CN107896976B

CN107896976B - Breeding method for fixing heterosis of apomixis of special rice

Info

Publication number: CN107896976B
Application number: CN201711288920.8A
Authority: CN
Inventors: 郭咏梅; 邵源梅
Original assignee: Yunnan Nabaichuan Agricultural Technology Co ltd
Current assignee: Yunnan Nabaichuan Agricultural Technology Co ltd
Priority date: 2017-12-07
Filing date: 2017-12-07
Publication date: 2020-09-04
Anticipated expiration: 2037-12-07
Also published as: CN107896976A

Abstract

The invention discloses a breeding method for fixing heterosis of apomixis of special rice, which comprises the following specific procedures: propagating the rice apomixis germ line; selecting parents; hybridizing the selected parents; harvesting the asexual seeds of the special rice, respectively sowing the seeds in a combined mode, transplanting the seeds in a single plant, harvesting the seeds in the combined single plant when the seeds are mature, threshing the seeds, bagging and storing the seeds; screening special rice non-fusion bodies with high quality, high yield and multiple resistance; and (5) performing variety comparison. The Yungui purple No. 1 hybrid rice new variety bred by the technology is a purple soft rice hybrid rice new variety, and has excellent taste and nutritional quality, good high yield, good resistance and wide adaptability; yungui purple No. 2 is a new variety of purple soft rice hybrid rice, and has excellent taste and nutritional quality, good yielding property and good resistance. The indica rice can be planted in an indica rice area and an indica japonica rice staggered area below the elevation 1600 meters in Yunnan, and the yield is increased by 40-50% compared with the average yield of the conventional special rice, namely the Mojiang purple rice.

Description

Breeding method for fixing heterosis of apomixis of special rice

Technical Field

The invention relates to the field of plant variety breeding, in particular to a breeding method for fixing heterosis of apomixis of special rice.

Background

The utilization of the first generation heterosis is an effective way for increasing the yield of crops, but the separation of characters or fertility occurs in multiple generations after the first generation of the hybrid, so that the seeds are required to be bred every year, a lot of manpower and material resources are wasted, and the utilization of apomixis to fix the heterosis is expected by many breeders. In our country, Zhao world has first proposed the idea of fixing rice heterosis by apomixis. In 1987, a strategic assumption is made on rice heterosis utilization by famous hybrid rice breeders Yuanyin: namely, the sequence of the utilization method is a three-line method, a two-line method and a one-line method, and the one-line method is to utilize apomixis to fix heterosis. Subsequently, the basic conditions, the breeding material steps and the research stage of fixing the heterosis by utilizing apomixis are definitely proposed by the caide field, the chenopodium pubescens, the Zhouyida and the like. Through years of research, China has not only bred various apomictic rice materials, such as ASR-1, C1001, HDAR, SB-1, CYAR-2 and the like, but also discovered diploid apomictic phenomena such as adventitious embryogenesis, polyblastula, apomictic reproduction and the like through embryology observation, and lays a good foundation for breeding apomictic rice strains suitable for fixing heterosis.

Southwest juncture of China at southwest, up to 4060 km long, is adjacent to southern, Laos and Burma of the main countries of rice in the world, has superior natural conditions, various ecological types and rich resources, is the origin of artificial cultivated rice and is the starting point of rice spreading. Due to various ecological types and rich rice seed resources, the number of rice varieties is at the first of the whole country, although the rice varieties are not the big provinces of rice production, the rice varieties can be called as high-quality rice big provinces, and the rice covering, the Babaogong, the crouchong, the Maojiang purple rice, the terrace red rice and the like are sold well and saved inside and outside, due to the rich and colorful minority rice culture and dietary habits, rare special rice seed resources are protected, and resources and humanistic advantages are provided for the development of special and special rice.

