Breeding method for repairing and improving natural doubling rate of maize haploid male flower by utilizing recurrent selection

Abstract

The invention discloses a breeding method for repairing and improving a natural doubling rate of maize haploid male flower by utilizing recurrent selection, belonging to the field of maize breeding methods. The breeding method disclosed by the invention comprises the following steps: constructing an excellent base population, then generating a haploid by utilizing an inducing line, and carrying out doubling so as to obtain a double haploid (DH) line; and selecting a double haploid (DH) line hybridization group with complementary characters and strong pollinating ability so as to form a new round of a population, and carrying out recurrent selection so as to continuously improve the natural doubling rate of the haploid male flower. The method provided by the invention can significantly improve the natural doubling rate of the maize haploid male flower, wherein the natural doubling rate of the fourth round can maximally reach to 90% or above; moreover, the method provided by the invention overcomes the technical bottleneck of haploid breeding, and can increase the breeding efficiency of the double haploid (DH) line by a hundred times or above compared with the prior art; the method provided by the invention also has the advantages of no toxicity, rapidness, high efficiency, environmental protection, etc., and completely gets rid of a conventional highly-toxic, complicated and inefficient artificial doubling method; in addition, the excellent double haploid (DH) line selected from every round in the method provided by the invention can directly enter a commercial breeding procedure.

Description

technical field [0001] The invention belongs to the field of corn breeding methods, and in particular relates to a breeding method for improving the natural doubling rate of maize haploid male flowers by genetic repair using a recurrent selection method Background technique [0002] At the beginning of the 21st century, the three major breeding technologies of rapid haploid homozygosity, molecular marker-assisted selection, and transgenics were gradually recognized by maize breeders all over the world, and were quickly and comprehensively applied. In particular, double haploid breeding technology has the most rapid development in my country due to its outstanding advantages that cannot be compared with conventional pedigree methods, such as short time consumption, low cost, and high degree of homozygosity, and is widely used in commercial breeding, which has promoted the leapfrogging of maize breeding in my country style development. [0003] At present, it is not difficult ...

AI Technical Summary

Problems solved by technology

However, the artificial doubling method has the following problems: first, there is no ideal doubling agent, and the effect of low-toxicity chemical agents is poor, so it is difficult to achieve the ideal doubling effect; although the doubling effect of colchicine is good, it is a highly toxic and strictly controlled medicine, which is toxic to humans and animals. Large, human contact can easily cause cell malignant transformation, and it will cause great environmental pollution, resulting in high seedling mortality during the treatment process; secondly, the method is complicated and the operation level is extremely high; in addition, the cost of manual doubling is high

[0006] After searching, no non-toxic and efficient method for increasing the natural doubling rate of maize-induced haploid male flowers has been found

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