New research published in Bioorganic & Medicinal Chemistry Letters identifies five chemicals that trigger rice plants to fend off a common pest – the white-backed planthopper, Sogatella furcifera.
This paves the way for pesticides being replaced by chemical triggers that make plants defend themselves against insects.
The widespread use of pesticides to control insects that destroy crops has raised environmental concerns because of the detrimental effect on ecosystems. One problem is that many pesticides kill indiscriminately.
Plants have natural self-defence mechanisms that kick in when they are infested with pests like the white-backed planthopper, Sogatella furcifera, that is a pest for rice crops. This mechanism can be switched on using chemicals that do not harm the environment and are not toxic to the insects or their natural enemies.
In the new study, researchers from Zhejiang University in China developed a new way of identifying these chemicals. Using a specially designed screening system, they determined to what extent different chemicals switched on the plants’ defence mechanism.
The team designed and synthesized 29 phenoxyalkanoic acid derivatives. Of these, they identified five that could be effective at triggering the rice plants to defend themselves.
The researchers used bioassays to show that these chemicals could trigger the plant defense mechanism and repel the white-backed planthopper. This suggests that these chemicals have the potential to be used in insect pest management.
“We demonstrate for the first time that some phenoxyalkanoic acid derivatives have the potential to become such plant protection agents against the rice white-backed planthopper,” said Dr. Yonggen Lou, one of the authors of the study and professor at Zhejiang University in China.
“This new approach to pest management could help protect the ecosystem while defending important crops against attack.”
The next step for the research will be to explore how effective the chemicals are at boosting the plants’ defenses and controlling planthoppers in the field.