Major crops genetically modified for just two traits - herbicide tolerance and insect resistance – are ravaged by super weeds and secondary pests in the heartland of GMOs as farmers fight a losing battle with more of the same; a fundamental shift to organic farming practices may be the only salvation Dr. Mae-Wan Ho.
Please circulate widely, keeping all links unchanged, and submit to your government representatives demanding an end to GM crops and support for non-GM organic agriculture.
Two traits account for practically all the genetically modified (GM) crops grown in the world today: herbicide-tolerance (HT) due to glyphosate-insensitive form of the gene coding for the enzyme targeted by the herbicide, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), derived from soil bacterium Agrobacterium tumefaciens, and insect-resistance due to one or more toxin genes derived from the soil bacterium Bt (Bacillus thuringiensis). Commercial planting began around 1997 in the United States, the heartland of GM crops, and increased rapidly over the years.
By now, GM crops have taken over 85-91 percent of the area planted with the three major crops, soybean, corn and cotton in the US ] (see Table 1), which occupy nearly 171 million acres.
The ecological time-bomb that came with the GM crops has been ticking away, and is about to explode.
HT crops encouraged the use of herbicides, resulting in herbicide-resistant weeds that demand yet more herbicides. But the increasing use of deadly herbicide and herbicide mixtures has failed to stall the advance of the palmer super weed in HT crops. At the same time, secondary pests such as the tarnished plant bug, against which Bt toxin is powerless, became the single most damaging insect for US cotton.
Monster plants that can’t be killed.
It is the Day of the Triffids - not the genetically modified plants themselves as alluded to in John Wyndham’s novel - but “super weeds that can’t be killed” , created by the planting of genetically modified HT crops, as seen on ABC TV news.
The scene is set at harvest time in Arkansas October 2009. Grim-faced farmers and scientists speak from fields infested with giant pigweed plants that can withstand as much glyphosate herbicide as you can afford to douse on them. One farmer spent US$0.5 million in three months trying to clear the monster weeds in vain; they stop combine harvesters and break hand tools. Already, an estimated one million acres of soybean and cotton crops in Arkansas have become infested.
The palmer amaranth or palmer pigweed is the most dreaded weed. It can grow 7-8 feet tall, withstand withering heat and prolonged droughts, produce thousands of seeds and has a root system that drains nutrients away from crops. If left unchecked, it would take over a field in a year.
Meanwhile in North Carolina Perquimans County, farmer and extension worker Paul Smith has just found the offending weed in his field , and he too, will have to hire a migrant crew to remove the weed by hand.
The resistant weed is expected to move into neighbouring counties. It has already developed resistance to at least three other types of herbicides.
Herbicide-resistance in weeds is nothing new. Ten weed species in North Carolina and 189 weed species nationally have developed resistance to some herbicide.
A new herbicide is unlikely to come out, said Alan York, retired professor of agriculture from North Carolina State University and national weed expert.