Control of Disease Induced by Tospoviruses in Tomato: An Update of the Genetic Approach

Abstract

Advances in the search for genetic resistance to tospoviruses affecting tomato crops are reviewed. The
economic losses caused by Tomato spotted wilt tospovirus (TSWV), the great number of hosts it affects and its wide
distribution around the world has made TSWV one of the ten most important plant viruses. Other viruses in or
related to the same genus also cause severe damage, although their presence in the world is much more localized.
Due to the limited effectiveness of physical, chemical and biological control methods, the use of genetic resistance for
control is the best management strategy on a medium-long term basis. Given the relative ease with which new TSWV
isolates that overcome existing genetic resistance are generated, it is of prime importance to continue the search for new
sources of resistance, as well as to promote a better exploitation of available ones. A better understanding of the mechanisms
causing resistance and of their genetic control, as well as the identification of molecular markers linked to
resistance genes, would enable the pyramiding of different resistance genes. This would be a positive contribution to the
development of a greater and more durable resistance. It is also necessary to further the study of genetic resistance to
other viruses of the genus Tospovirus, as globalisation can speed up their distribution throughout the world.