According to a study conducted by scientists at the University of Stirling, insect pests that attack crops have extraordinary abilities to develop resistance to greener pesticides, and a new approach to managing resistance risks is required.
Agriculture Needs Fresh Approach To Tackle Insect Resistance To Biopesticides
Agriculture's response to pesticide resistance has been to seek new pesticides in an endless race to keep up with evolving pests for more than 70 years, as per ScienceDaily.
Researchers now propose a new way for farmers to get off the treadmill as they embrace the ongoing green revolution in pest control by using biopesticides derived from natural organisms.
As the world's population grows, the evolution of resistance to biopesticides, a critical tool in the development of sustainable crop protection, has huge implications for global food security.
To address this emerging challenge, researchers used principles from fundamental evolutionary ecological science to develop a practical framework for managing the risks of biopesticide resistance evolution.
Farmers can help manage resistance risks by planting a wider variety of crops and using multiple biopesticides, according to the researchers.
The study was supported by a Newton Fund international collaboration between the Biotechnology and Biological Sciences Research Council (BBSRC) in the United Kingdom and the So Paulo Research Foundation (FAPESP) in Brazil, as well as the Swedish Research Council (Vetenskapsrdet).
Scientists from the University of Stirling's Faculty of Natural Sciences collaborated with colleagues from the University of Gothenburg and So Paulo State University to conduct a synthesis of existing biopesticide research and concluded that resistance evolution is already occurring and will likely become widespread as biopesticide use grows.
Senior Lecturer in Biological and Environmental Sciences at the University of Stirling, Dr Matthew Tinsley, stated: "People are naive; they believe that because biopesticides are derived from natural sources, pest resistance will be more difficult to evolve, but we still need to be concerned about pest resistance to these new agents.
The development of biopesticides takes five to ten years, so if we wait, we will lose these new agents because pests will have evolved.
Post-doctoral researcher Rosie Mangan from the University of Stirling added, To avoid the same cycle of invention and loss that has occurred with chemical pesticides, novel resistance management approaches are required for these crop protection products.
Farmers, according to Mangan's point of view, can help manage resistance risks by planting a wider variety of crops and employing multiple biopesticides.
This will help to slow the spread of resistance and keep biopesticides effective in the long run.
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How Pesticide Resistance Develops
Repeated use of the same class of pesticides to control a pest can cause undesirable changes in the pest's gene pool, leading to pesticide resistance, another type of artificial selection, as per the Michigan State University.
Because of their unique genetic makeup, a small proportion of the pest population may survive the first application of a pesticide.
These individuals pass on resistance genes to the next generation. Subsequent pesticide applications increase the proportion of the population that is less susceptible.
The population gradually develops resistance to the pesticide as a result of this selection process.
Pesticide resistance has been observed in over 500 insect, mite, and spider species worldwide.
The two-spotted spider mite is a pest of most fruit crops and is notorious for developing miticide resistance quickly.
If a small proportion of the insect population survives insecticide treatment, selection for resistance can occur.
These extremely rare resistant individuals are capable of reproducing and passing on their resistance to their offspring.
If an insecticide with the same mode of action is used on this population repeatedly, an even greater proportion will survive.
Eventually, the once-effective product loses control of the resistant population.
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