Brassinosteroids Help Plants Rid Themselves of Pesticide Residues

Scientists from Zhejiang University in China are reporting that application of brassinosteroids to crops can help plants eliminate residues of certain pesticides. "Brassinosteroids may be promising, environment friendly, natural substances suitable for wide application to reduce the risks of human and environment exposure to pesticides," wrote Jing Quan Yu and colleagues, in a paper published by the Journal of Agricultural Food and Chemistry.

Brassinosteroids (BRs) are a group of more than 30 steroidal compounds that play important roles in plant growth and development. First identified twenty years ago, this class of compounds has also been implicated in plant responses to environmental stresses and in plant defense against bacterial, fungal, and viral pathogens.

The researchers treated cucumber plants with 24-epibrassinolide (EBR), one type of BR, then treated the plants with various pesticides, including chloropyrifos (CPF), a broad-spectrum commercial insecticide. EBR significantly reduced the toxicity and residues of the pesticides in plants, the scientists found. Application of EBR was correlated with increased expression of pesticide detoxification genes such as the P450 monooxygenase and glutathione S-transferase genes, suggesting that BRs enhance plant tolerance to pesticides by modulating the metabolic process of these pesticides.

The paper is available at http://dx.doi.org/10.1021/jf901915a