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In this research, functional responses of Amblyseius swirskii Athias-Henriot preying on different Tetranychus urticae Koch nymphal densities (2, 4, 8, 16, 32, 64, and 128) were studied at eight constant temperatures (15, 20, 25, 27.5, 30, 32.5, 35 and 37.5°C) in a circular Petri dish (3-cm diameter × 1-cm height) under lab conditions. At all temperatures, the logistic regression showed a type II functional response. A nonlinear relationship was found between temperature and attack rate and the reciprocal of handling time. The reciprocal of handling time decreased exponentially with increasing temperature. In contrast, the attack rate grew rapidly with increasing temperatures up to an optimum, showing a decreasing trend at higher temperatures. In order to quantify the functional response of A. swirskii over a broad range of temperatures and to gain a better estimation of attack rate and handling time, a temperature-settled functional response equation was suited to our data. Our model showed that the number of prey consumed increased with rising prey density. Also, the predation rates increased with increasing temperatures but decreased at extremely high temperatures. Based on our model, the predation rate begins at the lower temperature threshold (11.73°C) and reaches its peak at upper temperature threshold (29.43°C). The coefficient of determination (R2) of the random predator model was 0.99 for all temperatures. The capability of A. swirskii to search and consume T. urticae over a wide range of temperatures makes it a good agent for natural control of T. urticae in greenhouses.

In this study, temperature-dependent oviposition model of Amblyseius swirskii Athias-Henriot fed by Tetranychus urticae Koch as prey was developed. In order to obtain data for the model, the longevity, fecundity and survivorship of adult females of A. swirskii were recorded at seven different temperatures (15, 20, 25, 27.5, 30, 32.5 and 35 °C) all at 60±5% RH and a photoperiod of 16:8h (L; D) in growth chamber. The longevity of females decreased with increasing temperature; the maximum at 15°C (84±3.24 days) and the minimum at 32.5°C (22.48±0.31 days). The female adult developmental rates (1/median longevity) was described by Sharpe and DeMichele model (r2=0.99). The highest and the lowest fecundity were observed at 25°C (22.63±0.76 eggs/female) and 15°C (9.4±0.67 eggs/female), respectively. The oviposition model comprised of three functions: temperature-dependent fecundity, age-specific cumulative oviposition rate and age-specific survival rate. The best model of temperature-dependent fecundity was described by a non-linear equation (extreme value function) (r2=0.98). Similarly, the best model of age-specific cumulative oviposition was described by the two-parameter Weibull function (r2=0.94). Eventually, the best model of age-specific survival rate was described by sigmoid function (r2=0.97). Amblyseius swirskii has ability to control pests such as thrips, whiteflies and two-spotted spider mites and can grow even in low temperatures. Therefore, this mite can be active at the beginning of spring season. Temperature-dependent oviposition model of A. swirskii can determine optimal temperature for mass-rearing and predict seasonal population dynamic of this predatory mite in greenhouses. Finally, the greenhouse data can validate this model in future.

In this study, developmental time of Amblyseius swirskii Athias-Henriot feeding on immature stages of Tetranychus urticae Koch was evaluated at eight constant temperatures (15, 20, 25, 27.5, 30, 32.5, 35, and 37.5 °C) providing 60±5% RH and a photoperiod of 16 L: 8 D. Duration of the egg to adult developmental time decreased sharply with increasing temperature, except at 37.5°C. To describe the developmental rate of A. swirskii as a function of temperature, one linear and 9 nonlinear models (Logan-6, Logan-10, Lactin-1, Lactin-2, Briere-1, Briere-2, Analytis-3, Polynomial, and Equation-16) were fitted. The lower temperature threshold (T0) and the thermal constant (K) were estimated by the linear model for the total immature stage as 7.90 °C and 140.85 DD, respectively. Based on the Akaike Information Criterion (AIC) and R2adj, Polynomial, Analytis-3, Analytis-3, Logan-10 and Briere-2 were the best models for eggs, larvae, protonymphs, deutonymphs and total immature stages of A. swirskii, respectively. Our findings showed that development and predation of A. swirskii occurs in a wide range of temperatures. Therefore, this predatory mite could be applied in control of T. urticae in different weather conditions.

