Breeding Of A Cytoplasmic Male Sterility And Its Maintainer Line In Broccoli (Brassica Oleraceal Var. Italica Pleach)

Broccoli(Brassica oleraceal var. italica pleach) is variety of Brasica oleracea in Cruciferae.has been an important vegetable in China. Hybrids Fl seed was produced by male sterile line, becoming a major trend in broccoli breeding. So we introduced cytoplasmic male sterility line of Brassica napus as sterility source, and take inbred line of broccoli as recurrent parent for backcross breeding, researched distant hybridization, tissue culture of sterile plants and maintenance line seed reserved in this study.1. Choosing the cytoplasmic male sterility line of Brassica napus as an sterility source, after multiple generation of backcrossing, we transferred cytoplasmic male sterility cytoplast of Brassica napus to broccoli. got a stable broccoli CMS line and its maintainer line.2. We used in vitro ovary culture method to overcome decline of hybrid embryos of Brassica napus and broccoli, obtained hybrid progeny by tissue culture technology. The results showed that:the ovary after pollinated 15d had the best culture effect, got 7 full seeds.and the germination rate was 0.29, with an average of 0.17 available hybrids per pod and germination rate 66.7% in medium.Comparing traits of parental and hybrid progenies, biological characteristics of hybrid progeny were partial to male.3.The receptacle and inflorescence of broccoli were used as explants for tissue culture, the results showed that:the induction rate of different broccoli varieties ranged from 2.3% to 83.3%, multiplication coefficient was 5.98, and rooting rate was 91.7%, the average root number was 13.0. Using the whole light automatic spray cultured plantlet. the survival rate was up to 100%.4. We explored the effect of different planting time to the impact of agronomic traits of broccoli maintain line, the results showed that with the planting dates delay, harvest time was delayed and flowering time was in advance. Plant height, leaf area, curd quality, seed quality and seedling quality had deteriorated; Incidence rate of black rot had reduced. The effect of different planting time to seed setting rate were different among the different varieties.