Sir

Immediately after publication of your News story “Transgenic cotton gets mothballed after protests” (Nature 418, 716; 2002), the agriculture minister of Karnataka retracted the state's ban on Bt cotton seeds on the grounds that only the central government can make such a decision (The Hindu, 16 August 2002). The state can advise central government on whether to impose a ban, if evidence can be shown of adverse impact on animal (including human) and plant health.

In this case, the state minister banned Bt seeds in the light of concerns about their environmental impact after he had been briefed by protesters citing a Greenpeace report about Bt cotton in China. However, the minister had not at that time been informed about criticisms of this report by two Chinese scientists, who called it “garbled and biased” (see the Biosafety Information Network and Advisory Service, http://binas.unido.org/binas), hence his swift retraction of the ban.

This controversy represents a constitutional challenge, as the Indian constitution makes the environment the responsibility of central government and agriculture that of individual states. The state of Karnataka can regulate and restrict any executive and legislative process initiated by central government in the domain of agriculture. However, the introduction, development and commercialization of genetically modified plants are governed by centrally enacted environment laws in India.

This type of confusion can only hamper the advance of biotechnology and the development of agriculture, and needs to be resolved by bringing agriculture under the constitution's Concurrent list. This would eliminate the possibility of disputes because, in cases of disagreement about items on that list, central government legislation prevails over that of the states.