous dominant genotypes in general will provide the corresponding dominant phenotype ( for example, they lead a plant to show the property or trait "X"), unless other genes and / or factors such as multiple alleles, suppressors, codominance, etc., (also) play a role in the determination of the phenotype. 'The tomatoes that are currently on the market have the disadvantage that they contain seeds (pips). The presence of these seeds for many consumers is detrimental to the attractiveness of tomatoes. Also, in the preparation of a large number of tomato-based products, in particular tomato-based food products, the seeds have to be removed, for example by sieving, optionally after mashing, boiling or pulping. , which involves additional procedural steps. This is true for the preparation of food products on an industrial scale, such as mashed potatoes, soups, juices or tomato-based sauces, such as for the domestic preparation of dishes or food products. Because of this, in the last 15-20 years, several researchers and tomato growers have tried to develop tomato plants that produce seedless tomatoes. However, despite their efforts, which are discussed in the references mentioned in this application, no commercially acceptable seedless tomato, tomato plants or hybrids that develop such seedless tomatoes, or seed for them, have reached market. The tomato flower consists of an ovary, above which is a pistil. Around the pistil there are several stamens, which produce pollen. In the ovary there are several pre-embryos / embryos that develop (after pollination with pollen) in seeds. The tomato plant can be considered a "forced self-pollinator", which means that almost exclusively only its own pollen ends up on the stamen of the flowers of the same plant, and with this pollinates the pre-embryos. As soon as the pre-embryos pollinated in the ovary are formed, the ovary begins to develop in a tomato (fruit) that contains within it, at the same time, the developing seed. In principle, fruits will only be formed when the pollinated seeds are developing in the ovary; If the embryos or pre-embryos are not pollinated, no fruit will develop.

In the tomato, a gene is known, called the gene pat-2 (also sometimes called pa-th-2), which codes for the property of the parthenocarpy. This gene, when present as a double recessive (pat-2, pat-2) leads to developments of fruit (fruit flesh) without the concomitant development of the seed. In other words, a parthenocarpic plant can develop fruits even without pollination. However, in nature, or in the greenhouse (the phenotype of) the parthenocarpy will usually be only partial; Factors that are responsible for the absence or partial presence of seeds are present in the alleles. In partial parthenocarpy, the seeds are or can be formed in (another) part of the fruit, with the result that the fruit will develop or grow irregularly. The partial parthenocarpy therefore leads to irregular shapes of the fruit, and the resulting deformed fruits are highly unattractive to the consumer. The parthenocarpy gene is extremely rare in nature. This is because, when a fruit is formed based on the total parthenocarpy, no seed is developed within the fruit, so that the genes coding for parthenocarpy are not passed on to the next generation, and the generational line It is finished. For the tomato grower, the total / parthenocarpy phenotype leads to seedless fruits, which makes seed production impossible. The property of parthenocarpy lies in several alleles. The phenotype of the total parthenocarpy can only occur when the "mother" (for example, the tomato plant, the flower of which is pollinated with pollen) as well as the "father" (for example the tomato plant that provides the pollen) ) both are genetically homozygous with respect to parthenocarpic property. This is because, in the fruit "in is Tado na ci t e" usually there are several developing seeds, at least one of which can not become homozygous recessive for parthenocarpy if one parent is a heterozygote. The partial parthenocarpy (in the developing tomato, as a result of at least one seed that is not double recessive with respect to the parthenocarp) may again cause the fruit to develop in a deformed manner.

Another main problem with the parthenocarpy, for example in addition to the low yield of the seed and very unequal fruits in size and shape within the groups or within the plants, due to the partial presence or the non-presence of the seed in the fruits , is a strong dependence on the environment (temperature, light conditions). For the above reasons, neither the plants that are parthenocarpic to a very high degree, nor the plants that (can) give rise to the partial parthenocarp, can be used for the reliable production of seedless tomatoes. In addition to the parthenocarpy, another property that may appear in the tomato is that of functional sterility (indicated here as "FS"). A recessive double floor with respect to FS ( "fs, fs") leads to a tomato plant with a pollen tube is completely closed, so that the full and fertile pollen can not leave the pollen tube or even by vibration or other mechanical influences (bumblebees, insects or a vibrator). The pollen of a tomato plant that has the double recessive phenotype ("fs, fs"), can only be released by physically opening the pollen tube manually (by cutting or with scissors), after which -in practice- the pollen has to be manually removed from the open pollen tube, for example by scraping. For fertilization of the same or another tomato plant, the pollen must then be applied to the pistil of the flower, which in practice must also be carried out manually. In any other "natural" way (for example without the aforementioned human intervention), the pollen from a functional sterile flower is not released and therefore is not available for fertilization of a pre-embryo. A recessive, functionally sterile double plant therefore does not fertilize the pre-embryos, thus terminating the generational line, so that the recessive genes for functional sterility are not passed on to the next generation. In nature, with a double recessive phenotype for functional sterility, no fertilization of the pre-embryos will take place, so that no fruit (tomato) will be formed. It has been suggested that the role of such self-sterility genes in nature may be to prevent self-pollination and thus to maintain the heterozygote quality in plant populations through forced dissociative mating. Functional sterility is considered a form of a more general property of that which occurs in tomato called self-sterility, which can occur in two types, for example, male sterility: self-pollination is not possible due to lack of viable pollen (ms ) or degenerated stamens (yes, without stamen). When male sterility is to be introduced into a hybrid tomato seed, commercial (seed), the producer must plant twice the amount of seed and removed before planting 50% of the plants ms pk heterozygotes, recognizable by a marker gene for ms. This is not completely possible due to crossing over problems. sterile functional; viable pollen is present but can not reach the pistil due to some morphological deviation of the flowers. Functional sterility (fs) itself can also be distinguished into four different types, for example: type ps: a style phenomenon exerted as a result of the strong twisting and shortening of the stamens; This property in general provides the easy self-pollination and the greater receptivity of the style, which makes it not very suitable for the production of hybrid seed. type ps-2: a type of anther bag that does not open, successfully used in the production of hybrid seeds. - ex type: exercised style, on stamens of easy self-pollination and low stigma receptivity makes it less suitable for hybrid seed production. short style type: the stigma is located below the anthers, the main disadvantage is its high level of self-pollination. Parthenocarpy and functional sterility (particularly of type ps-2) in tomatoes, as well as the genetic basis thereof, have been investigated in the prior art. S. Lin, in Dissertation Abstracts International, Vol. 42, No. 9, 1982, page 3514B, describes that the parthenocarpy of the tomato line "Severi anin" is controlled by a simple recessive gene, called pat-2. Lin further describes that the crossing of "Severi anin x Posi ci onal Sterile (" Pa t -Ex ") provides a sterile stigma line of positional parthenocarpy (Pa t -Ex), which can be used as a female line in The production of hybrid seed Fl without emasculation, Lin also describes that the Fl of the cross between "Severi anin" and the line "pa t -Ex" (homozygous pat-2 / pat-2) preserves its stability to produce parthenocarpic fruits. two separate documents from Session II -Male Sterility and Parthenocarpy, of the IXth Meeting of the Eucarpia Tomato Working Group, May 1984, J. Philouze and Ch. Georgiev et al., Respectively, describe parthenocarpic tomato plants that possess the pat-2 gene, as found in and derived from the "Severi ani n" line. In a separate document from the same meeting, Hr. Geordiev and B. Atanassova describe the use of a sterile ps-2 line with the short style in the production of hybrid tomato seed. Ch. Georgiev, in Genetika I. Selektsiya, Vol. 18, No. 3, 1985, pages 264-266 describes that parthenocarpy was discovered in the course of the transfer of sterility ps-2 in orange with CV-Carobeta fruit . This reference establishes that "It was found that the parthenocarpy is hereditary and is controlled by a simple recessive gene, and the evidence of elicitation with the known parthenocarpy genes is in progress". J. Philouze, Agronomie, Vol. 9, No. 1, 1989, pages 63-75 describes a line of tomato called "75/59", derived from a cross between the lines "At om" and "Bubj ekosoko", whose line shows an aptitude for natural but facultative high-level parthenocarpy, at all times of the year. Philouze also describes that the parthenocarpy of "75/59" is recessive, and that the allelism tests show that the parthenocarpy is not due to either the pat-2 gene from "Severi anin" or the pat gene from "Mont". avet 1 91", but it is controlled by at least 3 recessive genes, and more likely by 4 to 6 5 genes, which are independent of pat-2 and are speculated to be independently and cumulatively. However, according to Philouze, the seedless quality can be obtained by using pat-2 alone, as in Severi ani n. Philouze also uses the line "75/59" to produce seedless tomatoes, through a treatment that involves emasculation without pollination. The appearance and weight of the seedless fruits obtained in this way, were comparable to those of the fruits with seed obtained by manual pollination of the flowers of this line. Nuez et al., Zeitschrift für Pflanzenzucchtung, Vol. 96, No. 3, 1986, pages 200-206 describe a study of parthenocarpy in three tomato varieties: "Sub-Artic Plenty", "Severianin", and the line "59/75", developed by Philouze, in the generations Fl and F2 and in the progenies of backcrosses to the parent. The crosses obtained in this way were able to provide seedless fruits after emasculation. By doing this, Nuez et al. "Not surprisingly, there is a lack of information regarding the genetic system for parthenocarpy in some varieties.The expression of the gene for parthenocarpy is strongly conditioned by the environment and the genetic background." Nothing has been well established regarding how such factors interact , what is the mode of gene action under certain determined conditions, or how different genes juxtapose their effects to produce parthenocarpic responses ".

