Effect of phenolic acids derived from rice straw on Botrytis cinerea and infection on tomato

Phenolic compounds are widely used in different research fields, such as pesticides, medicines, and food. In this study, phenolic acids (PAs) were extracted from rice straw and were found to exhibit a strong inhibitory effect on Botrytis cinerea. B. cinerea mycelial growth and spore generation decreased by 86.18% and 69.10%, respectively, following 0.2 g/L phenolic acid treatment. Confocal microscopic images demonstrated that phenolic acids changed the morphology of B. cinerea. The addition of phenolic acids to B. cinerea-infected tomato leaves increased PAL (phenylalaninammo-nialyase) and PPO (polyphenol oxidase) activities, and decreased POD (peroxidases) and CAT (catalase) activities in the leaves, indicating that phenolic acids enhanced the tolerance of tomato leaves to B. cinerea by reducing oxidative stress. Chlorophyll fluorescence imaging revealed that phenolic acids could alleviate the destruction of the photosynthetic system of B. cinerea-infected leaves. These results provide new insight into the use of phenolic acids from rice straw, through which a complete green cycle of ecological production can be established. Copyright © 2020 Springer Nature B.V.