Thrips-tospovirus interactions: biological and molecular implications

Abstract

The occurrence of thrips vectors in considerable numbers enables their functioning in a dual role as vectors and as direct crop pests. The resistance of thrips to pesticides has enabled quick transmission of viruses, the transient nature of their populations being essentially responsible for the infection. The feeding behaviour of thrips contributes in a large measure towards their ability to act as vectors, enabling leaf-to-leaf transmission of the tospoviruses. The specific association of the tospoviruses and thrips vectors, particularly relating to the molecular profiles, needs increasing scrutiny to come to proper conclusions. A better understanding of the nature of virus multiplication and the pathways leading to their entry into the salivary glands and the ability of the second instar larvae to inoculate plants need further inputs. The intraspecific diversity of thrips vectors as a result of population studies from various parts of the country, would further enable a better understanding of the ability of each species to transfer the virus, besides better appreciation of the chemical ecology of thrips-host-plant interaction, not to mention the relevance of serodiagnosis in detecting disease or health.