From his study, Nuez et al., Concludes again that the genes responsible for parthenocarpy in "75/59" and "S.A. Plenty" differ from pat-2 in "Severianin"; and the genes from "75/59" and "S.A. Plenty" are called pat-3, pat-4 and pat-5, respectively. However, the above references only describe tomato plants that have either a parthenocarpic phenotype or a self-sterility phenotype. Also, based on the natural variety "Severianin", the previous technique suggests that the presence of the double recessive pat-2 by itself is sufficient to cause parthenocarpy, as is the case in the Severianin line and the seedless line pat-2 , ps-2, described by Georgiev et al., in the Eucarpia Tomato reference. None of the above references describe plants that are recessive homozygotes with respect to the "fs complex" and the "pk complex" as defined herein, nor how such lines may be obtained.

BRIEF DESCRIPTION OF THE INVENTION It has now been found that seedless tomatoes / pips can be produced with advantage using tomato plants - most preferably hybrids - that combine a complex of genes - most likely recessive - that code for the phenotype of parthenocarpy and a gene complex - more likely recessive - which code for the phenotype of functional sterility. These complexes are referred to as the "pk complex" and the "fs complex", respectively, and when combined in a simple tomato plant, line or hybrid are referred to as the pk complex, fs. The two progenitor plants or lines which contain these complexes and which are used to provide the seedless hybrids of the invention, are referred to herein as the "progenitors pk, f s". The invention therefore in a first aspect relates to a method for the production of tomato without seed, a plant that possesses tomatoes without seed or capable of giving seedless tomatoes, or the cultivation of material for such tomato plant such as seeds, which comprises: a. the provision of a first tomato plant containing the complex pk, f s (for example a first parent pk, fs); b. the provision of a second tomato plant containing the pk complex, fs (for example a second parent pk, fs); c. the crossing of the first and second tomato plants for the production of culture material, such as seed, which contains the pk f fs complex; d. the optional cultivation of the culture material obtained in this way, in a tomato plant capable of carrying tomatoes without seed; and. the optional development of the tomato plant until it gives the seedless tomatoes, and the harvest of the seedless tomatoes obtained in this way. More specifically, the invention relates to a method comprising: a. the provision of a first tomato plant containing the pk complex, fs, which is also homozygous dominant with respect to at least one property desired for the production of tomatoes; b. the provision of a second tomato plant containing the pk complex, fs, which is also homozygous recessively with respect to at least one desired property for the production of tomatoes; c. the crossing of the first and second tomato plants for the production of culture material, such as seed, which contains the pk complex, fs and which is also heterozygous with respect to at least one desired property for the production of tomatoes; d. the optional culture of the culture material obtained in this way, in a tomato plant capable of giving tomatoes without seed; and. the optional development of said tomato plant until it gives tomatoes without seed, and the harvest of the seedless tomatoes obtained in this way. In the above methods, step c preferably comprises the following steps: cl. the provision of pollen derived from the first or second tomato plant, respectively, c2. the fertilization of the (the pre-embryos of the) second or first tomato plant respectively, with the pollen obtained in step cl. The culture material obtained in step c) is preferably the hybrid seed or the seedlings obtained from such seed, so that (also) the tomato plant obtained from the culture material in step d) is a plant of hybrid tomato, with the consequent advantages known per se, associated with the known effect of heterosis, increased vigor, etc. Hereinafter, under the term "hybrid", this hybrid cultivation material as well as these hybrid tomato plants are comprised, regardless of whether the latter (already) possess the seedless tomatoes according to the invention. Because of the combination of the recessive phenotype of parthenocarpy and the recessive phenotype of functional sterility, these hybrids do not self-pollinate. However, hybrids will form regularly formed seedless fruits, desired, without the need for (self) -pollution / fertility of the (the pre-embryos on the) hybrid plant (which according to the invention is neither carried out nor required). The first and second tomato plants provided in steps a) and b) respectively, preferably belong to the stable inbred lines, and are accordingly denoted herein as the parent lines pk, fs. These parent lines are preferably genetically stable, as obtained by cultivation / inbreeding over several generations, as described hereinafter.

