The normal argument cited in favour of GM crops is that the farmer would get a better yield due to its pest-resistance and herbicide-intolerance properties. The truth is there are various factors that influence the yield such as rains, soil quality etc. Nevertheless, in the case of the most cultivated GM crop soyabean there is enough evidence to show that the yields have suffered.
In India, excluding Gujarat, most states have had fluctuating yields with BT cotton. In the very first year of commercial Bt Cotton cultivation in India (2002-03), the largest survey on performance was done in the state of Andhra Pradesh, by the Department of Agriculture. It covered 53% of all Bt farmers in AP. In the survey 71% farmers reported low yield when compared to local hybrids. In the year 2004, the Andhra Pradesh government officially ordered Mahyco to pay compensation to the tune of four crores of rupees to Bt Cotton farmers who lost their crop, which the company refused to. In 2005 and 2006, there were widespread reports in the media about Bt Cotton being the cause of scores of farmers committing suicides after the crop failed. Usually GM seeds are patented so the farmer has to buy the seeds again from the company year after year.