Cucurbit aphid-borne yellows virus

Cucurbit aphid-borne yellows virus (CABYV) is a significant plant pathogen belonging to the genus Polerovirus within the family Solemoviridae. It primarily affects plants in the Cucurbitaceae family, including cucumber, melon, zucchini, and squash, posing a major challenge to horticultural productivity worldwide.

The disease manifests through distinct foliar symptoms, typically characterized by interveinal chlorosis (yellowing) of older leaves, which progresses upward. As the infection advances, the leaves thicken and become brittle, significantly impairing photosynthetic efficiency and leading to fruit malformation and stunted plant growth.

Transmission occurs in a persistent, circulative manner primarily via aphid vectors, most notably the cotton aphid (Aphis gossypii). Once the aphid ingests the virus by feeding on an infected plant, it carries the pathogen within its system, allowing for the transmission to healthy crops throughout its lifespan after an acquisition and latency period.

Epidemiological spread is highly dependent on environmental factors that influence aphid populations, such as warm, dry weather. These conditions promote rapid colonization of fields by aphids. Additionally, the virus survives in various perennial weed species, which serve as crucial reservoirs for reinfection in subsequent growing seasons.

Managing CABYV requires an Integrated Pest Management (IPM) approach. Key strategies include:

• Rigorous monitoring and timely application of insecticides to control aphid vector populations.
• Selecting and planting resistant or tolerant cucurbit cultivars.
• Implementing strict weed control measures to eliminate alternate virus hosts.
• Using reflective mulches to deter aphid landing and colonization on young plants.