0000000000930378
AUTHOR
Davino
Two new natural begomovirus recombinants associated with the tomato yellow leaf curl disease co-exist with parental viruses in tomato epidemics in Italy
Two tomato geminivirus species co-exist in protected crops in Sicily, Tomato yellow leaf curl Sardinia virus (TYLCSV, found in 1989) and Tomato yellow leaf curl virus (TYLCV, found in 2002), and mixed infections have been detected. In a field survey conducted in 2004, the viral intergenic region (IR) was amplified from infected plants, and molecules apparently hybrid between the two species were found, but only in plants where one or both parental species were also present. Two of these hybrids, named 2/2 and 2/5, were isolated and infectious clones were obtained. They were both readily whitefly-transmitted to tomato plants; clone 2/5 produced symptoms typical of TYLCSV and TYLCV, while clo…
A single tube PCR assay for detecting viruses and their recombinants that cause tomato yellow leaf curl disease in Mediterranean basin
Tomato yellow leaf curl disease (TYLCD) is well known in Mediterranean countries, where it has been causing severe losses in tomato crops for decades. Until recently, two viruses (with several isolates) in the genus Begomovirus, family Geminiviridae, have been associated with the epidemics: Tomato yellow leaf curl virus (TYLCV) and Tomato yellow leaf curl Sardinia virus (TYLCSV). However, recombinants between these, such as Tomato yellow leaf curl Malaga virus (TYLCMalV), are spreading, and new methods for detecting all viruses present in the region are needed. By considering all DNA sequences available of viruses causing TYLCD in the Mediterranean basin, a PCR/RFLP protocol was developed t…
Spread of tomato yellow leaf curl virus in Sicily: partial displacement of another geminivirus originally present.
The geminivirus Tomato yellow leaf curl virus (TYLCV) was reported for the first time in Italy in 2002. We have followed its spread in Sicily, where Tomato yellow leaf curl Sardinia virus (TYLCSV), another tomato-infecting geminivirus, is endemic and has been causing severe crop losses since 1989. The presence of the two viruses was monitored in the main tomato growing area, the Ragusa province, analyzing samples with yellow leaf curling symptoms. At first (spring-summer 2002) both viruses were always found in mixed infections, but in 2003 and 2004 18-35% of plants were found infected by TYLCV alone and 8-28% by TYLCSV alone, with 41-69% carrying both viruses. TYLCV has spread quickly in th…