CN107360966A - Breeding method and propagation method of an indica-japonica intermediate CMS line Chunjiang 35A with early flowering time and high stigma exposure rate - Google Patents

Abstract

The invention discloses a breeding method and a propagation technology of indica-japonica intermediate sterile line Chunjiang 35A with early flowering and high stigma exposure rate, belonging to the field of rice heterosis utilization. The breeding method of the invention comprises the following steps: selecting indica late japonica rice maintainer line Chunjiang 19B with high stigma exsertion rate, early flowering time, stripe disease resistance and other characteristics and a partial indica type maintainer line Chunjiang 23B with high stigma exsertion rate, extremely early flowering time and other characteristics for hybridization, then carrying out backcross by taking late japonica rice sterile line Chunjiang 16A with high stigma exsertion rate, extremely early flowering time and other characteristics as male parents, and planting backcross progeny to B₆F₁The generation number is low and stable, and the name is Chunjiang 35A. The indica-japonica intermediate sterile line bred by the method has the advantages of early flowering time, high stigma exposure rate, high outcrossing seed setting rate, strong stress resistance (concrete) and excellent quality。

Description

Selection of an indica-japonica intermediate CMS line Chunjiang 35A with early flowering time and high stigma exposure rate methods of breeding and reproduction

technical field

The invention relates to a breeding method of Dian I-type indica-japonica intermediate male sterile line, in particular to a breeding and propagation method of an indica-japonica intermediate male sterile line Chunjiang 35A with early flowering time and high stigma exposed rate.

Background technique

In recent years, in japonica rice areas and indica-japonica mixed planting areas in Jiangsu, Anhui, Zhejiang, Shanghai and other provinces and cities, the occurrence of stripe leaf blight of japonica rice varieties has increased year by year. Therefore, the breeding of new hybrid japonica rice combinations must pay attention to stripe leaf blight. In order to solve the resistance problem of stripe blight, the transfer of japonica rice sterile lines resistant to stripe blight has become one of the keys to the resistance breeding of hybrid japonica rice stripe blight.

In addition to the excellent comprehensive traits of the new hybrid japonica rice combination, the yield of seed production is also an important factor affecting whether it can be popularized in a large area. Most of the three-line japonica sterile lines currently used in production in my country generally have no or low exposure rate of stigma, late flowering time, low outcross seed setting rate and low seed production, which restricts hybrid japonica rice to a certain extent. The popularization and application of new combinations urgently require the breeding of japonica male sterile lines with high outcrossing seed setting rate in order to increase the yield of seed production.

In addition, the current japonica CMS lines in Zhejiang Province are mainly of late japonica type, such as Ning 67A, Yongjing 2A, Chunjiang 12A, Xiushui 110A and other CMS lines, all of which are late japonica CMS lines. Due to the limitation of the strong photosensitivity of the sterile line, the photosensitivity of the hybrid japonica rice or the combination of indica and japonica subspecies hybrid rice is also strong, and some combinations even have a long growth period and cannot be used in Zhejiang Province. Therefore, in order to breed hybrid japonica rice or indica-japonica interspecies hybrid rice combinations with a shorter full growth period, it is first necessary to enrich the maturity stage types of japonica rice CMS lines, such as breeding japonica rice sterile lines with weak light sensitivity and temperature sensitivity. line, it has greater flexibility and initiative when considering the growth period in the allocation of hybrid rice combinations.

Therefore, cultivating medium japonica male sterile lines with early flowering, high stigma exposure rate and strong stress resistance is of great significance for improving seed production and popularizing new combinations of hybrid japonica rice.

Contents of the invention

The object of the present invention is to provide a breeding and propagation method of Chunjiang 35A, a medium-japonica male sterile line with early flowering time, high stigma exposed rate and strong stress resistance, so as to breed early flowering time, high stigma exposed rate and strong stress resistance The medium japonica male sterile line is used to increase the yield of hybrid rice combination seed production and to be popularized and applied in production.

In order to achieve the above object, the present invention adopts the following technical solutions:

A method for breeding an indica-japonica intermediate CMS line Chunjiang 35A with early flowering time and high stigma exposed rate, the method comprises the following steps:

1) Select the maintainer line Chunjiang 19B of the indica type japonica rice with the characteristics of high stigma exposure rate, early flowering time and resistance to stripe leaf blight, and the temperature-sensitive medium japonica maintainer line Chunjiang 23B with the characteristics of high stigma exposure rate and early flowering time Hybridization, hybridization to obtain F ₁ seeds;

₂ ) After _{subgeneration} of F1, screen the agronomic traits, stigma exposure rate and flowering time of each individual plant of the F2 population, and select individual plants with good agronomic traits, good stress resistance, high stigma exposure rate, and early flowering time; Plant F ₃ strains, screen for agronomic traits, stress resistance, stigma exposure rate and flowering time, and select excellent single plant B36;

3) The japonica CMS line Chunjiang 16A with high stigma exposed rate and very early flowering characteristics was used for test crossing of B36; the test cross F _{1 was planted, and the test cross F 1 with} the ability to maintain sterility was returned to the male parent B36 At the same time, combined with the determination of combining ability and fertility identification, B ₆ F ₁ was obtained through two generations a year. The backcross lines were neat and consistent in the population, the bagging self-seed setting rate was zero, and the agronomic traits and fertility were stable. Consistent, a medium-japonica CMS line Chunjiang 35A with compact plant type, short stalks and dense panicles, early flowering time, good outcrossing rate, high seed production yield and strong stress resistance was bred, and its backcross male parent was B36;

4) Use Chunjiang 35A as the female parent and Chunjiang 35B as the male parent to propagate the seeds of Chunjiang 35A.

