Cotton leaf curl virus

The causative agent of the disease is Begomovirus gossypii, a member of the Geminiviridae family. This virus is characterized by a circular single-stranded DNA genome. It is a systemic pathogen, meaning that once the virus enters the plant, it travels through the phloem and affects the physiological pathways, leading to severe developmental abnormalities throughout the plant tissue.

The primary host for this pathogen is the cotton plant (Gossypium spp.). While cotton is the most economically significant host, the virus is known to survive in alternative weed hosts, particularly those within the Malvaceae family. These reservoirs play a critical role in the survival of the virus during the off-season, ensuring a source of inoculum for the next planting cycle.

Clinical symptoms of the infection include the characteristic upward or downward curling of the leaf margins, vein thickening, and stunted growth. Infected plants typically display shortened internodes and a bushy appearance. Because the virus disrupts nutrient transport and photosynthesis, infected plants produce fewer bolls, and the fiber quality of the resulting cotton is significantly reduced.

The transmission of Begomovirus gossypii is entirely dependent on the whitefly Bemisia tabaci. The insect acquires the virus while feeding on infected sap and transmits it to healthy plants. Environmental conditions such as warm temperatures and high humidity significantly increase the whitefly population, which in turn leads to rapid and widespread outbreaks of the disease in the fields.

Management of the disease requires an integrated approach focusing on vector control and sanitary practices:

• Implementation of strict weed control to eliminate virus reservoirs.
• Use of certified, resistant cotton cultivars where available.
• Systemic insecticide applications to manage whitefly populations during the critical growth stages.
• Adoption of crop rotation to reduce the inoculum load in the soil area.
• Monitoring of insect flight patterns to optimize the timing of protective treatments.