Field monitoring of Helicoverpa armigera (Lepidoptera: Noctuidae) Cry1Ac insecticidal protein resistance in China (2005–2017)

• Published in: Pest management science Vol. 75; no. 3; pp. 753 - 759
• Main Authors: Dandan, Zhang, Yutao, Xiao, Wenbo, Chen, Yanhui, Lu, Kongming, Wu
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.03.2019; Wiley Subscription Services, Inc
• Subjects: Animals; Bacterial Proteins; China; Commercialization; Cotton; cry1Ac; Cry1Ac toxin; Diagnostic systems; Endotoxins; field populations; Gossypium - genetics; Gossypium - parasitology; Helicoverpa armigera; Hemolysin Proteins; Inhibitory Concentration 50; Insecticide resistance; Insecticide Resistance - genetics; Larva - growth & development; Larval development; Monitoring; Moths - genetics; Moths - growth & development; Organic chemistry; Plants, Genetically Modified; Populations; Proteins; resistance monitoring; China; field populations; Helicoverpa armigera; cry1Ac; resistance monitoring
• ISSN: 1526-498X; 1526-4998
• DOI: 10.1002/ps.5175

BACKGROUND Bt cotton expressing Cry1Ac can efficiently control Helicoverpa armigera, but field‐evolved Bt resistance reduces its efficacy. Susceptibility of H. armigera field populations to Cry1Ac protein has been monitored since Bt cotton was commercialized in 1997 in China. Here we report the results of our continued monitoring from 2005 to 2017 to provide important guidelines for sustainably growing cotton. RESULTS From 13 provinces and regions, 221 populations were sampled and measured. IC50 values (concentration producing 50% inhibition of larval development to third instar) among different strains ranged from 0.004 to 0.212 µg mL−1, the percentage survival at a diagnostic concentration (IC99, 1.0 µg mL−1) (SUR) ranged from 0% to 22.2%, and the percentage of field populations yielding survivors at diagnostic concentration (PSD) increased from 0 in 2006 and 2007 to 80% in 2015. CONCLUSIONS Compared to resistance level from 1998 to 2004 and the geographic baseline in different places of China in 1997, Bt resistance of H. armigera field populations to Cry1Ac protein has increased significantly, but failure of Bt cotton has not yet been detected. © 2018 Society of Chemical Industry Susceptibility of Helicoverpa armigera field populations to CrylAc has been monitored since 1997 in China. Here we report our results from 2005 to 2017, which may provide guidelines for growing Bt cotton.