Malvastrum leaf curl begomovirus

Begomovirus malvastrumhelshirense is a viral plant pathogen belonging to the Begomovirus genus within the Geminiviridae family. These viruses are characterized by their circular single-stranded DNA genomes and are well-known for causing devastating diseases in various agricultural crops worldwide, primarily through the disruption of normal plant growth and development.

The virus primarily affects plant species within the Malvaceae family, such as Malvastrum, cotton, and hibiscus. In intensive agricultural systems, the presence of this virus can lead to severe economic losses due to reduced yields, stunted plant growth, and the loss of aesthetic value in ornamental horticultural crops.

The disease symptoms typically include severe curling of the leaves, vein clearing, and yellow mosaic patterns. Affected plants often exhibit shortened internodes, which gives them a stunted or bushy appearance. The physiological impact is profound, as the infection interferes with photosynthesis and nutrient transport, leading to a significant reduction in biomass production.

Transmission occurs exclusively through the whitefly Bemisia tabaci in a persistent manner. The virus is acquired by the whitefly during feeding on an infected plant and is subsequently transmitted to healthy plants. The efficiency of transmission is highly dependent on the population density of the whiteflies and local environmental conditions that favor the insect vector's reproduction.

Management of this viral infection is challenging because there is no cure for infected plants. Therefore, integrated pest management (IPM) strategies are essential to minimize the risk of spread:

• Strict weed control to eliminate alternative hosts for both the virus and the whitefly vector.
• Use of virus-free planting material and resistant crop varieties.
• Deployment of physical barriers, such as insect-proof nets, in protected cultivation.
• Timely application of systemic insecticides to control the whitefly population at the early stages of infestation.
• Implementation of crop rotation and fallow periods to break the pathogen's lifecycle.