Our current knowledge concerning the transmission of begomoviruses by the whitefly vector Bemisia tabaci is based mainly on research performed on the Tomato yellow leaf curl virus (TYLCV) complex and on a number of viruses originating from the Old World, such as Tomato leaf curl virus, and from the New World, including Abutilon mosaic virus, Tomato mottle virus, and Squash leaf curl virus. In t...

Evidence for the involvement of a Bemisia tabaci GroEL homologue in the transmission of tomato yellow leaf curl geminivirus (TYLCV) is presented. A approximately 63-kDa protein was identified in B. tabaci whole-body extracts using an antiserum raised against aphid Buchnera GroEL. The GroEL homologue was immunolocalized to a coccoid-shaped whitefly endosymbiont. The 30 N-terminal amino acids of ...

Whiteflies cause damages to many economically important agricultural crops because of their feeding habits and their begomovirus transmissions. The whitefly Bemisia tabaci is a genetically diverse group, which includes a large number of different biotypes (see Part I, Chapter 3). It is extremely prolific; a single female may lay approximately 400 eggs during her lifetime. Unfertilized eggs give...

Tomato yellow leaf curl China virus (TYLCCNV) is a monopartite begomovirus associated with different betasatellites. In this study, we investigate two different isolates of Tomato yellow leaf curl China betasatellite (TYLCCNB) to determine what features of the viral genome are required for induction of characteristic phenotypic differences between closely-related betasatellite. When co-agroinoc...

The female-biased infection of facultative symbionts has been found in Bemisia tabaci; however, whether there are any differences in tomato yellow leaf curl virus (TYLCV) and obligate symbiont infection rates between females and males is unknown. Determining whether such differences exist would be very important for understanding the spread of the plant virus and of the symbionts. We compared b...

Circular single-stranded DNA (ssDNA) viruses are the smallest viruses known to infect eukaryotes. High recombination and mutation rates have conferred these viruses with an evolutionary potential that has facilitated their emergence. Their damaging effects on livestock (circoviruses) and crops (geminiviruses and nanoviruses), and the ubiquity of anelloviruses in human populations and other mamm...

The genome of the tomato yellow leaf curl virus (TYLCV), a Bemisia tabaci-transmitted geminivirus, was cloned. All clones obtained were of one genomic molecule, analogous to DNA A of African cassava mosaic virus. Nucleotide sequence analysis of the TYLCV genome showed that it comprises 2787 nucleotides, encoding six open reading frames, two on the virion strand and four on the complementary str...

Kenaf (Hibiscus cannabinus L.) is a malvaceous bast fibre crop and the most promising source of “tree-free” newsprint in the world. For the last few years a begomovirus associated leaf curl disease of kenaf, characterized by upward leaf curling and stunted growth, has been observed at different locations in India. In this study biological and molecular analyses of kenaf leaf curl disease-associ...