Bean yellow mosaic virus

Bean yellow mosaic virus (BYMV) is a significant plant pathogen belonging to the genus Potyvirus within the family Potyviridae. It is recognized as one of the most widespread viruses affecting legumes, capable of causing systemic infection and severe yield losses in agricultural ecosystems globally.

The virus has a wide host range, primarily infecting members of the family Fabaceae, such as Phaseolus vulgaris (common bean), Pisum sativum (pea), Glycine max (soybean), and Trifolium species (clover). In addition to legumes, it can infect various ornamentals, including gladioli, and several weed species that act as perennial reservoirs for the virus.

The biological cycle is driven by insect vectors, specifically aphids. The virus is transmitted in a non-persistent, stylet-borne manner, meaning the aphid acquires the virus during short feeding probes and transmits it immediately to a healthy host. Transmission can also occur mechanically through contaminated equipment or, in some cases, via infected seeds, facilitating the spread of the disease.

Development and spread of the disease are highly correlated with aphid population dynamics. Favorable conditions, such as mild temperatures, accelerate the migration of vectors between host plants. Typical symptoms include distinct yellow-green mosaic patterns on leaves, stunted growth, deformation of plant tissues, and a reduction in both the quantity and quality of pods and seeds.

Effective management requires an integrated approach to mitigate the virus's impact. Key strategies include:

• planting virus-resistant or tolerant cultivars;
• controlling aphid vectors with timely insecticide applications;
• implementing strict weed management to remove reservoir hosts;
• maintaining spatial isolation from perennial legume crops;
• using certified, virus-free seeds for planting.