Behavioral responses of brown planthopper and white-backed planthopper to BPH-resistant rice varieties

Comparison among the behavioral reactions of brown planthopper (BPH) Nilaparvata lugens Stal and white-backed planthopper (WBPH) Sogatella furcifera (Horvath) fed on four BPH-resistant (ASD7, IR36, JX89 and Mudgo) and one BPH-susceptible (TN1) rice varieties were conducted. BPH showed evident non-preference reaction to these resistant varieties, and there were significant differences between BPH (4th after inoculation)/WBPH (8th after inoculation) densities on resistant and susceptible varieties, while the planthopper densities on BPH-resistant varieties, except Mudgo, were similar. On the same BPH-resistant variety, the perference rate on WBPH were significantly higher than that of BPH. There was no time regularity of planthopper density on any rice variety. Both the feeding amounts of BPH and WBPH on resistant varieties were markedly lower than those on TN1, while in comparison with the feeding amounts of BPH on IR36/JX89, those of WBPH were obviously higher. Contrarily, the probing wound number of the two planthopper species on resistant rice varieties were much more than that on TN1, but those of WBPH on ASD7/JX89 were much less than those of BPH. Consequently, there is a negative correlation between the probing wound number and feeding amount of planthopper on any rice variety.