The present invention is a breeding method of Chunjiang 35A, an indica-japonica intermediate CMS line with early flowering time and high stigma exposed rate. The method comprises the following steps: using Chunjiang 35A as the female parent and B36 as the male parent. Simultaneous sowing, when sowing, the seed amount of Chunjiang 35A is 0.8-1.0 kg/mu, B36 is 0.2-0.25 kg/mu, the seedling age is controlled at 20-30 days, the row ratio of father and mother is 2:8, and the row spacing of female parent is 16.7 cm × 20.0 cm, single or double planting; 1-2 days before the breach period, cut off half of the sword leaves of the father and mother at the same time, and spray "920" twice at the initial breach stage 6 -8 grams, spray 4-6 grams/mu for both parents when 5% of the plants are heading for the first time, spray the second time at 1-2 days interval, 2 grams/mu, and cut off the maintenance line in time after the powder is finished. .

Chunjiang 35A of the present invention has the following beneficial effects:

1) Excellent quality: According to the analysis of the Rice and Product Quality Supervision, Inspection and Testing Center of the Ministry of Agriculture, according to the NY/T593-2013 "Edible Rice Variety Quality" standard, among the 12 indicators of the spring river 35B test of the maintainer line Chunjiang 35A, the whole The polished rice rate, transparency and amylose content reach the first-class standard, the brown rice rate and chalkiness reach the second-class standard, and the grain length is 6.2mm, which is longer than the general japonica rice grain type;

2) Strong stress resistance;

3) High outcrossing rate: Chunjiang 35A blooms early, with a stigma exposure rate of over 50%, good outcrossing and firmness, easy seed production and propagation, and high yield. In spring 2014, spring 2015 and spring 2016, the hybrid combination of Chunjiang 35A was produced in Hainan, and the seed setting rate was above 75%. If we further study the supporting high-yield technology of seed production, it is expected to obtain higher seed production yield in a larger area.

Description of drawings

Figure 1 is a schematic diagram of the breeding pedigree of the present invention.

detailed description

Below in conjunction with accompanying drawing (Fig. 1) further illustrate breeding method of the present invention.

Breeding method of CMS line Chunjiang 35A:

A) Select the maintainer line Chunjiang 19B, which has the characteristics of high exposed stigma rate, early flowering time, and resistance to stripe leaf blight, and the temperature-sensitive medium-japonica maintainer line, which has the characteristics of high exposed stigma rate and early flowering time. Chunjiang 23B, hybridized to obtain F ₁ seeds;

B ₎ After adding F1, screen the agronomic traits, stigma exposure rate and flowering time _of each individual plant in the F2 population, and select individual plants with good agronomic traits, good stress resistance, high stigma exposure rate, and early flowering time. F ₃ strains were planted, screened for agronomic traits, stress resistance, stigma exposure rate and flowering time, and selected excellent individual plants.

C) The selected excellent individual plants will continue to be backcrossed with the late japonica rice CMS line Chunjiang 16A, which has the characteristics of high stigma exposure rate and extremely early flowering time, as the male parent, and at the same time start combining combining ability determination and fertility identification. The second generation of B ₆ F ₁ was obtained by transfection. The backcross lines were neat and consistent in the population, and the bagging self-seed setting rate was zero. The agronomic traits and fertility were stable and consistent. Chunjiang 35A is a medium japonica male sterile line with early, good outcrossing rate, high seed production yield and strong stress resistance.

Breeding method of CMS line Chunjiang 35A:

1. Select ideal breeding fields and suitable seasons

CMS breeding fields should be selected far away from other rice fields, with good natural isolation, low wind, sunny, convenient irrigation and drainage, good soil quality, and the best non-rice fields for previous crops. In terms of seasons, it is best to stagger the flowering period with other rice to prevent pollination.

2. Determine the sowing date

For single-late breeding of Spring River 35A in Hangzhou area, it is advisable to sow Spring River 35A and B36 at the same time in mid-to-early June. Under normal circumstances, it heads in mid-September.

3. Cultivate strong seedlings with tillers

The seed rate of Chunjiang 35A is 0.8-1.0 kg/mu, that of Chunjiang 35B is 0.2-0.25 kg/mu, and the seeding rate of seedling fields is controlled at 7.0-8.0 kg/mu. Seedling age is controlled at about 25 days.

