The Relationship Between Population of Vector Aphids and Spreading of Viruses in Seed Potato: Case Study in Freidan Region, Isfahan

Aphids are important pests on potato, whose principal damage relates to spreading of viruses. Status of aphid vectors, viral diseases and the relationship between them were studied in an experimental field, in which virus-free tubers were cultivated for two years. Yellow sticky traps were used for trapping the aphids and in the laboratory, cumulative population densities were determined for two groups of green peach aphid (as dominant species) and other aphid species. The relationship between population density of aphids (in two groups of green peach aphid and other aphids), infection percentage of different viruses (PVY, PVS, PVM and PLRV) and the relationship between them were evaluated using the slope of linear regression and correlation coefficient. There was a very significant relationship between population density of green peach aphid and other aphids. The relationship of different viruses, except PLRV, with a population density of green peach aphid and other aphids were also significant. The results showed that in spite of the great importance of green peach aphid in transmitting viruses to seed potato, in Freidan region the viruses could also be transmitted by other aphids. Significant relationship between PVY and aphids could account more spreading of this virus in the seed potato fields in this region.