The special rice such as Yunnan soft rice, glutinous rice, purple rice, red rice and the like is high in planting regionality and cannot be copied, is a good food material for developing special rice and rice products with nutrition and functions, has wide development prospect, is a rare germplasm resource for developing colored rice, is rich in protein, amino acid, vegetable fat, cellulose and mineral substances necessary for human bodies, such as Fe, Zn, Ca and the like, and is rich in vitamins B1, B2, B6, B12, D, E and nicotinic acid, and particularly contains vitamin C and carotene which are lacked by common rice. In addition, the pigment in the colored rice bran is proanthocyanidin or anthocyanin, which belongs to flavonoid substances, can be used as a safe natural pigment to be used as a food additive, and has special physiological active ingredients. However, the special rice is scattered in planting and small in scale, and is mainly distributed in hot areas with inconvenient transportation and numerous minority nationalities, such as partial counties of Dehong state, Xishuangbanna state, Wenshan state, Chuxiong state and Honghe state. The local special rice has poor plant type, easy dumping, low yield, poor disease resistance, and excellent taste quality and nutrition quality, and the rice seed resources can be preserved due to the dietary habits of minority.

With the continuous improvement of living standard of people, people have more and more high requirements on rice varieties because people eat less and more green products, and the new variety of special rice with high quality, high yield and multiple resistance is the current breeding target. Because the quality and yield of rice varieties relate to quantitative traits, although the disease and insect resistance belongs to dominant traits, different resistances or the same resistance belongs to different gene loci, and the separation of the hybrid generations caused by meiosis causes that the pure line breeding method is difficult to integrate the characteristics of high yield, high quality and multiple resistance. The apomixis has the characteristics of heterozygous genotype and consistent phenotype, and is beneficial to accumulating high-quality, high-yield and multi-resistance genes at different sites in a heterozygous state, so that the breeding target is achieved. Therefore, by combining apomixis with genes such as high yield, high quality, disease resistance and the like, a new high-quality, high-yield and multi-resistance special rice variety is bred, a new way for rapid breeding of special rice is provided, the utilization of precious special rice germplasm resources is accelerated, and the method has great significance for developing high-quality special rice.

Disclosure of Invention

The invention aims to provide a breeding method for fixing heterosis of special rice apomixis, so as to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme:

a breeding method for fixing heterosis of apomixis of special rice comprises six procedures, and the specific procedures are as follows:

1) breeding the rice apomixis germ line: propagating genetic material 12-G555 with fixed heterosis characteristics;

2) selecting parents, wherein one of the two parents is a facultative apomixis line which is required to be selected as a parent for hybridization, and breeding a rice sexual reproduction variety with high quality, high yield, good resistance and high combining ability and a rice facultative apomixis line which is required to be selected as a parent for hybridization;

3) hybridizing the selected parents to obtain special rice hybrid seeds containing apomixis genotypes;

4) harvesting the asexual seeds of the special rice, respectively sowing the seeds in a combined mode, transplanting the seeds in a single plant, harvesting the seeds in the combined single plant when the seeds are mature, threshing the seeds, bagging and storing the seeds;

5) screening special rice non-fusion bodies with high quality, high yield and multiple resistance;

6) performing variety comparison, and breeding a high-quality, high-yield and multi-resistance apomixis special hybrid rice variety;

the 12-G555 is a facultative apomixis line, the pistil of the sexual reproductive line can accept pollen, and the pollen of the sexual reproductive line is viable, so that the sexual reproductive line can be used as a female parent and a male parent to be hybridized with other sexual reproductive varieties to obtain hybrid seeds. Hybridizing the selected parents with 12-G555, and performing positive and negative crossing to obtain the rice hybrid containing the apomixis genotype, for example, performing tassel trimming and castration on the female parent facultative apomixis line 12-G555 one day before flowering, sleeving a hybrid paper bag with the male parent sexual reproduction variety R808 spike after castration, knocking the hybrid paper bag with fingers for pollination when midday rice is full-flowering, knocking for 3 days continuously, and harvesting the hybrid seed containing the apomixis of the rice 12-G555 multiplied by R808 after maturing. Or emasculating the whole spike one day before the female parent sexual reproduction variety L20 blooms, sleeving a hybrid paper bag together with the male parent facultative apomictic line 12-G555 spike after emasculation, knocking the hybrid paper bag with fingers for pollination when the midday rice is full of flowers, knocking for 3 days continuously, and harvesting the hybrid seed L20 x 12-G555 containing the rice apomictic after maturity;

respectively sowing the hybrid seeds such as 12-G555 multiplied by R808 and L20 multiplied by 12-G555 obtained above according to combinations, transplanting the individual plants, observing a generation of hybrid plants different from the parents R808, L20 and 12-G555 in the field, selecting a combination with obvious hybrid vigor and ultrahigh affinity, and respectively harvesting, threshing and bagging the hybrid plants according to the combination of the individual plants when the hybrid plants are mature;