In the above method, the first tomato plant can serve as the "father" (for example, the plant from which the pollen is obtained) and the second tomato plant can serve as the "mother" (for example, the plant from which the pistil / pre-embryos are fertilized with the father's pollen), or vice versa. This is not essential for the method of the invention, since in both cases a hybrid with the desired pk complex, fs, and therefore with the stable, desired seedless phenotype, will be obtained. In still another aspect, the invention relates to a method for providing a seedless, hybrid tomato plant, or seed or other culture material for such a plant, comprising at least one step of pollinating a first seedless tomato plant. wherein the seedless phenotype is due to the presence of an essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, of which at least two factors provide the first seedless tomato plant with some phenotypic properties of parthenocarpy, and at least two factors provide the first seedless tomato plant with some phenotypic properties of functional sterility; with the pollen obtained from a second seedless tomato plant in which the seedless phenotype is due to the presence of an essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, which at least two factors provide the tomato plant with some phenotypic properties of parthenocarpy and at least two factors provide the tomato plant with some phenotypic properties of functional sterility, and in which said phenotypic properties of parthenocarpy and functional sterility contribute to the phenotype Total seedless tomato plant. The step of pollinating the first seedless tomato plant with the pollen from the second tomato plant involves the opening steps - preferably manually - of the closed pollen tube of the second tomato plant; the withdrawal - preferably manually - of pollen from the pollen tube of the second tomato plant; and the application - preferably manually - of said pollen to the pistil of the first tomato plant. The first and second seedless tomato plants preferably belong to the inbred lines, more preferably to two different inbred lines. This aspect of the invention may optionally comprise the additional steps of allowing the first seedless tomato plant fertilized in this way to form fruits containing the hybrid seed and harvesting said hybrid seed of the fruits; and may also optionally comprise the additional steps of growing a hybrid tomato seed generation, seedless from the hybrid seed, allowing seedless hybrid tomato plants to form fruits (for example seedless tomatoes), and harvesting tomatoes without seed. Still other aspects of the invention relate to the hybrid seed obtained in this way, or optionally to another culture material obtained from said seeds such as seedlings; to seedless hybrid tomato plants obtained in this way; and to the seedless tomatoes obtained as fruits from hybrid tomato plants, without seed. Yet another aspect of the invention relates to processed products, in particular processed food products, obtained from or using the seedless tomatoes obtained in this way. In the above aspects of the invention, two essentially sterile as well as seedless progenitors are prepared - albeit with human intervention - to form the hybrid seed. In a further aspect, the invention relates to a seedless tomato plant, in which the seedless phenotype is due to the presence of an essentially recessive complex of at least 4., preferably at least 5, more preferably at least 6 genetic factors, of which at least two provide the tomato plant with some phenotypic properties of parthenocarpy and at least two provide the tomato plant with some phenotypic properties of functional sterility, and in which said phenotypic properties of parthenocarpy and functional sterility contribute to the phenotype without complete seed of the tomato plant. In a specific aspect of the invention, this seedless tomato plant belongs to an inbred line, and can be used as a parent line to provide the hybrid progeny. In another aspect, this seedless tomato plant is a hybrid obtained from two such seedless, inbred, different progenitor lines, and can be used to develop or obtain seedless tomatoes. In still another aspect, the invention relates to the use of a seedless tomato plant in which the seedless phenotype is due to the presence of an essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, of which at least two provide the tomato plant with some phenotypic properties of parthenocarpy and at least two that provide the tomato plant with some phenotypic properties of functional sterility, in which the phenotypic properties of the parthenocarpy and the functional sterility contribute to the complete seedless phenotype of the tomato plant; as a progenitor plant for obtaining hybrid progeny without seed. This aspect of the invention can be carried out either by pollination of the seedless tomato plant with the pollen obtained from another seedless tomato plant in which the seedless phenotype is due to the presence of an essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, of which at least two provide the tomato plant with some phenotypic properties of parthenocarpy, and at least two provide the tomato plant with some phenotypic properties of functional sterility, and in which said phenotypic properties of parthenocarpy and of functional sterility contribute to the phenotype without complete seed of the tomato plant; and / or by using pollen from the seedless tomato plant, to pollinate another seedless tomato plant in which the seedless phenotype is due to the presence of an essentially recessive complex of at least 4, preferably from less 5, more preferably at least 6 genetic factors, of which at least two provide the tomato plant with some phenotypic properties of parthenocarpy and at least two provide the tomato plant with some phenotypic properties of functional sterility, and in which the Phenotypic properties of parthenocarpy and functional sterility contribute to the complete seedless phenotype of the tomato plant. In this aspect of the invention, two essentially sterile progenitors are prepared as well as seedless - albeit with human intervention - to form the hybrid seed. The pollination step of the first seedless tomato plant with the pollen from the second tomato plant involves the opening steps - preferably manually - of the closed pollen tube of the second tomato plant; the removal - preferably manually - of the pollen from the pollen tube of the second tomato plant and the application - preferably manually - of said pollen to the pistil of the first tomato plant. Yet another aspect of the invention relates to a method for maintaining the seedless tomato plant, in particular to maintain an inbred line of seedless tomato plants, and / or to obtain the seed or other crop material for any plant or plant. line, comprising at least one step of pollinating a seedless tomato plant in which the seedless phenotype is due to the presence of an essentially recessive complex, of at least 4, preferably at least 5, more preferably at least 6 factors genetic, of which at least two factors provide the first seedless tomato plant with some phenotypic properties of parthenocarpy and at least two factors provide the first seedless tomato plant with some phenotypic properties of functional sterility; with pollen obtained from the same plant, or with pollen from another plant that belongs to the same inbred line. The step of pollinating the seedless tomato plant with its pollen involves the steps of opening - preferably manually - its closed pollen tube; remove - preferably manually - the pollen from the pollen tube; and applying - preferably manually - said pollen to the pistil of the tomato plant. This aspect of the invention may optionally comprise the additional steps of allowing the seedless tomato plant fertilized in this way to form fruits containing the seed and to harvest the seed from the fruits; and may also optionally comprise the additional steps of growing an additional generation of seedless tomato plants from said seed. Additional aspects of the invention will become clear from the following description. According to one embodiment of the invention, the essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, comprises at least the genes pat-2 and ps-2, as well as at least 2, preferably at least 3, more preferably at minus 4 additional genes, more preferably such that the pat-2 gene and at least one, preferably at least two, additional genetic factors provide the tomato plant with some phenotypic properties of parthenocarpy, and so that the ps-2 gene and at least one, preferably at least two additional genetic factors provide the tomato plant with some phenotypic properties of functional sterility, in which said phenotypic properties of parthenocarpy and functional sterility contribute to the complete seedless phenotype of the tomato plant.

Brief description of the Figure and definitions The invention will be illustrated by reference to the attached Figure 1, which shows the crossing between the parent lines pk, fs, and also schematically illustrates a general method for developing the progenitor line (s) pk, fs, for example by means of an example preferred of this method that involves the generation of a F6 generation starting from a line of tomato without seed, known, for example the line pat-2, ps-2 of Georgiev. The tomato plants shown in Figure 1 are as follows: 1) Progenitor without original seed: The tomato plant used as the first progenitor (line) to obtain the progenitors fs f pk of the invention. The original seedless parent can be used as the male or female. The original seedless parent will have a seedless phenotype, for example a combination of a parthenocarpic phenotype and a functionally sterile phenotype. Preferably, the partenocarpic phenotype of the original seedless parent is due to the presence of the homozygous recessive pa t-2 gene (pa t-2, pa t-2), but may also be due to the presence of the pa t gene, the genes pa t-3 / pat-4, the pat-5 gene or another gene. Preferably, the functionally sterile phenotype of the original seedless parent is due to the presence of the homozygous recessive ps-2 gene (ps-2, ps-2). However, the invention is not limited thereto, and other seedless lines known per se may also be used. The original seedless parent can be obtained in a manner known per se, for example starting from a known tomato line containing one of the known parthenocarpy genes and / or having a parthenocarpic phenotype, such as Severi ani does not Pat-2 lines, described by Georgiev, Michailov and Popova in the references of Eucarpia Tomato Working Group, or by Philouze in the Agronomie reference, or the parthenocarpic lines containing the pat, pat-3, pat-4 or pathogen genes 5, such as those described in the art; and from a known tomato line with a functionally sterile phenotype, such as the lines containing ps-2 described by Georgiev and Atanassova in the Eucarpia Tomato Working Group reference. These are then crossed and selected to provide the original seedless parent, usually in a generation F2, F3 or later, and / or until a stable seedless line is obtained, suitable for use as an original seedless parent. Alternatively, and preferably, a seedless line known per se is used as the original seedless parent, such as the line ps-2, pat-2 described by Georgiev et al., In the Eucarpia Tomato reference. Again, such a line can also be obtained again from a source of a pat-2 gene and a ps-2 gene, for example analogous to the methods described in the prior art. 2) Original progenitor with seed The tomato plant used as the second progenitor (line) to obtain the progenitors pk, fs of the invention, by crossing with the parent with seed, original. The original seedless parent can be used as the male or female. The parent with original seed has a phenotype with seed, and preferably neither a parthenocarpic or functionally sterile phenotype (although the use of a tomato plant or line with either a parthenocarpic or functionally sterile phenotype is not excluded, and - for purposes of description of the line with original seed - are included within the term "with seed" and "parent with original seed").

