Somatic embryogenesis and Agrobacterium-mediated genetic transformation of geranium with chitinase-glucanase encoding genes Mohandas Sukhada*, Kempaiah Prakasha, Choudhary M.L.1, Horticulture Commissioner, Murthy B.N.S., Gowda T.K.S.2 Indian Institute of Horticultural Research, Hessaraghatta, Bangalore, 560 089. *Corresponding author's: E-mail: sukhada@iihr.ernet.in
1Government of India, New Delhi, 110 001. 2University of Agricultural Sciences, G.K.V.K., Bangalore, 560 065. Abstract Geranium (Pelargonium x hortorum) is a popular floricultural crop worldwide. This crop is attacked by various pathogenic fungi causing wilt and tip rots. Regeneration of ornamental geranium (Pelargonium x hortorum var Scarlet) was achieved through somatic embryogenesis using hypocotyl segments. The highest number of somatic embryos (12.60) per explant were obtained on MS medium containing 1.5mM thidizuron (TDZ) and somatic embryogenesis initiation was achieved in 14 days. Stable transgenic plants were obtained by co-cultivation of hypocotyls with Agrobacterium tumefaciens strains LBA 4404 harbouring the recombinant binary vector pBINAR vector containing chitinase-glucanase encoding gene. Transformants were selected using kanamycin (100 mg/l). Transgenic integration was confirmed by PCR and by southern blot analysis. Glucanase activity in the leaf of primary transformants was nearly double compared to non-transformed leaves. In-vitro testing of Fusarium growth by crude protein of transformed leaves showed 1.5 cm diameter of inhibition zone as against non-transformed leaves where it was 0.5 cm. The combined expression of these plant-defence proteins should be able to enhance the plant's resistance to fungal attack. Top Key words Somatic embryogenesis, transformations, glucanase, chitinase, PCR. Top |