sowing the harvested hybrid first generation (F1) seeds in a combined manner, transplanting the seeds into single plants, observing that no-separation plant groups appear in the hybrid second generation (F2) plants in the field, and obtaining non-fusion bodies with fixed hybrid vigor, wherein the non-separation plant groups have regular and consistent field agronomic characters, and the non-fusion bodies are respectively mixed and harvested, threshed, numbered and bagged for storage according to the combination;

sowing and transplanting the hybrid second generation (F2) seeds obtained by mixed harvest according to combination, performing field investigation during the growth period of the hybrid third generation (F3) non-fusion bodies such as 12-G555 multiplied by R808 and L20 multiplied by 12-G555, sampling and testing seeds, counting the data, screening special hybrid rice varieties with excellent quality, high yield and good resistance by taking special rice such as Mojiang purple rice and the like as reference seeds, and setting the varieties as Yungui purple No. 1 and Yungui purple No. 2. The special hybrid rice varieties do not need to be produced year by year, can be utilized for multiple generations, and have the characteristics of good high yield, excellent rice quality, good resistance, wide adaptability and the like.

As a further scheme of the invention: the apomixis line 12-G555 is used as material to breed asexual seeds, because the apomixis is carried out before the blooming of 12-G555, hybrid seeds can be obtained through artificial forced pollination, and the apomixis is carried out under natural conditions at the later stage of blooming to produce asexual seeds, and the color of seed coats is purple. Therefore, the facultative apomixis 12-G555 seed is sown in the middle 3 months, the single plant is transplanted at the beginning of 5 months, and the purple asexual seed is harvested at the end of 8 months when the plant is mature.

Compared with the prior art, the invention has the beneficial effects that: the invention selects special rice varieties with special qualities of fragrance, taste, nutrition and the like as parents by utilizing the rice apomixis line, selects special rice non-fusion bodies, performs variety comparison, and breeds the apomixis hybrid rice varieties with high quality, high yield and multiple resistance. The problems of low yield, poor disease resistance and strong regionality of special rice are solved, and the breeding period is shortened by over 2/3; the Yungui purple No. 1 hybrid rice new variety bred by the technology is a purple soft rice hybrid rice new variety, and has excellent taste and nutritional quality, good high yield, good resistance and wide adaptability; yungui purple No. 2 is a new variety of purple soft rice hybrid rice, and has excellent taste and nutritional quality, good yielding property and good resistance. The indica rice can be planted in an indica rice area and an indica japonica rice staggered area below the elevation 1600 meters in Yunnan, and the yield is increased by 40-50% compared with the average yield of the conventional special rice, namely the Mojiang purple rice. Drawings

FIG. 1 is a schematic structural diagram of Yungui purple No. 1 breeding in a breeding method for fixing heterosis of special rice apomixis.

FIG. 2 is a schematic structural diagram of Yungui purple No. 2 breeding in a breeding method for fixing heterosis of special rice apomixis. Detailed Description

The technical solution of the present patent will be described in further detail with reference to the following embodiments.

Example 1

Referring to fig. 1, a hybrid seed is obtained by crossing a rice sexual apomixis line 12-G555 as a female parent and a high-quality soft rice sexual reproduction variety R808 as a male parent. The heterosis of the first generation (F1) plant is obvious, the plant characteristics and biological characteristics of the individuals are completely the same (no fusion), the agronomic characters of the plants are different from those of the two parents, the high yield of the plants is higher than that of the high-value parents, the seed coat of the F1 selfed seed is purple, and the seeds are harvested, threshed and bagged for storage when the seeds are mature. Sowing the harvested seeds of the first generation (F1) of the hybrid, transplanting the seeds into a single plant, observing that the plants of the second generation (F2) of the hybrid have no separate plant group in the field, and obtaining the non-fusion body with fixed hybrid vigor, wherein the agronomic characters of the non-separation plant group are the same as or similar to those of the plants of the first generation hybrid, but are different from those of the two parents; and sampling and testing seeds when the seeds are mature, and harvesting and threshing the single plant, and numbering the plant. Sowing the seeds of the second generation (F2) of the hybrid harvested in a combined mode according to the number, transplanting the seeds individually, observing the population of the third generation (F3) of the hybrid in the field, if the agronomic characters are uniform, the botanical characteristics and the biological characteristics among individuals are completely the same (no fusion), the agronomic characters of the individuals are different from those of two parents, the high yield of the seeds not only exceeds that of the high-value parents such as R808, but also exceeds that of the control species such as black rice in the ink river; therefore, the hybrid third generation breeds the non-fusion purple soft rice hybrid rice variety 12-G555 XR 808 named Yungui purple No. 1.

