بررسی و شناسایی گونه غالب شته های خسارت زا درمزارع غلات استان آذربایجان غربی

In this survey that was executed for 2 years in west Azarbaijan province,diversity of aphid's damage and percent of contamination were examined in wheat and barley in fields.In each region of Khoy,Chaldoran & Miandoab three fields were selected randomly and aphid's species and also percent infection were determined by using quadrate(0.5*0.5m2) and counting stems & aphids.Collected species of aphids were identified and their percentage of infection was determined by the ratio of infected stems to the total number of stems. Results showed Sitobion avenae F. species was determined as the predominant species in different regions of this province.The Maximum and minimum percent of infection were observed in Chaldoran fields and in Khoy and Miandoab,respectively. Infections in Chaldoran had high variance, and result showed that this region is one of the susceptible centers for developing of S.avenae.
S.avenae was as a predominant species of aphid that have very extensive adaptation on different regions from Chaldoran to Miandoab.The species Metopolophium dirhodum W. dispersed in the coldest regions at north of province, and Schizaphis graminum presented in warmer regions specially at Miandoab.
In cold condition of the north height altitudes M.dirhodum and in warmer condition S.graminum species had higher adaptability and distribution but population density of these species have not been as S.avenae density.