Cotton farmers face Resistant Pink bollworm in Bt cotton

Pink bollworm (Pectinophora gossypiella) was a key pest of cotton prior to introduction of GM cotton. This pest infests only flowers and bolls. It feeds inside the bolls and seeds inside. As GM cotton expresses less toxin in floral and bolls, the larvae ingest sublethal doses. This pest has acquired resistance to Bt cotton. As early as 2004, we started work on efficacy of Bt toxins against Pink bollworm larvae. We found resistance development in the Amreli population of pink bollworm to Bt toxin, Cry1Ac in 2009 and published our studies in early 2011. A year before, Monsanto in its press release extensively reported up on the pink bollworm resistance to Bt cotton. However, the official establishments did not take a serious note of that. On the contrary, they said that Monsanto wants to promote BGII (that produces two-toxins Cry1Ac and Cry2Ab) and hence, this is a strategy to malign Bt cotton that produces only one-toxin Cry1Ac. Associated with this is a fact that native seed companies were able to develop a GM cotton with only one toxin of their own. Accepting the claim of Monsanto would have meant abondoning the native companies and Govt own institutions that were developing one-toxin Bt cotton technology.
Pink bollworm in the meanwhile enjoyed its freedom as Bt cotton cultivation increased more over the years. In 2014 and 2015, resistance in pink bollworm to Bt cotton reached a level that showed visible decline in cotton productivity. I visited Bt cotton fields in Bhavnagar in Saurashtra to know more of this problem. The damage ranged from 10 -30%.  2016 was relatively fine year, with normal well distributed rain-fall, but reduced cotton area; as farmers had diverted area towards pulses. Pulse prices had skyrocketed earlier and the farmers wanted to forget bad years of Bt cotton due to pink bollworm and whitefly.
In 2017, pink bollworm resurfaced, resurrected far and wide in Central and South India. Maharashtra made the news as pink bollworm resistance showed perceptible loss of cotton yields. On all India basis, the production that was foretold at the beginning of season was about 40 million bales. At the end, it turned out to be ca. 34 million bales. Farmers had gone back to Bt cotton cultivation, after realizing poor prices of their pulse production.
Maharashtra also made a news in 2017. In Aug and Sept, as many as 40 farmers and farm labours died of pesticide poisoning in cotton fields.
Pink bollworm has evolved resistance to both toxins, Cry1Ac and Cry2Ab and resistance is adversely affected Bt cotton.
Now, all stakeholders like Govt, farmers and Ag scientists are involved in strategies for management of pink bollworm resistance.
Hope 2018 as predicted to be normal year for rains brings back bountiful of harvests and increases farmers income significantly with MSP, price difference compensation mechanism, insurance scheme, and other support systems.


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