Title: Tanzania: Superweeds caused by GMO are super problems
[Tanzania Daily News 20 May 2012 by Anne Outwater] -- An important claim made by the supporters of genetically modified plants is that they will decrease need for chemical pesticides and herbicides. This is a great dream because these chemicals have tremendously negative impacts on ecosystems and humans. But this dream has turned into a nightmare. In India, a survey conducted by Navdanya in Vidharbha region showed that pesticide use has increased 13 times since Bt cotton was introduced. (Bt stands for Bacillus thuringiensis, a bacterium usually found in the soil; the toxic gene within it has now been inserted into crop plants by corporate scientists so that the plants themselves continuously produce the toxin.)
In India, Bt cotton sold under the trade name "Bollgard" was supposed to control the Bollworm caterpillar. Today, the Bollworm has become resistant to Bt cotton and now Monsanto is selling Bollgard II with two additional toxic genes in it. In spite of all that, a study published in the Review of Agrarian Studies showed that small farmers in India had a higher expenditure on chemical pesticides for Bt cotton than for other varieties (Swaminathan & Rawal, 2011).
There are estimates that use of Bt corn and cotton in the United States have reduced insecticide use by 125 million pounds. However, more insecticides than that were directly excreted by the plant itself through Bt Cry proteins. For example, each acre planted with Bt corn for corn rootworm and other soil borne insects can decrease the use of insecticide by about 0.21 pounds per acre.
However, the genetically modified plants themselves introduce 0.5 to 2.5 pounds of Bt Cry proteins per acre. Making a plant herbicide resistant, means that herbicides can be applied to a field and everything will die except for the GM plant. This practice is leading to dramatic increases in the uses of these poisons. Most of these genetically modified crops were developed in the United States and the highest production is there.
In the United States (where most of these genetically modified crops were developed and produced), it seemed at first that there was a reduction in the amount of herbicides applied to GM crops. For the first four years of commercial use of genetically engineered crops, herbicide use decreased by about 2% (Benbrook, 2012). However since then, rates of glyphosate (in the herbicide roundup) use on corn, soybeans, and cotton have increased more than 10 per cent per year.
It is estimated that GM crops in the United States have increased the use of herbicides by 240 million kilos more than what would have likely been used in the absence of genetic engineering. United States Geological Service scientists collected weekly air particle and rain samples during two growing seasons in two states that allow genetically engineered herbicide tolerant crops, (Feng-Chin, Simcik, Capel, 2011).
Glyphosate, which is linked to spontaneous abortions in lifestock, birth defects in human beings, insect resistance and weed resistance was found in 60-100% of rain and air samples tested. Virtually every stream, river and reservoir in heavily farmed areas was found to be contaminated with glyphosate. Moreover, the rise of glyphosateresistant weeds has made it necessary to combat these weeds by employing other herbicides.
This trend is confirmed by 2010 United States Department of Agriculture pesticide data, which shows skyrocketing glyphosate use, accompanied by constant or increasing rates of use for other, even more toxic, herbicides. In the United States, seeds genetically modified to resist herbicides have produced weeds resistant to glyphosate (Round Up).
Current surveys indicate that almost 20 percent of US producers have found glyphosate resistant (Roundup Resistant) weeds on their farms. As a result of this weed resistance, farmers are being forced to use more herbicides to combat weeds.
Approximately 15 million acres are now overtaken by Roundup resistant "superweeds", and, in an attempt to stop the spread of these weeds, Monsanto has started offering farmers a "rebate" of up to six US dollars per acre for purchasing and using other, more lethal herbicides.
These rebates offset approximately a quarter or a third of the cost of purchasing the other herbicides. As Bill Freese of the Center for Food Safety in Washington DC says "The biotech industry is taking us into a more pesticide dependent agriculture, and we need to be going in the opposite direction."
Article: WeedsNews3331 (permalink) Categories: :WeedsNews:herbicide resistance, :WeedsNews:genetics Date: 24 May 2012; 11:07:16 AM AEST