Studies on synergistic effect of fluorescent brightener OB on Spodoptera exigua nucleopolyhedrovirus(SeNPV)

The synergistic effect of fluorescent brightener OB on Spodoptera exigua nucleopolyhedrovirus was studied using Spodoptera exigua Hübner as testing insect in laboratory. The testing results showed that the synergy was enhanced as the increase of the concentration of OB in 0.25~1%, and the highest efficiency ratio was 10.2. But the synergy was decreaced with the instar increasing from 2end to 4th star.