The 12-G555 indica rice line is from Musulco, Africa, contains an apomictic reproductive gene, is planted in an indica rice region below 1400m in Yunnan, has the characteristics of compact plant type, strong regeneration force, strong tillering force and self-incompatibility, but has pollen viability during cross breeding. The plant height is 80-85 cm, the ear length is 18-20 cm, the number of effective ears is 10-12, the total number of main ears is 80-100, the setting rate is 80-85%, the thousand seed weight is 20-21 g, the leaves are dark green, the grains are purple black, the brown rice is dark purple, and the brown rice is resistant to rice blast and bacterial leaf blight. The detection result of the agricultural product quality supervision, inspection and test center of Ministry of agriculture shows that the taste and quality of rice is as follows: 13.6 percent of protein, 3.15 percent of crude fat, 17.5 percent of amylose, 40mm of glue consistency and 7.0 grade of alkali digestion value.

The R808 indica rice line has compact plant type, strong tillering force, wide adaptability, high and stable yield and medium grain-dropping property. The whole growth period is 150-155 days (changed along with different altitudes), the plant height is 90-95 cm, the ear length is 25-28 cm, 10-12 effective ears, the total number of main ears is 200-220, the maturing rate is 80-85%, the thousand kernel weight is 22-24 g, the leaves are light green, the grains are golden yellow, and the grains are semitransparent. The detection result of the agricultural product quality supervision, inspection and test center of Ministry of agriculture shows that the taste and quality of rice is as follows: 6.39 percent of protein, 18.4 percent of amylose, 30mm of glue consistency and 7.0 grade of alkali digestion value. The field is resistant to bacterial blight and rice blast, and is suitable for planting in indica rice regions below the elevation 1600m or indica-japonica rice staggered regions in our province.

Example 2

Referring to fig. 2, a high-quality fragrant glutinous sexual reproductive variety L20 is used as a female parent, and a rice facultative apomictic reproductive line 12-G555 is used as a male parent to be hybridized to obtain hybrid seeds. The first generation (F1) of hybrid has obvious heterosis, the plant characteristics and biological characteristics are completely the same (no fusion) between individuals, the agronomic characters are different from those of the two parents, the high yield exceeds that of the high-value parents, the seed coat of the F1 selfing seed is purple, the rice quality is fragrant and soft, and the single plant is harvested, threshed and bagged for storage when the seed is mature. Sowing the harvested seeds of the first generation (F1) of the hybrid, transplanting the seeds into a single plant, observing that the plants of the second generation (F2) of the hybrid have no separate plant group in the field, and obtaining the non-fusion body with fixed hybrid vigor, wherein the agronomic characters of the non-separation plant group are the same as or similar to those of the plants of the first generation hybrid, but are different from those of the two parents; and sampling and testing seeds when the seeds are mature, and harvesting and threshing the single plant, and numbering the plant. Sowing the seeds of the second generation (F2) of the hybrid harvested in a combined mode according to the number, transplanting the seeds individually, observing the population of the third generation (F3) of the hybrid in the field, if the agronomic characters are uniform, the botanical characteristics and the biological characteristics among individuals are completely the same (no fusion), the agronomic characters of the individuals are different from those of two parents, the high yield of the seeds not only exceeds that of the high-value parents such as L20, but also exceeds that of the control species such as black rice in the ink river; therefore, a non-fusion purple soft rice hybrid rice variety L20X 12-G555 which is named as Yungu fixed purple No. 2 is bred in the third generation of the hybrid.