The development of the Mediterranean flour moth, Ephestia kuehniella (Zeller), was evaluated at 10, 15, 17.5, 20, 22.5, 25, 27.5, 30 and 32.5°C with no lighting. None successfully completed development at 10 and 32.5°C. The total development time from egg to adult emergence was 164, 140, 98, 76, 61, 62 and 50 days, respectively, at the remaining temperatures. The developmental rate of E. kuehniella was described by the common linear model and six non-linear models. The lower temperature threshold for the immature stages and the thermal constant for E. kuehniella were 9°C and 1111 degree-days (DD) to complete development from egg to newly emerged adult. Non-linear models estimated the lower and upper thermal thresholds (Tmin and Tmax) and optimal temperature (Topt). The values of Tmax calculated by three nonlinear models ranged from 34°C to 46°C; Topt for each stage of development varied from 24 and 31°C, consistent with the temperature (30°C) at which the most rapid development occurred. Information on the threshold temperatures for development and thermal requirements can be utilized to predict E. kuehniella population dynamics and phenology and to evaluate optimal temperature conditions for mass rearing in stored products.

In this study, we examined the fecundity, survival, and adult longevity of Ephestia kuehniella (Zeller) at different temperatures (15, 17.5, 20, 22.5, 25, 27.5, and 30 °C), and developed a model of oviposition. The fecundity, survival, and adult longevity of E. kuehniella were affected by temperature. Longevity reduced from 15.7 d at 15 °C to 8.79 d at 30 °C. Total fecundity was lowest (160.54 eggs) at 30 °C and highest (351.75 eggs) at 25 °C. The relationship between temperature and total fecundity was described by a nonlinear function. Cumulative age-specific egg laying fitted well to the two-parameter Weibull equation and survival of adults fitted well to a reverse logistic curve. These three temperature-dependent attributes (age-specific cumulative egg laying, temperature-dependent total fecundity, and age-specific survival rate) were integrated into a model of oviposition. Simulation of oviposition using the model has the potential to be useful for predicting patterns of occurrence of E. kuehniella egg populations in stores.

Sunn Pest, Eurygaster integriceps Puton (Hemiptera: Scutelleridae), is the most serious pest of wheat in West and Central Asia. Following harvest, the pest migrates from wheat fields to high elevations to escape high summer temperatures and, the following spring, moves back to the fields. In this work, Sunn Pest populations were monitored in 21 overwintering sites located in seven provinces (with 800–2500 m elevation) in Iran. Litter samples were taken twice in each site, once in July–November 2002 and again in March 2003. At each site 60 Artemesia sp. bushes were selected at random and litter from each bush was collected and the number of live male and female adult Sunn Pest counted. More Sunn Pests were collected in higher elevations in the first sampling. Golestan (893 m), Kermanshah (1583 m), and Qazvin (1675 m), located in valleys and surrounded by mountainous areas, had

The ubiquitous generalist predator Andrallus spinidens (F.) is found in North Iran, which is dominantly cultivated with rice plants. Live and frozen larvae of Galleria mellonella L. and Ephestia kuehniella Zeller were offered to A. spinidens in order to assess their effects on reproductive performance. Predators consuming either live or frozen larvae of G. mellonella developed and weighed similarly, but those fed on live or frozen larvae of E. kuehniella had significantly different developmental times and body weights. Predators feeding on live larvae of E. kuehniella weighed more than those fed on corresponding frozen prey. The fecundity and longevity of the predator were affected neither by prey species nor by prey freezing; nevertheless, egg hatchability was mainly affected by prey freezing. Generally, the use of frozen larvae can be recommended when live prey are scarce.

Demography ofHabrobraconhebetor (Say) (Hymenoptera: Braconidae) on two pyralid host species (Galleria mellonella (L.) and Ephestia kuehniella Zeller) (Lepidoptera: Pyralidae) was studied at 28C in the laboratory. Data were analyzed based on an age-stage, two-sex life table, to take both sexes and variable development into consideration. The intrinsic rate of increase (r), Þnite rate of increase (), net reproductive rate (R0), gross reproductive rate (GRR), and mean generation time (T )o fH.hebetor onG.mellonella were 0.1520 d 1 , 1.1640 d 1 , 12.5 offspring, 50.1 offspring, and 16.8 d, respectively. These values were not signiÞcantly different from the values obtained for E. kuehniella, i.e., 0.1375 d 1 , 1.1473 d 1 , 11.9 offspring, 54.9 offspring, and 18.2 d. The life expectancy of anH.hebetor egg was 10.6 d on E. kuehniella and 10.4 d on G. mellonella. On both host species, the maximum reproductive value of female H. hebetor occurred on the 12th day.