African cassava mosaic

African cassava mosaic is a devastating plant disease caused by viruses from the Geminiviridae family. It represents a major constraint on cassava production globally, particularly in sub-Saharan Africa, leading to significant yield losses and food shortages in vulnerable regions.

The primary host for this pathogen is the cassava plant (Manihot esculenta). However, agricultural research has highlighted its potential to affect other crops, including soybean, which necessitates rigorous monitoring of host ranges to prevent potential cross-crop outbreaks.

Symptoms of the infection typically include leaf yellowing (chlorosis), mosaic patterns, leaf distortion, and stunted plant growth. In severe cases, the infected plants remain significantly smaller than healthy ones, and their root development is drastically suppressed, leading to reduced harvestable tubers.

The virus is primarily transmitted by the whitefly Bemisia tabaci and through the use of infected cuttings during propagation. Environmental conditions such as warm temperatures and high humidity promote the population growth of whiteflies, thereby facilitating rapid disease dispersal.

Management of African cassava mosaic relies heavily on an integrated approach. The most critical measures include the deployment of resistant varieties, the use of virus-free vegetative propagation material, and the timely application of systemic insecticides to manage whitefly vector populations.

• Deployment of resistant cassava cultivars.
• Establishment of strict phytosanitary measures.
• Rogueing of infected plants in early stages.
• Integrated pest management targeting Bemisia tabaci.