JOURNAL OF ENTOMOLOGICAL RESEARCH
Year:2009 | Volume:1 | Issue:1 (1)|Papers Count:8

Danaus chrysippus L. (Lep.: Nymphalidae) is the most important pest on Calotropis procera Ait. in Bushehr, Iran. The larvae feed on the leaves and make some damages and losses on host. This study was carried out on D. chrysippus life cycle in Bushehr from 2006 to 2007. The sampling was carried out weekly by two stage cluster sampling method in nature. For the life cycle studies, the eggs were collected from the nature and were developed in petri dishes and 10×12 plastic dishes from egg to adult under laboratory conditions (25±2oC and 22±2oC, %60±10 RH and 16/8 L: D). The results showed that the first adults emerged gradually in February 2006. During the summer and the winter in 2007, any forms of this butterfly have not been observed in Abpakhsh. Incubation period of eggs were 3.4 and 4.5 days; Developmental period of larvae were 12.5 and 19.1 and for pupae 9.8 and 14.6 days under temperatures of 25 and 22oC at the laboratory conditions respectively. The total period from egg to adult was 26.07±0.8 and 37.08±0.5 days in 25 and 22oC respectively at laboratory conditions. This butterfly had 5 overlaped generations in a year.

Sugarcane stem borers are the most important pest of this crop in the world and Iran. We studied the fluctuation of eggs population of the stem borer Sesamia nonagrioides Lefebvre and its parasitism by Platytelenomus hylas Nixon in Karoun AgroIndustry Company, (KhuzestanIran) in 2005-2006. This study was conducted in two years. In the first year a Ratoon field and in the second year a Plant field cultivated with variety of CP48-103 were selected for sampling program. Samples were taken weekly; numbers and percent parasitism of eggs, numbers of sugarcane stem and the height of plants were recorded in each sampling occasion. Results showed that there were more eggs in low density of sugarcane stems. The peak of the stem borer oviposition was in the mid of August 2005 in the Ratoon field, and it was in mid of June 2006 in Plant field. The percent parasitism increased with increasing the plant height in Ratoon and Plant fields. The peak of percent parasitism was 67.8 when the plant height was 96.2cm in Ratoon field in the beginning of July 2005, and 78.8 when the plant height was 78cm in Plant field in the mid of April 2006.

Leafminers of vegetables are the major pests of greenhouse cucumber in Iran. One of the reasons for repeated outbreaks of leafminer during recent years, is attributed to the vast application of some ineffective insecticides. The purposes of this project were to evaluate the efficacy of new biorational insecticides, cyromazine, spinosad and oxymatrine. The toxicities of these products were compared with abamectin as a conventional insecticide in Iran. Effectiveness of cyromazine (75, 150 mg/L), oxymatrine (3, 9 mg/L), spinosad (48, 96 mg/L) and abamectin (12, 24 mg/L) based on active ingredient were studied on the early larval instars (L1, 2), the third instar larvae (L3), the pupal stage and 2-day old adults of Liriomyza sativae in completely randomized design. The bioassay tests showed that spinosad, cyromazine and oxymatrine had more than 95% effectiveness and abamectin at low concentration had the least effectiveness (23.18%) on the early instar larvae. For the pupal stage, oxymatrine (9 mg/L) with 51.6% mortality and spinosad (48 mg/L) with 0.89% had the most and the least effectiveness respectively. Bioassay of adults showed that spinosad 96 mg/L with 92.1% mortality and cyromazine 75 mg/L with 6.2 % had the most and the least effectiveness respectively. Toxicity of the biorational insecticides on the developmental stages of L. sativae showed that larval and pupal stages were most (23.18-100%) and least (0.89-51.63%) susceptible to insecticides respectively. The low and high concentrations of each insecticide no significant effect on the larval stages. Laboratory trials revealed that abamectin formulated in Iran, could not control leafminer effectively in the greenhouses of Iran.

Pomegranate fruit moth, Ectomylois ceratoniae Zeller (Lepidoptera: Pyralidae), is the most important factors for decreasing quality and quantity of pomegranate in Iran. Due to biology of the pest like egg laying place and larval feeding behavior, application of pesticide is not practical; consequently losses of this valuable product are too much. Application of Sterile Insect Technique (SIT) is a method that is used for a few insect with the special condition. This research has been done for evaluation practical control of this pest with application of nuclear methods. E. ceratoniae reared on the artificial diet (28±2oC, 60±5% RH, 14 hours light and 10 hours darkness). Young and old pupa separated and were irradiated at different dose range of 0 (Control) and 40, 60, 80, 100, 120, 140, 160 Gy. The adults after eclosion crossed according to the following situations: Irradiated male×wild female, irradiated female×wild male, and irradiated male×irradiated female and wild male×wild female. The result shows that the best controlling formula of pomegranate fruit moth is irradiated males×irradiated females and the best controlling doses of young and old pupa are 120 and 160 Gy respectively.

