Identification of Cotton leaf curl Multan virus, a new threating Begomovirus in Iran

Chinese hibiscus, Hibiscus rosa-sinensis L., is a common ornamental shrub in warm and humid regions of Iran like Khuzestan province, southwestern Iran. During 2019, some Chinese hibiscus plants showing begomovirus like symptoms including vein enation and leaf cupping (Figure 1A) were observed in Ahvaz, Khuzestan province. New plants obtained from cuttings of symptomatic plants showed the same symptoms. Leaf samples were collected and the extracted total DNA was subjected to polymerase chain reaction (PCR). Degenerate primer pairs were used to detect DNA A and DNA B genomic fragments of begomoviruses and their associated betasatellites. PCR resulted to amplify ~500 bp fragment of DNA A (complete V2 and partial V1 ORFs) while DNA B as well as betasatellite were not detected. Amplified fragments were purified and sequenced in both virion and complementary sense. Analyses performed using the Blastx program indicated that the DNA sequences have 93 to 96% pairwise identity with isolates of Cotton leaf curl Multan virus. Phylogenetic analysis revealed host preference between different analyzed begomovirus isolates so that cotton leaf curl viruses originated from H. rosa-sinensis like Khuzestan isolate of CLCuMuV formed a separated cluster. To our knowledge, this is the first report of CLCuMuV incidence in Iran. Considering the widespread presence of the begomovirus whitefly vector in the country, this virus that can be a serious threat to other economically important crops in Iran.