Chitinase gene transformation through Agrobacteriumand its explanation in soybean in order to induce resistance to root rot caused by Rhizoctonia solani.

Chitinase gene (chi) of bean which has been cloned in recombinant binary plasmid vector, pBI121 with 35s promoter of Cauliflower mosaic virus (CaMV), were used for transformation of soybean using strain LBA4404 of Agrobacterium. The plasmid contained nptII gene that is a resistant gene to kanomycin as selector marker and Gus gene as reporter. Cotyledon explants of Williams and Clark cultivars were inoculated by Agrobacterium suspension with pBI121 and were cultured in regeneration medium. After complete regeneration of explants to seedling in B5 medium amended with kanomycin, polymerase chain reaction analysis were conducted to ensure conjugation of nptII, Gus, CHN genes in transformants seedling of soybean. Results showed that some lines of soybean contained Gus and CHN genes. More ever, chitinase activity in leaf extract of transformed soybean lines was significantly more than untransformed soybean, exception one sample. Bioassay of chitinase activity of transgenic lines on in vitro condition prevented mycelial growth of Rhizoctonia solani in comparison with untransformed control leaf extract.