A study of GMO cotton varieties shows they disrupt an important beneficial soil fungus, writes Eva Sirinathsinghji, apparently due to the Bt insecticide they are engineered to express. Disruption caused by the transgenic cotton to mycorrhizal fungi, and the wider soil ecosystem, may underlie the low yields and poor pest resistance now endemic among Bt GM crops.
Decreased efficacy of the Bt trait in corn hybrids against bollworms
Coming after frequent reports of the growing resistance of pests to the Bt insecticidal toxin engineered into GM Bt crops, this article is further proof that claims of reduced pesticide spraying due to Bt crop adoption are ludicrously out-of-date.
Application techniques affect efficacy of crop chemistries
Patrick R. Shepard
Delta Farm Press, Dec 3, 2016
Corn earworm pest evolves resistance to multiple Bt insecticidal toxins
The corn earworm pest is showing increasing resistance to the insecticidal toxins engineered into GM Bt corn, according to a new study published in PLOS One.
The authors state that “Many sweet corn farmers in Maryland either have stopped growing” GM Bt corn or “are applying more insecticide sprays to compensate for the reduced control efficacy”.
They also note that the resistance is likely to increase and spread in future due to a number of factors, including
LONDON — The controversy over genetically modified crops has long focused on largely unsubstantiated fears that they are unsafe to eat.
But an extensive examination by The New York Times indicates that the debate has missed a more basic problem — genetic modification in the United States and Canada has not accelerated increases in crop yields or led to an overall reduction in the use of chemical pesticides.