As such, any tomato plant, line or hybrid, known per se may be used, including but not limited to all lines or hybrids that are commercially available, such as those mentioned for example in list B of NAKG, The Netherlands, as well as like all proprietary lines for plant producers. Preferably, a tomato plant that belongs to an inbred line or a hybrid tomato is used. The tomato types that were found to be particularly suitable for use as a progenitor with seed in the invention, were lines belonging to cherry tomatoes, tomato lines determinants, and / or tomato lines that possess the genes for resistance to cold such as Luci ao Ha vana. Some other non-limiting examples of suitable lines, commercially available, include Dani el l e and M. H. On e, although commercial producers can, and will usually be able to, use their own owner lines. Other suitable lines may be determined by the person skilled in the art based on the teaching given hereinafter. 3) Progenitor pk, fs The tomato plant containing the pk complex, fs as defined herein, and which can be used to provide a seedless hybrid by crossing with another progenitor pk, fs. Usually, the progenitor pk, fs will be in the form of a line, more particularly an inbred line. The progenitors pk, fs can be obtained by means of human intervention as described below - from the parent without original seed and the parent with original seed (optionally through additional backcrossing), or starting from a parent pkrfs, already established. It is considered that the present invention will usually be marketed either through the commercialization of the progenitor line pk, fs, or through the commercialization of the hybrid seed obtained from two parents pk, fs. 4) Hybrid without seed The hybrid tomato plant, obtained from two different progenitors pk, fs through human intervention as described below.

The seedless hybrid is the plant that will be used by the grower / producer to develop and produce seedless tomatoes. The seedless hybrid will have inherited the pk complex, fs from its two progenitors pk r fs, and therefore will display the seedless phenotype, for example fruits from their flowers without previous pollination.

Method for obtaining progenitor lines pk r fs A method for obtaining progenitors pk, fs is shown in Figure 1 and generally comprises the following steps, discussed further below: a. The crossing of an "original seedless parent" as defined herein with a "parent with original seed" as defined herein to provide a seed Fl generation; b. The self-pollination of the generation Fl obtained in this way to provide an additional generation, hereinafter referred to as the generation F2. cl. The selection of any F2 plants or plants obtained in this way, with a seedless phenotype and causing these seedless plants to self-pollinate, to provide a first generation F3; as well as c2. The selection of any F2 plants obtained in this way, with a functionally sterile phenotype, and causing these plants to self-pollinate in order to provide a second generation F3; d. The selection of any plants of the first or second generation F3 with a seedless phenotype; and. Cause that the plants of the first or second generation F3 with a seedless phenotype self-pollinate in order to provide a generation F4 f. Provoking that the F4 generation plants obtained in this way, which have a seedless phenotype, self-pollinate in order to provide a F5 generation; and optionally causing the F5 generation plants obtained in this manner, which have a seedless phenotype, to self-pollinate in order to provide a F6 generation.

