Distant hybridization breeding method for arundo donax and corn hybrid wheat

Abstract

The invention relates to the technical field of crop breeding. The invention provides a distant hybridization breeding method for bamboo reed and corn hybrid wheat, which comprises the following steps: by taking bamboo reed as a stock and corn hybrid wheat as a scion, realizing distant asexual hybridization breeding in a grafting manner, and then artificially pollinating and breeding to obtain sexual bamboo reed and corn hybrid wheat. According to the technical scheme, the characteristics of high yield of distant plant corn, rhizome of arundo donax, natural disaster resistance and the like are transferred to wheat, a new variety with strong heterosis is obtained, the breeding period is shortened, the production performance of the wheat is obviously improved, and the yield of the wheat is increased.

Description

Technical Field

[0001] The invention relates to the technical field of crop breeding, and in particular to a distant hybridization breeding method of Phragmites australis and corn hybrid wheat. Background Art

[0002] As a perennial herb, Phragmites australis has rich nutritional value and a wide range of practical uses. Its rhizomes are rich in protein, vitamins and minerals, and are a high-quality feed raw material. Phragmites australis rhizomes are highly adaptable, prefer warm and humid environments, have good cold resistance, and can grow in slightly acidic or slightly alkaline soils. Phragmites australis grows quickly, with tall and upright plants, thick stems and wide leaves. This allows Phragmites australis to form dense vegetation in a short period of time, which has a high ecological value. Phragmites australis has strong adaptability to the environment, can grow in a variety of soil and climatic conditions, and has strong resistance to stress.

[0003] Wheat is an annual or biennial herbaceous plant of the Gramineae family and the Triticeae genus. It is a nutritious and economically valuable commodity grain and one of the three major grain crops in my country. People have a very high demand for wheat. However, due to the differences in environmental characteristics in different regions and changes in environmental climate in recent years, the growing environment of wheat faces many challenges, which has a significant impact on the yield and quality of wheat.

[0004] Based on the above, it is very necessary to obtain new wheat varieties with excellent characteristics, which can meet the planting requirements of different environmental conditions and significantly increase yields through some breeding methods. Summary of the invention

[0005] The purpose of the present invention is to provide a distant hybridization breeding method of Phragmites australis and corn hybrid wheat, which transfers the high yield of the distant plant corn, the rhizome and natural disaster resistance of Phragmites australis to wheat, and obtains a new variety with strong hybrid advantages, which not only shortens the breeding period, but also significantly improves the production performance of wheat and increases its yield.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a distant hybridization breeding method of Phragmites australis and corn hybrid wheat, comprising the following steps:

[0008] (1) soaking the selected corn hybrid wheat seeds and then performing a germination treatment;

[0009] (2) when the embryo of the corn hybrid wheat grows to 2-3 cm, the embryo is cut off at an angle of 40-50 degrees upward, and an incision is made on the top of the young shoot of Phragmites australis, and then the young shoot of Phragmites australis is attached to the cut incision of the corn hybrid wheat embryo to obtain a grafted seedling;

[0010] (3) pre-cultivating the grafted seedlings for 2-3 days and then transferring them to a culture medium, and transplanting them after the leaves become straight and the seeds are formed, thereby cultivating asexual Phragmites australis-corn hybrid wheat;

[0011] (4) The asexual Phragmites-corn hybrid wheat was artificially pollinated to obtain the sexual Phragmites-corn hybrid wheat.

[0012] Preferably, the corn hybrid wheat is a sexual corn hybrid wheat obtained by artificial pollination of asexual hybrid wheat obtained by grafting corn as rootstock and wheat as scion, and the corn is a high-yield, disease-resistant glutinous corn.

[0013] Preferably, the soaking time in step (1) is 20-22 hours.

[0014] Preferably, the temperature of the germination treatment in step (1) is 26-28° C. Preferably, the step (1) includes disinfection treatment before soaking, and the disinfection treatment is soaking in a carbendazim solution, and the soaking time is 5-7 minutes.

[0015] Preferably, the carbendazim solution is prepared by mixing water and carbendazim wettable powder in a mass ratio of (14-16) kg:(45-55) g.

[0016] Preferably, the humidity of the pre-culture in step (3) is 80-85%.

