Journal or Publishing Institution: Növényvédelmi Tudományos Napok
Study: https://web.archive.org/web/20180818141941/http://bdarvas.hu/download/pdf/GenetE.pdf
Author(s): Darvas, B., Lauber, É., Kincses, J., Vajdics, G., Juracsek, J., and Székács, A.
Article Type: Study
Record ID: 495
Abstract: Survivals of Plodia interpunctella larvae with MON 810 maize leaves contained feed, Cry1-resistant stocks – consist of 200 imagos – were collected in June, 2001. Larvae were feed on PIdb feed contained ~1.4 ppm (this slightly higher than the Cry1Ab toxin in fresh maize stem) truncated Bacillus thuringiensis toxin (Cry1Ab) plus maize leaves originated allelochemicals. Stocks were followed during 21 generations in 6 repetitions. In cases of 4th, 10th and 20th generations of Bt-resistant (Bt R) and Bt-sensitive (Bt S ) stocks mortality (5 repetitions), pupal mass (10 repetitions) and developmental time between egg laying and adult emergence (>100 repetitions) were evaluated. ELISA (EnviroLogix Inc, Portland, ME, USA) was used to quantity of Cry1Ab toxin DK-440 BTY (YIELDGARD) maize (MON 810 event). The dried and grinded leave of DK-440 BTY contained ~10 ppm Cry1Ab toxin. The rate of survivals higher during the 1st – 3rd generations based on progeny production of a female. Stabilization of the Cry1-resistance was a dynamic procedure. The breading reached the lower point at 6th generation and the Cry1Ab-resistant stock based on progenies of 24 imagos. This was caused by gene-combinations with disadvantages of population part was selected during 1st – 4th generations. Not only the truncated Cry1Ab toxin was the agent of selection, but different allelochemicals of maize leaves in which DIMBOA at the first half of June is well-known. Between 10th – 11th generations a deep population crash was also recognized. The larvae of 4th Bt R generation – where the selection pressure was 1.5 ppm – survived on 0.9 ppm Cry1Ab toxin, while they died when 1.7 ppm was applied. The developmental time of P. interpunctella was significantly longer consuming Cry1Ab toxin contained PIdb feed. The larvae of 4th generation of BtR was tolerant to Cry1Ab toxin. The larvae of 10th BtR generation – where the selection pressure was 1.5 ppm – a significant part survived on 1.6 ppm Cry1Ab toxin. Although the developmental time (embryonic + postembryonic times) of P. interpunctella was near the untreated control the pupal mass were half of them. The larvae of 10th generation of BtR was near resistant to Cry1Ab toxin. The larvae of 20th BtR generation – where the selection pressure was 1.5 ppm – no mortality was found on 1.6 ppm Cry1Ab toxin. Developmental time and pupal mass were similar than in case of isogenic control. In case of Bt-maize a relatively quick decrease in efficacy may be counted.
Keywords: Cry1-resistance; Plodia interpunctella; MON 810; DK-440 BTY; YieldGard; Dimboa
Citation: Darvas, B., Lauber, É., Kincses, J., Vajdics, G., Juracsek, J., and Székács, A., 2005. Bt-maize originated Cry1Ab toxin resistant Plodia interpunctella Abs. Növényvédelmi Tudományos Napok, 51(9).
