July 26 2018 12:00 AM

The discovery could lead to new class of commercial herbicides. But further study is needed.


A team of engineers and scientists at the University of California, Los Angeles has discovered a new and potentially highly effective type of weed killer, according to a story published by the website ScienceDaily. This finding could lead to the first new class of commercial herbicides in over 30 years. This is good news for those who maintain landscapes or grow crops, as weeds continue to develop resistance to the chemicals currently used to eradicate them.

There is also a potential for this genomics-driven approach to not just kill weeds but help humans live. It may be useful in developing new antibiotics and powerful cancer-fighting drugs.

Microbes in soil naturally produce chemicals that kill its plant competitors. At the same time, ithe microbes must have immunity to their own poisons.

The team found the new herbicide by searching the genes of thousands of fungi for one that might provide immunity against fungal poisons. This approach is known as "resistance gene-directed genome mining."

The herbicide acts by inhibiting the function of an enzyme necessary for a plant’s survival. When this pathway is disrupted, the plants die.

This pathway is not present in mammals, including humans. But a commercial product that uses it would require more research and regulatory approval.

"An exciting aspect of the work is that we not only discovered a new herbicide, but also its exact target in the plant, opening the possibility of modifying crops to be resistant to a commercial product based on this herbicide," said study co-principal investigator Steven Jacobsen, a professor of molecular, cell and developmental biology at UCLA and an investigator at the Howard Hughes Medical Institute.

"We are looking to work with large agrochemical companies to develop this promising lead further."

To confirm the effectiveness of the new herbicide, the UCLA team tested the fungus-produced product on a common plant called Arabidopsis. In the experiments, the product killed the plants after they were sprayed with it. They also implanted the resistance gene from the fungus into Arabidopsis genomes. The plants that had the resistance gene implanted in them were immune to the herbicide.

"The emergence of herbicide-resistant weeds is thwarting every herbicide class in use; in fact, there has not been a new type commercialized within the last 30 years," said Yan Yan, a UCLA chemical engineering graduate student and lead author of the paper. "We think this new, powerful herbicide -- combined with crops that are immune to it -- will complement urgent efforts in overcoming weed resistance."