[0017] By adopting the above technical solution, the present invention has the following beneficial effects:

[0018] In the technical solution of the present invention, the high yield of corn, the rhizome and natural disaster resistance of Phragmites australis are transferred to wheat to obtain a new variety of Phragmites australis-corn hybrid wheat with hybrid vigor, which not only shortens the breeding period, but also significantly improves the production performance of wheat and greatly increases the yield. The grafting operation of the present invention is carried out during the period of strongest plasticity, which also provides a basis for genes to cross the barriers of different species and increases the probability of successful grafting. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 For the germ of corn hybrid wheat ( Figure 1 The upper part of the is the germ);

[0020] Figure 2 Section of Phyllostachys australis buds ( Figure 2 1 represents the cortex of young shoots of Arundo donax, 2 represents the epidermis of young shoots of Arundo donax, 3 represents the vascular bundle of young shoots of Arundo donax, 4 represents the xylem of young shoots of Arundo donax, 5 represents the medullary cavity of young shoots of Arundo donax, and 6 represents the pith of young shoots of Arundo donax);

[0021] Figure 3 For grafted seedlings;

[0022] Figure 4It is the strong true leaves of the hybrid wheat of Phragmites australis and corn;

[0023] Figure 5 This is a picture of the root system of Phragmites-corn-wheat hybrid;

[0024] Figure 6 The three-leaf and four-leaf seedlings of Phragmites-corn-wheat hybrids;

[0025] Figure 7 It is the tillering stage of Phragmites australis-corn hybrid wheat;

[0026] Figure 8 The growth of wheat ears of Phragmites-corn hybrid wheat and corn hybrid wheat ( Figure 8 A in the figure represents a hybrid wheat of Phragmites australis and corn, B represents a hybrid wheat of corn, and C represents an ear of a hybrid wheat of Phragmites australis and corn);

[0027] Fig. 9 This is an oblique section of the Phragmites-Corn hybrid wheat stalk and the Phragmites stalk ( Fig. 9 A in the figure is an oblique section of a Phragmites australis-corn hybrid wheat stalk, wherein 7 represents the epidermis of the Phragmites australis-corn hybrid wheat stalk, 8 represents the sieve tube of the Phragmites australis-corn hybrid wheat stalk, 9 represents the cortex of the Phragmites australis-corn hybrid wheat stalk, 10 represents the basic tissue of the Phragmites australis-corn hybrid wheat stalk, 11 represents the vascular bundle of the Phragmites australis-corn hybrid wheat stalk, 12 represents the xylem of the Phragmites australis-corn hybrid wheat stalk, 13 represents the medullary cavity of the Phragmites australis-corn hybrid wheat stalk, and 14 represents the air cavity of the Phragmites australis-corn hybrid wheat stalk; B is an oblique section of a Phragmites australis stalk, wherein 15 represents the epidermis of the Phragmites australis stalk, 16 represents the sieve tube of the Phragmites australis stalk, 17 represents the cortex of the Phragmites australis stalk, 18 represents the phloem of the Phragmites australis stalk, 19 represents the xylem of the Phragmites australis stalk, 20 represents the cambium of the Phragmites australis stalk, 21 represents the vascular bundle of the Phragmites australis stalk, and 22 represents the air cavity of the Phragmites australis stalk);

[0028] Fig.10 The root system of Phragmites australis-corn hybrid wheat and Phragmites australis root system ( Fig.10 A is the root system diagram of Phragmites australis, B is the overall diagram of Phragmites australis-corn-wheat hybrid, and C is the root system diagram of Phragmites australis-corn-wheat hybrid). DETAILED DESCRIPTION

[0029] The present invention provides a distant hybridization breeding method of Phragmites australis and corn hybrid wheat, comprising the following steps:

[0030] (1) soaking the selected corn hybrid wheat seeds and then performing a germination treatment;

[0031] (2) when the embryo of the corn hybrid wheat grows to 2-3 cm, the embryo is cut off at an angle of 40-50 degrees upward, and an incision is made on the top of the young shoot of Phragmites australis, and then the young shoot of Phragmites australis is attached to the cut incision of the corn hybrid wheat embryo to obtain a grafted seedling;

[0032] (3) pre-cultivating the grafted seedlings for 2-3 days and then transferring them to a culture medium, and transplanting them after the leaves become straight and the seeds are formed, thereby cultivating asexual Phragmites australis-corn hybrid wheat;

[0033] (4) The asexual Phragmites-corn hybrid wheat was artificially pollinated to obtain the sexual Phragmites-corn hybrid wheat.

