Cotton Bollworm (IMAGE) University of Arizona Caption The caterpillar pest Helicoverpa zea (also known as cotton bollworm and corn earworm) has evolved resistance to four Bt proteins produced by biotech crops. Credit Alex Yelich/University of Arizona Usage Restrictions This visual may only be used in conjunction of reporting/posting of this news release. Credit must be stated as indicated. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.