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The common pistachio psylla, Agonoscena pistaciae Burckhardt & Lauterer, 1989 (Hemiptera: Aphalaridae), is a key pest found in pistachio orchards in Iran. This pest has a high potential for developing resistance to insecticides due to its short life cycle and high reproductive potential. Intensive application of insecticides leads to excessive selection pressure followed by resistance to synthetic insecticides in some psylla populations. In this research, effects of four concentrations of three extensively used insecticides (spirotetramat, acetamiprid, and hexaflumuron) on energy resources (like sugar, lipid, glycogen, and protein contents), energy consumption, and cellular energy allocation were investigated in resistant and susceptible populations of the common pistachio psylla in the Kerman province of Iran. Energy resource contents in the susceptible population (133 331.2 mj/insect) were significantly more than in the resistant population (96 253.5 mj/insect), whereas energy consumption in the resistant population (38 630.4 mj energy/h/insect) was higher than in the susceptible population (31 276.8 mj energy/h/insect). Additionally, cellular energy allocation in the resistant population (2 400.9 mj energy/h/insect) was higher than in the susceptible population (2 126.13 mj energy/h/insect). Therefore, stress (especially toxicants) causes variations in metabolism, which influences the growth and reproduction of the pest.

Tetranychus urticae Koch, is a major pest of many plants including greenhouse and field crops in the world. The development of resistance in T. urticae populations to pesticides has motivated the search for alternative control methods to suppress the pest. The control of T. urticae by ozonated water on pepper (Capsicum annuum L.) was tested in greenhouse trials. Ozone at 43 g/m3 concentration with a flow rate of 12.87 g/h ozone was applied as aqueous form at different times (8 am, 2 pm and 8 pm) and different ages of the plant (4, 8 and 12 weeks old) for three exposure times (5, 10 and 15 seconds). The results indicated that in all treatments, T. urticae was susceptible to 43 g/m3 ozone concentration. In all cases, differences in mortality percentage of control and ozone treatments were significant, but differences in the mortality percentage among either time of application or duration of exposure time and ages of plant treatments were not significant. Also, no symptom of injury (chlorosis, necrosis, yellowing, or malformation) was observed for any of the pepper's leaves after aqueous ozone spraying. Based on these results, aqueous ozone can reduce the population density of T. urticae without any visible damage on the pepper leaves. However, more research needs to be done before ozonated water can be deployed commercially as a pesticide.

Solid lipid nanoparticles (SLN) loaded by Ziziphora clinopodioides Lam. were synthesized using the method of high shear homogenization and ultra sound. The lipid phase consisted of percirol ATO5 and campritol 888 (5% w/v). Poloxamer 188 (2.5% w/v) was used as surfactant. Different amount of essential oil (1, 2, 2.5% w/v) were added to SLN. Particle size of solid lipid nanoparticle loaded by essential oil (2.5%) (SLN-EO) was 241.1 nm with poly dispersity index (PDI) of 0.312 and Zeta potential – 22.6 mv. Entrapment efficiency of SLN-EO (2.5%) was 93%. Transmission electron microscopy (TEM) study showed the spherical particles with the size under 100 nm. Based on the results of fumigant toxicity, the LC50 values of SLN-EO and pure oil against Tribolium castaneum were 30.602 and 68.303 µL. L air−1, respectively. These results demonstrated that SLN-EO had higher toxicity effects on red flour beetles. The comparative assessment of persistence indicated SLN-EO formulation remained effective until 14 days, while the pure oil lost its toxicity after the 8th day of application. Chemical composition of Ziziphoraclinopodioides showed that pulegone (51.78%), 1, 8- cineole (8.95%), p- menthone (7.74%) and piperitenone (5.7%) were the major components.

The selection of oviposition sites by aphidophagous insects is complex because of tritrophic interactions among host plant, aphid, and natural enemies. Several factors are known to affect the choice of oviposition site by aphidophagous hoverflies. The decisions of ovipositing females about where to lay their eggs are even more important in insects whose newly hatched offspring have limited dispersal ability, such as most aphidophages. In this study, we focused on the oviposition responses of two generalist aphidophagous syrphids ( Eupeodes luniger and Episyrphus balteatus ) toward host plant–aphid combinations differing in sinigrin content and the presence of intra- and interspecific competitors. The oviposition preference of Eupeodes luniger was significantly influenced in a reverse manner by the presence of intraguild competitors and also by the sinigrin content of host plants (P Episyrphus balteatus was greater on aphids with relatively low levels of sinigrin. Our findings help in understanding the factors governing the oviposition responses of aphidophagous predators.