[0034] In the present invention, Phragmites australis and corn-wheat hybrid are selected as parent materials, wherein Phragmites australis is used as rootstock and corn-wheat hybrid is used as scion.

[0035] In the present invention, the corn hybrid wheat is a sexual corn hybrid wheat obtained by artificial pollination of asexual hybrid wheat obtained by grafting corn as a rootstock and wheat as a scion. The breeding method of sexual corn hybrid wheat in the present invention preferably includes the following steps: (a) Oblique needle grafting is performed with corn as a rootstock and wheat as a scion to obtain a grafted seedling; (b) The grafted seedling is planted and cultivated to obtain asexual corn hybrid wheat; (c) Corn pollen spores are artificially pollinated to asexual corn hybrid wheat ears pistils to obtain sexual corn hybrid wheat; (d) Corn pollen spores are artificially pollinated to sexual corn hybrid wheat ears pistils, and the operation is repeated for 3-4 rounds to obtain sexual corn hybrid wheat with stable expression. In the present invention, the corn hybrid wheat used in the steps (c) and (d) preferably needs to remove the stamens.

[0036] In the present invention, the corn is preferably high-yield, disease-resistant glutinous corn. The corn hybrid wheat cultivated by the present invention is a five-leaf, one-core variety. In the present invention, the corn hybrid wheat seeds that can be stably inherited are screened for disinfection, and the disinfection is preferably soaked in a carbendazim solution. The carbendazim solution of the present invention is prepared by water and carbendazim wettable powder, and the mass ratio of the water to the carbendazim wettable powder is preferably (14-16) kg: (45-55) g, further preferably (14.5-15.5) kg: (48-52) g, and further preferably 15 kg: 50 g. The soaking time of the present invention is preferably 5-7 min, and further preferably 6 min.

[0037] In the present invention, the sterilized corn hybrid wheat seeds are placed in water for soaking, and the soaking time is preferably 20-22 hours, and more preferably 21 hours.

[0038] In the present invention, the soaked corn hybrid wheat seeds are subjected to germination treatment after swelling and whitening, and the germination treatment temperature is preferably 26-28°C, and more preferably 27°C.

[0039] In the present invention, the embryos of corn hybrid wheat are germinated and cultured to a length of 2-3 cm before preparation for grafting. Figure 1) is cut obliquely upward, and the oblique angle is preferably 40-50 degrees, and further preferably 45 degrees. Then cut an incision (such as Figure 2 ), use a silver needle to fit the young shoots of Phragmites australis with the cut ends of the corn hybrid wheat germs to obtain a grafted seedling. In the present invention, preferably, a silver needle is used to pierce the center of the fit cut ends of the young shoots of Phragmites australis and the cut ends of the corn hybrid wheat germs, so that the two are penetrated and fixed together, and the joint (such as Figure 3 ).

[0040] In the present invention, the fixed grafted seedlings are pre-cultured, the pre-culture time is preferably 2-3 days, more preferably 3 days; the pre-culture humidity is preferably 80-85%, more preferably 81-84%, and more preferably 83%. The purpose of the pre-culture of the present invention is to make the callus tissue of the scion and the stock basically combine and start the scion.

[0041] In the present invention, the grafted seedlings after pre-cultivation are transferred to the culture medium for seedling raising, and are transplanted after the leaves are straight and the seeds are formed, so as to obtain asexual Phragmites australis-corn hybrid wheat. In the present invention, transplanting is preferably performed in the evening or on a cloudy day, and the soil is kept moist.

[0042] In the present invention, corn pollen is artificially pollinated into asexual Phragmites-Maize hybrid wheat ears pistil to obtain sexual Phragmites-Maize hybrid wheat, and then corn pollen is artificially pollinated into sexual Phragmites-Maize hybrid wheat ears pistil, and this operation is repeated for 3-4 rounds to obtain stably expressed sexual Phragmites-Maize hybrid wheat.

