CN1110249C - Method for producing hybrid rice by perennial root method - Google Patents

Abstract

A method for producing hybrid rice by using perennial root method includes selection of sterile line and restoring line, and hybrid F₁And the production of hybrid rice; selecting sterile line GP8A or CP8A as female parent and the recovery line of the perennial root as male parent to compound perennial root hybrid F₁Reuse of perennial root hybrid F₁And (5) producing the perennial root hybrid rice. The invention has high yield, and the annual yield is at least increased by 20 percent compared with the current annual hybrid rice; the production cost of seeds is low, which is 40 percent lower than that of the existing annual hybrid; also utilizes perennial root F₁High efficiency of producing hybrid rice.

Description

Method for producing hybrid rice by perennial root method

The invention belongs to the technical field of rice heterosis utilization, and in particular relates to a method for breeding sterile lines and restorer lines by a perennial root method and producing perennial hybrid rice seeds and hybrid rice.

Rice in the world today is produced from one-year rice. Annual rice has been grown for about 10,000 years. Now the population is increasing and the rice fields are decreasing. In the past 30 years, high-yielding rice breeding has stagnated. It is almost hopeless to increase the per unit yield by 20% by existing technology. If there is no further increase in production, there will be a danger of food shortages.

Existing annual rice technical defect is:

1. To plant one-year-old rice, the paddy field must be plowed once a year or every season; seeds must be purchased and sown once a year or every season; rice is mainly transplanted in my country, and seedlings must be raised and planted every year or every season. These measures will consume a lot of human and financial resources.

2. Intensive cultivation for high yield is not only costly, but also induces minor pests and diseases that were insignificant decades ago to rapidly rise to serious pests and diseases in the past two decades, such as brown planthopper and the viral diseases it spreads. In order to prevent insect pests and fungal diseases induced by intensive cultivation, pesticides have to be applied heavily, which seriously pollutes the environment.

3. U.S. Patent No. 5158879 approved on October 27, 1992: Perennial CMS produces hybrid rice seeds, inventor Li Qinxiu. This patent produces annual hybrid rice seeds with ratoon sterile lines, but these ratoon sterile lines have lost their rhizome traits during the selection process and cannot be transplanted and rejuvenated automatically. Therefore, the perennial CMS must be manually transplanted and rejuvenated, otherwise it will degenerate into grass and have no use value. Make this patent can not put into production and utilize so far. In addition, the inventor Li Qinxiu has stopped providing the implementation technology to the U.S. side, so the patent that the U.S. side has most of the patent rights is invalidated in the U.S.

The purpose of the present invention is to provide a method for producing hybrid rice with the perennial root method, which uses the perennial root male sterile line to sow once and the perennial root for many years to continuously produce perennial root hybrid rice seeds. The rice plant grown after sowing the perennial root F ₁ hybrid seed can reproduce the heterosis through vegetative reproduction of the perennial root.

The present invention is achieved like this:

A method for producing hybrid rice using the ratoon method, comprising selection of sterile lines and restorer lines, production of hybrid _F1 and hybrid rice; selecting the ratoon sterile line as the female parent, selecting the ratoon restorer line as the male parent, and preparing the ratoon hybrid , and then use the perennial root hybrids to produce perennial hybrid rice.

The selected ratoon male sterile line is GP8A or male sterile line CP8A.

The selected sterile line is a completely non-photosensitive ratoon sterile line.

The selected ratoon restorer line is G4362 or P1839 measured from the existing conventional varieties; the restorer line can also be selected by crossing the existing restorer line with the ratoon system.

The hybrid F ₁ is a completely non-photosensitive perennial root F ₁ , which can reproduce heterosis for many years through asexual reproduction; it can continuously head and mature, harvest once a month, harvest _several times a year, and dormant until early winter.

For the hybrid F ₁ produced by the perennial root method, after mixed harvesting, the hybrid seeds were screened out according to the difference in grain width between the parents.

