CN-122004121-A - Method for purifying and breeding three-line sterile line of hybrid rice by regeneration method

CN122004121ACN 122004121 ACN122004121 ACN 122004121ACN-122004121-A

Abstract

The invention relates to the technical field of rice heterosis utilization, in particular to a method for purifying and generating three-line sterile lines of hybrid rice by a regeneration method. The invention aims at the condition that the purity of the three-line sterile line of hybrid rice is reduced after multi-generation propagation, so that the purity is lower than 99.5 percent and does not reach the standard, and adopts a regeneration method to quickly purify and propagate the sterile line. The method has the advantages of simple operation, short period and good purification effect, can obviously improve the purity of the sterile line, obtain a sufficient amount of seed sources and meet the requirements of hybrid seed production.

Inventors

PENG JIALIANG
HUANG LUYAO
TONG SHAN
Ye Xiaoniu
LIAO ZHIQIANG
WU PING
CHEN WENHONG
LIU YING
ZENG LONGJUN
Tan Chenju
ZHANG CHAO
XIONG XIANGYU
ZOU YUJING
YANG HAIPING

Assignees

宜春市科学院(江西富硒产业研究院)

Dates

Publication Date: 20260512
Application Date: 20260318

Claims (8)

1. The method for purifying and generating the three-line sterile line of the hybrid rice by using the regeneration method is characterized by comprising the following steps of: S1, seeding and raising seedling in a seedling bed, namely seeding the sterile line A and the maintainer line B into the seedling bed, and raising strong seedlings; s2, transplanting, namely when the seedling leaf age reaches 5.1 leaves to 5.8 leaves, lifting seedlings from the seedling bed, and transplanting the seedlings to the Honda; S3, removing impurities for the first time, namely removing non-self variety hybrid plants in the sterile line A and the maintainer line B according to the shape and the leaf color difference of plant leaves from the transplanted field to the 5 th-6 th stage of young spike differentiation; S4, performing second impurity removal and first crop green cutting treatment, namely, not spraying gibberellin in the initial ear period to the ear alignment period of the sterile line A and the maintainer line B, identifying and removing the impurity plants which do not cover the neck and have different agronomic characters from the sterile line A in the line A of the sterile line A by utilizing the neck covering phenomenon of the sterile line A, and simultaneously removing the impurity plants in the line B of the maintainer line according to the agronomic character difference; s5, promoting regeneration, namely after green cutting, ensuring that the field has a water layer of 4 cm-5 cm so as to promote rice stubble regeneration; S6, managing regenerated seedlings and removing impurities for the third time, namely, when 50% -60% of the sword leaves of the regenerated sterile line A and the sword leaves of the maintainer line B grow, fertilizing, and pulling out the impurity plants of the leaky net according to the plant leaf shape and She Secha; s7, flowering phase regulation and gibberellin spraying: when the sterile line A is exposed to 20% -30%, gibberellin is sprayed on the sterile line A, wherein the dosage of each 666.7m 2 is 10-12 g; secondly, when the heading of the regenerated sterile line A reaches 40% -50%, gibberellin is sprayed to the regenerated sterile line A and the regenerated maintainer line B simultaneously, wherein the dosage of each 666.7m 2 is 10-12 g; thirdly, after the second spraying for 1 day, only gibberellin is sprayed on the regenerated maintainer line B, wherein the dosage of each 666.7m 2 is 4g; S8, artificial supplementary pollination and male parent cleaning, namely, pollinating the pollen of the regenerated maintainer line B to the regenerated sterile line A through artificial assistance in the flowering stage of the regenerated maintainer line B, and after the pollination stage is finished, cutting all the regenerated maintainer line B and cleaning out the field; s9, harvesting and preserving purity, namely harvesting and airing the hybrid seeds on the sterile line A after the hybrid seeds are mature.
2. The method according to claim 1, wherein the maintainer line B is sown in two stages in S1, the first stage is denoted as maintainer line B1 and the second stage is denoted as maintainer line B2, and the maintainer line B1 is sown 4 to 5 days later than the sterile line A and the maintainer line B2 is sown 6 to 7 days later than the sterile line A.
3. The method according to claim 1, wherein the seeding rate of the sterile line A in S1 is 1kg/666.7m 2 and the seeding rate of the maintainer line B is 0.5kg/666.7m 2 .
4. The method according to claim 1, wherein the specifications of transplanting in S2 are: Sterile line A is single plant, 1 plant in each hole, plant row spacing 13.3cm x 13.3cm; the maintainer line B is that 1-2 plants can be planted in each hole, and the row spacing of the plants is 13.3cm multiplied by 16.7cm; the row ratio is configured that the row ratio of the maintainer line B to the sterile line A is 2:7-8; the row spacing between the maintainer line B and the sterile line A is 16.7cm.
5. The method of claim 1, wherein the method of identifying hybrid plants using the cervical covering phenomenon of sterile line A in S4 is characterized in that sterile line A is shown to be cervical covering without spraying gibberellin, while maintainer lines or other hybrid plants mixed in line A of sterile line A are shown to be non-cervical covering, the non-cervical covering plants grow more vigorously, have higher height and the male flowers scatter than the cervical covering plants, and simultaneously, the hybrid plants in line B of maintainer lines are identified and removed according to agronomic trait differences.
6. The method according to claim 1, wherein when the sterile line A and the maintainer line B are cut in S4, the cutting height is 2 cm-3 cm from the neck of the main spike.
7. The method of claim 1, wherein the artificial supplementary pollination in S8 is performed by shaking the maintainer line B with bamboo poles to allow pollen to float to the sterile line a 2-3 times per day during flowering.
8. The method of claim 1, wherein the sterile line A comprises Wufeng A or Yexiang A and the maintainer line B comprises Wufeng B or Yexiang B.

