Metabolomic and Transcriptomic Investigation of Metabolic Perturbations in Oryza sativa L. Triggered by Three Pesticides

Inappropriate application of pesticides often triggers molecular alterations in crops, which inadvertently disturbs metabolites and finally affects crop quality. Therefore, understanding the mechanism of action of pesticides on crops is essential for evaluating the potential environmental impact of pesticides. Our findings indicated that three typical pesticides, including herbicide butachlor, insecticide chlorpyrifos, and fungicide tricyclazole, induced the expression regulation of different key genes, exhibiting considerable distinction on metabolic responses in rice (Oryza sativa L.). Butachlor mainly affected five carbohydrate metabolism pathways (38.5%), and more than 48.0% of differentially expressed genes (DEGs) were involved in the starch and sucrose metabolism as well as photosynthesis, thereby disturbing the distribution of starch-sucrose. Chlorpyrifos dramatically affected six amino acid metabolism pathways (60.0%), and key DEGs mainly enriched in the aspartate and glutamate metabolism, inducing an increase in free amino acid contents (up to 29.02% of the control) and degradation of soluble proteins (down to 48.72% of the control). Tricyclazole remarkably affected six fatty acid metabolism pathways (53.9%) and significantly upregulated DEGs which primarily code oil-body membrane proteins, which resulted in the decline of saturated fatty acids (palmitic acid and stearic acid) and the increase of unsaturated fatty acids (linolenic acid and octadecadienoic acid). These findings provide a molecular-scale perspective on the response of crops to pesticides.