Sexual polyploidization breeding method of tetraploid Brassica campestris ssp.chinensis Makino

Abstract

The invention belongs to the field of crop breeding and discloses a sexual polyploidization breeding method of tetraploid Brassica campestris ssp.chinensis Makino. The method comprises the following steps of: treating flower buds by using solution of colchicine in the bolting period of the Brassica campestris ssp.chinensis Makino to induce the flower buds to generate 2n male gametes; and performing manual sexual polyploidization cross breeding on a tetraploid male sterile line serving as a female parent and 2n male gamete-containing diploid obtained by the induction of the solution of colchicine serving as a male parent in a blooming period to obtain the tetraploid Brassica campestris ssp.chinensis Makino. In the method, a sexual polyploidization breeding approach of hybridizing the male sterile line of the tetraploid Brassica campestris ssp.chinensis Makino with the diploid Brassica campestris ssp.chinensis Makino which generates 2n gametes after induction is used for the first time to obtain a new species of the tetraploid Brassica campestris ssp.chinensis Makino which has wider genetic diversity and higher seed setting rate compared with the autotetraploid of asexual polyploidization. The new tetraploid of the invention has the characteristics of polyploid such as largeness, disease resistance and cold resistance, high quality, and the properties of a diploid male parent.

Description

technical field [0001] The invention belongs to the field of crop breeding, and relates to a sexual polyploidy breeding method for tetraploid non-heading Chinese cabbage, which is specially used for the selection and breeding of tetraploid non-heading Chinese cabbage. technical background [0002] There are two polyploidization pathways in the evolution of species in nature. One is sexual polyploidy, and the other is asexual polyploidy. The former is the main way for plant polyploidy to form in nature, that is, through the formation of 2n gametes, and then participate in sexual mating. Sexual polyploidy of 2n gametes has more biological advantages, higher occurrence frequency and higher heterozygosity than asexual polyploidy. Introgression from sib diploids creates genetic diversity and results in genetically heterozygous polyploid populations. Polyploid breeding with 2n gametes can combine different genotypes at an increased ploidy level, providing the possibility to pass...

AI Technical Summary

Problems solved by technology

At present, there is no use of colchicine to induce diploid non-heading Chinese cabbage to produce 2n male gametes in the prior art at home and abroad, and then cross with tetraploid non-heading Chinese cabbage cytoplasmic male sterile lines to obtain new tetraploids. sexual polyploidy breeding technology

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