نشریه نامه انجمن حشره شناسی ایران
سال سی و پنجم شماره 4 (پیاپی 63، زمستان 1394)

Predation rate is basic to any investigation of prey-predator interaction and a major component in the selection of predators for biological control. The predation rate of variegated lady beetle, Hippodamia variegata (Goze), fed on different densities (20, 40, 60, 80 and 100) of third instar nymphs of cotton aphid, Aphis gossypii Glover, was studied under laboratory conditions (25 ± 1 °C, 65 ± 5% RH and a photoperiod of 16L: 8D h). The net predation rates (C0) using age-stage, two sex life tables for 20, 40, 60, 80 and 100 aphids were calculated as 1547.50, 4011.91, 4450.78, 5300.20, 5305.73 prey nymphs, respectively. The mean consumption rates for male and female predators increased as prey density increased. The predation rate for both sexes also increased with increasing prey density. The lowest and highest predation rates for female were 1547.50 and 5305.73 prey nymphs at densities of 20 and 100 aphids, respectively. The transformation rate from prey population to predator offspring (Qp) decreased as prey density increased. It was concluded that any increase in the density of third instar nymphs of A. gossypii will result in significant effects on predation parameters of H. variegata.

This report is part of a national project for gathering and classifying the arthropod seed feeders in different provinces of Iran between 2008–2014. In this paper, nineteen host species with their areas of distribution are presented for twelve species of seed beetles (Chrysomelidae: Bruchinae). Most of the identified host plants (84%) belong to the family Fabaceae (Leguminosae). In addition, all known hosts for these beetles are discussed. The identified species in this study were confirmed by Dr. Alex Delobel in the Natural history Museum of Paris. The studied material is deposited in the arthropod collection of Research Institute of Forests and Rangelands.

The effects of four corn hybrids, Keynes540, Keynes410, KSC260 and KSC400, were investigated on life table parameters of the beet armyworm in a growth chamber that was set at 25 ± 1 ºC, 65 ± 5% RH and 16:8 (L: D) photoperiod. The highest survivorship (lx) of adults were 0.77, 0.70, 0.62 and 0.58 on KSC260, Keynes410, Keynes540 and KSC400, respectively. The highest age-specific fecundity (mx) of females which were emerged from the larvae being fed on above-mentioned hybrids were recorded 28.75, 21.70, 20.37 and 16.33 female/ female/ day, that occurred at the days 39, 40, 41 and 45, respectively. The females reared on KSC400 showed the lowest net reproductive rate (R0), while the highest R0 was recorded on KSC260 hybrids. The intrinsic rate of natural increase (rm) ranged from 0.1028 to 0.1370 day-1 of which the lowest was on KSC400. The lowest and highest values of finite rate of increase (λ)were obtained on KSC400 and Keynes540, respectively. The longest mean generation time (T)(35.37 ± 0.83 days) was observed on KSC400 and the shortest one (30.67 ± 0.93 days) was on Keynes410. The results showed that KSC400 was the least suitable host for S. exigua.

A suitable diet and oviposition substrate are two basic needs for successful mass rearing of Orius spp. and this may reduce their production costs. The effect of various foods containing eggs of Ephestia kuehniella and Sitotroga cerealella with various pollens were investigated on the biological parameters of O. albidipennis in the laboratory. Moreover, survival, hatching rate and fecundity of the predatory bug on various natural substrates were compared. Nymphal developmental time of the bug on diets including E. kuehniella and S. cerealella varied from 13 to 14.2 and 14 to 15.3 days, respectively. The nymph and adult survival and consumption rate were not significantly affected by the dietary treatments. Because of a more rapid development with food containing eggs of E. kuehniella, they are the best nymphal diets for mass rearing of O. albidipennis. It must be noted that S. cerealella eggs are six times cheaper than E. kuehniella eggs. Therefore, the foods containing eggs of S. cerealella may be more economic for mass rearing of the bug despite a slower development of nymphs that fed on them. Also, composition of S. cerealella and date palm pollen is the most suitable diet for mass rearing of O. albidipennis adults due to a higher fecundity and longevity of the adults and lower costs of the diet. Female longevity, total eggs and hatching percentage of the predatory bug on Sedum ternatum were significantly higher than other natural substrates. These results may have practical implications for mass rearing of O. albidipennis as part of a biological control program.

Haplothrips zabolius sp. n. is described from two plant species, Cynodon dactylon (Poaceae) and Plantago lanceolata (Plantaginaceae) from the southeast of Iran. The new species is apparently close to some grass-living Haplothrips species: H. aculeatus (Fabricius), H. eragrostidis Priesner and H. hukkineni Priesner. Most specimens of the new species have only one sense cone on the antennal segment III, but it is unusual among Iranian members of the genus in having another sense cone on the antennal segment III in a few specimens.

The imported willow leaf beetle, Plagiodera versicolora is one of the main pests of forest trees worldwide including Iran. Activities of α- and β-glucosidases in the midgut of P. versicolora adults were studied in this research. The results showed a higher α- glucosidase activity of adultsthan β-glucosidase. The optimal pHs for α- and β-glucosidases activities were found to be 6 and 9, respectively. Optimal temperatures for the enzymatic activities were recorded at 30 and 25 °C, respectively. Concentration of 0.5 mM K significantly minimized the activity of α- glucosidase and maximized the activity of α-glucosidase in presence of Ca2. The activity of β-glucosidase was decreased by adding Mg2 and Zn2. 5 mM concentration of K had the most inhibitory impact on β-glucosidase activity, while 0.5 mM concentration of Na showed the most positive effect on the enzyme activity. The Km of midgut α- and β- glucosidase was 0.36 and 2.03 mM and the Vmax value was 5.46 and 18.51 μmol/min/mg protein, respectively.

A survey was conducted to study the fauna of the subfamily Ophioninae (Hymenoptera: Ichneumonidae) in southern Iranian provinces of Fars and Hormozgan. The specimens were collected using Malaise traps, light traps and sweep nets from a variety different habitats between 2011 and 2013. A total of twelve species of three genera (Enicospilus Stephens; Ophion Fabricius and Eremotylus Forster) were identified, of which the five species Enicospilus flavocephalus (Kirby), E. merdarius (Holmgren), E. monostigmata (Vollenhoven), E. ramidulus (L.) and Eremotylus sibiricus Szépligeti are newly recorded from Iran. This work raise the number of ophionines of Iran to 26 species and four genera. A key to the Iranian genera and species of Ophioninae is provided.

During a survey on pistachio, Pistacia vera L., pests in Isfahan, Iran, in 2015, some lepidopteran larvae living and feeding inside galls of the wrinkling pistachio aphid, Forda hirsuta Mordv., were observed. After laboratory rearing of these larvae, the moths were identified as Altenia mersinella (Staudinger, 1879) (Lep.: Gelechiidae) by the third author. This species has previously been reported from Turkey, Cyprus, Syria, Lebanon and Palestine but it is the first report of this species from Iran. Based on the available literature, this is also the first record of a host plant for this species.

During a survey in 2015, three dark-winged fungus gnat species, Bradysia odoriphaga Yang & Zhang, 1985, Bradysia trivittata Staeger, 1840and Scatopsciara atomariaZetterstedt, 1851 were identified and recorded here from Iran for the first time. The genus Scatopsciara Edwards, 1927 is newly recorded from Iran as well. The identification of specimens were confirmed by Dr Kai Heller (Germany). The sciarid species were collected on the pine trees, Pinus mugo Turra, in the urban green landscapes of the city of Mashhad, Khorasan-e Razavi province, Iran.