Efficacy and integration of different control methods against corn stem borers [Ostrinia nubilalis Hübner (Lep: Crambidae), Sesamia nonagrioides Lefebvre (Lep: Noctuidae)] in Çukurova

Corn stem borers [Ostrinia nubilalis Hübner (Lepidoptera: Crambidae), Sesamia nonagrioides Lefebvre(Lepidoptera: Noctuidae)] are the key pests of second crop maize production in East Mediterranean Region of Turkey. In this study, efficacy of chemical (C), biotechnical (BTC) and integrated pest management (IPM) practices were studied for control of stem borers, between the years of 2011-2013. Also the side effects of some insecticides registered in maize on an egg peresitoid, Trichogramma evanescens Westwood (Hymenoptera: Thricogrammatidae) were tested. As a result, in IPM, BTC and C plots, egg numbers of S. nonagrioides were reduced ranging between % 36.5-73, % 38-69 and %27.2-72.8 respectively. It was found out that mating disruption pheromones caused a reduction up to 73 % in S. nonagrioides egg numbers. T. evanescens releases as an integrated control approach, resulted in 87.33-92.13 % parasitism on O. nubilalis egg masses and reduced the larval populations 72 %. Chemical control, if applied correctly, wass found to be the most effective control method for both stem borers. Natural parasitism of S. nonagrioides eggs by Telenomus busseolae Gahan (Hymenoptera: Scelinoidae) reached up to 80 % at the end of the growing season. Chlorpyrifos ethyl based insecticides caused a 100 % mortality on all life stages of T. evanescens. Lambda cyhalothrin and deltamethrin based insecticides, both of which are pyrethroids, slightly harmful (Class 2) on preimaginal stages and moderately harmful (Class 3) on adults. Novaluron and Indoxacarb were harrmless (Class 1) to preimaginal stages and slightly harmful to the adults (Class 2) Chlorantraniliprole was harmless (Class 1) on all steges of T. evanescens. As a result, C was found out to be the most effective control method against corn borers. The studies on integrated pest management including selective insecticides and other tactics should be continued.