Begomovirus macroptilaurei

This virus primarily infects plants of the Fabaceae family, particularly tropical species such as Macroptilium lathyroides.

Like other members of this genus, this virus is generally not transmitted mechanically or through seeds in most studied cases, requiring a specific insect vector.

The vector of the virus is the tobacco whitefly (Bemisia tabaci), which acquires the pathogen while feeding on an infected plant.

The virus circulates within the insect in a persistent-circulative manner, allowing the whitefly to remain infectious for the duration of its life.

The primary visual signs of infection are chlorotic spots that eventually merge to form a mosaic pattern on the plant leaves.

Significant deformation of the leaf blade is often observed, accompanied by downward or upward curling of the leaf margins.

The growth of the infected plant is significantly stunted, with shortened internodes leading to a bushy or dwarf appearance.

In the generative phase, floral malformation is noted, along with a decrease in the quantity and quality of pod development.

• Vein clearing (yellowing of leaf veins);
• General chlorosis of the aerial parts;
• Premature leaf drop in cases of severe infection.

The spread of the virus depends directly on the population of the vector, the whitefly, whose activity increases in hot and dry climates.

High air temperatures are considered optimal for epizootic development, as they favor the rapid reproduction of insect vectors.

The virus spreads easily in agroecosystems where crop rotation is neglected and reservoir weeds capable of sustaining the virus during the off-season are present.

Migration of whiteflies from adjacent infected fields or wild legume species serves as the primary source of initial infection.

Lack of spatial isolation between crops of different ages also triggers the rapid accumulation of inoculum in the field.

The harmfulness of Begomovirus macroptilaurei manifests in significant losses of legume crop production.

Infected plants yield fewer seeds, and their nutritional value and germination rates can be significantly reduced due to disrupted physiological processes.

Severe infection during early growth stages often leads to complete loss of individual plant productivity and thinning of the crop stand.

Viral infections of this type are extremely difficult to treat once established, making them a major threat to commercial agriculture.

In the long term, the presence of this virus in a region limits the viability of cultivating susceptible legume varieties.

The main protection strategy is the control of the vector, the whitefly, using systemic insecticides during the early stages of plant development.

Strict spatial isolation of new crops from old legume plantings, which may serve as a virus source, must be maintained.

An important preventive measure is regular weed control, as weeds serve as reservoirs for both the virus and its insect vector.

The use of healthy, certified planting material is recommended, even if seed transmission is not the primary route for this specific species.

Applying agricultural practices such as using non-woven row covers in greenhouses or observing optimal planting dates helps reduce the risk of infection.