The phloem limited positive sense RNA virus[1] infects potatoes and other members of the family Solanaceae.

PLRV is one of the most important potato viruses worldwide but particularly devastating in countries with limited resources and management.

One estimate suggests that PLRV is responsible for an annual global yield loss of 20 million tons.

The fact that only specific cells within the tuber are affected by this problem while others remain normal causes the characteristic net symptom.

There is a strong resemblance between PLRV net necrosis and another tuber defect known as stem end discoloration (SED).

Very small percentages of PLRV in seed potatoes do not normally pose any risk for the commercial producer.

However, even very small percentages of virus can be a problem if green peach aphids appear very early and in abundance.

In years that are very favorable for insects, like the 1996 season was, the aphid population can become so large that even a very low percentage of PLRV infected seed could result in sufficient spread to cause a problem, because as the aphid population increases, so does the probability that they will encounter an infected plant.

Large tubers that show the typical net necrosis symptom may well be the result of current season infection.

Husk tomato, Physalis floridana symptoms include chlorosis, rolling of the leaves and stunting.

[6] Because of the wide array of symptoms that occur in different hosts, diagnosis of PLRV must be done based on the infected species.

[8] This process takes several hours, after which time the aphid will continue to transmit the virus for its remaining life.

In temperate regions, the green peach aphid is able to persist through the winter by laying eggs in woody species of the genus Prunus.

During this time the green peach aphid can transmit PLRV present in weeds of the family Solanaceae to potatoes and other crops.

Winged aphids can be carried several hundred kilometers by wind currents, allowing for widespread infection.

Warm humid conditions are preferred, but aphids can thrive in a number of climates as long as it is not too hot and dry, as their soft bodies make them prone to desiccation.

In the tropics, aphids persist year round but the efficiency of PLRV transmission is reduced at temperatures above 26 degrees Celsius.

Plantings from infected tubers will not yield acceptable market quality potatoes and can cause a significant loss.

[17] One study found that ethyl-methyl parathion pesticides are less effective at controlling the green peach aphid at lower temperatures.