Water Deficit Has no Effect on Efficacy of Bt on GM Cotton

There has been a concern that water deficit may reduce the efficacy of Bt in biotech cotton. However, an international group of experts concluded otherwise. The researchers found out that a moderate water deficit does not affect the effectiveness of Bt to the African cotton bollworm.

The group of C.M. Martens evaluated the growth of Bt cotton plants under moderate water deficit.  They reported that the leaves from young plants exposed for 30 days to moderate water deficit had both higher Bt toxin concentrations and were more effective against larvae than leaves, flowers or bolls from mature flowering plants exposed to 60 days. The researchers also observed that while overall, water deficit decreased Bt concentrations in leaves, flowers and bolls of biotech cotton, this had no effect on efficacy against first-instar cotton bollworm larvae.

The paper published in the Annals of Applied Biology is accessible to journal subscribers at http://www.blackwell-synergy.com/doi/abs/10.1111/j.1744-7348.2007.00214.x