Investigations on the effects of different insecticide application methods used against harmful insects on beneficial insects in early growing stage of cotton

ABSTRACTMSc THESISINVESTIGATIONS ON THE EFFECTS OF DIFFERENT INSECTICIDEAPPLICATION METHODS USED AGAINST HARMFUL INSECTS ONBENEFICIAL INSECTS IN EARLY GROWING STAGE OF COTTONMahmut GÜNEŞDEPARTMENT OF PLANT PROTECTIONINSTITUTE OF NATUREL AND APPLIED SCIENCESUNIVERSITY OF ÇUKUROVASupervisior: Assist. Prof. Dr. Ekrem ATAKANYear: 2005, Pages: 52Jury: Assoc. Prof. Dr. Cengiz KAZAKAssist. Prof. Dr. Erdal SERTKAYAThis study was carried out in the field of Cukurova Agricultural Research Institute(Adana-Doğankent) in 2005. In this study, the effects of seed dressing method(thiamethoxam), whole application method (diazinon) and partial application method(dimethoate) used against cotton aphid (Aphis gossypii Glover), thrips (Thrips tabacilindeman), red spider mite (Tetranychus cinnabarinus Boisd.) and cotton leafhoppers(Asymmetresca decedens (Paoli) and Empoasca decipiens Paoli) in the early growing stageof cotton plants on coccinellid predators (Coccinella septempunctata L., C. undecimpunctataL., Stethorus gilvifrons (Muls.), and Scymnus spp.) hemipterian predators (Deraeocorispallens Reut. Orius spp. and Geocoris spp.) chrysopid predator (Chrysoperla carnea(Stephens), thysanopterian predators (Scolothrips longicornis Pries. and Aeolothrips spp.)cecidomyiid predator (Aphidioletes aphidimyza Rondoni) and aphid parasite (Aphidius sp.)were investigated.In seed dressing method, populations densities of cotton aphid and red spider mitedecreased, leafhoppers and thrips populations were not affected so much. In wholeapplication and partial application methods, while cotton aphid was affected, leafhoppers andthrips were affected partly and red spider mite increased sometime after spraying.In insecticide treated plots of all application methods, population densities ofpredator insects were lower than untreated plots. There was no statically differences betweeninsecticide application methods in term of population densities of beneficial insects, but, itwas a little higher in seed dressing plots than the other two methods. Populations ofcoccinellid, hemipterian, chrysopid and thysanopterian predators did not disappearcompletely in treated plots; some adults migrated to unthreated plots in whole and partialapplication methods. This case was seen obviously in partial application method.Key Words : Cotton, Seed Dressing Method, Whole Application Method, PartialApplication Method, Beneficial InsectsII