[0043] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0044] Example 1

[0045] A method for distant hybridization breeding of Phragmites australis and corn hybrid wheat, comprising the following steps:

[0046] (1) selecting Phragmites australis and corn hybrid wheat as parent materials, wherein Phragmites australis is used as a rootstock and sexual corn hybrid wheat is used as a scion, and the breeding steps of the sexual corn hybrid wheat are as follows: (a) using corn as a rootstock and wheat as a scion to perform oblique needle grafting to obtain a grafted seedling; (b) planting and cultivating the grafted seedling to obtain asexual corn hybrid wheat; (c) artificially pollinating corn pollen spores to asexual corn hybrid wheat ears pistils to obtain sexual corn hybrid wheat; (d) artificially pollinating corn pollen spores to sexual corn hybrid wheat ears pistils, repeating this operation for 3 rounds, and obtaining stably expressed sexual corn hybrid wheat;

[0047] (2) Stably inherited corn hybrid wheat seeds were soaked and disinfected in a carbendazim solution prepared by water and carbendazim wettable powder in a mass ratio of 15kg:50g, and then taken out and dried after soaking for 6 minutes, and then soaked in water for 21 hours. After the soaked corn hybrid wheat seeds were swollen and white, they were germinated at 27°C;

[0048] (3) After the embryo of the corn hybrid wheat is germinated and cultured to a length of 2 cm, the embryo of the corn hybrid wheat is cut off at an angle of 45 degrees upward, an incision is made on the top of the young shoot of Phragmites australis, and the young shoot of Phragmites australis is fitted with the incision of the embryo of the corn hybrid wheat using a silver needle, and the silver needle is inserted through the center of the fitted incision so that the two are penetrated and fixed together, and the joint is inserted into the joint to obtain a grafted seedling;

[0049] (4) Place the fixed grafted seedlings gently in a container covered with moist filter paper and pre-cultivate for 3 days at a humidity of 83%;

[0050] (5) transferring the pre-cultivated grafted seedlings to a culture medium for seedling raising, and transplanting them after the leaves become straight and the seeds are formed, thereby cultivating asexual Phragmites australis-corn hybrid wheat;

[0051] (6) Artificially pollinating corn pollen into asexual reed-corn hybrid wheat ears pistils to obtain sexual reed-corn hybrid wheat, and then artificially pollinating corn pollen into sexual reed-corn hybrid wheat ears pistils, repeating this operation for 3 rounds, and obtaining stably expressed sexual reed-corn hybrid wheat.

[0052] Example 2

[0053] A method for distant hybridization breeding of Phragmites australis and corn hybrid wheat, comprising the following steps:

[0054] (1) selecting Phragmites australis and corn hybrid wheat as parent materials, wherein Phragmites australis is used as a rootstock and sexual corn hybrid wheat is used as a scion, and the breeding steps of the sexual corn hybrid wheat are as follows: (a) using corn as a rootstock and wheat as a scion to perform oblique needle grafting to obtain a grafted seedling; (b) planting and cultivating the grafted seedling to obtain asexual corn hybrid wheat; (c) artificially pollinating corn pollen spores to asexual corn hybrid wheat ears pistils to obtain sexual corn hybrid wheat; (d) artificially pollinating corn pollen spores to sexual corn hybrid wheat ears pistils, repeating this operation for 4 rounds, and obtaining stably expressed sexual corn hybrid wheat;

[0055] (2) Stably inherited corn hybrid wheat seeds were soaked and disinfected in a carbendazim solution prepared by water and carbendazim wettable powder in a mass ratio of 14kg:50g, and then taken out and dried after soaking for 6 minutes, and then soaked in water for 20 hours. After the soaked corn hybrid wheat seeds were swollen and white, they were germinated at 26°C;

[0056] (3) After the embryo of the corn hybrid wheat is germinated and cultured to a length of 3 cm, the embryo of the corn hybrid wheat is cut off at an angle of 45 degrees upward, an incision is made on the top of the young shoot of Phragmites australis, and the young shoot of Phragmites australis is fitted with the incision of the embryo of the corn hybrid wheat using a silver needle, and the silver needle is inserted through the center of the fitted incision so that the two are penetrated and fixed together, and the joint is inserted into the joint to obtain a grafted seedling;

[0057] (4) Place the fixed grafted seedlings gently in a container covered with moist filter paper and pre-cultivate for 3 days at a humidity of 84%;

