Pamuk Yaprakbiti, Aphis gossypii Glover (Hemiptera: Aphididae)’nin farklı karpuz çeşitlerindeki popülasyon gelişimi

This study was carried out in Diyarbakir Plant Protection Research Station field in 2010-2011. Studies were replicated in the same field for two years, to determine population dynamics of alate and apterous forms of Aphis gossypii Glover (Hemiptera: Aphididae) on four different watermelon varieties (Crimson Sweet, Crimson Tide F1, Galactica and Surme). Population dynamics of A. gossypii were monitored weekly by yellow sticky traps and by sampling leaves of watermelon varieties. According to the results that obtained from this study the most density of apterous form of A. gossypii was monitored as 1.5-2 aphids/leave averagely in 2010, while this density has increased two folds as 3.5 aphids/leaves averagely in 2011. The most density of alate form of A. gossypii was monitored as 38 aphids/traps averagely in 2010, while this density has increased nearly ten folds as 380 aphids/traps averagely in 2011. Density of population dynamics of alate and apterous forms of A. gossypii in 2010 was lower than density of 2011. However there was numerical difference between varieties as to density of population dynamics of alate and apterous forms of A. gossypii , but there was no any statistical difference between varieties. Therefore it could be said that A. gossypii prefers all varieties and there is no variety preference of A. gossypii . Under climatic conditions of Diyarbakir province density of apterous forms of A. gossypii was the highest in June and July months in both years, while density of alate forms of A. gossypii was the highest in August and September months in both years. Aphids are present in the fields as colonies in May and June months and these colonies continue to till the middle of July, then by increasing of summer hot weather apterous aphids are converting into alate aphids from  July month to till September or October.