Usually, by the generation F5, and in particular by the generation F6 obtained in step e), the pk f fs complex in the plants obtained in this way, will have stabilized sufficiently, for example it has become "fixed" for the plant of tomato to be used as a progenitor pk r fs in the invention, or to be used as an initial plant or line to obtain other (lines of) progenitors pk r fs, for example by crossing in additional properties or by means of of backcrosses. Since the F3, F4, F5, F6 and additional generations have a seedless phenotype - or in the case of the "second generation F3" at least one functionally sterile phenotype - obtaining the F4, F5, F6 and additional generations, as well as maintaining the progenitor lines pk, fs for the production of the seedless hybrids, will require human intervention as defined hereinafter. This requirement for human intervention to provide additional generation is also generally referred to herein as "provoking self-policing." It has been found that F2 will usually contain only the most approximately 1 or 2 seedless plants in 100 F2 plants, but neither can it provide seedless plants, depending on the parent without original seed and in particular of the parent with seed, original, used. Even when seedless F2 plants are obtained, it was found that the amount of them (for example 1-5%) is significantly lower than 8.25% (for example 1 plant of 16) that was to be expected according to the principles Mendelians if the presence of the recessive double genes pat-2 and ps-2 by themselves were sufficient to provide a seedless phenotype. This shows that the crossing with the parent with original seed apparently introduces some -probably dominant- genes, alleles or other genetic factors that negatively influence the appearance of the seedless phenotype in F2. The F2 will usually contain some functionally sterile plants, for example usually about 10-15 plants out of 100, again depending on the parent without original seed and in particular of the original seedling progenitor. This again is less than 25% that would be expected according to Mendelian principles, if the presence of the double recessive ps-2 by itself were sufficient to provide a functionally sterile phenotype. This shows that also the presence of the desired functionally sterile phenotype is determined by a complex of genetic factors. The seedless plants from F2 are selected and caused to self-pollinate, to provide an F3, referred to herein as the "first generation F3". It was found that, in spite of the seedless phenotype of the F2 plant, sometimes not all the F3 plants obtained in this way will show the seedless phenotype of the F2 plant, but they can form 0-100%, and more frequently will form only about 10-20% of the F3 plants. This again confirms that the seedless phenotype in these F2 plants is caused by a gene complex (for example the pk complex, fs of the invention), and not by the homozygous recessive genes pat-2 and ps-2 alone, as in the progenitor without original seed. This also shows that in generation F2, the complex pk, f s is not sufficiently fixed-for example genetically not sufficiently homogeneous-to provide completely seedless progeny. Because of this, the seedless F2 plants obtained as described above are also unsuitable for use as progenitors pk r fs in the invention. Plants of the first generation F3 that show the seedless phenotype are selected, and are caused to self-pollinate to provide an F4. Again, it is usually found that not all F4 plants obtained from the seedless F3 plants will display the seedless phenotype: the number of seedless F4 plants may vary from 0 to 100%, and is usually about 10-20% of all F4 plants. Also, not all F4 plants are found as seedless under all environmental conditions. This again shows that the complex pk, f s has not yet been sufficiently fixed in these plants F3 or F4 for them, to be used as progenitors in the invention. The seedless plants of generation F4 are then again self-pollinated to provide an F5 generation, and the seedless plants of generation F5 are self-pollinated to produce an F6. Again, in F5 and sometimes also in F6, some seed plants are obtained because the pk, fs complex was not yet sufficiently fixed in seedless F4 or F5 generations, respectively. Usually, by generation F6, the pk r fs complex in seedless F6 plants will be sufficiently stable, so that all F6 seedless plants exclusively provide seedless F7 plants when they are self-pollinated. This is also an indication that the inbred F6 generations obtained in this way can be used as progenitors pk r fs in the invention. If generation F7 still provides some plants with seed, generation F7 can again be self-pollinated to provide an F8, etc., until a generation is obtained in which the complex pk, f s is sufficiently fixed. However, this is not usually required and is also not preferred. Also, if by generation F9 and in particular by the FIO generation, the pk f fs complex has not yet been sufficiently set, it will usually be assumed that this inbred line can not be used as a parent line pk, fs in the invention . In general, only a small amount of seedless F2 plants will "do it" to F6, depending on the original seedless parent, but in particular the parent with the original seed used. Also, in the generation of F6, some selection pressure can be applied in order to test the stability and reliability of the seedless phenotype under all environmental conditions. For example, factors such as light, temperature can be used to "test" and / or fix the stability of the seedless phenotype of generations F3, F4, F5 or F6. In addition to the seedless F2 plants, also the F2 plants which only show a phenotype of functional sterility are self-pollinated, to provide an F3 generation, referred to herein as the "second generation F3". This second generation F3 will usually comprise essentially all functionally sterile plants, and may comprise some seedless plants, for example about 1-3 of 40 F3 plants (which can be easily recognized and selected because they are the only ones in the second F3 that will develop fruits). If so, these seedless F3 plants are self-pollinated to provide an F4 generation, followed by an F5 and F6, and optionally an F7 and F8, etc., essentially as described for the first generation F3. Again, not all the seedless plants of the second generation F3 will now do the F6, again depending on the parent without original seed, and in particular the parent with original seed used. In the previous methodology, for a given combination of parent without original and progenitor seed with original seed, it is possible that no seedless plants are obtained in F2, and only few functionally sterile plants. These functionally sterile F2 plants are then self-pollinated. However, if in the F3 generation obtained in this way, no seedless plants are found again, it will usually be assumed that this particular combination of parent without original seed and parent with original seed, can not be used to provide a progenitor pk f fs according to the invention. A possible explanation for this may be that the original, used parent did not contain all the genetic factors (eg genes, alleles or other factors) necessary to "complete" the pk complex, fs, in relation to the genes already present in the parent without seed, original, used. However, the invention is not limited to any specific explanation or hypothesis regarding which gene or genes, alleles or other genetic factors constitute the pk complex, fs according to the invention, nor to which or how many genes or genetic factors (such as suppressors, modulators, etc.) are necessary or not for the expression of the desired parthenocarpic phenotype and / or the functionally sterile phenotype of the invention. However, as the present disclosure teaches to the person skilled in the art how progenitors pk, fs can be obtained starting from plants or tomato lines described in the art, such knowledge about the precise genetic constitution of the pk r fs complex used in the invention, it is also not considered to be required for the person skilled in the art to practice the invention (such lack of detailed knowledge of the precise genetic basis of a given phenotype is not unusual in the art). This is because the expert can easily determine, for example based on the simple procedure described above, which seedless tomato plants or lines can be case, such different complexes will usually have some, and probably most, s, alleles or other tic factors in common, more important) . In spite of the above, it is assumed that the "pk r fs" complex comprises at least the or allele of the parthenocarpy of the original seedless protor, combined with at least one additional tic factor (e.g., the , the allele or another factor that can influence the expression of the parthenocarpy); and / or comprises at least the functional sterility gene of the original seedless parent, also combined with at least one additional genetic factor (eg, gene, allele or other factor that can influence the expression of functional sterility), or a combination of them. The applicants' research has also shown that the pk, fs complex probably consists of recessive genes, alleles or genetic factors, since the phenotype of the lack of seed is only uniformly inherited by hybrids obtained with another progenitor pk, fs. Because of this, for the purpose of this invention, the complete pk, fs complex will be considered "essentially recessive"; and a crossing with another progenitor pk, fs will usually be necessary to ensure that all genes, alleles or factors that make up the complex are uniformly inherited and expressed by the hybrid generated in this way. However, from the intensive research of the applicants that has now been extended for more than 10 years, since still no satisfactory model has suggested by itself that it can clarify the number and / or character of the genes, alleles or other genetic factors, which are necessary to constitute a pk complex, fs of the invention, or which can even explain the very low appearance or sometimes even the complete absence of seedless (or even functionally sterile) phenotypes in the generations Fl, F2 , F3 and even F4, obtained from the original progenitors without seed and with seed. This shows that the factors that determine the true seedless phenotype of the invention are much more intricate than those which are suggested in the prior art (for example not determined by a combination of (1 + 1), (2 + 1) or even (3 + 1) separate genes), and also explains why the prior art was not able to provide plants or tomato lines that can be used to produce seedless hybrids in a stable and reliable manner, and under all environmental conditions. It is possible that the pk, fs complex of the invention comprises one or more genes, alleles or other genetic factors (or a combination thereof) either for parthenocarpy and / or for functional sterility that have not yet been described per se. in the technique. Similarly, it may also be possible that the pk, fs complex of the invention comprises one or more known parthenocarpy genes such as pat-2, pat-3, pat-4 or pat-5 (or a combination thereof), possibly in combination with one or more genes, alleles or other unknown genetic factors that influence the expression of parthenocarpy; as well as one or more of the known functional sterility genes, such as ps, ex or short s tyl e, again possibly in combination with one or more genes, alleles or other unknown genetic factors that influence the expression of the functional sterility. It is even possible that the genes, alleles or genetic factors involved in the properties of parthenocarpy and functional sterility do in fact influence one over the other for expression (for example in a way not yet evaluated) so that the presence of one or more genes, alleles or genetic factors that determine the parthenocarpy are (also) required for the good expression of the functional sterility of the progenitor lines pk f fs and the hybrids obtained from them, or vice versa, to jointly provide the phenotype without seed, desired. In this specific explanation of the seedless phenotype of the invention (also) it can not be completely excluded that the pk f fs complex of the invention comprises a simple recessive gene for parthenocarpy (such as pat-2), in combination with a complex of genes for functional sterility; or a simple recessive gene for functional sterility (such as ps-2) in combination with a gene complex for parthenocarpy. For the scope of the present application, the lines pa t-2, ps-2 described by Georgiev are not included within the term "complex pk, fs" or "progenitor pk r fs", and also not within the scope of the invention. For purposes of further describing the pk complex, fs of the invention - and in particular to distinguish the plant pk, fs from the seedless lines known in the art - the pk complex, fs can be considered as having a "pk part" (for example those genes, alleles or other inheritable factors that can influence the formation of parthenocarpic properties in the seedless phenotype) and a "fs part" (for example those genes, alleles or other inheritable factors that can influence the formation of the functionally sterile properties in the seedless phenotype). However, this way of considering the complex pk, fs (for example, as separate pi and fs parts) may not describe the actual situation in plants, because - as explained above - it can not be excluded that some genetic factors from the part "pk" can also influence or be necessary for the "part fs" or vice versa; and factors may also appear that influence or even be required for the "part pk" and the "part fs", and consequently may be considered as belonging to both. When the pk complex, fs is defined in this manner, the "pk portion" of the pk f fs complex according to the invention comprises at least two, and preferably at least three, genetic factors; and the "fs part" of the pk r fs complex also comprises at least two, and preferably at least three genetic factors (in which the factors that influence the parthenocarpic properties as well as the functional sterility of the plant, are counted as belonging to the "part pk" as well as the "part fs." Similarly, a factor from the"part pk" that influences the "part fs" or vice versa, is also counted as belonging to both). In this definition, "genetic factors" can be genes, alleles, multiple alleles or a combination thereof, as well as other factors that can influence expression, such as suppressors or promoter, co-dominance, incomplete dominance, etc. When this way of describing the pk complex, fs of the invention is applied analogously to the seedless lines known per se in the art, such as the line pa t-2, ps-2 of Georgiev, it will be clear that in these known plants , the "part pk" consists of a simple factor (for example gene), and the "part fs" consists of a simple factor (for example gene), which are also completely independent in their interactions as well as in their inheritance capacity. Such plants or lines are not within the scope of the terms "complex pk, fs" or "progenitor pk r fs" as used herein. Similarly, by this definition, the plants or lines in which the "part pk" consists solely of a simple genetic factor, and the "part fs" consists solely of two genetic factors, or in which the "part pk" consists of only two factors, and the "part fs" consists of a simple genetic factor, are not generally within the scope of the terms "complex pk, fs" or "progenitor pk, fs" as used herein, since these combinations are apparently sufficient to explain the inheritance capacity of the pk complex, fs and / or the seedless phenotype found in the invention. By this definition, the technique has not mentioned or suggested at all that the presence of a complex pk f fs in which the "part pk" consists of at least two, preferably of at least three genetic factors, and also the "part fs" "comprises at least two, preferably at least three genetic factors, is necessary to provide, in a stable and reliable manner, seedless hybrids that will form seedless tomatoes under all environmental, cultivation or development conditions.

