Some biological characteristics of Ooencyrtus pityocampae Mercet parasitoid of Brachynema signatum Jakovlev under laboratory conditions

Abstract

Background: Biological control is an important component of an eco-friendly approach in integrated pest management toprevent insecticide-resistant pests and minimize using pesticides. Ooencyrtus pityocampae (Mercet) (Hymenoptera:Encyrtidae) is an egg parasitoid of Brachynemasignatum (Hem.: Pentatomidae) in the pistachio orchards of Iran.Materials and Methods: In this study, biological characteristics, such as immature developmental time, adult longevity,parasitism percentage, and sex ratio were investigated.Results: Mean egg, larval, pupal, and total development time of O. pityocampae were 1.94±0.01, 3.42±0.03, 7.11±0.03,and 11.84±0.06 days, respectively. On five different food regimes (honey, water,10% honey-water, no food diet, honey, and B.signatum egg), adult longevity of females and males were 39.29±1.45, 38.5±3.33, 9.3±0.56, 5.05±0.91, and 19.81±0.63 daysand 40.05±1.56, 37.5±1.05, 7.8±0.29, 3.89±0.13, and 9.09±0.74 days, respectively. Female wasps were laying eggs during thefirst two weeks after adult emergence, and maximum parasitism (39.27±0.01 Eggs) was observed on day 3 of adult life span.Interestingly, sex ratio was positively correlated with B. Signatum egg mass size increased from 0.11 to 0.26 when the eggmass size increased from 10 to 40.Conclusions: These laboratory findings indicate that O. pityocampae may show good potential as a biocontrol agentagainst B. signatum under IPM programs.