[0058] (5) transferring the pre-cultivated grafted seedlings to a culture medium for seedling raising, and transplanting them after the leaves become straight and the seeds are formed, thereby cultivating asexual Phragmites australis-corn hybrid wheat;

[0059] (6) Artificially pollinating corn pollen into the pistil of asexual Phragmites-Maize hybrid wheat ears to obtain sexual Phragmites-Maize hybrid wheat, and then artificially pollinating corn pollen into the pistil of sexual Phragmites-Maize hybrid wheat ears again, repeating this operation for 3 rounds, and obtaining stably expressed sexual Phragmites-Maize hybrid wheat.

[0060] Example 3

[0061] A method for distant hybridization breeding of Phragmites australis and corn hybrid wheat, comprising the following steps:

[0062] (1) selecting Phragmites australis and corn hybrid wheat as parent materials, wherein Phragmites australis is used as a rootstock and sexual corn hybrid wheat is used as a scion, and the breeding steps of the sexual corn hybrid wheat are as follows: (a) using corn as a rootstock and wheat as a scion to perform oblique needle grafting to obtain a grafted seedling; (b) planting and cultivating the grafted seedling to obtain asexual corn hybrid wheat; (c) artificially pollinating corn pollen spores to asexual corn hybrid wheat ears pistils to obtain sexual corn hybrid wheat; (d) artificially pollinating corn pollen spores to sexual corn hybrid wheat ears pistils, repeating this operation for 3 rounds, and obtaining stably expressed sexual corn hybrid wheat;

[0063] (2) Stably inherited corn hybrid wheat seeds were soaked and disinfected in a carbendazim solution prepared by water and carbendazim wettable powder in a mass ratio of 16kg:55g, and then taken out and dried after soaking for 6 minutes, and then soaked in water for 22 hours. After the soaked corn hybrid wheat seeds swelled and turned white, they were germinated at 28°C;

[0064] (3) After the embryo of the corn hybrid wheat is germinated and cultured to a length of 3 cm, the embryo of the corn hybrid wheat is cut off at an angle of 40 degrees upward, an incision is made on the top of the young shoot of Phragmites australis, and the young shoot of Phragmites australis is fitted with the incision of the embryo of the corn hybrid wheat using a silver needle, and the silver needle is inserted through the center of the fitted incision so that the two are penetrated and fixed together and pierced into the joint to obtain a grafted seedling;

[0065] (4) Place the fixed grafted seedlings gently in a container covered with moist filter paper and pre-cultivate for 3 days at a humidity of 81%;

[0066] (5) transferring the pre-cultivated grafted seedlings to a culture medium for seedling raising, and transplanting them after the leaves become straight and the seeds are formed, thereby cultivating asexual Phragmites australis-corn hybrid wheat;

[0067] (6) Artificially pollinating corn pollen into the pistil of asexual Phragmites-Maize hybrid wheat ears to obtain sexual Phragmites-Maize hybrid wheat, and then artificially pollinating corn pollen into the pistil of sexual Phragmites-Maize hybrid wheat ears, repeating this operation for 4 rounds, and obtaining stably expressed sexual Phragmites-Maize hybrid wheat.

[0068] Test Example 1 (one)

[0070] The Phragmites australis-corn hybrid wheat obtained by the distant hybridization breeding method of Phragmites australis and corn hybrid wheat described in Examples 1-3 was used to observe the growth conditions of the Phragmites australis-corn hybrid wheat at different stages.

[0071] The results show that the hybrid wheat with reed and corn grows well at different stages. The true leaves of the hybrid wheat with reed and corn turn yellow at night and turn green after sunrise. This may also be due to the influence of reed. In order to adapt to the low and high temperature environment, the metabolic adjustment process of reed will increase photosynthesis and related substance synthesis, so that the color of the reed leaves will change to achieve stability with the environment. Therefore, under the influence of reed, the environmental adaptability and stability of the hybrid wheat with reed and corn have been improved to a certain extent (such as Figure 4 ).

[0072] Depend on Figure 5-7 It can also be seen that the seedlings of the reed-corn hybrid wheat have vigorous growth and a well-developed root system. Using corn hybrid wheat as a control, the growth of wheat ears and grains during the grain filling period was compared. The results showed that the ears of the reed-corn hybrid wheat during the grain filling period were fuller, with more ears and larger ears (such as Figure 8 ). (two)

[0074] The stems of Phragmites australis-corn hybrid wheat at the grain filling stage were compared with the stems of Phragmites australis. Fig. 9 shown.

