YIELD LOSSES DUE TO DIURAPHIS NOXIA (KURD.) (HOMOPTERA: APHIDIDAE) DAMAGE ON CANARYGRASS IN KONYA PROVINCE OF TURKEY

Abstract

Russian wheat aphid, Diuraphis noxia (Kurdjumov), although is an occasional pest for wheat and barley in Konya province of Turkey, it causes severe damage on canarygrass, Phalaris canariensis L. every year. To determine yield losses caused by D. noxia on this plant, trials were arranged as factorial experimental design with 14 replications for two years. The 14 canarygrass plots were weekly sprayed by oxydemeton-methyl at 200 cc /100 lt water and other 14 plots were left for natural aphid colonization. Aphid counting was done weekly during vegetation period. All yield components measured were significantly affected by D. noxia damage. The rates of reduction in these components were as follows: 81,7 % in grain yield, 57,1 % in panicula number per square meter, 55,43 % in grain weight per ten panicula, 43,97 % in grain number in panicula, 36,44 % in plant height, 26,95 % in 1000 kernel weight, and 11,03 % in panicula length. Only potassium level of the determined macronutrients (nitrogen, phosphorus and potassium) was significantly higher in infested plots than sprayed plots. As a result, canarygrass cultivation is not recommended for Konya province due to the economic losses attributable to D. noxia and possible threat to wheat cultivation.