Advantage of the present invention and positive effect are as follows:

1. High output. There is no separate vegetative growth period for completely non-photosensitive perennial root hybrid rice, which can fully and effectively use light and hot water conditions to form rice yield. The perennial root paddy field harvests rice ears once a month, and harvests multiple times a year so that the total annual yield per mu is at least at least higher than that of the current annual hybrid rice. 20% increase. The yellow mature ear of perennial rice is 30-40cm higher than the unheaded ear, which is convenient for manual or mechanical harvesting and will not hurt the next batch of new ears.

2. The production cost of seeds is low. The vegetative reproduction of the perennial male sterile line has high purity and does not need to be impurity removed. When the completely non-photosensitive ratoon CMS line is combined with the early maturing ratoon restorer line, the hybrid seeds are harvested several times a year. The ratoon male sterile line has key characters such as long stigma and sparse panicle which are beneficial to outcrossing, and the outcrossing can reach 70%. Altogether, the cost of seed production is 40% lower than that of current annual hybrid rice.

3. The cost of using the perennial _F1 is low. The perennial root hybrid rice is reused as a seed pile, sowed once and harvested for 5 years, and no pesticides are used to treat diseases and insect pests. In some areas, less or no nitrogen fertilizer can be applied. Long-term no-tillage. All in all, substantial production costs can be saved.

4. Green manures such as perennial hybrid upland rice and perennial clover closely cover long-term no-tillage dryland slopes throughout the year, which can prevent soil erosion.

Specific embodiments of the present invention are as follows:

Example 1:

The present invention mainly includes three aspects: the breeding of the ratoon sterile line and the restorer line, the production of _F1 seeds by the ratoon method and the utilization of the _F1 by the rattan root, and is realized according to the following steps.

1. Breeding of perennial sterile lines and restorer lines. O. longistaminata and O. rufipogon are ideal perennial wild parents. Japonica rice G4362, P1839, etc. are high-yield, high-quality and perennial root donors. They were used to breed the perennial male sterile line GP8A and the perennial sterile male sterile line CP8A respectively, and the two types of male sterile lines could reproduce sexually and asexually. The perennial restorer lines G4362 and P1839 are directly measured from conventional japonica rice varieties, and can also be bred by crossing existing restorer lines and perennial root systems. The perennial restorer lines are propagated asexually and by seeds.

2. The perennial root F ₁ obtained by crossing the homozygous perennial male sterile line and the restorer line has been used for many years to reproduce heterosis.

3. Perennial root hybrid rice is cultivated in long-term no-till paddy fields or dry land. Beneficial organisms such as green manure, beneficial insects, and beneficial microorganisms form a natural balance with harmful organisms such as pests, weeds, and diseases in the growing area of perennial rice, and harmful organisms are not easy to cause disasters. Therefore, the perennial rice area basically does not apply pesticides to control pests and weeds. The main field operation of a rice farmer is harvesting rice ears. The residues are decomposed into fertilizers on the spot, and no nitrogen fertilizer or less nitrogen fertilizer can be applied in the active area of nitrogen fixation. Replace the Shinjuku root combination every four to five years.

The underground rhizomes of the perennial sterile line and its perennial F ₁ hybrids are automatically transplanted and rejuvenated, and the perennial roots do not decline for many years. The automatic transplantation of rhizomes adjusts the field density by itself. There is no need for artificial transplanting and rejuvenation and artificial adjustment to control the field density.

The completely non-photosensitive perennial CMS line and the perennial plants of the completely non-photosensitive perennial _F1 are heading and maturing continuously, harvested once a month, and harvested several times a year. Dormant until early winter.

The perennial sterile line, especially the sterile line produced by asexual reproduction of a single plant, can reach 100% high purity.

Example 2:

1. Recross breeding of ratoon male sterile lines and restorer lines

Guangjaponica A/Liuzhou wild rice//Changyao wild rice was planted with perennial roots and crossed F ₁ 4020. The rhizome homozygous 4020-821 and 4020-824-1 were selected from F ₂ and F ₃ . 886A, which has eliminated the wild traits, was obtained by self-crossing the F ₁ of the testcross of the GMS line cultivated rice and 4020F ₁ with the cultivated rice. 886A was crossed with 4020-821 and then selfed and siblings were crossed to isolate a homozygous neat strong rhizome cold-resistant drought-resistant non-shattering perennial root male sterile line that met the production requirements. The fertile plants in the GMS line were selected by selfing to obtain the wild-type rattle maintainer line. Then it was continuously backcrossed with the wild sterile line to breed the perennial wild sterile line.

