SU1729338A1 - Method for apple-tree reproduction in tissue culture - Google Patents

Abstract

The invention relates to agriculture, in particular to the primary seed production of corn hybrids obtained on a sterile basis. The purpose of the invention is to increase the efficiency of the method by reducing the primary seed production stage. For this purpose, assessment and selection are simultaneously carried out according to the fixative, restorative, combination abilities and completeness of cytoplasmic male sterility (CMS) by taking into account the parameters of two combinations of crosses. In this case, the cob of a sterile form is divided into two parts, each half is isolated separately. One half is pollinated by fertility pollen pollen. The resulting progeny are self-pollinated. 1 tab. cl

Description

The invention relates to the seed production of agricultural crops and can be used in the primary seed production of parental forms of corn hybrids obtained on a sterile basis.

Growing seeds at hybridization sites is associated with significant labor and money costs for tearing off panicles in maize plants. However, the creation of maize forms with cytoplasmic male sterility (CMS) and their use as maternal on hybridization sites excludes tearing of panicles. The form of corn with CMS is widely used in the world practice of primary seed production. The peculiarity of this type of sterility is expressed in the fact that when crossing plants with sterile pollen, with some selected or created normally flowering plants, progeny are obtained with sterile panicles. With further repeated saturating crosses with the same fertile (flowering) forms, the sign of sterility can be transmitted to offspring for many generations.

However, not all self-pollinated lines, when crossed with sterile plants, give similar results.

By the action on the sterile forms, they are divided into (1) sterility enhancers, the use of which in crosses with sterile plants gives only sterile progeny.

Repeated saturation crosses with sterility fixers for 5-6 generations and selection according to the type of the initial form allows to obtain sterile analogues of these forms; (2) fertility reducing agents that, when crossed with sterile VJ

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These plants produce offspring with fertile (flowering) panicles with viable pollen.

The traditional method of creating sterile analogues is known. The methodological instructions describe in detail the full cycle of primary seed production for the selection of maize for fixing, restoring, completeness of CMS and combining ability of lines.

However, the method of producing hybrid corn seeds has a number of significant drawbacks: it takes 6 or more years to complete a cycle of assessing the fixative, restorative, combination capacity and completeness of sterility by the method of periodic selection; testing the fixative and restorative ability of the parental forms is carried out with respect to different seven maternal components and does not allow simultaneously controlling these properties with respect to complete siblings within the family; the traditional method does not imply simultaneous individual control of the parameters of the CMS and combining ability.

The purpose of the invention is to increase the efficiency of the method by reducing the stages of primary seed production.

This goal is achieved by the fact that, according to the method of primary seed production, maize hybrids, including the assessment of parental forms for anchoring, restoring, completeness of cytoplasmic male sterility (CMS) and combining ability, by reducing the primary seed stage, all the indicators are evaluated simultaneously two combinations of crosses, obtained by pollination of one sterile cob with pollen of the sterilizer analogue and the restorer, fertile the spines of their immersion of the resulting offspring of fertile forms. In this case, two combinations of crossing are obtained by dividing the cob of a sterile form into two parts and isolate each half separately.

A comparative analysis with the prototype allows us to conclude that the proposed method differs from the well-known one in that the selection for fixative, restorative, combining ability and completeness of CMS is carried out simultaneously.

In the proposed method of selection for fixative, restorative, combining ability and completeness of sterility, a new property of a selection-valuable trait is attached and applied for a new purpose (selection by traits is carried out both interlinear and intra-seed, which is achieved as a result of two combinations of crossing on one maternal plant).

The method is carried out as follows.

In the first year of work, in the field conditions, 500 plants of the analogue of sterility fixers and 500 plants of the paternal fertility restorer line are selected. Selected forms of one part of the pollen are self-pollinated, while the other is crossed with a sterile form. In this case, each mother plant is simultaneously applied with pollen from an analogue of the fixative and a fertility restorer line, i.e. two combinations are obtained on each sterile plant: 1. Aster, x Azacr. Ster .; 2. Aster, x Avostst.

