Begomovirus ssDNA plant virus (family Geminiviridae) replication within the Bemisia tabaci vector is controversial. Transovarial transmission, alteration to whitefly biology, or detection of viral transcripts in the vector are proposed as indirect evidence of replication of tomato yellow leaf curl virus (TYLCV). Recently, contrasting direct evidence has been reported regarding the capacity of T...

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...

Plants including pepper, red kidney bean, squash, string bean and tomato, as well as weeds with viral symptoms were collected from five districts in Belize over a three year period with the aim of determining the diversity of the begomoviruses present. Sixty five percent of the samples screened via DNA hybridization produced signals indicative of begomovirus infection. Subsequent PCR amplificat...

Begomoviruses (Geminiviridae) are serious plant pathogens infecting dicotyledonous plants among important crop plants. The majority of the members comprises bipartite genomes (DNA A and B), encapsidated in twin particles and transmitted by the whitefly-vector Bemisia tabaci. Cassava (Manihot esculenta, Crantz) production is restricted by begomovirus inducing Cassava mosaic disease (CMD) in Afri...

Sweetpotato is an important crop for food security in many developing countries. Surveys have consistently listed virus diseases, especially sweetpotato virus disease (SPVD), as the most important diseases of this crop, yet they remain the most difficult diseases to manage. Much has been learned about sweetpotato viruses from independent research programs in different countries in recent years....

Some geminiviruses are transmitted by the whitefly Bemisia tabaci in a circulative manner. These geminiviruses are assigned to the genus Begomovirus within the family Geminiviridae. The route followed by begomoviruses in their insect vector and the velocity of translocation of the various viruses seem to be intrinsic to the whitefly, not to the virus. Subsequent to ingestion during feeding on a...