The perennial restorer lines G4362 and P1839 were directly obtained from conventional japonica varieties. It can also be bred by crossing the current restorer line with the perennial root system. The perennial root restorer line implements vegetative propagation and seed propagation.

2. Reproduction of perennial male sterile lines and production of perennial hybrid rice seeds

The perennial root marks the GMS line for brother-sister crossing, self-breeding, and the male fertile plants in the brother-sister crossing or self-breeding group are completely eliminated and only the sterile plants are left for the perennial root propagation to expand the group. The perennial male sterile line adopts backcross reproduction and asexual reproduction to expand the population.

The ratoon CMS line is crossed with the ratoon restorer line or the annual restorer line. Because the rhizome and cold-resistant perennial are dominant, the F ₁ produced by the combination of the perennial male sterile line and the restorer line must be perennial. It's just that the perennial roots of the F ₁ combinations produced by the annual restorer line are different, so they can be used optimally.

The perennial CMS line and the perennial restorer line were alternately planted to produce perennial root F ₁ hybrid seeds. The automatic transplantation of sterile lines or restorer lines with rhizomes will make the parents interlaced and mixed together to grow. After mixed harvesting, the hybrid seeds can be selected by net sieving according to the difference in grain width of the parents. It can also be used for single plant or group selection in segregated _F1 populations and then for vegetative reproduction of perennial roots.

3. Production and Utilization of Perennial F ₁ Hybrid Rice

The field operation of ratoon hybrid rice is the same as that of current annual rice when seeding with grain to establish the original plant population. Prototype populations are completely insensitive to light, have an independent vegetative growth period after emergence, and then enter the reproductive growth period to begin to differentiate young ears. After harvesting for the first time, the perennial root strain produced by the rice pile no longer has special vegetative growth but emerges and differentiates the ears synchronously. After one month, the ears will be heading when 4-5 leaves, and the ears will be yellow and ripe in 30 days. It takes about 60 days from seedling emergence to panicle ripening. When the ears of the previous batch of perennial seedlings were yellow, the second batch of perennial seedlings booted and the third batch of root tillers emerged. This is the three synchronizations of panicle differentiation, heading, and panicle ripening of perennial rice, which are carried out continuously. In the tropics, there are always panicles that can be harvested throughout the year. In the subtropical zone, when the monthly average temperature is lower than 10°C, the rhizomes stop growing and go dormant until the temperature rises above 10°C and then germinate and regenerate new shoots. Although the temperature is high in summer, in case of drought, the rhizomes will stop growing and go dormant. When it rains after a drought, the rhizomes germinate rapidly and restore vitality. The ability to avoid cold and drought during dormancy is formed by the long-drug wild rice in the evolution of hundreds of millions of years, and now it is inherited to the hybrid rice with perennial roots. Therefore, the perennial root rice does not need artificial irrigation in winter, nor artificial cold protection. The perennial root hybrid rice of the present invention can endure the coldest monthly average temperature of 5°C, with an extreme value of -7.9°C.

Compared with the current intensive cultivation of annual rice, the perennial root hybrid rice is relatively extensive. Under relatively extensive conditions, the production can be increased by reproducing heterosis fixedly and harvesting multiple times per year.

Claims (1)

1, a kind of method of producing hybrid rice with the perennial root method, it is characterized in that with photostable long medicine wild rice O.longistaminata and the wild rice O.rufipogon in Liuzhou be the wild parent of perennial root, japonica rice G4362, P1839 are the perennial root donor, breed perennial root caryon sterile line GP8A and male sterile line CP8A is lost in the perennial root open country; Again perennial root caryon sterile line GP8A and perennial root open country are lost male sterile line CP8A for maternal, recovery are that japonica rice G4362, P1839 are male parent preparation perennial root crossbreed, produce the perennial root hybrid rice with the perennial root crossbreed.