The role of blood cells as the main components of the physiological defense of insects has been reported. Blood cells are the first factors of the circulatory system that participate in dealing with all kinds of stress and foreign factors. In the present study, four types of blood cells were identified in the hemolymph of the sugar beet Weevil Lixus incanescens, which include prohemocytes, granulocytes, plasmatocytes and oenocytoids. Plasmotocytes were the largest hemocytes in terms of size, and the abundance of granulocytes and plasmotocytes in third (70 %) and fourth instar larvae (more 75 %) was higher than other cells. These findings are important as the first step in immunological studies of this insect.

A study carried out on cherry Weevil in Bastam and Zirstagh regions of Shahroud district during 1999-2000. Stone fruits production playing an important role in economy of region. Currently the cherry Weevil is the most important insect pest of cherry, sour cherry and other allied species in Shahrood. Adult insects are metalic green or red in colour, having scattered hairs on elytra. Max., Min. and mean length of adult females was 10.4, 12 and 10.7 and those of males 10, 10.6 and 10.1mm respectively. Length of first instar larva was 1-1.5mm and the last instar measured 7.3-11mm with mean of 9.3 mm. The insect showed to hibernate as last instar larvae in mud chambers at the depth of 5-10 mm in the siol. Adults appeared in mid April and their appearance coincided cherry tree bloosoming. They mated several times after feeding on fruit pulp and young leaves. Oviposition period lasted 28-39 days with mean of 32.3 days. The onset of oviposition coincided the completion of petals fall.Females layed only one egg on each fruits. No. of eggs were 29-193 per female with mean of 99.3. Eggs hatched after 3-5 days with mean of 4.2 days. Min., Max. and mean pupal period were 25, 35 and 29.4 days respectively. Longevity of adults males and females were between 35-60 days with mean of 44.3 days under lab. conditions (25±1°C, 40-50% RH). Under field condition eggs hatched after nearly 10 days and 1st instar larvae penetrated into fruits' stones after 24hrs. larval period lasted 18-20 months, thus each generation of this insect completed in two years. The main hosts of cherry Weevil showed to be cherry and sour cherry and subcidiary hosts that tolerate only minor injuries are apricots, peaches, almonds and pulms.

A study was carried out to determine the suitable spraying time for phosalone against alfalfa Weevil, Hypera postica (Gyllenhal) (Col.: Curculionidae), with the least adverse effects on its major parasitoid, Bathyplectes curculionis (Thomson) (Hym.: Ichneumonidae). Plots of 10m2 were sprayed with phosalone (35%) at 3.0 kg/ha, using a knapsack sprayer. The residues of phosalone in parasitoid cocoon and alfalfa foliage were measured at different time intervals after treatment using high performance liquid chromatography. Residues of phosalone on B. curculionis cocoons treated by dipping method were 0.751, 0.466, 0.245, 0.115, 0.075, 0.044 and 0.019 mg/cocoon in 2 hours, 1, 3, 7, 14, 22 and 30 days after treatment, respectively. Results of this experiment revealed that there was no penetration of the insecticide into the cocoon. In fresh foliage, the residues of phosalone were 74.066±6.9, 47.319±2.1, 16.345±1.99 and 3.743±0.33 mg/kg at 2, 4, 7 and 14 days after spraying, respectively. The residue level on foliage at day 7 is critical and this must be considered as the least interval time between the application of the phosalone and the peak of parasitoid population.

Integrated pest management as a way in reduction of pesticide application, environmental pollution and protection of natural enemies of pests, is very important. A 3-year investigation was conducted in 1999-2001 in the Grizeh Agricultural Research Station in Sanandaj to study the effect of microbial pesticides (including Novodor and Bt-Col) and traded pesticides of neem, comparing with Ekamet, using of fire (in the beginning and end of winter and early April) and grazing of farm by sheep, and reciprocal effects of these treatments on population reduction and yield increases were evaluated. The experiment was conducted in the form of factorial with completely randomized design in 4 replicates. The results indicated that grazing of farm caused significant reduction in larvae population but the wet and dry yield had no significant difference with the control. Also, differences were significant (P = 0.01) between levels of the factor B (burning treatment), and field burning in late winter was the best. Differences between the applied insecticides were significant: Novodor and Bt-Col (based on Bt), and Neem plus and Neem azal-F (based on neem) had no significant differences with the control, but Ekamet reduced the pest population and increased the yield significantly.