1. Plant secondary metabolites can govern prey–predator interactions by altering the diet breadth of predators and sometimes provide an ecological refuge to prey. Brassicaceae plants and their specialist pests can be used as a model system for understanding the role of chemically mediated effects restricting the diet breadth of natural enemies, and consequently the occurrence of enemy-free space for the specialist pest. 2. The objective of the present study was to test the performance of the generalist predator Episyrphus balteatus De Geer (Diptera: Syrphidae) fed on the specialist herbivore Brevicoryne brassicae L.(Homoptera: Aphididae), reared on two different brassica species: black mustard (Brassica nigra), a wild species with high levels of sinigrin; and canola (Brassica napus), a cultivated species without sinigrin. 3. The preference and performance of the predator and the performance of the prey were measured. Sinigrin was quantified by high-performance liquid chromatography in both leaf samples and aphids reared on the two host plants. 4. The cabbage aphid performed better on canola than on black mustard. The performance of the predator on this aphid when reared on canola was clearly better than when reared on black mustard. Females had a higher overall preference for cabbage aphids reared on canola than on black mustard. 5. The ability of aphids reared on plants with high glucosinolate content to reduce the performance of their generalist predators indicates that the presence of B. nigra may provide enemy-free space for the cabbage aphid from its predator, a concept that has useful application in the context of biological control for agricultural systems.

Objective To determine distribution of rodents' arthropods and estimate infestation parameters of fleas, mites, ticks, and lice associated with wild rodents in Mashhad and its vicinity, Iran. Methods The rodents were captured using live trap from April 2013 to December 2014 in Mashhad and vicinity, Khorasan Razavi, Iran. The ectoparasites were collected from body surface of rodents using brushing, combing or forceps and preserved in 70% ethanol. The samples were examined by stereomicroscope and classified into four groups including fleas, mites, ticks, and lice. Dark specimens were made more transparent by soaking in potassium hydroxide or Nesbitt's fluid (where appropriate). The specimens were mounted on glass slides using Hoyer's medium. Ectoparasitic identification was done based on the available keys and confirmed by qualified taxonomists. Results A total of 197 rodents were trapped representing 11 species which belong to the family Muridae (7 species), Cricetidae (3 species) and Sciuridae (1 species). The most common captured rodent species was Mus musculus (13.19%) and the least was Apodemus witherbeyi (6.59%). In total 783 ectoparasites related to 3 orders, 8 families, 10 genera and 15 species were collected. The infestation rates by fleas, mites, ticks, and lice on the rodents were 18.78%, 22.84%, 18.78% and 10.15 %, respectively. Conclusions Overall infestation rate was 42.13 % (83 out of 197 rodents). The most and least frequency of ectoparasites belonged to mites (50.44%) and lice (14.04%), respectively. The results suggested that the prevalence of ectoparasites could be influenced by rodent host species. Monitoring the rodent population and their ectoparasites is recommended to facilitate arthropod-borne disease control programs.

Aphidiinae (Braconidae: Aphidiinae) is a subfamily of endoparasitic wasps specialized in parasitizing aphids. Although, to date, different methods have been used to measure parasitism level, obtaining an accurate estimate remains challenging due to several limiting factors. This study was set to: 1) Compare efficiency of conventional and molecular-based methods in estimating parasitism level of the pomegranate aphid Aphis punicae (Passerini; Hemiptera: Aphididae), and 2) Estimate seasonal activity of the Aphidiinae parasitoids of the pomegranate aphid. The molecular approach (polymerase chain reaction [PCR]) detected the presence of three main parasitoids Lysiphlebus fabarum (Marshal; Hymenoptra: Braconidae), Binodoxys angelicae (Haliday; Hymenoptra: Braconidae), and Ephedrus persicae (Frogatt; Hymenoptra: Braconidae). The presence of hyperparasitoid and aphid DNAs did not interfere with the outcome, indicating specificity of the selected primers. Minimum concentrations of DNA needed for successful amplifications were 16.33, 28.65, and 22.65 ng µl−1, for L. fabarum, B. angelicae, and E. persicae, respectively. The level of parasitism was significantly higher in spring (28.42%) than both summer and fall; parasitism level during summer (11.89%) and fall (5.86%) formed a homogeneous statistical subset. Although the overall level of parasitism estimated by PCR (22.7%) was more than twofold higher than those estimated by a conventional counting method (10.5%), there was a strong positive correlation between the two approaches. Provided the potential limitations of either method, simultaneous use of both methods was recommended for an objective estimate of the effectiveness of the Aphidiinae parasitoids as biological control agents of A. punicae.

