Acknowledging that the economic advantage of Bt cotton is related to the varying level of pest infestation, all countries growing Bt cotton have reported economic gains; these are documented in detail and referenced in the country case studies on pages 85 to 136 in this publication. Based on surveys of commercial Bt cotton and extensive replicated multi-locational trials over several years, the largest economic gains per hectare have accrued to China. The economic gain per hectare for commercial Bt cotton in China has been up to $550 per hectare (Pray et al 2002). Significant and consistent economic gains have been recorded in large scale national field trials in India, ranging from $75 to $200 or more per hectare, with most of the estimates on the higher end of the range. Mexico can have substantial but variable gains. Extensive field trials and surveys in the US have reported average gains per hectare of $50 to $80 and substantially more in some cases. Economic gains from Bt cotton in South Africa are up to $50 per hectare with those in Australia and Argentina ranging from $25 to $50 per hectare.

Global experiences with Bt cotton have clearly demonstrated the economic advantage gained from using this technology. In general the overall economic benefit of Bt cotton results from yield increases, and decreases in insect control costs, which are partially offset by the higher price of Bt cotton seed, including the technology fee where it is applicable. Taking all these factors into account, the highest national economic returns in 2001 accrued to China and the US, which grew 35% and 60% of world Bt cotton respectively. Australia, South Africa, Argentina, Mexico and Indonesia also benefited and are expected to be joined by India and Colombia in 2002. A discussion of the salient issues related to the economic gains from Bt cotton in the respective countries follows.