GENOME HOMOLOGIES AMONG GEMINIVIRUSES INFECTING VIGNA, CASSAVA, ACALYPHA, CROTON AND VERNONIA

Acalypha indica, Croton sparsiflorus and Vernonia cinerea, that grow a round Vigna radiata and Vigna mungo fields and exhibit viral symptoms, were tested whether they serve as the reservoirs of Vigna yellow mosa ic virus (YMV), a geminivirus. DNA A of Indian cassava mosaic virus (I CMV) was used as a general probe and DNA B of ICMV and YMV were used a s specific probe, ICMV DNA A hybridized intensely to DNA from infected V. radiata, V. mungo, A. indica, C. sparsiflorus and V. cinerea, indi cating that all these plants harboured whitefly-transmitted geminiviru ses. The presence of single-stranded virion DNA and double-stranded re plicative form in these plants was characterized by non-denaturing Sou thern analysis and by nuclease-sensitivity analyses, DNA B of ICMV, a specific probe, hybridized only to DNA from infected cassava and Acaly pha suggesting that the geminiviruses that infected cassava and Acalyp ha are related. DNA B of YMV hybridized only to the DNA from infected V. mungo and V. radiata but not to the DNA of any of the weeds. Our re sults show that geminiviruses that infect the weeds A. indica, C. spar siflorus and V. cinerea are not related to Vigna YMV and do not serve as reservoirs of V. mungo YMV.