@article{article_48721, title={Investigations on biological activities of Bacillus thuringiensis against Colorado potato beetle [Leptinotarsa decemlineata (Say)] in the field and laboratory conditions}, journal={Plant Protection Bulletin}, volume={38}, year={1998}, author={Kedici, R. and Melan, K. and Bulut, H. and Ünal, G. and Has, A.}, keywords={Colorado potato beetle; Bacillus thuringiensis; biological activities; Patates böceği; Leptinotarsa decemlineata; biyolojik etkinlik}, abstract={Studies were carried out in order to determine the timing of the first application and the spray intervals of Bacillus thuringiensis var. tenebrionis (Novodor) and B. thuringiensis var . sandiego (M-ONE and M-TRAK) for the biological control of Colorado potato beetle [ Leptinotarsa decemlineata (Say)] in the field conditions in 1991-1993 in Ankara, Kazan. Effectiveness of these products were also determined on the larval stage of the pest in laboratory conditions. 1.20 ml/l and 0.60 ml/l dosages of Novodor gave the highest effects (59.4 and 53.1% respectively) against the first instar larvae after four days from the application in laboratory condition. The effects of all the products were lower on the other larval stages and no effect was found on the fourth stage. Initial spraying was started when the first stage larvae were dominant in the field. Spray intervals were 7-8 days in 1991 and 1993, and 14-18 days in 1992. All the products were tested in 1991 and 1992, but only Novodor were tested in 1993. Evaluation of the results were made according to the living larvae on the plant and defoliation by the pest in treated and untreated plots. In addition, yield was measured in 1993. The effects of M-ONE and M-TRAK were found lower than Novodor and Gusathion (Standard product) when they applied eight days intervals in 1991. Non of the products showed adequate efficacy when they applied 14-18 day intervals. Novodor tested at 200 and 500 ml/da was effective against the larvae of Colorado potato beetle in 1991 and 1993. It was concluded that, this product can be used with 10 days intervals against the larvae of the beetle by applying when the first stage larvae are dominant on the plants and three applications were necessary to control the first generation of the pest.}, number={3}, publisher={TARIM VE ORMAN BAKANLIĞI EĞİTİM VE YAYIN DAİRESİ BAŞKANLIĞI}