CN102144534A - Method for breeding Medicago sativa L. male sterile line - Google Patents

Abstract

The invention discloses a method for breeding Medicago sativa L. male sterile line. The method is characterized by comprising the following steps of: performing interspecific distant hybridization on wild Medicago falcata L. from Xilin Gol grassland of Inner Mongolia which is used as female parents purple alfalfa from Jungar grassland of Inner Mongolia which is used as male parents; obtaining male sterile line Ms-4 from the offsprings; back crossing four male parents with the male sterile line Ms-4; performing cuttage propagation on the male sterile plants in each back cross offspring, and testing the combining ability of the agronomic traits for further selecting two excellent male sterile lines of the Medicago sativa L. with high combining ability and high volume of production from the male sterile plants, wherein the two excellent male sterile lines are named Ms-4-1 and Ms-4-2. The sterile lines obtained by the method have high combining ability, excellent fertility, high male infertility rate up to 100% and stable heredity.

Description

The selection of clover male sterile line

Technical field

The present invention relates to a kind of herbage breeding method, refer in particular to a kind of selection of clover male sterile line.

Background technology

Clover (Medicago sativa L.) is one of leguminous forage of extensively planting in the world, has kind more than 60 in the whole world, and China has 16 kinds.Because characteristics such as its nutritive value and forage yield obviously are better than other careless class, therefore be called as " king of herbage ".In addition, the clover well developed root system, nodule nitrogen fixation, the infertile field of improving the soil has good ecological functions.Along with the construction of Developing of Animal Industry, ecotope and the promotion of commodity economy, the clover cultivated area enlarges year by year in recent years, and its industrialized scale development is rapid, and national clover cultivated area reached 4,130,000 hm to 2008 ²(Lu Xin stone 2010), but still shortage of the clover new varieties that satisfy different production demands.Therefore, cultivate high yield, high-quality, efficient, many anti-, ecological and safe clover new varieties have become the target that domestic and international clover researchers constantly pursue.

Heterosis breeding is to improve alfalfa output, improves quality, strengthens the effective way of resistance.The seed selection of male sterile line is the important foundation of heterosis utilization.Utilize the crossbreed of male sterile line preparation, its output and resistance advantage are remarkable.Simultaneously, utilize male sterile line can save artificial emasculation, carry out the large tracts of land hybrid seeding.And that the utilization of clover male sterile line has is easier than crops, superior characteristic more.The one, clover is mainly gathered in the crops trophosomes such as cauline leaf, rather than seed, generally can not need to recover system.When not finding maintenance line, can utilize asexual reproduction method, with male sterile plants breeding with keep; The 2nd, the F1 of clover is for utilizing continuously for many years, and the hybrid seeding isolated area also can be utilized for many years continuously.Therefore, utilizing clover male sterile line preparing hybrid kind, is one of effective technology measure of heterosis breeding.

The clover male sterile line as far back as Canada by seed selection and utilization (Wu Yong applies 1984), many scholars of states such as the U.S., Russia, Hungary, Bulgaria, France, Japan also cultivate the clover male sterile line in succession later on, and utilize it to do a large amount of cross experiments, obtained good crossbreed.The report of relevant selection and patent issue is then rare.

Summary of the invention

The technical problem to be solved in the present invention provides a kind of selection of clover male sterile line, but uses the clover male sterile line that a kind of male sterility of this method seed selection is stable, coordinate force is strong, hybrid seed yield is high.

The technical problem to be solved in the present invention is realized by following steps:

Step 1, utilize the wild sickle alfalfa in grassland, Siklingelei, the Inner Mongol to carry out interspecific hybridization with the accurate Ge Er alfalfa in the Inner Mongol for male parent, breed No. 1 assorted russian fenugreek herb in grassland (Medicago varia Martin.cv.Caoyuan No.1) for maternal;

Step 2, on the grassland No. 1 assorted russian fenugreek herb flowering stage, the flower pesticide of each plant of field examination, every discovery flower pesticide is shrivelled, does not have the few plant of pollen or pollen, hangs up label, put on code name in order, therefrom select 6 strain male sterile plants, further to its pollen fertility carry out repetitive identified, therefrom select the complete and female No. 4 sterile strains of educating of male sterile, and adopt the branch cutting method to breed to it, obtain male sterile line Ms-4;