[0075] The results show that Phragmites australis has a guiding and regulating effect on the vascular bundle development of corn hybrid wheat stalks, making the cell division and differentiation pattern of wheat stalks gradually grow closer to Phragmites australis. The cortex of Phragmites australis corn hybrid wheat is also composed of thin-walled cells like Phragmites australis, which stores nutrients and water, providing a certain reserve for stalk growth and metabolic processes. It may also be because Phragmites australis stalk structure has a strong adaptability advantage in some aspects. In the common growth environment after grafting, corn hybrid wheat will gradually move closer to the more advantageous Phragmites australis stalk structure in order to survive and develop better, thereby affecting its cell growth and development. And then achieve better growth and increase wheat yields. (three)

[0077] After the harvest, the root system of the hybrid wheat and maize was compared with that of the reed. Fig.10 shown.

[0078] The results show that after the corn hybrid wheat and the reed bamboo are successfully grafted, the cambium stem rhizome cells of the two come into contact and fuse with each other, thereby promoting the corn hybrid wheat rhizome to develop in the structural direction of the reed bamboo rhizome, and the bamboo corn hybrid wheat root system also produces a cambium. Therefore, the reed bamboo corn hybrid wheat cultivated by the present invention has many tillers, a well-developed root system, and a strong root-like base system, which also lays a foundation for the high yield of the reed bamboo corn hybrid wheat. (Four)

[0080] The harvested Phragmites-Maize hybrid wheats were randomly selected to observe the grain conditions of the Phragmites-Maize hybrid wheats, and the single ear weight and thousand-grain weight of the Phragmites-Maize hybrid wheats were measured.

[0081] As a result, it can be obtained that the grains of the Phragmites-corn hybrid wheat cultivated by the present invention are more uniform and fuller, the thousand-grain weight can reach 65.76g, and the single ear weight can reach 10.21g.

[0082] In summary, it can be seen that the Phragmites-corn hybrid wheat cultivated by the technical solution of the present invention has the advantageous traits of both corn and Phragmites, not only has well-developed roots and strong ability to adapt to the environment, but also has significantly improved yield and quality.

[0083] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for distant hybridization breeding of Phragmites australis and corn hybrid wheat, characterized in that: The steps include: (1) soaking the selected corn hybrid wheat seeds and then performing a germination treatment; (2) when the embryo of the corn hybrid wheat grows to 2-3 cm, the embryo is cut off at an angle of 40-50 degrees upward, and an incision is made on the top of the young shoot of Phragmites australis, and then the young shoot of Phragmites australis is attached to the cut incision of the corn hybrid wheat embryo to obtain a grafted seedling; (3) pre-cultivating the grafted seedlings for 2-3 days and then transferring them to a culture medium, and transplanting them after the leaves become straight and the seeds are formed, thereby cultivating asexual Phragmites australis-corn hybrid wheat; (4) artificially pollinating asexual Phragmites-maize hybrid wheat to obtain sexual Phragmites-maize hybrid wheat; The corn hybrid wheat is a sexual corn hybrid wheat obtained by artificially pollinating asexual hybrid wheat obtained by grafting corn as rootstock and wheat as scion; the corn is a high-yield, disease-resistant glutinous corn.

2. The distant hybridization breeding method according to claim 1, characterized in that: The soaking time in step (1) is 20-22 hours.

3. The distant hybridization breeding method according to claim 1, characterized in that: The temperature of the germination treatment in step (1) is 26-28°C.

4. The distant hybridization breeding method according to claim 1, characterized in that: The step (1) includes disinfection treatment before soaking, wherein the disinfection treatment is soaking in a carbendazim solution, and the soaking time is 5-7 minutes.

5. The distant hybridization breeding method according to claim 4, characterized in that: The carbendazim solution is prepared by mixing water and carbendazim wettable powder in a mass ratio of (14-16) kg:(45-55) g.

6. The distant hybridization breeding method according to claim 1, characterized in that: The humidity of the pre-cultivation in step (3) is 80-85%.

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