Also, none of the technique describes tomato plants or lines that contain a pk complex, fs, according to this definition. Alternatively, the pk, fs complex could also be described as an essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, of which at least two factors provide the first seedless tomato plant , with some phenotypic properties of parthenocarpy and at least two factors provide the first seedless tomato plant with some phenotypic properties of functional sterility, and in which the phenotypic properties of parthenocarpy and functional sterility contribute to the phenotype without complete seed of the plant. Again, tomato plants with a pk f fs complex according to this definition have not yet been described or provided by the art. In a preferred embodiment, the original seedless parent is a plant or line pa t-2, ps-2 such as the pat-2 line, ps-2 described by Georgiev. In this modality, it is assumed that -by the above definition- the "pk part" of the progenitor pk r fs derived from the seedless parent pat-2, original ps-2 comprises the pat-2 gene, combined with at least one additional genetic factor (for example, a gene, allele or other factor that includes the expression of parthenocarpy); and that the "fs part" comprises at least the ps-2 gene, combined with at least one additional genetic factor (e.g., gene, allele or other factor that influences the expression of functional sterility), or a combination of the same. Alternatively, this pk complex mode, fs, can also be described as an essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, comprising at least the genes pat-2 and ps-2, as well as at least 2, preferably at least 3, more preferably at least 4 additional genes, more preferably such that the pat-2 gene and at least one, preferably at least two, additional genetic factors provide the tomato plant with some phenotypic properties of parthenocarpy, and so that the ps-2 gene and at least one, preferably at least two additional genetic factors provide the tomato plant with some phenotypic properties of functional sterility, and in which the phenotypic properties of the parthenocarpy and Functional sterility contributes to the seedless, complete phenotype of the tomato plant. Previously, the method for obtaining the progenitor lines, pk, fs of the invention is specifically described starting from a line without known seed, such as a line pat-2, ps-2. However, based on the present teaching, it will be clear to the skilled person that there will be possible equivalent methods to obtain the progenitor lines pk f fs of the invention (e.g. lines with a pk, fs, "complete" complex), starting at starting from known lines that carry genes for parthenocarpy and / or functional sterility, to which the additional genes necessary to "build" the complete pk complex, fs, are then "aggregated" from other tomato lines known per se . Such equivalent methods will generally be encompassed within the scope of the invention. In addition to providing the seedless hybrid with the pk complex, fs, the progenitor lines pk, fs are preferably such that they confer on their seedless hybrid progeny a number of predetermined properties that are desired for reproduction, cultivation and / or development of tomato plants, and / or for tomatoes produced by such plants. These properties are not specifically limited and for example include early development, increased growth, increased production, any form of the plant or fruit (including round, cylindrical, pear or cherry), the size or quality of the fruit, increased resistance against viruses or other diseases, increased resistance to cold, long shelf life, etc., as will be clear to the person skilled in the art. For this purpose, the progenitor lines pk, fs of the invention can be "designed" with the desired properties, for example by the appropriate choice of (the properties of) the lack of original seed and in particular the progenitors with seed (provided when the progenitor with original seed provides the additional genes necessary to "complete" the pk r fs complex). Alternatively, and usually, the progenitor lines pk, fs with the desired properties are obtained starting from a progenitor plant or line pk r fs already available / established (such as those obtained as a previous F6 generation), by introducing the desired property or properties within the parent pk f fs from a line of tomato known per se, for example in a manner analogous to the breeding techniques known per se. By doing this, a tomato line known per se that possesses the desired property (which will usually be a tomato with seed, but can also be a parthenocarpic, functionally sterile, or even another line without seed) is crossed or made to be crossing with a parent line pk r fs to provide a Fl generation (which usually will not be seedless), which is then self-pollinated to provide an F2 generation, from which seedless and self-pollinated plants can then be selected to a generation F3, F4, F5, etc., until a stable inbred line possessing the desired properties is obtained, as well as the pk f fs complex. In principle, this method can be essentially the same as the method described above, although now a progenitor pk, fs used as an initial material instead of a "progenitor without original seed". In this way, starting from a progenitor pk rfs obtained as described above, a complete range of progenitor lines pk r fs with desired properties can be obtained, which can then be crossed with each other - for example by means of human intervention-to provide the desired seedless hybrids. The use of a progenitor pk f fs as an initial material in this method will generally have the advantage that it will ensure at the outset that all the genes required to constitute the complex pk, fs are present in the initial material. (In addition, although not preferred, the seedless hybrids of the invention can also be used as a source of the pk r fs complex for the establishment of new progenitor lines pk r fs, again essentially as described above). In this embodiment, the above method for obtaining the progenitors fs rpk of the invention can therefore comprise the additional steps of g. cause the generation F6 (progenitor pk r fs) obtained in this way to cross with a tomato plant that carries at least one desired property to generate a generation Fl '; and h. repeat steps b) to f) on the generation Fl 'obtained in this way, to generate an F6.

Another alternative is to carry out - for example as a part of the method described above - a backcross of the seedless plants of the (first or second) generation F3, F4 or F5 obtained from the original parent without seed and with seed, with one (another) tomato plant or line that carries the desired property. The generation obtained in this way is then used and treated in the same way as the generation Fl obtained from the crossing between the parent without original seed and the parent with original seed, for example via steps b) -f) as shown in FIG. described above, to provide another progenitor line pk, fs. Optionally, such a backcross F3, F4 or F5 can be repeated more than once (for example, on an F3, F4 or F5 obtained from a backcrossed Fl), in order to introduce several desired properties from the plants of different tomatoes known per se in the final parent line. In this way, any desired properties can be introduced into the parent lines during and as part of the progeny development program pk f fs, in fewer generations than would be required to introduce them in a parent line pk, fs established. In this modality, the above method for obtaining progenitors pk r fs can therefore understand the additional steps of: i. cause the plants of the first F3, second F3, F4 or F5 obtained after step cl), c2) e) of) respectively, to cross with a tomato plant that carries at least one desired property to generate a generation Fl " and j repeat steps b) to f) on the Fl "obtained in this way, to generate an F6. In order to provide hybrids, and / or in order to promote heterosis and vigorous development, the progenitor plants or lines pk, fs are most preferably homozygous with respect to one or more of the desired additional properties, in which a progenitor plant will be homozygous dominant, and the other plant will be homozygous recessive, so that the resulting hybrid will be heterozygous with respect to said property, as is generally known per se for obtaining hybrid tomato plants by breeding.

The number, as well as the nature of the properties for which one progenitor will be homozygous recessively and the other will be homozygous dominant, will preferably be chosen such that the desired effect of heterosis is obtained in the resulting hybrid. For this purpose, for each of the various properties, homozygous dominant and homozygous recessive genotypes can be distributed over the progenitor plants in any desired combination, which means that a progenitor plant can be homozygous dominant with respect to a desired property, and homozygous recessive with respect to another property, and in which case the other progenitor plant will be homozygous recessive and homozygous dominant respectively, with respect to these properties. All this will be clear to the person skilled in the art of plant reproduction. It will also be clear to the skilled person that in the production of seedless hybrids of the invention, hybrid uniformity (seed) will be essential for the seed producer as well as for the tomato producer, since this will not only ensure uniform quality of the cultivation material, but also of the hybrid plants and the tomatoes eventually produced. This is especially important for the development of tomatoes on a large scale, as well as for the end user, for example for industrial producers - of tomato products as well as for consumers. As is generally known in the art of plant breeding, the preferred way to ensure, in a repeatable and reliable manner, the uniformity of a hybrid is to use "pure" progenitor lines, obtained by inbreeding over various generations. The use of such inbred lines is in general also required for obtaining heterosis, for which progenitor lines in general must be genetically "separated". Usually, the previous methods for obtaining progenitors pk, fs as an inbred F6 (for example starting either from an original seedless parent, from another parental line pk f fs, or obtained through a backcross F3, F4 or F5 as described above) will at the same time ensure that the resulting progenitor lines pk, fs are also sufficiently pure for any other desired properties.

