Analysis of resistance to Cry1Ac in field-collected pink bollworm, Pectinophora gossypiella (Lepidoptera:Gelechiidae), populations

• Published in: GM crops & food Vol. 5; no. 4; pp. 280 - 286
• Main Authors: Ojha, Abhishek, Sree, K Sowjanya, Sachdev, Bindiya, Rashmi, MA, Ravi, KC, Suresh, PJ, Mohan, Komarlingam S, Bhatnagar, Raj K
• Format: Journal Article
• Language: English
• Published: United States Taylor & Francis 2014
• Subjects: Animals; Bacterial Proteins - metabolism; Bollgard; brush border membrane vesicle; Bt cotton; Cry1Ac-resistance; Endotoxins - metabolism; Gossypium - genetics; Gossypium - parasitology; Hemolysin Proteins - metabolism; India; Insect Proteins - metabolism; Insecticide Resistance; Insecticides - metabolism; Larva - physiology; Moths - growth & development; Moths - metabolism; pink bollworm; Plants, Genetically Modified; receptor binding; Research Paper; India; brush border membrane vesicle, Bt cotton; MRC, Monsanto Research Center; NKJ, Nandurbar-Khargaon-Jalgaon; IRM, insect resistance management; BBMV, brush border membrane vesicle; PBW, pink bollworm; Bollgard; Cry1Ac-resistance; PBS, phosphate buffered saline; receptor binding; pink bollworm; Bt, Bacillus thuringiensis
• ISSN: 2164-5698; 2164-5701
• DOI: 10.4161/21645698.2014.947800

High survivorship of pink bollworrm, Pectinophora gossypiella in bolls of Bollgard® cotton hybrids and resistance to Cry1Ac protein, expressed in Bollgard cotton were reported in field-populations collected from the state of Gujarat (western India) in 2010. We have found Cry1Ac-resistance in pink bollworm populations sourced from Bollgard and non-Bt cotton fields in the adjoining states of Maharashtra and Madhya Pradesh in Central India. Further, we observed reduced binding of labeled Cry1Ac protein to receptors localized on the brush-border membrane of pink bollworm larval strains with high tolerance to Cry1Ac. These strains were sourced from Bollgard and conventional cotton fields. A pooled Cry1Ac-resistant strain, further selected on Cry1Ac diet also showed significantly reduced binding to Cry1Ac protein. The reduced binding of Cry1Ac to receptors could be an underlying mechanism for the observed resistance in pink bollworm populations feeding on Bollgard hybrids.