Two technical solutions can be used to produce two combinations of crosses on each individual sterile plant.

The essence of the first approved original technique is to get two combinations of crosses on one cob. For this, during the mass isolation period, the cob of a sterile form is cut vertically from top to bottom into two parts using a scalpel. Each half of the cob is carefully and gently insulated with polyethylene insulators. After 3-4 days, one half of the cob of the sterile maternal form is pollinated with pollen from the sterility fixative analogue, and the other part - with fertilizer restorer pollen.

The essence of the second method is as follows.

The first and second cob can be used to produce two combinations of crosses on each sterile maternal plant. The use of two cobs for crossing in the seventies was successfully used by US specialists to create simple maize hybrids. At the same time, the genetic identity of the first and second cob was confirmed, as regards the quality of seeds.

Thus in the first year of work receive 500 quartets. 1. Azakr .; 2. In the east; 3. Aster, x In.; 4. Aster, x Azakr. Each quartet is clearly recorded with numbers.

In the second year, 30-50 grains are taken from each of the received cobs, sown in separate rows and an assessment of complete sterility, fixative and restorative ability is carried out. If necessary, the Acer combination. x Highlighting at the same time can be used to control the combining ability. Non-compliant samples are discarded.

For the third year, the remnants of seeds from the Azacr self-pollination. and vvost. propagated in isolated plots and once again rejected rejected variety samples.

Consequently, in the proposed method, the full cycle of periodic selection of all the above parameters is carried out over 3 years, which reduces the time for carrying out the selection work twice.

The method can be used in the primary seed production of almost all known types of maize hybrids grown on the basis of CMS. A particularly significant effect of the proposed method can be achieved in seed production of the most common at present three-line hybrids and, in particular, when controlling the CMS parameters of a simple maternal sterile Aster hybrid, x Acacr.

The comparative effectiveness of the periodic selection of corn varieties for the proposed method is given in the table.

The table shows that in the proposed method almost all types of technical operations for the selection of parental forms of corn on CMS spend the first two years in

Compared with the prototype, in which you need 5 liters. In the third year in the proposed method and in the sixth year, the reproduction of the separated families with simultaneous rejection is carried out in the base year.

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Claims (2)

1. The method of primary seed corn hybrids, including the assessment of parental forms for fixative, restorative, combination the ability and completeness of CMS, characterized in that, in order to increase the efficiency of the method by reducing one stage of primary seed production, the assessment of the parental forms in all indicators It is carried out simultaneously, taking into account the parameters of two combinations of crosses, obtained by dusting one sterile cob with the pollen of the sterilizer analogue and the reducing agent fertility and subsequent self-pollination of the resulting offspring of fertile forms. 2. A method according to claim 1, characterized in that the two crossing combinations are obtained by dividing the cob of a sterile form into two parts, each half being isolated separately. Seed production by year Base object (prototype) The proposed method Selection of 500 plants of the fixer (Azakr.) Followed by self-pollination and crossing with a sterile analogue (Aster.) Study of couples by reaction to CMS and other economic characteristics, rejection of variety samples not corresponding to the purpose. Reproduction of families in an isolated area with simultaneous rejection Selection of 500 plants of fertility restorer (Vvost), followed by self-pollination and crossing with a sterile analogue (Aster.). Radiation of pairs according to the reaction on CMS according to the combining ability and other characteristics, rejection of variety samples. Reproduction of the selected seeds, rejection of variety samples. Selection of 500 plants of the fixer (Azakr.) And 500 plants of the reducing agent (Avost.), Followed by self-pollination and crossing with a sterile analogue (Aster.) Study of quartets by reaction to CMS, combining ability and other intrinsic traits, rejection of non-appropriate variety of samples. Reproduction of the isolated families of the reducing agent, sterile form and analogue of the sterility fixer with simultaneous rejection