A comparison of the toxicity of the botanical insecticide, Sirinol and two chemical insecticides, Mospilan and Consult, on two natural enemies of the pistachio psyllid, coccinellid predator (Oenopia conglobata)...

Abstract

Full Title: A comparison of the toxicity of the botanical insecticide, Sirinol and two chemical insecticides, Mospilan and Consult, on two natural enemies of the pistachio psyllid, coccinellid predator (Oenopia conglobata) and parasitic wasp (Psyllaephagus pistaciae)

The common pistachio psyllid, Agonoscena pistaciae, is one of the most important pests of pistachio tree. This pest has many natural enemies and some of the important ones are the coccinellid predator (CP) (Oenopia conglobata) and the parasitic wasp (PW) (Psyllaephagus pistaciae). In this research, the effect of three concentrations of Sirinol on the first and fourth instar larvae and the adult of O. conglobata and on the pupae and adult of P. pistaciae was tested and the toxicity of this insecticide was compared with that of two chemical insecticides, Consult and Mospilan. Topical bioassay was carried out in laboratory condition; however, to investigate the resistance stage of the parasitic wasp, a completely randomized experimental design was used in the field condition in 2010 and 2011. The results of these experiments show that the chemical pesticide, Mospilan, caused more mortality of all the stages of the two previously mentioned natural enemies than did Sirinol. The results show that Mospilan had a slightly harmful, moderately harmful, moderately harmful, and slightly harmful effect on the adult of the PW and the adult and the first and fourth instar larvae of the CP, respectively and Consult had a harmless, slightly harmful, slightly harmful, and moderately harmful effect on the named stages of the PW and CP respectively. On the other hand, Sirinol had a slightly harmful effect on the adult of PW, but a harmless effect on the other stages; consequently, it falls into the category of International Organisation for Biological Control (IOBC). The field experiments conducted in 2010 and 2011 showed that 15.79% Mospilan, 13.8% Consult, and 6.49% Sirinol caused the mortality of the larvae and pupae of the PW. This research showed that Sirinol which caused very low mortality of the natural enemies of pistachio psyllid can be used in Integrated Pest Management (IPM) program in pistachio orchards.

Keywords: Oenopia conglobata, Psyllaephagus pistaciae, insecticide, Sirinol, Consult, Mospilan