The presence of the pk complex, fs in the progenitor lines pk, fs also means that these lines are not capable of reproducing by themselves (for example of self-pollination). This means that the human intervention-carried out essentially as described below for obtaining the seedless hybrids-required to obtain progenitor lines pk f fs (for example by the methods described above), but also the maintenance of the progenitor lines pk, fs within the breeding station. Also, since the progenitor lines pk, f s themselves have the seedless phenotype, these, without any such intervention, will also produce tomato without seed. In this way, the progenitor lines pk, fs, the previous methods for obtaining and / or maintaining these, the seed or other material of culture for these parent lines, as well as the use of these parent lines in the provision of the Hybrid seedless progeny (for seed), form additional aspects of the invention, such as seedless tomatoes produced by these progenitors pk r fs.

Method to provide seedless hybrids In order to provide the hybrids of the invention, two progenitor lines pk r fs must be crossed. However, since the progenitor lines pk r fs are sterile, and therefore can not pollinate themselves or any other plant, this requires human intervention. (In essence, the invention comprises the provision and maintenance of two different inbred, sterile progenitor lines, and which derive seeds as well as hybrid progeny from these two sterile as well as seedless lines.This can not occur in nature. reason also, progenitor lines pk, fs as well as seedless hybrids in general can not be considered a variety within the meaning of the UPOV treaty). This human intervention generally comprises the fertilization of the pre-embryos of the flower of the first or second progenitor pk, fs, respectively, with the pollen obtained from the second or first progenitor pk f fs, respectively, dependent on the father's choice and the mother. Because the pollen tube of the parent plant is closed, as a result of the functionally sterile phenotype, the pollen must be provided by opening the pollen tube, with machine or preferably by hand, in practice by cutting, or cutting with pollen tube scissors. After this, the pollen is removed from the pollen tube, again preferably by hand, for example by scraping, after which the pollen obtained in this way is applied to the flower / pistil of the mother plant, again preferably to hand, such as by brush or other suitable manner, such as spray, to fertilize the (pre-embryos) of the mother plant. Theoretically, it is also possible - after opening the pollen tube, so that the enclosed pollen is released / accessible for dispersion / distribution - to use other methods to transfer the pollen to the pistil of the mother plant, such as by the use of insects, especially when the pollen tube of the mother plants has not been opened or the stamen of the mother plant has been removed to prevent fertilization of the mother plant with its own pollen. Manual fertilization, as described hereinabove, is nevertheless highly preferred, for reasons of efficiency, as well as to avoid fertilization / contamination of the mother. In addition, manual pollination is a technique commonly used to obtain hybrid tomatoes, for which purpose for purposes of the invention only the opening and scraping of the pollen tubes has to be added. After pollination, the mother plant "fertilized" in this way can also be grown until it gives tomatoes, which will contain the hybrid seed of the invention. This hybrid seed can then be harvested in a manner known per se, optionally be further processed, as well as packaged for storage, transport or sale. Said hybrid seed, optionally in packaged form, forms an important aspect of the invention from a commercial point of view, as will be clear to the skilled person. To obtain the seedless hybrid tomato plant and the seedless tomatoes, the hybrid seeds can be sown in a manner known per se, or be germinated in a manner known per se in the art, and then cultivated to obtain tomato plants, which (can) carry the seedless tomatoes of the invention. As mentioned earlier in the present, the (self) -pollination / fertilization of the hybrid does not occur; however, a regularly formed fruit is produced on the unfertilized hybrid. With the improved seedless hybrids of the invention, it is found that almost all (for example more than 80%, and sometimes 95-99% or more) of the flowers on the seedless hybrid will develop fruits (for example lead to "group"). of fruits ") as well as they will develop good fruits, and they will do it reliably under all environmental or development conditions. This makes the seedless hybrids of the invention a marked improvement over the seedless lines described in the art, which gave many poorer results, especially under bad light conditions and / or low temperature. The seedless tomatoes obtained in this way can then be harvested and marketed and / or consumed as such, optionally after one or more additional processing steps, such as sorting, washing or packaging. The invention therefore in further aspects relates to the culture material for tomatoes such as seeds or seedlings (optionally in a container), as well as the seedless tomatoes obtained and / or obtainable as described hereinabove, and / or suitable for use in the method (s) described herein. The seedless tomatoes according to the invention can also be further processed in a manner known per se to tomato products, in particular food products, which may or may not be in a ready form or suitable for the end use. In this regard, the tomatoes according to the invention have the advantage that they can be processed directly, without an additional step to eliminate the seed / nuggets in the production process. The invention in a further aspect therefore relates to the products, in particular to the food products, obtained from seedless tomatoes according to the invention, as well as to a method for obtaining said food products, in which the tomatoes are processed to these products without a separate step to eliminate the seeds. Such a method may therefore, inter alia, comprise mashing or crushing to form pasta, otherwise, tomatoes, optionally followed by incorporation or addition of additional desired ingredients, and packaging of the tomato product. obtained in this way, without seeds or residues thereof, in suitable containers for storage, transport or sale, in which said method does not comprise a step to remove any seeds / seeds between the reduction to pulp of the tomatoes and the packaging of the product. For such end use, yet another advantage of the seedless tomatoes of the invention is that they will have a higher content of fruit flesh (expressed as dry weight) compared to tomatoes with seed harvested at a corresponding time, for example 1 % more, based on the total weight of the tomato (for example on average approximately 5.5 to 6.5 grams of dry material for seedless tomatoes compared to approximately 4.5 to 5.5 gram of dry material for tomatoes with seed, on a total weight in the harvest of approximately 110-120 grams). In terms of the performance of the dried material, this means an increase of at least about 20% (in which in addition to the dried material of the tomatoes with seed they will also include the nuggets).

EXPERIMENTAL PART Introduction Experiments were carried out using lines from a collection of homozygous inbred lines used to obtain commercial hybrids. In a first series, a determinant line, of small fruit, with the genes ps2 and path2 (received from Dr. Hristo Atanasov Georgiev) was used as the initial material. This lines (indicated here by the number 90173), proved to be seedless under conditions of development in the Canary Islands . From this seedless line, additional seedless lines are obtained by crossing with the lines in list B of NAKG, Holland; with unlisted hybrids or with open pollinated varieties from different countries (usually fresh tomato varieties for the market and industry with properties such as long shelf life, high external fruit quality, resistance to diseases and so on).

From these crosses, the Fl generations were developed, which were self-pollinated to provide an F2 that was selected for the properties fs, pk and / or fs. In F3 the fspk plants were backcrossed with old or newly developed breeding lines. In a second series, an advanced reproductive line with a functionally sterile phenotype (fs) and a parthenocarpic reproduction line based on the Severianin pat-2 gene were used as initial material. (As such, these pat-2 lines generally have the problem of not having fruits of uniform size and shape, and low absence of seeds in highly parthenocarpic lines). These plants fs and pk were crossed, and from these crosses were developed the generations Fl, which were self-pollinated to provide a generation F2 that was selected for the properties fs, pk and / or fs. In the F3 generation the fspk plants were backcrossed with old or newly developed breeding lines.

Initial experiments and comparative results From the work with an FS line, it was found that ps2 itself is not sufficient for good and sterile stable plants in F2, F3 and in higher F lines. Apparently some modifying or additional genes are necessary for the complete expression of this complete sterility. In some cases, small fruits without seeds were found in the fs plants. The development of the next generation gave the same result. This indicates that the development of the parthenocarpic fruit is present, although not completely, and probably due to different genes from path2. Also, normal fs plants do not develop fruits and flowers fall if they are not manually pollinated. Working with path2, it was especially noted in F3 that there were different levels of fruit parthenocarpic development. As a measurement, the number of fruits grown on the third castrated cluster of a group of 20 plants was used. This indicates that more genes are required with the parthenocarpic expression.

