Agrobacterium tumefaciens-mediated Transfer of a-tubulin: rolB Gene for Inducing MaleSterility in Oilseed rape (Brassica napus L.)
Gupta Rashmi, Gahalain S.S.
Department of Botany, Kumaun University, SSJ Campus, Almora-263 601, Uttaranchal, India.
Transgenic plants of oilseed rape (Brassica napus L.) were obtained from hypocotyl explants using Agrobacterium tumefaciens vectors. Induction of a dominant nuclear male sterility was studied in the progenies of 28 transformed plants through the expression of ro/B gene under the control of a.tubulin promoter inserted in the plasmid pGA1329. The chimeric a.-tubulin: rolB gene was linked to the neomycin phosphotransferase (NPTII) gene, conferring resistance to the antibiotic kanamycin, was used as a dominant marker for the induced male sterility. The expression and inheritance of the transgene was confirmed in the progenies of 23 transformants through kanamycin-resistance. In the progeny, a Mendelian ratio of 1:1 was observed for male sterile/kanamycin-resistant and male fertile/kanamycin-susceptible plants. There were no prominent morphological changes in the flowers of transformed male sterile plants as compared to the control male fertile plants. At microsporegenesis, simultaneous degeneration cell contents of tape'tal cell and microspores; and at anthesis, sterile pollen grains contained only empty exine.