Saving papaya

Specific aphid identified as predominant virus vector
the papaya ring spot virus causes extensive damages to papaya, watermelon, squash, cucumber and pumpkin. Scientists suggest that the best way to reduce the loss is to cultivate these plants at a distance from each other and avoid their monoculture.
A study, published in the May issue of Phytopathology, has identified a kind of aphid (Aphis gossypii) as the predominant vector of the virus and suggested control measures. The researchers of Indian Institute of Horticulture in Bangalore, who carried out the study, say the vector can be controlled by growing papaya at least half a kilometre away from the other plants.
To identify the predominant vector, the researchers exposed three types of aphids to infected leaves and transferred them to 60-day-old papaya leaves. Then they analyzed the scale on infection.