Main symptoms

Significant differences in symptoms are observed depending on the species or variety infected, as well as depending on the strain of papaya ( ringspot virus Papaya ringspot virus , PRSV), which sometimes makes the diagnosis visual. difficult.

In melons ,  the symptoms of PRSV-W on foliage often begin with yellowing, a thinning of the veins subsequently evolving into a more or less deforming mosaic. The internodes are often shortened and the leaves take on a velvety appearance. PRSV-T strains cause necrotic symptoms in Charentais-type melons: necrotic lesions on leaves and necrotic stripes on stems which spread rapidly, leading to drying out and death of the plant. In other varietal types (Canary, for example) the symptoms of PRSV-T will be deforming mosaics like those caused by PRSV-W. PRSV-P is hardly ever found on Cucurbits under natural conditions.

Cucumber : Strong deforming mosaics are generally observed on foliage and sometimes on fruits, and general stunting of the plant.

Zucchini : PRSV most often causes strong symptoms of sometimes very deforming mosaic (filiformism, blisters). These symptoms can also be confused with those of Zucchini Yellow Mosaic Virus Viruses (ZYMV) or severe strains of Watermelon Mosaic (WMV). Fruit damage is also marked: blisters and mosaic which prevent any marketing.

Watermelon : Sometimes distorting mosaics appear on the foliage.