Description

Method for purifying and breeding three-line sterile line of hybrid rice by regeneration method Technical Field The invention relates to the technical field of rice heterosis utilization, in particular to a method for purifying and generating three-line sterile lines of hybrid rice by a regeneration method. Background The current hybrid rice is rapidly developed, the number of new examined varieties is increased year by year, the requirements of rice growers on the quality of rice seeds are higher and higher, and the requirements of production units on the purity and the number of three-line sterile lines of the rice are also continuously improved. In the production of three sterile lines of hybrid rice, a brief production process is generally adopted, namely, breeding of three sterile line stock seeds of hybrid rice, propagation of sterile line stock seeds, propagation of sterile line by adding generations, purification and rejuvenation by multi-nursery system and propagation of sterile line. In actual production, the production unit needs to propagate the provided stock to meet the production requirement. In order to meet the quantity of sterile line seeds required by the first generation of hybrid seeds, the production unit is continuously added with generation and reproduction, and in each generation and reproduction production process, the purity of the sterile line seeds is reduced due to the following reasons, such as mechanical mixing caused by harvesting, airing and the like, falling of paddy rice in the season, mixing of maintainer lines, biological cross-breeding of hybrid plants and the like. Along with the increase of production algebra, the purity of the sterile line is continuously reduced, so that the sterile line does not reach the standard (the purity of seeds is less than 99.5%). However, the three-line sterile line of the rice has a need in production, and the sterile line is purified by a multi-nursery method in the past. However, the production technology of multi-nursery production is strong, the period is long, the obtained seeds are limited in quantity, and the demand and supply are easy to be disjointed. Therefore, development of a method for rapidly improving the purity of three sterile lines of hybrid rice and increasing the number of seeds of the sterile lines is needed. Disclosure of Invention In order to solve the problems, the invention provides a method for purifying and breeding three-line sterile lines of hybrid rice by using a regeneration method. The invention is realized by the following technical scheme: a method for purifying and breeding three-line sterile lines of hybrid rice by a regeneration method comprises the following steps: S1, seeding and raising seedling in a seedling bed, namely seeding the sterile line A and the maintainer line B into the seedling bed, and raising strong seedling. S2, transplanting, namely when the seedling leaf age reaches 5.1 leaves to 5.8 leaves, lifting the seedling from the seedling bed, and transplanting the seedling to the Honda. S3, removing impurities for the first time, namely removing non-self variety hybrid plants in the sterile line A and the maintainer line B according to the shape and the leaf color difference of plant leaves from the transplanted field to the 5 th-6 th stage of young spike differentiation. S4, performing second impurity removal and first crop green cutting treatment, namely, not spraying gibberellin in the initial ear period to the ear alignment period of the sterile line A and the maintainer line B, identifying and removing the impurity plants which do not cover the neck and have different agronomic characters from the sterile line A in the sterile line A row by utilizing the neck covering phenomenon of the sterile line A, simultaneously removing the impurity plants in the maintainer line B row according to the agronomic character difference, and cutting all the sterile line A and the maintainer line B after impurity removal. S5, promoting regeneration, namely after green cutting, ensuring that the field has a water layer of 4 cm-5 cm so as to promote rice stubble regeneration. S6, managing regenerated seedlings and removing impurities for the third time, namely, when 50% -60% of sword leaves grow out of the regenerated sterile line A and the maintainer line B, fertilizing, and removing the impurity plants of the leaky net according to the agronomic character difference. S7, flowering phase regulation and gibberellin spraying: when the exposure of the regenerated sterile line A is 20% -30%, gibberellin is sprayed on the regenerated sterile line A only, and the dosage of each 666.7m 2 is 10-12 g. And secondly, when the heading of the regenerated sterile line A reaches 40% -50%, gibberellin is sprayed to the regenerated sterile line A and the regenerated maintainer line B simultaneously, wherein the dosage of each 666.7m 2 is 10-12 g. And thirdly, after 1 day of spraying for the second time, spraying gibber