Extreme use of pesticides on stored grains is hazardous for non-target organisms and result in resistance of the insects to the pesticides, pollution of the environment and etc. Nowadays, nonchemical methods, including biological agents are considered as safe methods to control the stored grain pests. Entomopathogenic nematodes are one of the most important biocontrol agents. A survey was designed to investigate the presence and efficiency of entomopathogenic nematodes in the soils of Kohgiluyeh and Boyer-Ahmad province, Iran. Sixty nine soil samples were collected from different regions of the province in 2010. Steinernema feltiae, S. carpocapsae and Panagrolaimus sp. were isolated. Because of danger in the use of chemical pesticides to protect the stored products, this study was performed to determine the efficiency of S. feltiae on adults of rice Weevil, Sitophilus oryzae (L.), one of the most important pests of stored products. Under laboratory condition, adult insects were received different concentrations of infective juveniles (Ij) (0, 250, 500, 1000 and 2000 per ml) at different temperatures (25, 27.5, 30 and 32.5oC). Insects were placed on a double layered filter paper saturated with 1 ml of IJs suspension in 9 cm petri dishes. Mortality of the insects recorded every 24hrs, for three days. The best result (77.5% mortality) observed after 72 hours of exposure at concentration of 2000 IJs in 30oC.

During the study of oilseed rape pests in Marvdasht area (Fars province), the infested stems of the crop to Weevil eggs and larvae were collected at April 2008. The larvae were reared at laboratory conditions until adult Weevils emerged. The Weevils were identified as cabbage stem Weevil, Ceutorhynchus pallidactylus (Marsham) (= C. quadridens Panzer) (Col.: Curculionidae), and confirmed by Alziar Gabriel. This species has been reported as a pest of oilseed rape in many European countries such as Poland, former Czechoslovakia, Germany, UK, Austria and Switzerland as well as North Africa, America, Canada and Russia (Barari, 2005). Herewith, the species is reported for first time from Iran.

Research was conducted in Yasouj alfalfa fields during years 1997 - 99 to identify the natural enemies and pathogenic agents of the alfalfa Weevil, Hypera postica (Gyll.), (Col.:Curculionidae) and the following species were identified:1-The parasitoid wasp, Anaphes = (Patasson) sp. In the course of investigation, this parasitoid wasp caused a mean of parasitism of 3.1% on the eggs in the alfalfa fields.2-The parasitoid wasp, Bathyplectes sp. Thorn. During 1997 - 99, this parasitoid wasp caused a mean of parasitism 30.5% on the larval instars of the alfalfa Weevil in the alfalfa fields.3-The predatory bug, Geocoris megacephalus. This predatory bug was observed in some alfalfa fields feeding on the first larvae instars of the alfalfa Weevil, but its density was very low. In laboratory rearing each predatory bug consumed an average of 1.1 alfalfa Weevil first instar larval.4-The predatory bug, Nabis sp. This predatory bug was consumed of larval instars of the alfalfa Weevil. The population density of this predator in-the alfalfa fields was low. 5- Chrysoperla carnea The population density of this predator in the alfalfa fields was low prior to June in three years (1997-99), but was increased gradually.6-The lady birds, Coccinella septempunctata L. The population density of this predator in the alfalfa fields in three years was increased gradually from June. The adult and larvae of this predator consumed of eggs and larvae of the alfalfa Weevil.7-The pathogenic fungus, Beauveria bassiana (Bals.). This fungus caused a mean mortality of 38.1% on the overwintering adult alfalfa Weevil in the alfalfa fields. Under the laboratory condition an average of 86% adult, 56% larvae and 38.5% of the pupae were killed by the pathogen after artificial inoculations. It is therefore, recommended to conduct more research on the effectivness of the spore dusting of the B. bassiana into the alfalfa fields after the harvest to control overwintering adults. Also mass rearing and release of the C. carne a in the spring should be investigated as a potential nonchemical control method. After confirmation of the effectiveness of these control measures in the fields studies they can be used in an I.P.M program of the alfalfa Weevil, in the Yasouj region.