Occurrence of Rhynchaenus empopulifolis in a Populus euphratica forest in Jinta County, Gansu Province, China, and methods for its control

Rhynchaenus empopulifolis is the most important insect pest damaging Populus euphratica forest, and the incidence is becoming increasingly serious. In the present study, we found that when temperature above 10 ℃, it recovers activity and immediately causes harm to P. euphratica in Jinta County. The larva begins to pupate in May, and is most abundant in early June. We investigated the effectiveness of the control of this pest by separately spraying 5% Cypermethrin Emulisible Oil 1 000 times, and 2.5% Deltamethrin Emulisible Oil 2 000 times. According to the results, spraying 5% Cypermethrin Emulisible Oil 1 000 times had a significant control effect that average good leaf rate was higher than water treatnent in early April. Moreover, the average correct mortality of the pupae was 99% and 100%, and with this control strategy, the adults almost could not complete eclosion.