---

Searching efficiency and handling time are two major components of functional response and are usually used to evaluate effectiveness of natural enemies. The effect of different foraging periods on the functional response of larval Aphidoletes aphidimyza (Rondani) (Dip.: Cecidomyiidae) feeding on third instar nymphs of Aphis craccivora was studied. The experiment was conducted in terms of time-specific (1, 2, 4, 6,12, 24 h.) functional response to varying densities (5, 10, 20, 40, 60 and 80) of third instar nymphs of A.craccivora at 23 ± 1 °C, 70 ± 5% of R.H., and a photoperiod of 16:8 h (L: D). Parameter estimates for logistic regressions showed a type II functional response for 4 day-old larvae of the predator at different foraging periods to varying densities of A. craccivora. The estimated searching efficiency (a') and handling times (T_h), varied with foraging periods. The searching efficiency showed a decreasing trend as the foraging periods increased. The estimated maximum rates of predation (T/T_h) for the 4-day old larvae were directly related to the foraging periods increase but handling times (T_h), showed a decelerating trend. In conclusion it was found that searching efficiency was a variable parameter in different foraging periods of A. aphidimyza and was lowest at the foraging periods of 24 h. It was also suggested that A. aphidimyza with type II functional response in all foraging periods, could be considered as a highly effective biological agent in suppressing A. craccivora population.    

---

Angoumois grain moth, Sitotroga cerealella (Olivier) is one of the most important pests of stored products and known as factitious host for mass rearing of insect natural enemies. Effect of four commercial barely varieties including Fajr 30, Behrokh, Nik and Yousef on life table parameters of S. cerealella was determined at 26 ± 2 °C, 65 ± 5% RH and a photoperiod of 12:12 h (L: D). Data were analyzed based on the age-stage, two-sex life table theory. The results revealed that there were significant differences among various barely varieties regarding the developmental times, adult longevity and fecundity of S. cerealella. The longest developmental time (56.72 ± 0.29 days) was observed on Yousef. The longest and shortest male longevity were obtained on Behrokh (6.77 ± 0.27 days) and Yousef (5.79 ± 0.16 days). Moreover, female longevity ranged from 6.20 ± 0.18 to 7.23 ± 0.24 days on Yousef and Behrokh, respectively. The highest values of intrinsic rate of increase (r) were estimated 0.0719 ± 0.004 and 0.0717 ± 0.003 day^-1 on Fajr 30 and Behrokh, respectively and the lowest values were 0.0539 ± 0.004 and 0.0542 ± 0.003 day^-1 on Nik and Yousef, respectively. The longest generation time (T) was observed on Yousef. Furthermore, peaks of reproductive value occurred at ages of 45, 49, 48 and 53 days when reared on Fajr 30, Behrokh, Nik and Yousef, respectively. It can be concluded that Fajr 30 and Behrokh can be used for mass rearing programs of S. cerealella as an alternative host for natural enemies.

---

Citrus swallow tail butterfly, Papilio demoleus L. is a pest of citrus in many parts of the world. We examined the effect of four different citrus hosts including Citrus sinensis (L.) (Tarocco and Valencia) Citrus limon (L.) (Eureka), and Citrus paradisi Macfad. (Shambarg) on its life table parameters and biological characteristics at 24 ± 1 °C, 75 ± 5% RH and a photoperiod of 16: 8 h (L: D). The developmental time of immature stages was longest onC. sinensis (Tarocco) (12.3 ± SE days).The intrinsic rate of natural increase was significantly affected by variouscitrus, being the highest on C. sinensis (Tarocco) (0.099 day^-1) and lowest on C. sinensis (Valencia) (0.011 day^-1).The highest and lowest finite rates of increase were observed onC. sinensis(Tarocco) 1.10 andC. sinensis(Valencia)1.01, respectively.The highest gross reproductive rate and the lowest mean generation time were observed on C. sinensis (Tarocco) and C. sinensis. (Valencia), respectively. The findings indicated that C. sinensis (Tarocco) appeared to be the most susceptible host to P. demoleus among the tested varieties. The results of this and similar studies in the future on other hosts may be considered as a basis for finding resistant host/hosts in monitoring this pest.

---

---

Safflower (Carthamus tinctorius L.) is an important oilseed crop in Iran and many other countries around the world. Safflower fly, Acanthiophilus helianthi Rossi is one of the main limiting agents to expand the production area of the crop in different countries and the most major pests of safflower in Iran. In this research, the influence of 10 safflower genotypes on biology and population parameters of A. helianthi was evaluated under the laboratory conditions at 25±1°C, 65±5% relative humidity, and a photoperiod of 16:8 (L: D) hours. The shortest and longest total developmental time were recorded in Mexico 37 (16.85±0.31) and Goldasht (21.76±0.59), respectively. The intrinsic rate of natural increase (r) ranged from 0.129 to 0.186 (day^-1), which was lowest on Goldasht and highest in Mexico 37. The net reproductive rate (R₀) ranged from 50.809 to 125.846 offspring on different genotypes. The values of finite rate of increase (λ) and mean generation time (T) on different safflower genotypes ranged from 1.138 to 1.205 day^-1 and 25.778 to 30.421 days, respectively. The results demonstrated that Goldasht, Line 411, and KW2 genotypes were less suitable host plants, suggesting that they are more resistant to A. helianthi than the other genotypes, have high yield, and could have the potential for using in Integrated Pest Management program (IPM) of A. helianthi in safflower fields.