Genetically modified (GM) plants are grown on more than 67 million hectares in 18 countries worldwide. A major trait used in GM crops is plant resistance to insects; this trait is based on several Bt proteins. The benefits accruing to farmers growing Bt crops are substantial across a number of geographies and economic strata, especially in developing countries. These benefits include increased crop yields, reduced pesticide use, less environmental damage, less fungal contamination, and reduced labor. Constraints to broader use of GM traits in a wider variety of food crops and in a larger range of countries include the lack of regulatory bodies in some countries, access to credit, support institutions such as extension or seed company technical advisors, and public acceptance, especially as it relates to international trade.
Key words: Africa, Bt, Bacillus thuringiensis, China, cotton, developing world, GM, India, insect, pest, maize, Philippines, potato.