Jatropha yellow mosaic virus

The causative agent of this disease is Begomovirus jatrophaflavamusivi, a member of the Geminiviridae family. It is a DNA virus characterized by twin (geminate) particles. The virus interferes with the host plant's physiological functions by altering the expression of genes involved in chloroplast development and cell division.

The primary host for this viral pathogen is Jatropha curcas, a versatile plant used in biofuel production and medicinal industries. The virus also relies on various weeds within the Euphorbiaceae family, which act as alternative hosts, ensuring the virus persists in the environment even when primary crops are absent.

Diagnostic symptoms are primarily localized on the leaves, presenting as typical yellow mosaic patterns, leaf yellowing, and chlorosis. Infected plants exhibit stunted growth, reduced internode length, and distorted, crumpled leaves. These symptoms lead to reduced biomass production and significant yield losses in commercial plantations.

The virus is transmitted in a persistent circulative manner by the whitefly Bemisia tabaci. Environmental factors that promote whitefly proliferation, such as warm, humid climates, significantly increase the incidence rate of the disease. The virus spreads rapidly across fields as vectors migrate between healthy and infected host plants.

Effective management requires an integrated pest management (IPM) approach. This involves the application of systemic insecticides to control whitefly populations, the immediate rouging of infected symptomatic plants, and the use of certified virus-free germplasm. Furthermore, maintaining field hygiene and clearing surrounding weeds reduces the primary inoculum levels.