Step 3, choose 40 parts of alfalfa varieties (kind), male sterile line Ms-4 is carried out the test cross test, find that each male parent all can and can recover its fertility with male sterile line Ms-4 hybridization;

Step 4, for improving the bad reproduction proterties of male sterile line Ms-4, choosing 4 clover materials with different merits is male parent (No. 1 assorted russian fenugreek herb in grassland, No. 2 assorted russian fenugreek herbs in grassland (M.varia Martin.cv.Caoyuan No.2), sickle alfalfa (M.falcate L.), the crossbreed of male sterile line Ms-4 and Xinjiang big Leaf alfalfa (M.varia Martin.cv.CaoyuanNo.1 * M.sativa L.cv.Xinjiang Daye)) carries out artificial hybridization, through 1-3 backcross transformation, obtain 12 male sterile plants from offspring's separation, utilize branch cutting breeding and tissue culture technique, set up the stable clover male sterile line of proterties;

Step 5, to 12 male sterile lines that backcross transformation obtains, carry out Combing Ability of Main Agronomic Character and measure, therefrom filter out 2 of all high male sterile lines of coordinate force and hybrid seed yield, name and be Ms-4-1 and Ms-4-2;

The crossbreed of step 6, this male sterile line and the preparation of specific alfalfa variety, its F ₁For the forage yield competitive advantage greater than 40%.

The clover male sterile line of breeding with the present invention has following advantage:

1, former clover male sterile line Ms-4 and the low problem of the ubiquitous hybrid seed yield of external clover male sterile line have been overcome.Use the backcross transformation method, improved male sterile line gynoecium fertility, significantly improved ripening rate.Further measure, successfully select all high good male sterile line of hybrid seed yield and coordinate force by coordinate force and economical character.

2, the clover male sterile line that selects thus, its male sterility is thorough, and is not affected by environment, and sterile rate reaches 100%.This male sterile line can with specific alfalfa variety preparing hybrid kind, its forage yield advantage is remarkable, the probability that pseudostationary produces is minimum.

Among the present invention, male sterile line Ms-4 seed selection from clover distant hybrids (No. 1 assorted russian fenugreek herb in grassland) is come out, and the used male parent material of backcross transformation is the crossbreed F of No. 1 assorted russian fenugreek herb in grassland, No. 2 assorted russian fenugreek herbs in grassland, sickle alfalfa, male sterile line Ms-4 and Xinjiang big Leaf alfalfa ₁Generation.Therefore, all the sterile strains and the crossbreed that go out of assembly is the scope that the present invention protects.

Description of drawings

Fig. 1 is the flow chart of the selection of clover male sterile line

Embodiment

Below in conjunction with the embodiment of accompanying drawing for a selection: 1, on the grassland an assorted russian fenugreek herb (with the wild sickle alfalfa in grassland, Siklingelei, the Inner Mongol is female parent, accurate Ge Er alfalfa is that paternal hybrid forms) flowering stage, the flower pesticide of each plant of field examination, every discovery flower pesticide is shrivelled, do not have the few plant of pollen or pollen, hang up label, put on code name in order, therefrom select 6 strain male sterile plants, selected 1 strain male sterile plant in average 7-10 ten thousand strains.

2, the fertility of 6 sterile strain pollen is carried out repetitive identified, the field is hung up 3-4 inflorescence of each plant clip of label, take back indoorly, examine under a microscope and detect pollen fertility.Wherein fertile flower powder volume is bigger, for the 3-4 of sterile flower powder doubly, and have nuclear and dense cytoplasm to be full of whole pollen grain.And long-pending less, seedless, shrivelled, the ghost of pollen sterile plastochondria only has cytoplasm around pollen grain, and middle vacuole is bigger, and the fold texture on pollen grain surface is darker.Statistics does not have pollen grain (non-pollen type) fully, or pollen grain is arranged but all is the plant proportion of sterile flower powder (pollen abortion type).Identify discovery through the pollen grain fertility, 1,2, No. 3 is the part male sterile line, and the pollen sterility rate is 80.0%-90.2%; Male sterile line 4-6 number is the holandry male sterile line, and the pollen sterility rate is 100%, but is male sterile line No. 5 and No. 6, is again female sterile system, does not have using value in the crossbreed preparation.Therefore, therefrom select male sterile and female No. 4 sterile strains of educating, and adopt the branch cutting method to breed, obtain male sterile line Ms-4 it.

