بررسی بیولوژی، خسارت و شناسایی دشمنان طبیعی زنبور طلایی مغزخوار پسته ‭(Megastigmus pistaciae) ‬در منطقه قزوین .

The pistachio seed chalcid, Megastigmus pistaciae is known as an important pest of pistachio orchards in QaZvin area and especially damages the traditional orchards. This study was carried out in some pistachio orchards and to accomplish this investigation, about 2000 nuts, remained on trees from previous growing season, were conceted in late march and were held in net cages in orchards. In early April, 100 nuts were split every 5 days for determining larval mortality, pupation and adult emergence. According to data during' years 2002-2005, some over Wintering larvae had died, before pupation, and therefore, no parasite was observed. Pupation was began on mid-May and finished by early June. Pupal period lasted 8-12 days. Adults emergence, began from late May and ended by late June. Females laid one egg by its long Tarier in to the current season fruits and created first generation larvae. Larvae period of this generation, lasted about 5 weeks then pupated in the kernel and after 7-10 days adults through bore the pistachio shells, exit. Simultaneous to these adult's exit, the endocarp of some nuts hardened and consequenny were incapable to oviposit in to the nuts, and therefore they were unable to produce second generation so they have only one true generation and one partial per year. Damage level was different in variouse orchards, Ranging from 15 to 71 percent for Megastigmus pistaciae and 28-82 percent for Ewytoma. plotnikovi. Some larvae and pupa were parasited. The most important parasites, was: Syrtoptyx pistaciae, Eupelmus urozonus and also other parasites from Pteromalidae family were observed that are under identification.