Some biological and genomic properties of pigeonpea isolate of mungbean yellow mosaic geminivirus.
The causal virus of yellow mosaic of pigeonpeas (Cajanus cajan) was found to be an extended host range phenotype of mung bean yellow mosaic bigeminivirus (MYMV). The pigeonpea isolate (MYMV-Pp) was transmitted by whitefly (Bemisia tabaci) to mung beans (Vigna radiata), black gram (Vigna mungo), French bean (Phaseolus vulgaris), soyabeans (Glycine max), lima beans (Phaseolus lunatus), horse gram (Macrotyloma uniflorum) and cowpeas (Vigna unguiculata). Double stranded DNA forms (open circular, linear and supercoiled) from infected plants were purified and cloned into pUC18 and pBluescript SK+ vectors; 4 full length clones were obtained. All 4 were DNA-B (on the basis of hybridization with MYMV-Bg DNA-B). Restriction analysis of clone pMY-PB3 revealed that it had a pattern similar to that of MYMV-Bg (black gram isolate) DNA-B, suggesting that MYMV-Bg and MYMV-Pp1 are closely related. DNA-B of MYMV-Pp1 differed considerably in its restriction maps from that of MYMV-T, a mechanically transmissible isolate characterized from Thailand. DNA-B probes detected MYMV-Pp1 in the plants, and in adults and pupae of viruliferous whiteflies.