Components of male seminal fluids are known to stimulate fecundity and fertility in females of numerous insect species and paternal effects on offspring phenotype are also known, but no studies have yet demonstrated links between male effects on female reproduction and those on progeny phenotype. In separate laboratory experiments employing 10-day-old virgin females of Cheilomenes sexmaculata (F.), we varied male age and mating history to manipulate levels of male allomones and found that the magnitude of paternal effects on progeny phenotype was correlated with stimulation of female reproduction. Older virgin males remained in copula longer than younger ones, induced higher levels of female fecundity, and sired progeny that developed faster to yield heavier adults. When male age was held constant (13 days), egg fertility declined as a function of previous male copulations, progeny developmental times increased, and the adult weight of daughters declined. These results suggest that male epigenetic effects on progeny phenotype act in concert with female reproductive stimulation; both categories of effects increased as a consequence of male celibacy (factor accumulation), and diminished as a function of previous matings (factor depletion). Male factors that influence female reproduction are implicated in sexual conflict and parental effects may extend this conflict to offspring phenotype. Whereas mothers control the timing of oviposition events and can use maternal effects to tailor progeny phenotypes to prevailing or anticipated conditions, fathers cannot. Since females remate and dilute paternity in polyandrous systems, paternal fitness will be increased by linking paternal effects to female fecundity stimulation, so that more benefits accrue to the male's own progeny.

Females of Trissolcus agriope (Platygastridae) avoid host (Brachynema signatum) eggs parasitized by conspecifics or Ooencyrtus pityocampae (Encyrtidae), but females of the latter species will superparasitize and multiparasitize, although they mostly attack unparasitized eggs. Females of T. agriope were more efficient in the laboratory and parasitized more hosts in 24 and 48 h. In multiparasitized hosts, O. pityocampae was a superior larval competitor and could complete also development as a facultative hyperparasitoid. When females of both species foraged together, T. agriope parasitized significantly more than O. pityocampae, about 50%in both cases, although O. pityocampae almost doubled its parasitism rate as the exposure period was lengthened from 24 h to 48 h. When O. pityocampae followed T. agriope in sequential foraging bouts, the former species successfully parasitized more hosts than the latter. The advisability of co-releases of both species to improve biological control of first generation B. signatum in Iranian pistachio orchards is discussed.

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This research was conducted to develop a composite diet and compare its effects on developmental time, fecundity, survival rate, and life table parameters of pistachio green stink bug,Brachynema germariKolenati (Hemiptera: Pentatomidae) with a natural diet. The biological parameters of this pest were investigated using two-sex, age-stage life table theory on both composite and natural diets (25 ± 1°C, 50 ± 10% relative humidity, and a photoperiod of 16:8 [L:D] h). Based on the preliminary studies, the combination of the green beans (Phaseolus vulgarisL.), sunflower seeds (Helianthus annuusL.), and wild rue capsules (Peganum harmalaL.) was introduced into a composite diet. There was no significant difference between the longevity of each stage on diet treatments, but the mean fecundity of female fed on composite diet was about 196.48 ± 12.02 (eggs), which indicated a significant decrease than the fecundity of female fed on the natural diet (265.81 ± 11.67 eggs;P = 0.05,t-test). Also, main parameters of life table (r,R,T, and λ) for composite and natural diets were about 0.0863 ± 0.0031 d, 89.03 ± 13.33 eggs, 51.987 ± 0.536 d, and 1.091 ± 0.0034 dand 0.1023 ± 0.003 d, 128.75 ± 17.56 eggs, 47.454 ± 0.439 d, and 1.1077 ± 0.0037 d, respectively. There was a significant difference between these four parameters on both diets. Despite a significant decrease in fecundity with using composite diets, this diet can satisfy our needs now and the laboratory rearing of pistachio green stink bug did not stop over the year in the absence of host weeds and insect did not diapause.