Journal of Entomological Society of Iran
Year:2001 | Volume:20 | Issue:2|Papers Count:10

An investigation was carried out on occurrence of Amblydromella kettanehi Denmark and Daneshvar (Acari: Phytoseiidae) on Pinus eldarica Medw. In different localities (Lavassanat, Damavand, Firouzkouh, Karaj, Lavizan and Chitgar Parks) of Tehran vicinity, during 19971999. Effects" of temperature, humidity, rain fall frost period on predatory mite population has been investigated on this host plant infested with false spider mite (Cenopalpus irani Dosse) in northern Tehran. Statistical analysis of the data indicated that identical impacts of climatic factors on mean number of predatory mite during sampling years (1997, 1998). Any increase/decrease of temperature / amount of the rain showed a positive / negative influences on number of predatory mite, while no direct effects could be observed for humidity factor, Any increase in amount of the rain, snow and number of freezing days during October-March of 1998-1999 lowered the predatory mite population, (statistically significant at 1%.). Developmental stages of A. kettanehi was studied on two-spotted spider mite under laboratory condition (23±5°C & 45±10 R. H.). Mean of developing time from egg to preoviposition was 5.5±1.5 days while length of egg to egg for the female was recorded on 11±4.5 days. Average daily and total fecundity of female predator feeding on new host recorded as 0.75±0.5 and 6.5±2.5 eggs respectively during 6 to 11 days of oviposition period. Overall mortality rate was 66.6%, whilst 20% occurred at larval stage.

For the German cockroach, Blattella germanica L. (Dictyoptera: Blattellidae), the permethrin resistance was assessed by glass Petri - dish at 15 mglm2 and insecticide impregnated paper %2, using first-instar nymphs of five strains from different hospital in Tehran, Iran. Each test was replicated three or four times with 10 nymphs, aged 2-3 days; mortality was scored 24h post - treatment. The reference susceptible strain showed L T50 of 10.2l±1.24 and 11.13±2.42 for glass - petri - dish and insecticide impregnated paper respectively. In four wild strains the resistance ratio (RR) varied from 0.48 to 2.16 for insecticicide impregnated paper test and from 0.54 to 2.24 following glass Petri - dish test. The results indicated that both methods of tests have similair ranges of RRs. Furthermore statistical analysis on S.E (LT50 and LT90) and slope of pro bit regression lines of all wild strains did not showed any significant differences in their responses to permethrin in both testing methods (p>0.05). Hence, it could be concluded that application of insecticide impregnated paper and glass petri dish are two reliable methods for measuring insecticide resistance in the first - instar of nymphs of Blattella Germanic.

In this survey seven species of the genus Haplothrips, namely H aculeatus, H jlavitibia, H.niger, H reuteri, H subtilissimus, H tolerabilis and H tritici were collected and identified. The species H subtilissimus is reported for the first time from Iran. All species except H tritici are new records for fauna of Fars province. This research includes a method for taxonomic study of thrips; identification key for the species of Haplothrips, host plants, altitudes, dates and locations for each species.

In recent years a new pest has occurred in west Azarbaidjan apple orchards. Nymphs of this pest fued on developing fruits and cause apples to become misshapen or develop corky warts in feeding sites. This injury lowers the quality offruits. In this research it was found out that mullein bug, campylomma verbasci, cause the injury. This bug is an active predator on apple trees and it’s population has remarkably increased recently. Feeding behavior of this pest was closely examined by confining the first generation nymphs and adults on apple branches in orchards. For labomtory observation of feeding habits, developing and oviposition rates, adults and immature stages enclosed on small apple twigs infested with various prey species. This bug has three generations annually and nymphs of the first generation usually cause the most injuries. Adults of this generation in late spring migrate from apple to sunflower and mullein. The pest produce two generations on these hosts and fly back to apple tree in fall. The insect overwinters as eggs beneath the bark of young apple branches.

Persistence toxicity time of nine commonly used insecticides against Sunn pest and other cereal pests was evaluated using IOBC method and T. grandis as a biotest. The experiment was carried out on pesticide - treated vine leaves as contact surface. Results indicated that trichlorfon and pirimicarb with PTT 5o of less than 10 days are the least persistent. Diazinon, fenestration and phosalone had PTT50 11.90, 13.05 and 15.58 days respectively. Pyrethroids were the most persistent compounds among the insecticides tested with PTT50 of 17.98 and 19.85 days for deltamethrin and lambda - cyhalothrin respectively. Except for pyrethroids three – days - old deposit of tested insecticides was highly toxic to adult wasps. Statistical analysis showed that parasitism percentages of survived wasps tTom 10 days old deposit of pyrethroids except lambda - cyhalothrin were in the same group. Results of these studies indicate that the first 10 days following spraying is very crucial period for parasitic activity of T. grandis.

Indian meal moth, Plodia interpunctella Hb., a polyphagous, and cosmopolitan species, is widely distributed, throughout Iran and all over the world. When this pest reared under temperature of 27±1 "C and 50-60% relative humidity, the adults mated 24 hours after emergence, the mating was repeated more than once. The female can oviposit 12 hours after mating and their eggs generally hatched in 2.5 days. The number of eggs depend on the diet and feeding quality of larvae. The average number of eggs were 144.7, 123.5 and 111.8, when the larvae fed on pistachio, walnut and almond kernels respectively. The larval diets affected the pupal and adult duration. The mean larval period, when the larvae were fed on pistachio, walnut and almond kernels, were 31.8, 38.08 and 74.38 days respectively, which were significantly (P=0.01) different. The mean pupal period were 8, 8.46 and 15.71 days when larvae, were fed on pistachio, walnut and almond kernel respectively. Moreover the observation showed a significant difference between mean pupal period at I % level of significance, when the larvae fed on almond kernels in comparison to two other diets. The mean life span duration of adults when fed by pistachio, walnut, and almond kernels, were 7, 8.57 and 9.18 days respectively. In contrast to the kind of diets, which has been the source of nutrients for the larvae, they all had 4 to 7 times of ecdysis.

The stem borer also Known as sart borer (Aeolesthes sarta) is the most destructive insect pest of many trees in central and, east Asia, countries and Iran. It has high economic importance in these countries. Distribution pattern and ecological studies on sart longhorn beetle (A. Sarta) was carried out during 1997-2001 in Iran. In this regard we visited different settings of ecosystems including forests, fruit gardens, urban vicinities in many parts of Iran. Infested logs of host trees were brought to laboratory from various localities and adults or larvae of pest were collected for further studying. Furthermore, cerambycid specimens in Forest and Rangeland Arthropod Museum were examined in this respect. The result indicated that the borer is widely distributed in Iran. It was detected on several host trees in east and northeast (Khorasan), Southeast (Systan and Baluchestan), central areas (Tehran, Isfahan) and south (Kohgiloyeh and Boyer Ahmad) of Iran. Host trees included Populus alba, P .nigra, Juglans regia, Salix spp. Ulmus spp. Platanus orientalis, Morus alba, Elaeagnus angustifolia, Alnus subcordata, Robinia sp. and Amygdalus spp. Infestation rate was 40 to 100% on varioushost trees. It should be moted that, alder (Alnus Subcordata) and mountain almond (Amygdalus spp.) are new host record for A. sarta in the world. Furthermore, Morus alba is reported as new host of A. sarta in Iran.