Production and evaluation of SCMV resistant transgenic sugarcane pests derived from transformed callus : SRDC final report BS94S

Abstract

We have successfully demonstrated that sugarcane can be genetically engineered for resistance to sugarcane mosaic virus, using the coat protein gene of the virus to mediate resistance. At present the frequency of plants showing moderate to high transgene-mediated resistance to viral infection is low, but the second generation of constructs with stronger promoters should address this issue. Transgenic sugarcane plants of cultivars Q95, Q153 and Q155 that contained a sugarcane mosaic coat protein gene construct under control of the Emu promoter were produced. These plants were regenerated from embryogenic callus which had been co-transformed by microprojectile transformation with the coat protein gene construct and the neomycin phosphotransferase II (NPT II) selection gene. The plants were established in the PC2 glasshouse at the Pathology Farm, Eight Mile Plains and were then mechanically inoculated with an inoculum of sugarcane mosaic virus prepared from infected sugarcane grown at the Pathology Farm. One transgenic line of Q155 did not develop mosaic symptoms over the time course of the trial, while another 6 lines of cultivars Q95, Q153 and Q155 showed a delay in the development of symptoms. Molecular analysis of these lines by PCR indicated the presence of both the NPT II and CP genes. Further analysis of selected lines by Southern blot hybridisation indicated the presence of one to three copies of the CP gene.