In Pakistan, experts believe that low level of Bt toxins in GM cotton crops have immunised the pests instead of killing them
Bollworms develop resistance against Bt cotton crop
Dawn.com, 14 Jul 2014
Farmers and agriculture scientists are alarmed by the destructive attack of bollworms this year that seem to have developed resistance against the genetically-modified (GM) cotton crop.
The surprise comes especially when different species of bollworms, such as American, Pink and Spotted bollworm, were supposed to be eradicated after feasting on the GM Bt cotton crop. Instead, these destructive pests have attacked a major cotton growing belt in Southern Punjab, this year.
Farmers fear instead of being eliminated, the bollworms developed resistance due to insufficient toxin levels in Bt cotton crop.
If not controlled, the pests’ attack on cotton crop will most likely damage the quality of fibre and the cotton seed, resulting in a decline in the yield this year.
“All Bt varieties of cotton have failed to kill bollworms and live up to their agricultural success stories. We have found four separate patches in our fields where Army bollworm and mealy bug have attacked the crop,” said Chaudhry Gohar Ali, who grows cotton in Vehari near Multan.
The 73-year-old cotton grower complained that most farmers felt helpless and concerned government offices were urging the farmers to continuously spray pesticides.
Despite availability of Bt varieties Bollgard-II (BG-2) and Roundup Ready Flex (RRF) cotton in the markets of Southern Punjab and Sindh, it was surprising that the farmers were reporting pest development in the cotton fields.
A cotton grower from Shahdadpur in Sindh, Muhammad Bux, is equally concerned about his crop spread on 100 acres.
“I am surprised how these pests have survived after eating the Bt cotton crop. Pests should be dying because of the high doses of toxins in Bt cotton plant and not developing resistance, which seems to be the case here,” said Bux, who was also resorting to more than usual dose of pesticide. He explained that since the last few years, the Gulabi Sundi (Pink Bollworm) has been causing devastation in three districts of Sindh every year and farmers have to spray pesticides to save their GM cotton crop.
With prices of pesticides ranging between Rs600 to Rs700 per litre, the costs of production have also gone higher for the farmers, without any relief from government. The usage of pesticides increased after Bt was introduced in Pakistan, as the cotton production had been reducing.
According to experts in Pakistan Agriculture Research Council (PARC), pests have possibly started developing a resistance against Bt crops, since they were introduced in 2004-05. The genetically modified cotton seeds contain insufficient dose of toxins that killed pests and were also of poor quality.
“The government has spent an estimated Rs985 million, besides foreign aid, in this regard in the name of research and development of biotechnology. Instead of developing indigenous modified seeds, researchers and scientists ended up copying technology from multinational seed-producing companies and started selling them in the markets to local farmers,” said an agriculture expert in PARC.
When GM crops were officially introduced in Pakistan in 2010, the move was resisted as some stakeholders believed that bollworms were less disastrous than leaf curl virus and mealy bug, against which Bt is completely ineffective.
The senior official also added that there was no national pest management programme to educate farmers regarding pests and to monitor the development of resistance.
Documents by Punjab Pest Alert Department, available with Dawn, show how the threat of these bollworms had always been as low as one to two per cent in Punjab, where 80 to 90 per cent of the country’s cotton is produced amounting to about 10 million bales annually.
Pakistan Atomic Energy Commission (PAEC) Director Agriculture and Biotech Dr Nayyer Iqbal did not seem surprised by the attack of bollworms on cotton crop.
“Resistance in pests has been developing because of low toxin levels. Some Bt seed variety have absolutely no toxin doses at all, making the crop vulnerable to pest infestation,” said Dr Iqbal, explaining in not so many words how a host of problems associated with GM seed in Pakistan had caused the new technology to almost fail.
“The idea of introducing genetically modified seeds in Pakistan was to minimise pesticide usage and reduce the costs of inputs, apart from keeping the environment clean,” said Dr Iqbal, who explained how several uncertified and unregulated varieties of seeds were being sold in the market without any government departments regulating the quality of seeds.
“It is a little early to elaborate on how widespread the attack is. But it will definitely impact the cotton yield,” Dr Iqbal said. Sarwar Rahi, who is a technical manager for a private pesticides and seed importing company, recently completed a field survey in Multan and confirmed the attacks of bollworms in Punjab. “The farmers are using substandard seed that is also low in toxins available in the market. It is being presumed that pests are developing resistance due to low toxin levels in Bt seed varieties,” Mr Rahi said.