Overview of begomovirus genomic organization and its impact

More than 80% of the known geminiviruses are transmitted by whiteflies (Bemisia tabaci Gennadius) and belong to the genus Begomovirus, which mostly have bipartite genomes designated as DNA-A and DNA-B and infect dicotyledenous plants although numerous begomovirus with a monopartite genome occur in the Old World and there are some of which a single components is not infectious yet no DNA-B component has been found. There have been several of reports of satellite molecules associated with begomoviruses. Genome ORFs are plays important roles for host range determination, virus symptom development & severity, virus movement and virus replication. The frequency with which new begomoviruses are appearing shows that these viruses are still evolving and pose a serious threat to sustainable agriculture, particularly in the tropics and sub-tropics. In recent years, some begomoviruses have also moved to temperate regions causing concern in the production of vegetables in greenhouses. In this review we have discus about the genome organization of begomovirus, its ORFs and their possible pathogenesis n the basis of research findings.