H2O2 level and related metabolites in rice induced by viruliferous leafhopper

Nonviruliferous second-instar nymphs fed on diseased rice plants for 8 days to acquire RDV. Approximately 80% of the adults were confirmed as viruliferous. About 30 viruliferous or nonviruliferous adults were starved for 2 h and then fed on 1 rice seedlings at the 2-leaf stage (approximately 10 cm in height) for 12 h.

The tested rice seedlings were analyzed for the contents of JA and SA, as well as transcript levels of JA or SA related genes via RT-qPCR assays. These experiments were performed in triplicate and repeated three times for each treatment. The tested rice seedlings were also examined for contents of H₂O₂, MDA, GSH, and GSSG, as well as the activity of GST, POD, and CAT using the respective kits or through treatment with DAB or H2DCFDA, as mentioned above.

To evaluate the effect of RDV infection on the plant penetration behavior of leafhoppers, viruliferous or nonviruliferous adults were subjected to the EPG assay. Each insect was continuously recorded for 3 h, and at least 13 valid biologically independent replicates were recorded.