Global Scenario of Begomovirus Diseases in Vegetable Crops

Abstract

Whitefly-transmitted begomoviruses are the major threats to the cultivation of vegetable crops worldwide. Begomoviruses infecting vegetables have a broad host range and are distributed among all continents in which vegetables are grown in open fields and protected structures. In most of cases these begomoviruses are commonly found in mixed infections of more than one virus leading to the emergence of new variants/species which is found to be adapted to different hosts in various geographical regions. Mainly the evolution of begomoviruses occurs through point mutation, intra and interspecies recombination and reassortment. The association of satellite molecules such as beta- and alpha-satellites helps in altering the virulence of the helper begomoviruses. Till date there are about 243 begomovirus species are found to be infecting vegetable crops in the global scenario. Further, these vegetable-infecting begomoviruses exhibited diversity in the phylogenetic analysis. They are clustering based on their number of genomic components (monopartite/bipartite), host they are infecting and their geographical origins. The objective of the review is to present the global scenario of the begomoviruses infecting vegetable crops on the aspects of symptomatology, genome organization, taxonomy, diversity, diagnostics, host range and possible management strategies to combat the virus infection.

The Role of Satellites in the Evolution of Begomoviruses

“…The estimated economic loss due to begomoviruses in the 1990s was USD 1.3–2.3 billion for cassava in Africa, USD 5 billion for cotton in Pakistan, USD 300 million for grain legumes in India, and USD 140 million in Florida, USA, for tomato alone [ 1 ]. Despite efforts to contain begomoviruses, they continue to emerge and re-emerge in diverse crops and regions [ 2 , 3 , 4 , 5 , 6 , 7 ].…”