Batrachedra amydraula (Ba) is one of the most important date pests in Khuzestane province. In this research cluster sampling method was carried out for studying the geostatistical models of its distribution during 2002-2005. Sites of sampling (including 65 plots) were distributed from 25.59 to 32.08 geographical longitudes and 48.8 to 50.1 geographical latitude in Khuzestane province. Variography of distributions on different sites were studied based on Spherical, Exponential, Linear, Linear to sill and Gaussian models and their Kriging maps were drawn. Results showed that the best model for the pest was Exponential. Nuggets were 0.52, 0.43 and 0.47 for three years, respectively. These results showed that bias of the pest damage estimation was low at the distances less than whithin sampling space. Effective ranges of variograms were 239.5, 228.2 and 354.8 kilometers for three years respectively. The data indicate that the mean damages of the pest are not correlated at more than these distances. Sill of models were 1.047, 0.855 and 1.152 for three years respectively which indicated that the population distribution in the region. Results of this research confirmed that the geostatistic method was a precise sample and low cost for evaluating the pest damage in integrated pest management.

Vegetable leafminer Liriomyza sativae Blanchard (Dip.: Agromyzidae) is a serious pest on cucumber in the greenhouses of Iran. The high densities of the pest might be resulted in sever damages to the plants. To control the pest, farmers treated their plants several times with different insecticides. Regarding adverse effects of pesticides in the present study feeding and oviposition preference of Liriomyza sativae on greenhouse cucumber cultivars have been studied. The experiment conducted in the greenhouse under condition of 27±2oC, 60±5% RH and 16L: 8D. Using 7 cucumber varieties with 4 replications. Overall, the results indicated that no variety had the highest resistsnce or lowest susceptibility, But using varieties with the few feeding punctures and larval mines (Janett), could be suggested on IPM program aginst this pest.

The Ichneumonid fauna (Hym.: Ichneumonidae) was investigated in different regions of Yazd and vicinity during 2006-2008.A total of nine species were collected and identified. According to the available literature, the 3 species which marked with an asterisk are reported for the first time from Iran.Diplazon laetatorius (Fabricius, 1781)Anomalon foliator (Fabricius 1798)*Ophion ventricosus Gravenhorst, 1829Ichneumon caloscelis Wesmael, 1854Netelia arimeniaca Tolkanitz, 1971Meringopus calescens (Gravenhorst, 1829)Cryptus spinosus Gravenhorst, 1829Cryptus viduatorius Fabricious, 1804*Cryptus inculator (Linnaeus, 1758)*Some information relating to the morphological characters, host range and geographical distribution of three new species records were presented and discussed.

During 1997-1998 a faunistic study was carried out on mites (Acari) associated with grapevine in Safiabad, Khuzestan, south Western province of Iran. A total 39 species belonging to 37 genera and 27 families were identified respectively. The new mite records in Iran indicated by the asterisk. The most abundant predator, scavenger and pest mites were Androlaelaps casalis Berlese (Laelapidae), Oppia yodai Aoki (Oppiidae) and Tenuipalpus granati Sayed (Tenuipalpidae) in Dezful region. Among collected specimens, 12 species were new records for Iran. The newly recorded mites are listed as follows.Mesostigmata                                                                  PhytoseiidaeLaelapidae                                                                      Euseius obtectus* Khan, Chaudri & TahirPseudoparasitus holaspis* (Oudemans)                             Proprioseiopsis sp.Androlaelaps casalis (Berlese)                                           Anthoseius rhenanus (Oudemans)Hypoaspis aculifera Ganestrini                                          Amblyseius reductus* WainsteinAscidae                                                                          MacrochelidaeProtogamasellus sp.                                                        Macrocheles scutatus* (Berlese)Lasioseius matthyssei* Chant                                           AmeroseiidaeLasioseius phytoseioides* Chant                                       Ameroseius pavidus* KochGamasellodes bicolor (Berlese)                                         Pachylaelapidae                                                                                    Pachylaelaps karawaiewi (Berlese)