4. Determine a reasonable planting ratio

The reasonable planting ratio of the parents is to increase the planting ratio of the female parent to the greatest extent, increase the number of effective spikelets of the female parent, and ensure sufficient pollen to increase the outcross seed setting rate. According to many years of experiments, the ideal ratio of father and mother is 2:8 when transplanting, and the male parent is planted with a row spacing of 16.7 cm × 20.0 cm, and single or double plants are inserted. The row spacing of the female parent plant is 16.7 cm × 20.0 cm, 2 plants are inserted in each cluster, and the parent plant spacing is 24 cm. Put the field in time to promote rooting, apply flower-preserving fertilizers, apply 5 kg of urea per mu, and 5 kg of potassium chloride, so that the group is coordinated, the individual is strong, the large spikes are cultivated, and the number of effective florets is increased. Combined with fertilization, timely observe the parental parent's young panicle differentiation process. If there is a difference, apply more nitrogen fertilizer to the faster growing side, and apply more potassium fertilizer to the slower growing side, so that the parental parent is in the best flowering state.

5. Artificially assisted pollination to improve seed setting rate

1-2 days before the breach period, the father and mother cut off 1/2 of the flag leaves at the same time, so that the pollen of the father is easy to scatter, and the pollination rate of the mother is improved. At the beginning of the breach, spray "920" 6-8 g/mu twice, the first time when 5% of the plants are heading, both parents are sprayed, 4-6 g/mu, spray the second time every other day, 2 g/mu, Make the earing of the father and mother parents concentrated and orderly, elongate the neck of the ear, concentrate the flowers for pollination, cooperate with artificial pollination, improve the outcrossing seed setting rate, and obtain higher seed reproduction yield.

6. Field pest control

The control of diseases and insect pests such as rice blast, sheath blight, brown planthopper, leaf roller, large borer, and rice stem borer is the same as that of general japonica rice varieties. The key to the prevention and control of rice stripe disease is to timely plow and eliminate weeds in seedling fields before overwintering, avoid wheat fields as much as possible, strengthen the control of rice brown planthopper in seedling field stage, and cut off the way of virus transmission.

7. Impurity removal standards and technical points

The parental seeds of the original species are used for propagation, and the natural space is isolated within 500 meters, and there are no rice varieties. Strictly remove impurities to ensure the quality of seeds, and strictly remove impurities during the entire growth period, especially before and after earing. The first 1-2 days before the first spraying of "920" is the critical period for removing impurities. The maintainer lines and other non-sterile plants mixed into the female parent should be removed as soon as possible. Guarantee the seed quality of the sterile line. Strictly prevent mechanical mixing in all aspects of harvesting, drying, storage and transportation to ensure the purity of seeds.

Claims (2)

1. Xian round-grained rice osculant sterile line spring river 35A early when a kind of colored, stigma exposing ratio is high selection, it is characterised in that This method comprises the following steps：

1) selection with stigma exposing ratio height, Hua Shizao, anti-stripe virus disease characteristic mix indica type japonica rice maintainer spring river 19B and With stigma exposing ratio is high, round-grained rice maintainer spring river 23B hybridizes in temperature sensitive type of Hua Shite morning characteristics, hybridization obtains F₁Seed；

2) by F₁After adding generation, to F₂Screened when the economical character of each individual plant of colony, stigma exposing ratio and flower, be selected in agronomy Shape is good, good stress resistance, stigma exposing ratio are high, Hua Shizao individual plant；Plant F₃Strain, carry out economical character, resistance, outside column cap Screening when dew rate and flower, is selected in fine individual plant B36；

3) B36 carries out test cross with the japonica rice sterile spring river 16A with stigma exposing ratio height, Hua Shite morning characteristics；Plant test cross F₁, and to the test cross F with sterile holding capacity₁It is returned with male parent B36；Start simultaneously at and reflected with reference to combining ability test, fertility Fixed, in 1 year two generation, carried out transformation and obtains B₆F₁, neat and consistent in strain colony is returned, bagging self-fruitful rate is zero, economical character It is consistent with stable fertility, cultivate compact plant type, dense cluster of short stem, Hua Shizao, outcrossing rate is good, hybrid seed yield is high, strong stress resistance Middle round-grained rice sterile line spring river 35A, it is B36 that it, which is returned male parent,；

4) it is maternal with spring river 35A, is male parent with spring river 35B, breeds spring river 35A seed.

2. Xian round-grained rice osculant sterile line spring river 35A early when a kind of colored, stigma exposing ratio is high propagation method, it is characterised in that This method comprises the following steps：Make female parent with spring river 35A, make male parent with B36, when the early and middle ten dayses same period in June sowing, sowing 0.8-1.0 kgs/acre of spring river 35A sowing quantity, B36 are 0.2-0.25 kgs/acre, and length of time rice seedlings grow control was at 20~30 days, father, maternal row Than 2:8, maternal 20.0 centimetres of 16.7 cm x of seeding row spacing, it is single this or double originally plant；1-2 days before the cut phase, father, female parent are cut simultaneously The sword-like leave of half is removed, and 6-8 grams of " 920 " are sprayed in two times initial stage in cut, first is inferior to Parent when 5% plant ears 4-6 grams/acre is all sprayed, interval sprays second for 1-2 days, 2 grams/acre, catches up with powder to prescind maintainer in time after terminating.