Blackgram mottle virus

Blackgram mottle virus (BGMV) is a significant plant pathogen belonging to the genus Sobemovirus. It is a single-stranded RNA virus primarily known for causing systemic diseases in various legume crops, particularly in regions where black gram and mung bean are cultivated extensively.

The disease is characterized by typical mosaic symptoms, chlorosis (yellowing), and leaf curling. Plants infected with BGMV exhibit stunted growth, reduced leaf size, and significant yield losses due to impaired pod formation and poor seed filling. The pathogen interferes with the plant's metabolic processes, affecting overall vigor and crop development.

The transmission cycle of BGMV relies heavily on biological vectors. The most common vectors are beetles (such as species from the Chrysomelidae family), which acquire the virus while feeding on infected tissue and transmit it to healthy plants. Mechanical transmission can also occur in fields via contaminated tools or direct plant-to-plant contact, facilitating the rapid spread of the disease.

Environmental conditions, particularly warm temperatures and high humidity, play a critical role in the virus's spread by promoting vector activity and survival. The virus can persist in alternative weed hosts or agricultural debris during the off-season, which serves as a source for primary inoculum for the next crop cycle.

Integrated disease management for BGMV includes the following strategies:

• Utilizing genetically resistant or tolerant crop varieties.
• Implementing strict weed control to eliminate virus reservoirs.
• Applying insecticides to manage beetle populations and reduce vector pressure.
• Practicing crop rotation to break the virus infection cycle.
• Ensuring the use of high-quality, virus-free seeds for planting.