thrips (thysanoptera) 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.