Transfer And Evaluation Of Clubroot Resistance Genes Of Rapeseed(Brassica Napus L.)Variety ‘Huashuang 5’ And ‘Huahang 901’

As a large-scale vegetable with multi-functional use value,Brassica napus L.suffers serious loss of yield due to clubroot disease.Natural rapeseed oil contains high levels of erucic acid and glucosinolate,which is harmful to human body.In order to improve the resistance to clubroot disease of Brassica napus L.and the quality of rapeseed oil,In this experiment,rapeseed varieties ‘Huashuang 5’ and ‘Huahang 901’were used as recurrent parents,and cabbage resistant varieties ‘84-74’ and ‘CRShinkii’ were used as male parents to carry out breeding work of two groups.The Huashuang 5 improved variety used ‘84-74’ as the donor parent,and ‘Huashuang 5’ as the receptor parent.Based on the F1 generation,through 4 backcrossing and selfing,Using CRd gene linkage markers foreground selection,using 101 SSR markers background selection,Combining disease resistance identification and molecular marker-assisted selection techniques,plants with CRd disease resistance genes and the highest recovery of 100% recurrent parents were obtained.The Huahang 901 improved variety used ‘CRShinkii’ as the donor parent,and ‘Huahang 901’ as the receptor parent.Based on the F1 generation,through 3 backcrossing and selfing,Using CRb gene linkage markers foreground selection,using 96 SSR markers background selection,Combining disease resistance identification and molecular marker-assisted selection techniques,plants with CRb disease resistance genes and the highest recovery of 95.83% recurrent parents were obtained.In this experiment,the plants were screened to YQ-1 and YQ-2 low erucic acid markers in the ‘Huashuang 5’ BC3F1 generation and the ‘Huahang 901’ BC2F1 generation,and basically all the plants screened were restored to the maternal genome.Using the physiological race of Anhui Huangshan,Sichuan Chengdu and Yun-3 to verify the phenotypic identification of parents and F1 in two populations.The physiological race of Anhui Huangshan were selected to identify the backcross generations and F2 generations of the two groups.The results showed that the parents of Brassica napus L.were all high sensitive,the parents of cabbage were all immunized,and the F1 generations were resistant to disease.The resistance ratio of each backcross generation was close to 1:1,and the resistance ratio of ‘Huashuang 5’ BC₃F₂ generation and ‘Huahang 901’ BC2F2 generation was close to 3:1.The results showed that the transferred offspring were resistant to the physiological race of Anhui Huangshan.In order to evaluate the quality of the improved offspring,The ‘Huashuang 5’ BC₃F₂ generation and ‘Huahang 901’ BC2F2 generation was determined for agronomic traits and rapeseed quality.As a result,the agronomic traits and quality traits of the improved offspring were basically the same as the double low maternal,and the erucic acid and glucosinolate contents were all in accordance with the double low standard.The ‘Hua Shuang 5’ BC₃F₂ generation has a yield of 0.72 kg,and the ‘Huahang 901’ BC2F2 generation has a yield of 0.45 kg.The former is better than the latter.The soluble sugar content of ‘Huashuang 5’ BC₃F₂ generation is about 1.75%,and the content of Ve is about 17.93%;the soluble sugar content of ‘Huahang 901’ BC2F2 generation is about 2.74%,and the content of Ve is about 30.12%.The latter is better than the former.