The L20 indica rice line has compact plant type, moderate tillering force, high and stable yield and moderate grain-dropping property. The whole growth period is 150-155 days (changed along with different altitudes), the plant height is 90-95 cm, the ear length is 20-25 cm, the number of effective ears is 8-10, the total number of main ears is 180-200, the maturing rate is 80-85%, the thousand-grain weight is 22-24 g, the leaves are light green, and the rice grains are milky white and have fragrance. The detection result of the agricultural product quality supervision, inspection and test center of Ministry of agriculture shows that the taste and quality of rice is as follows: 11.23 percent of protein, 5.91 percent of amylose, 100mm of glue consistency and 3.0 grade of alkali digestion value. The field is resistant to bacterial blight and rice blast, and is suitable for planting in indica rice regions below the altitude of 1400m in our province.

Although the preferred embodiments of the present patent have been described in detail, the present patent is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present patent within the knowledge of those skilled in the art.

Claims

1. A breeding method for fixing heterosis of special rice apomixis is characterized in that: the fixed special rice heterosis breeding method comprises six programs, and the specific programs are as follows:

wherein, the rice sexual reproduction variety with high quality, high yield, disease resistance and high combining ability is used as the hybridization parent, the special quality of fragrance, taste and nutrition is mainly considered, because 12-G555 is a facultative apomictic reproduction line, the pistil can accept pollen, the pollen of the pistil also has vitality, the rice hybrid containing the apomictic reproduction genotype can be used as a female parent and a male parent to be hybridized with other sexual reproduction varieties to obtain hybrid seeds, the selected parent is hybridized with 12-G555, and the male and female parents can be crossed to obtain the rice hybrid containing the apomictic reproduction genotype, the whole spike is castrated one day before the female parent facultative apomictic reproduction line 12-G555 blooms, the castration and the R808 spike of the male parent sexual reproduction variety are sleeved with a hybridization paper bag together after the castration, when the midday rice blooms are full, the hybridization paper bag is flicked by fingers to pollinate, the continuous knocking for 3 days, the hybrid seeds containing the rice apomictic reproduction 12-G555 xR 808 are harvested after maturity, or emasculating the whole spike one day before the female parent sexual reproduction variety L20 blooms, sleeving a hybrid paper bag together with the male parent facultative apomictic line 12-G555 spike after emasculation, knocking the hybrid paper bag with fingers for pollination when the midday rice is full of flowers, knocking for 3 days continuously, and harvesting the hybrid seed L20 x 12-G555 containing the rice apomictic after maturity;

respectively sowing the hybrid seeds 12-G555 multiplied by R808 and L20 multiplied by 12-G555 obtained in the above steps according to combinations, transplanting the individual plants, observing a generation of hybrid plants different from the parents R808, L20 and 12-G555 in the field, selecting a combination with obvious hybrid vigor and ultrahigh affinity, and respectively harvesting, threshing and bagging the hybrid plants according to the combination individual plants when the hybrid plants are mature;

sowing the harvested hybrid first generation F1 seeds in a combined manner, transplanting the seeds into a single plant, observing that no-separation plant groups appear in the hybrid second generation F2 plants in the field, and obtaining non-fusion bodies with fixed hybrid vigor, wherein the non-separation plant groups have regular and consistent field agronomic characters, and the non-fusion bodies are respectively mixed and harvested, threshed, numbered and bagged for storage according to the combination;

the hybrid second generation F2 seeds harvested by mixing are sown and transplanted in a combined mode, the non-fusion bodies 12-G555 xR 808 and L20 x 12-G555 of the hybrid third generation F3 are subjected to field investigation during growth, sampling and seed testing are carried out, statistical data are obtained, special hybrid rice varieties with excellent quality, high yield and good resistance are screened by taking the Mojiang purple rice special rice as a reference, and the special hybrid rice varieties are named as Yungunya purple No. 1 and Yungunya purple No. 2.

2. The breeding method for fixing heterosis of apomixis of special rice as claimed in claim 1, which is characterized in that: the facultative apomixis line 12-G555 is used as a material for propagating asexual seeds, because sexual reproduction is carried out before flowering of 12-G555, hybrid seeds can be obtained through artificial forced pollination, and apomixis is carried out under natural conditions in the later flowering period to generate asexual seeds, and the color of seed coats is purple, therefore, the facultative apomixis line 12-G555 is sowed in 3 middle ten days, single seedlings are transplanted in the early 5 months, and purple asexual seeds are harvested in single plants at the bottom of 8 months.