Aphid plant virus

Aphids will remain infective able to vector a virus with a persistent virus for at least a week and potentially throughout their life. A good insect management program can be very helpful in dealing with persistent virus diseases. Aphids pick up nonpersistent viruses by merely probing exploring an infected leaf. This happens rapidly--within seconds or minutes. A dormant period is not required and the aphid can immediately transmit the virus by probing another plant.

Aphids remain infective with nonpersistent viruses for a short time minutes. Systemic materials are generally the most effective insecticides available for aphid control. Systemic insecticides are taken into the plant and become present in the plant juices. Aphids feed by sucking juices from the plant, and when they do so they also ingest some of the insecticide. However, when just probing a leaf an aphid is not feeding and does not ingest plant juices or insecticide.

In fact, the presence of an insecticide may actually stimulate probing and cause aphids to move from plant to plant in an effort to fine a suitable feeding site.

This can increase the spread of nonpersistent viruses. For this reason nonpersistent viruses are very difficult to manage. There are no pesticides that kill viruses and, as explained above, they may actually make matters worse.

Eradication of perennial weeds around fields can reduce the source of the virus. The green peach aphid is not the only aphid that transmits viruses, but it is important because it is a universal vector. Porras explained that in the absence of viruses, the aphid species Rhopalosiphum padi typically is the first to invade wheat plants, while Rhopalosiphum maidis arrives later. If the opposite occurs — R. However, when R. The better the aphids do, the higher the probability that they will spread the virus to the host plant and to other aphids.

Porras and her colleagues designed a set of field and laboratory experiments in which they manipulated the presence of virus strains within aphids, along with the order of aphid species arrival to wheat plants. They recorded the time it took for the aphids to start feeding, the duration of feeding and the reproductive health of the aphids. Most viruses, and many proteins from animals, have carbohydrate or carbohydrate-binding sites. Lectins vary in their specificity, of which some are able to bind to viral glycoproteins.

To assess the potential competition between lectins and viral particles in virus transmission by aphids, this study examined how feeding plant lectins to aphids affects the transmission efficiency of viruses.

Sitobion avenae F, Homoptera: Aphididae aphids fed with Pisum sativum lectin PSL transmitted Barley yellow dwarf virus with significantly lower efficiency four-fold ratio.