Transgenic beans (Phaseolus vulgaris L.) engineered to express viral antisense RNAs show delayed and attenuated symptoms to bean golden mosaic geminivirus

The genes Rep-TrAP-REn and BC1 from the Brazilian isolate bean golden mosaic geminivirus (BGMV-BR) were cloned in antisense orientation under the transcriptional control of the CaMV 35S promoter. This construct was used to transform common bean (Plaseolus vulgaris L.) using the biolistic method. Transgenic plants from the R-3 and R-4 generations were challenged by inoculation with a BGMV-BR viruliferous whitefly population. Of the four transgenic lines tested, two had both delayed and attenuated viral symptoms. Un-transformed plants or plants transformed with a construct containing only the gus-neo gene developed typical BGMV-BR symptoms 10-15 days after inoculation.