Entomology

The present investigation was aimed to analyse the chemical composition of essential oil isolated from Heracleum persicum Desf. ex Fischer and assess its lethal and sub-lethal effects against Tribolium castaneum (Herbst). Essential oil from hydro-distilled seeds of H. persicum was analyzed by gas chromatography-mass spectrometry (GC-MS), and hexyl butyrate (50.58%), octyl acetate (9.80%) and hexyl hexanoate (8.75%) were found as principal constituents. Repellent activity, contact and fumigant toxicity and antifeedant effects of this oil were assessed against the adults of T. castaneum. The essential oil strongly repelled T. castaneum adults even at the lowest concentration (0.035 μL cm -2 ). Complete repellency (100%) occurred when the highest concentration (0.212 μL cm -2 ) was applied for 8 h. T. castaneum was very susceptible to H. persicum oil at both contact and fumigant bioassays. In the fumigant toxicity, essential oil killed the larvae, pupae and adults and significantly decreased larvae emerged from treated eggs. LC 10 to LC 40 values of fumigation adult's bioassay as sub-lethal concentrations were used to evaluate the antifeedant effects. H. persicum essential oil has significant antifeedant effects on T. castaneum adults and decrease of feeding happened when oil concentrations increased. The results of the present study indicate that essential oil of H. persicum, with wide bio-effects on T. castaneum, is a source of biologically active agents which may potentially prove to be efficient insecticides.

Phytoseiid mites are most known family among the predator mites because of their achievement to control of mite and insect pests. The aim of this investigation was to study of Similarity and Uniformity indexes of dominant Phytoseiid mites on the three hosts including plum orchards, adjacent raspberry hedgerows and predominant orchard floor vegetation. To this order, sampling was carried out once two weeks from three plum orchards, adjacent hedgerows raspberry shrubs and dominant orchard floor vegetation with equalizing of leaf surfaces from different hosts in the central area of Guilan province within deferent season of 2009-2010. Phytoseiid mite species after separation, transparency and slide preparation were identified according to valid identification keys. The results were recorded in Excel software and analyzed. During this study 10 Phytoseiid mites’ species were identified. Similarity indexes (J') for Phytoseiid mites on the adjacent raspberry hedgerows was more than the ...

European ash, Fraxinus excelsior L. (Oleaceae), is one of the valued trees from green space of Ardabil city. A variety of pests have damage on European ash in this region and armored scales are among most important pests of these trees. Despite the fact that armored scales have high damage on Europen ash in Ardabil city, has not been done comprehensive study yet. In this order, infected branch with armored scales were collected from throughout city and then transport to entomology laboratory, university of Mohaghegh Ardabili. Samples were carefully examined by stereomicroscope and the microscopic slides were prepared after separation and clear up. Two armored scale species including Lepidosaphes ulmi L. with wide detrimental and dispersal and Diaspidiotus slavonicus (Green) with low detriment and dispersal were identified that both have one generation per year. L. ulmi hibernate as egg batch under female shield and moving nymphs emerged from shields amidst of May. In middle June, th...

Cotton aphid, Aphis gossypii Glover, is an important pest of the cucumber, especially in the greenhouse. In this research intrinsic rate of increase and mean relative growth rate of cotton aphid on two cultivars of cucumber (Royal and Storm) in laboratory conditions under 25±1° C, 60 ± 5 R.H and 14:10 LD were studied in two separated experiments. In the first experiment, the parameters such as duration of fertility, reproductive rate and intrinsic rate of increase (rm) were estimated. The experiments were calculated in the completely randomized design with 40 replicates and in 2 to 3 leaf stage of cucumber plant. The experiment began with the first instars. After reaching aphids maturity, number of nymphs that born per aphids were counted and then removed daily. In the second experiment, for determine of mean relative growth rate (MRGR) on two cultivars, ten nymphs (on day old) weighed and transferred into plastic clip cages on the plant leaf, individually. The aphids were allowed t...

Colorado potato beetle, Leptinotarsa decemlineata (Say), is an important pest of potato throughout the world. Here, the effects of six potato cultivars including 'Arinda,' 'Sprit,' 'Markiez,' 'Lotta,' 'Santae,' and 'Agria' were studied on nutritional indices, digestive enzymes, and some components involved in intermediary metabolism of L. decemlineata. Nutritional indices of the larvae and the adults were significantly different followed by feeding on various potato cultivars. The individuals fed on Agria showed the highest activity of digestive proteases although cathepsin B demonstrated same Activity on Santae and Lotta. The highest activity of a-amylase was found in the larvae fed on Arinda, but the adults demonstrated the highest amylolytic activities on Santae and Agria. Both larvae and adults of L. decemlineata fed on Santae revealed the highest aand b-glucosidase activities. No significant differences were found in lipase activity of larvae, but the highest lipase activity was found in the adults fed on Santae. The highest activities of transaminases were found in the larvae and adults fed on the Agria except for c-glutamyl transferase. In case of aldolase, the highest activities were observed in the larvae and adults fed on Santae and Sprit. The highest activities of lactate dehydrogenase were obtained in the larvae and adults fed on Santae. The highest amount of low-density lipophorin was measured in both individuals fed on Santae. There were no significant differences in high-density lipophorin amount of adults, but the highest value was found in the larvae fed on Agria. The lowest amounts of protein and triglyceride were observed in both individuals fed on Santae and Agria, respectively. These results revealed Santae is the most suitable cultivar for L. decemlineata based on digestion and intermediary metabolism findings, but Lotta is an unsuitable cultivar and could be considered for integrated pest management.

During 2009-2010 an investigation was carried out for identification of raspberry shrubs mites fauna in the central area of Guilan Province. In this study 69 species from 50 genera, 41 families and 5 orders were collected and identified. Among identified specimens 7 species were new for Iran and 33 species for Guilan Province mites fauna. The list of identified species is as follow. New species records for Iran and Guilan Province marked with two and one asterik respectively. Acarus siro Linnaeus, 1758, Rhizoglyphus robini Claparede (1869)*, Tyrophagus putrescentiae (Schrank, 1781), Glycyphagus destructor Schrank, 1781 (Acaridae); Raphignathus hecmatanaensis Khanjani & Ueckermann, 2003 (Raphignathidae); Stigmaeus pilatus* Kuznetzov, 1978, Zetzellia mali* (Ewing) Summers, 1960 (Stigmaeidae); Tetranychus urticae Koch, 1836, Bryobia rubriculus* (Schenten, 1857), Panonychus citri (McGregor), 1916, Oligonychus bicolor (Banks, 1894) (Tetranychidae); Tydeus sp. *, Brachytydeus sp.* (Tydeid...