3, choose 40 parts of alfalfa varieties (kind), male sterile line Ms-4 is carried out test cross test, find that each male parent all can and can recover its fertility with male sterile line Ms-4 hybridization.Wherein the crossbreed F1 for preparing of male sterile line Ms-4 and Xinjiang big Leaf alfalfa is with the obvious advantage for forage yield, but hybrid seed yield is low.For this reason, the biology of reproduction of clover male sterile line Ms-4, female stamen cytomorphology, the anatomical research of floral nectary have further been carried out.Found that male sterile line Ms-4 inflorescence is short, every inflorescence Xiao Hua number is few, the column cap area is little, nectary secretion is few etc., and defective is the main cause that causes hybrid seed yield low.Abroad utilizing clover male sterile assembling cross-fertilize seed producing the not reason of extensive use by literature, mainly also is yielded poorly by the production of hybrid seeds to influence.

4, for improving the bad reproduction proterties of male sterile line Ms-4, choosing 4 clover materials with different merits is that male parent (being respectively the crossbreed of No. 1 assorted russian fenugreek herb in grassland, No. 2 assorted russian fenugreek herbs in grassland, sickle alfalfa, male sterile line Ms-4 and Xinjiang big Leaf alfalfa) is carried out artificial hybridization.Through backcross transformation repeatedly, separate to obtain 12 male sterile plants from the offspring.Utilize branch cutting breeding and tissue culture technique, set up the stable clover male sterile line of proterties.

5,12 male sterile lines that backcross transformation is obtained are carried out Combing Ability of Main Agronomic Character and are measured, and therefrom filter out 2 of all high male sterile lines of coordinate force and hybrid seed yield, name to be Ms-4-1 and Ms-4-2.

Claims (1)

1. the selection of clover male sterile line is characterized in that comprising the steps:

Step 1, utilize the wild sickle alfalfa in grassland, Siklingelei, the Inner Mongol to carry out interspecific hybridization with the accurate Ge Er alfalfa in the Inner Mongol for male parent, breed No. 1 assorted russian fenugreek herb in grassland for maternal;

Step 2, on the grassland No. 1 assorted russian fenugreek herb flowering stage, the flower pesticide of each plant of field examination, every discovery flower pesticide is shrivelled, does not have the few plant of pollen or pollen, hangs up label, put on code name in order, therefrom select 6 strain male sterile plants, further to its pollen fertility carry out repetitive identified, therefrom select the complete and female No. 4 sterile strains of educating of male sterile, and adopt the branch cutting method to breed to it, obtain male sterile line Ms-4;

Step 3, choose 40 parts of alfalfa varieties or kind, male sterile line Ms-4 is carried out the test cross test, find that each male parent all can and can recover its fertility with male sterile line Ms-4 hybridization;

Step 4, for improving the bad reproduction proterties of male sterile line Ms-4, choosing 4 clover materials with different merits is male parent, carry out artificial hybridization, the male parent material is respectively the crossbreed of No. 1 assorted russian fenugreek herb in grassland, No. 2 assorted russian fenugreek herbs in grassland, sickle alfalfa, male sterile line Ms-4 and Xinjiang big Leaf alfalfa, through 1-3 backcross transformation, obtain 12 male sterile plants from offspring's separation, utilize branch cutting breeding and tissue culture technique, set up the stable clover male sterile line of proterties;

Step 5, to 12 male sterile lines that backcross transformation obtains, carry out Combing Ability of Main Agronomic Character and measure, therefrom filter out 2 of all high male sterile lines of coordinate force and hybrid seed yield, name and be Ms-4-1 and Ms-4-2;

The crossbreed of step 6, this male sterile line and the preparation of specific alfalfa variety, its F ₁For the forage yield competitive advantage greater than 40%.

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