Harvard and Monsanto speed up GE insect resistance in crops

Researchers for Harvard University and Monsanto have developed a new method to improve pest resistance in genetically engineered (GE) crops, according to a study in the scientific journal, Nature.

Using a technology called phage-assisted continuous evolution (PACE), the researchers were able to modify a common insecticidal protein to target insects that have developed a tolerance to it.

PACE technology, developed by Harvard chemical biology professor David Liu, allows scientists to evolve biological proteins up to 100 times faster than other commonly used methods. Use of the technology is said to dramatically speed up the discovery of proteins optimised for specific traits in crops, including insect control and herbicide tolerance.

Resistance to a class of proteins called Bt toxins is seen as a potential threat to the viability of GE crop varietals imbued with the protein to fight on-farm pests. Researchers were able to successfully modify a strain of Bt toxins to target insects with a tolerance to the protein’s “wild type”.

“Our findings establish that the evolution of Bt toxins with novel insect cell receptor affinity can overcome insect Bt toxin resistance and confer lethality approaching that of the wild-type Bt toxin against non-resistant insects,” the study reads.

The project between Monsanto and Harvard that produced the study began in 2013.

GE crops have become ubiquitous in major grain production in the US, representing 90 percent of major row crop acreage in the US. Biotech industry experts at the World Agri Tech forum recently said that using improvements in gene editing technologies to reduce the need for chemical inputs like fertilisers, pesticides and herbicides could improve consumer attitudes toward GE crops.