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Southern rice black streaked dwarf virus (SRBSDV) is vectored by white-backed planthopper (WBPH), Sogatellafurcifera, in a circulative, propagative, and persistent manner.To better understand the relationship of virus-vector-host plant and the transmis sion mechanism of WBPH, this study evaluated the direct effects of SRBSDV on the feeding be havior of WBPH and determined the feeding behavior of viruliferous WBPH in relation to SRBS-DV inoculation.The third to fifth-instar nymphs of WBPH were allowed to feed for 48 hours on SRBSDV-infected rice plants, and then reared on the healthy seedlings for 8-15 days.E lectronic penetration graph (EPG) was used to monitor the feeding behavior of both the non viruliferous and viruliferous WBPH for 12 hours.Fifteen-22 days after the recording, total RNA was isolated from rice plant and used to determine whether or not the rice plant had been infected by RT-PCR.EPG showed that the duration of the 1st phloem contact (N4) was 15 times longer in viruliferous WBPH than in non-viruliferous WBPH.The mean duration of wa tery salivation (N4-a) of viruliferous WBPH was significantly longer than that of nonvirulifer ous WBPH.Meanwhile, the stepwise-backward logistic regression model showed that the total duration of N4 was the most significant variable (P =0.019) positively correlated with SRBS-DV inoculation, which was followed by the number of N4-a (> 10min) preceding N4-b(P =0.034).The study revealed that SRBSDV modified the feeding behavior of WBPH in a direct way and enhanced the inoculation efficiency.Salivation into phloem region might be the most important styler activity for the inoculation of SRBSDV.