The common pistachio psylla, Agonoscena pistaciae Burckhardt and Lauterer is a key pest throughout all pistachio producing regions of Iran. Pest management depends primarily on the application of chemical insecticides. The lack of compatibility between natural enemies and pesticides is the main concern to ecologists in the integrated management of psylla. The susceptibility of the fifth instar nymphs of A. pistaciae from five populations of the Kerman province and third instar larvae of the lady beetle species, Oenopia conglobata L., were examined against three commonly used insecticides: acetamiprid, spirotetramat and hexaflumuron, using the spraying tower method. Probit regression analysis was conducted on mortality data at various insecticide concentrations using the POLO-PLUS program to estimate LC50 values. Resistance ratio data revealed that usage of pesticides has led to resistance in the psylla population of Rafsanjan. The results showed that the Rafsanjan psylla population (with LC50 values of 40.55, 43.65 and 95.10 mg a.i. L-1, for acetamiprid, spirotetramat and hexaflumuron, respectively) was the most resistant and the Anar population (with LC50 values of 11.92, 24.13 and 81.06 mg a.i. L-1 for acetamiprid, spirotetramat and hexaflumuron, respectively) was the most susceptible based on the LC50 ratios of insecticides. The LC50 values of acetamiprid, spirotetramat and hexaflumuron for the coccinellid predator O. conglobata in the Rafsanjan population were estimated to be 8.76, 5218.33 and 2268.81 mg a.i. L-1, respectively. The predator was more susceptible to acetamiprid and more tolerant to spirotetramat and hexaflumuron than the psylla A. pistaciae.

Parasitoids play the positive role in aphids control management by keeping the population of aphids below the economic threshold. The pomegranate aphid, Aphis punicae is attacked by several parasitoids which mostly belong to Aphidiinae subfamily. The identification of parasitoids and hyperparasitoids is problematic due to their small size and ambiguous morphological characteristics. The analysis of molecular data of DNA sequences has been suggested as a complementary approach to the classical methods to identify biocontrol agents. In the present study, active parasitoids and hyperparasitoids of the pomegranate aphid collected from Razavi Khorasan province were identified using morphological characters and analysis of two gene sequences including COI and 28S. Phylogenetic analysis was performed using Maximum parsimony and Bayesian methods. The identified parasitoids were Binodoxys angelicae, Lysiphlebus fabarum, Ephedrus persicae, and the hyperparasitoids were Syrphophagus aphidivorus, Alloxysta sp. and Pachyneuron sp. We demonstrated that the mitochondrial COI gene was superior for the identification of these insects compared to the nuclear 28S (D2- region) and that it was compatible with morphological studies. This is the first study on molecular identification of the parasitoids and hyperparasitoids on pomegranate aphids in Iran, Parazitoidler yaprak bitleri populasyonunu ekonomik eşiğin altında tutarak kontrol yönetiminde olumlu bir rol oynar. Nar yaprakbiti, (Aphis punicae) çoğunlukla Aphidiinae alt familyasına ait çeşitli parazitoitler tarafından saldırıya uğramaktadır. Parazitoitleri ve hiperparazitoidlerin tanımlanması, küçük boyutları ve belirsiz morfolojik özellikleri nedeniyle sorunludur. DNA dizilerinin moleküler veri analizi, biyokontrol ajanlarını tanımlamak için klasik yöntemlere tamamlayıcı bir yaklaşım olarak önerilmiştir. Bu çalışmada, Razavi Horasan ilinden toplanan nar yaprak bitinin aktif parazitoitleri ve hiperparazitoidleri morfolojik karakterler kullanılarak ve iki gen dizisinin COI ve 28S’in analizi de dahil olmak üzere tanımlanmıştır. Filogenetik analiz maksimum parsimoni Bayesian yöntemleri kullanılarak gerçekleştirilmiştir. Tanımlanan parazitoidler Binodoxys angelicae, Lysiphlebus fabarum, Ephedrus persicae, hiperparazitoidler Syrphophagus aphidivorus, Alloxysta sp. ve Pachyneuron sp.’dir. Mitokondriyal COI geninin bu böceklerin tanımlanması için Nükleer 28S’e göre (D2 bölge) üstün olduğu ve morfolojik çalışmalar ile uyumlu olduğu tespit edilmiştir. Bu çalışma, İran'da nar yaprakbiti parazitoit ve hiperparazitoidlerinin moleküler tanımlaması açısından ilk çalışmadır

In the present study, the effects of volatile components of Citrus paradisi, C. aurantium, C. limonium and C. sinensis peel essential oils were investigated on the cowpea adult bruchid, Callosobruchus maculatus (F.). The oils were extracted from the fruit peels using hydrodistillation. The results indicated that the citrus oils had high fumigant activity against adult beetles. The mortality of 1-2 day-old adults increased with concentration and exposure time from 3 to 24 h. The oil of C. paradisi was more effective than those of C. aurantium and C. limonium (The LC50 values were 125, 145 and 235 microl L(-1) at 24 h exposure, respectively). The oil of C. sinensis proved to be least toxic (LC50 = 269 microl L(-1). The results suggested that citrus peel oils can be used as potential control measure against cowpea beetles.