LAUSR

BACKGROUND The tea green leafhopper, Empoasca flavescens is the most important pest of tea plants in China. And the Mymarid attractants based on volatiles from leafhoppers' feeding (HIPVs) and oviposition (OIPVs) were formulated and tested as a novel pest control agent against the leafhopper in tea plantations. RESULTS Results showed that two mymarids species, Stethynium empoascae and Schizophragma parvula had a reducing effect on leafhopper populations. The HIPVs and OIPVs were identified, and bioassayed to screen the key synomones which showed strong attraction to the mymarids. They were formulated into different blends, of which Field Attractant 1 which was composed of linalool, methyl salicylate, (E)-2-hexenal, perillen and α-farnesene at ratio of 1:2:3:58:146 (20 mg/lure) showed the strongest attraction to the mymarids. In field trials with the attractant, the average parasitism rate (60.46±23.71%) of tea leafhoppers by the two mymarids in the attractant-baited area was significantly higher than that (42.85±19.24%) in the CK area. Also, the average leafhopper density (46±30 per 80 tea shoots) in the attractant-baited area was significantly lower than that (110±70 per 80 tea shoots) in the CK area. CONCLUSION This study showed that a synthetic blend of key volatiles from HIPVs and OIPVs at an optimal ratio can be formulated into an attractant, which has the potential to attract and retain wild mymarid populations to suppress leafhopper populations in infested tea plantations so as to reduce or avoid the spraying of insecticides. This article is protected by copyright. All rights reserved.