Transgenic Hybrid Parents in Brassica napus Transformed with Bivalent Genes for Resistance to Sclerotinia sclerotiorum

After careful study of factors that may affect transformation such as acetosyringone, pH, temperature of co-cultivation with Agrobacterium and hormones, we established an efficient and reproducible transformation method for Brassica napus. Using this protocol, we introduced β-1,3-glucanase and chitinase genes into pol-CMS hybrid parents (restorers and maintainers). Transgenic plants of restorers and maintainers were successfully obtained. PCR and Southern blot analysis revealed that both β-1,3-glucanase and chitinase gene were introduced into the genome of B. napus, and that they were inherited stably to the T₃ generation. Inoculation of detached leaves with mycelia and field assessment revealed that the resistance to Sclerotinia sclerotiorum of the T₁ and T₂ transgenic plants was stronger than that of the control line. In a 2003-2004 field assay, the disease incidence and the index of disease of the transgenic lines Peng40-12, Peng40-32 and 96B-2 was lower than that of the receptor line and resistant ‘Zhongyou821’ by 78% and 75%, respectively, was significantly lower than that of the receptor line and ‘Zhongyou821’.