Thirips (Thysanoptora) Species associated with wheat and barley in Golestan province, Iran

Fields of winter wheat and barley were sampled during two years (November to June 1996-1998) in Golestan province to determine the occurrence, frequency and distribution of thrips species. A total of 32 species belonging to 3 families and 16 genera were found. Haplothrips tritici (Kurdjumov) was the dominant species accounting for 70.2% and 55.7% of identified individuals in wheat and barley, respectively. Sitothrips arabicus Priesner was the second most abundant species, comprising 13.5% and 20.1% in wheat and barley, respectively. Regression analysis showed a non-linear relation (y = 42.65 + 0.33x – 0.0002x2) between altitude (x) and population density of H. tritici (y) on wheat. Locality and date of collection, host(s) and distribution data for each species are given.