Working with fs, pk and lines of pure reproduction it was noted that in some F2 there was no fspk and in others for fewer numbers than the expected 1/16, based on two recessive genes (ps2, path2). In F3 and following generations part, if not all the plants or lines fspk, were lost. Only a few successfully achieved F6. This indicates that for seedless plants, some gene or genes are lacking for fully parthenocarpic expression under all environmental conditions. Since low numbers or no fspk plants were found in F2, the fs plants were self-pollinated; sometimes the fspk plants or even the lines were found in F3. However, sometimes plants or fspk lines of F3 are not found, and some of these plants or lines were lost in a higher generation. Due to the instability of the fspk plants of F2, the cross-links on the lines or F3 plants were carried out. In F2 or F3 of this backcross no plants or fspk lines were found, depending on the recurrent parent.

Despite large numbers (200 F2 plants) and the use of all fs plants in F2, no fspk plants were found in F2 or F3 from one of the progenitors of the Fl Durinta hybrid. Meanwhile, a progenitor Fl India gives in each F2 of a backcross plants fspk.

Work on seedless lines Starting from the aforementioned lines, a number of different progenitor lines containing the pk complex, fs (indicated 1 to 9 and 11 to 16) were developed. These were crossed to provide a seedless, hybrid Fl, and the fruit without seed and the quality of the fruit were also determined. The results are as follows: TABLE 1 - PERCENTAGE OF PRODUCTION OF PARTENOCARPIC FRUITS AND PERCENTAGE OF GOOD FRUITS, COMPLETELY DEVELOPED - ALL LINES USED ARE FSPK LINES It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (18)

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. A method for producing a tomato without seed, a plant that gives tomatoes without seed, or capable of giving tomatoes without seed, or the cultivation material for such a tomato plant, such as seed, characterized the method because it comprises the steps of: to. the provision of a first tomato plant containing the pk complex, fs (for example a first progenitor pk, fs); b. the provision of a second tomato plant containing the pk complex, fs (for example a second progenitor pk r fs); c. the crossing of the first and second tomato plants for the production of culture material, such as the seed, which contains the pk r fs complex; d. optionally culturing the culture material obtained in this way, in a tomato plant capable of giving tomatoes without seed; and. optionally develop the tomato plant until it gives the tomatoes seedless, and harvest the seedless tomatoes obtained in this way.

2. The method according to claim 1, characterized in that it comprises the steps of: a. the provision of a first tomato plant containing the pk complex, fs, which is also homozygous dominant with respect to at least one property desired for the production of tomatoes; b. the provision of a second tomato plant containing the pk complex, fs, which is also homozygous recessively with respect to at least one desired property for the production of tomatoes; c. the crossing of the first and second tomato plants for the production of culture material, such as the seed, which contains the pk complex, fs, and which is also heterozygous with respect to at least one property desired for the production of tomatoes; d. optionally culturing the culture material obtained in this manner in a tomato plant capable of yielding seedless tomatoes; and. optionally develop the tomato plant until it gives the tomatoes seedless, and harvest the seedless tomatoes obtained in this way.

3. The method for the provision of a hybrid tomato plant capable of yielding seedless tomatoes, or the seed or other culture material for such a hybrid tomato plant, characterized in that the method comprises at least one step of pollinating a first tomato plant without seed in which the seedless phenotype is due to the presence of an essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, of which at least two factors provide the first tomato plant without seed, with some phenotypic properties of parthenocarpy and at least two factors provide the first seedless tomato plant with some phenotypic properties of functional sterility; with the pollen obtained from a second seedless tomato plant in which the seedless phenotype is due to the presence of an essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, of which at least two factors provide the tomato plant with some phenotypic properties of parthenocarpy, and at least two factors provide the tomato plant with some phenotypic properties of functional sterility, and in which the phenotypic properties of parthenocarpy and functional sterility contribute to the total seedless phenotype of the tomato plant.

4. The method according to claim 3, characterized in that the pollination of the first seedless tomato plant with the pollen from the second tomato plant involves the steps of opening - preferably manually - the closed pollen tube of the second tomato plant; remove - preferably manually - the pollen from the pollen tube of the second tomato plant; and / or applying - preferably manually - the pollen to the pistil of the first tomato plant.

5. A method according to claim 3, characterized in that the first and second seedless tomato plants belong to inbred lines, preferably to two different inbred lines.

6. The method according to claim 3, characterized in that it comprises the additional steps of allowing the first seedless tomato plant fertilized in this way to form fruits containing the hybrid seed, and the hybrid seed of the fruits is harvested; and optionally comprising the additional steps of growing a generation of seedless hybrid tomato plants from the hybrid seed, allowing seedless hybrid tomato plants to bear fruit (for example, seedless tomatoes), and seedless tomatoes are harvested.

7. The seed for a hybrid tomato plant, characterized in that it is capable of yielding seedless tomatoes obtained via the method according to claim 6, or by cultivating the material obtained from the seed, such as the seedlings.

8. The hybrid tomato plant, characterized in that it is capable of giving tomatoes without seed, obtained via the method according to claim 6.

9. The seedless tomato, characterized in that it is obtained as the fruit from the hybrid tomato plants according to claim 8.

10. Processed products, in particular processed food products, characterized in that they are obtained from or using, or contain, a seedless tomato according to claim 9.

11. The tomato plant with a seedless phenotype, characterized in that the seedless phenotype is due to the presence of an essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, of which at least two provide the tomato plant with some phenotypic properties of parthenocarpy and at least two provide the tomato plant with some phenotypic properties of functional sterility, and in which the phenotypic properties of parthenocarpy and functional sterility contribute to the phenotype without complete seed, of the plant of tomato.

12. The tomato plant with a seedless phenotype according to claim 11, ! characterized because the plant belongs to an inbred line.

13. The tomato plant with a seedless phenotype according to claim 11, characterized in that the plant is a hybrid.

14. The use of a tomato plant with a seedless phenotype, in which the seedless phenotype is due to the presence of an essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, which at least two provide the tomato plant with some phenotypic properties of parthenocarpy, and at least two provide the tomato plant with some phenotypic properties of functional sterility, in which the phenotypic properties of parthenocarpy and functional sterility contribute to the seedless phenotype complete tomato plant; as a progenitor plant to obtain the hybrid progeny without seed.

15. A method to maintain a tomato plant with a seedless phenotype, in particular -for the maintenance of an inbred line of such tomato plants, and / or to obtain the seed or other cultivation material for such plant or line, characterized in the method because it comprises at least one step of pollinating a tomato plant with a phenotype seedless in which the seedless phenotype is due to the presence of an essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, of which at least two factors provide the first tomato plant seedless with some phenotypic properties of parthenocarpy, and at least two factors provide the first seedless tomato plant with some phenotypic properties of functional sterility; with pollen obtained from the same plant, or with pollen from another plant that belongs to the same inbred line.

16. The method according to claim 15, characterized in that the pollination of the first seedless tomato plant with the pollen from the second tomato plant involves the steps of opening - preferably manually - the closed pollen tube of the second tomato plant; remove - preferably manually - the pollen from the pollen tube of the second tomato plant; and / or applying - preferably manually - said pollen to the pistil of the first tomato plant.

17. The method according to claim 15, characterized in that it comprises the additional steps of allowing the seedless tomato plant fertilized in this way to form fruits containing the seed, and the seed of the fruits is harvested; optionally further comprising the steps of growing an additional generation of seedless tomato plants from said seed.

18. The method according to claim 3, characterized in that the essentially recessive complex of at least 4, preferably at least 5, more preferably at least 6 genetic factors, comprises at least the genes pat-2 and ps-2, as well as at least 2, preferably at least 3, more preferably at least 4 additional genes, more preferably such that the pat-2 gene and at least one, preferably at least two, additional genetic factors provide the tomato plant with some phenotypic properties of parthenocarpy, and so that the ps-2 gene and at least one, preferably at least two additional genetic factors provide the tomato plant with some phenotypic properties of functional sterility, in which the phenotypic properties of parthenocarpy and functional sterility contribute to the phenotype without Complete seed of the tomato plant. -, -