A new begomovirus infecting pepper plants in Cuba

Diseases caused by begomoviruses are a major threat to vegetable production for countries in the Caribbean and Central America. In 1996, an isolate of Tomato yellow leaf curl virus (TYLCV) was reported to be affecting tomato plants (Lycopersicon esculentum) throughout Cuba (Martínez et al., 1996). In 2002, the same virus was detected in pepper (Capsicum annuum) in Camagüey, Sancti Spíritus and Havana provinces and in bean (Phaseolus vulgaris) plants in Havana province (Martínez et al., 2002; Quiñones et al., 2002).

During a survey in 2005, in the pepper production areas of eastern Cuban, about 70% of pepper plants growing at an Experimental Station in Holguin province, showed symptoms that differed from those previously described for TYLCV in pepper. Symptoms consisted of plant stunting and a severe leaf yellow mosaic with crinkling and curling. Ten representative symptomatic plants were collected and leaf samples analyzed by transmission electron microscopy. Total nucleic acid was extracted and assayed by non-radioactive nucleic acid hybridisation, using a TYLCV intergenic region probe under low stringency conditions (Quiñones et al., 2002) and by polymerase chain reaction (PCR). All leaf samples showed the presence of typical geminivirus particles, whereas none exhibited hybridisation signals. Using PCR with degenerate primers that specifically amplify the coat protein region from begomoviruses (Wyatt & Brown, 1996), all samples produced amplicons of the expected size (576bp). PCR amplicons from three samples were cloned in pGEM T-Easy vectors (Promega). The clones were sequenced and BLAST analysis showed the highest identity (98%) within clones; between 93% and 94% identity with Cabbage leaf curl virus (U65529 and AF065815, respectively) and between 87% and 90% identity with Pepper yellow vein virus (AF 063139), Pepper golden mosaic virus (AY368336) and Texas pepper mosaic virus (AF077025). However there was only 68% identity with TYLCV (AJ223505). One of the sequences was deposited in GenBank (DQ207808) as representative of the three clones. This report shows the occurrence of a new begomovirus in pepper plants in Cuba.