فهرست مطالب f. yarahmadi

Among the different pests of wheat, cereal aphids are considered important pests that cause economic damage at high densities. Induced resistance by using some chemical and natural products can be an effective tool to control these pests in an integrated pest management (IPM) program. In this study, the effects of some potential resistance inducers, salicylic acid (SA), calcium silicate (CaSi), potassium silicate (PSi) and tea aquatic extract, on some cereal aphid populations were investigated under field conditions. Based on the results, almost no significant difference was observed between the potential resistance inducer treatments and the control on most sampling dates. The obtained results showed that there was no significant difference between the yield parameters, e.g., wheat spike length, spike numbers/m2, seed numbers/m2, seed numbers/spike, 1000 seed weight, wheat plant length, total spike weight/m2 and total seed weight/ha, between the potential resistant inducer treatments and the control. The analysis of defensive compounds like hydrogen peroxide and flavonoids, along with the activities of defensive enzymes peroxidase and catalase showed that there is no significant difference in the flavonoid and peroxide contents of plants treated with CaSi, PSi, SA, and tea extract. The peroxidase activity assay also indicated no significant difference among the treatments. Furthermore, although plants treated with PSi showed the lowest catalase activity compared to the other treatments, there was no significant difference in peroxidase activities among plants treated with the resistance inducers and control. Therefore, the study indicated that resistance inducers are not significantly effective in the pest control.

The cotton mealybug, Phenacoccus solenopsis Tinsley, is a potential pest that threatens green landscape in Ahvaz. In this study, the short-term and long-term effects of various insecticides (imidacloprid, diazinon, spinosad, Palizin®, and azadirachtin) on the populations of cotton mealybugs and predatory ladybird beetles, Nephus sp. and Hyperaspis sp., as well as on the parasitism rate of cotton mealybug by Aenasius bambawalei Hayat, were investigated under field conditions. The results of the bioassay at 24 h after treatment showed that imidacloprid (84.6%), diazinon (84.1%), and Palizin® (77.4%) significantly reduced the population of mealybugs compared to the control. The decrease effect of azadirachtin on the population density of cotton mealybugs 24 h after treatment was not significant (38.1% compared to the control). Furthermore, diazinin and azadirachtin had the greatest negative impacts (100% reduction compared to the control), and Palizin® had the least toxicity to ladybirds, with no significant difference compared to the control treatment. The long-term effects of the tested insecticides showed that, compared with the other treatments, imidacloprid and Palizin® had significant effects on reducing the pest population. Palizin® and azadirachtin had the least effect on the parasitism activity of Aenasius bambawalei. Both imidacloprid and insecticidal soap were more effective at reducing the P. solenopsis population than were the other treatments, but due to the greater negative effect of imidacloprid than of insecticidal soap on natural enemies and the limitation of using insecticides in green landspaces, insecticide soap is suggested for use in IPM programs for this pest.

Microcerotermes diversus Silvestri, is an important termite in Khuzestan province with a broad range of foraging. In recent years, control of underground termites has been more based on the application of chemicals which has increased pest insecticide resistance. In this study, the resistance of different populations of termites to chlorpyrifos was investigated using estimated LC50 and measuring the activity of two acetylcholinesterase (AChE) and glutathione-s-transferase enzymes. Four populations of M. diversus with different histories of organophosphorus insecticide spraying were studied. Populations A (Am Altamir1), B (Am Altamir2), and C (Mollasani) were collected from date palm groves with 30 and 10-year histories of organophosphorus insecticide spraying, as well as without spraying history, respectively. Population D (Ramin University) was collected from orange trees, three weeks after spraying with chlorpyrifos. The bioassay results showed that the highest and lowest LC50 values were observed in populations A and C, respectively. Moreover, the activity of AChE using acetylthiocholine iodide, propionylthiocholine iodide, and butyrylthiocholine iodide substrates was higher in the populations with chlorpyrifos spraying history, with the highest activity in population A. It was also demonstrated that the AChE activity with acetylthiocholine iodide substrate was higher than the activity of this enzyme with butyrylthiocholine iodide and the propionyl choline substrates in the populations with 30 and 10-year history of spraying. The Michaelis constant (Km) and maximum velocity (Vmax) values of AChE as two important kinetic factors, indicated the highest affinity of this enzyme to the substrate in population A.

The cotton mealybug, Phenacoccus solenopsis Tinsely (Hemiptera: Pseudococcidae), is an important pest of many plants in agroecosystems and urban green landscapes. In this study, potential of three isolates of Akanthomyces lecanii, isolates PAL6, PAL7, and PAL8, and an isolate of A. muscarius, isolate GAM5, to microbial biocontrol of this pest on Coleus blumei, as the pest host plant, were investigated under greenhouse conditions. The infested host plants to five last instar nymphs were treated using different conidial suspension concentrations (104,105, 106, 107, and 108 conidia/mL) of each isolate and the mealybug mortalities were recorded every day, for eight days. The mortalities were varied from 14.3% (isolate PAL7) to 1.79% (isolate PAL8). The highest mortality was observed in concentration of 108 conidia/mL of the pathogens. The highest mortality caused by the pathogens was recorded six days after treatment. Totally, conidial suspension concentration of 108 conidia/mL from A. lecanii PAL7 was the best candidate for microbial biocontrol of the mealybug among the pathogens causing 56.17% mortality in the pest population six days after treatment. The results can be used for developing microbial biocontrol of the cotton mealybug especially in greenhouse conditions.

The Black bean aphid (BBA), Aphis fabae Scopoli (Hemiptera: Aphididae), is an important pest of agricultural and ornamental plants. Entomopathogenic fungi are important factors in the microbiological control of pests that are considered a good alternative for chemical insecticides. Isolation of novel potential IPF and evaluation of their efficacy against pests are primary steps for achieving a successful microbiological control program. In this study, the efficacies of three Iranian isolates of Akanthomyces lecanii (PAL6, PAL7, and PAL8) and an Iranian isolate of A. muscarius (GAM5) which had been isolated from two hemipteran pests, Pulvinaria aurantii Cock. and Aphis gossypii Glover, respectively, in citrus orchards of west Mazandaran (North of Iran), were evaluated against BBA.

Mortalities of the BBA nymphs and adults caused by different conidial concentrations (104, 105, 106, 107 108 conidia/ mL) of each fungal isolate during other days after treatment (DAT), 1–7 DAT, were determined under laboratory conditions.

All isolates were pathogenic to the aphid causing about 25% mortality. The efficiency of the isolates was not significantly different among the aphid life stages. When the isolate concentrations (up to 55%) and DAT (up to 53.13 times) increased, their effects increased significantly. The highest and lowest mortality rates were observed at concentrations 108 (12.83%) and 104 (5.86%) conidia/ mL, respectively. The highest effectiveness was recorded in seven DAT for all isolates, 15.14% mortality. At one DAT, the isolates caused about 1% mortality in the aphid population with the lowest effectiveness. The highest mortalities were observed for GAM and PAL7 isolates at six DAT, i.e., 16.83 and 16.67%, respectively. Furthermore, the lowest effectiveness was recorded for the isolates GAM and PAL7, at one DAT (<0.1% mortality), respectively.

The isolates had some potentials for microbiological control of the BBA. Time and conidial concentrations, are the critical factors determining the efficacies of the entomopathogenic fungi. The highest effectiveness can be achieved before six DATs. When the conidial concentrations increased, the obtained mortality by the isolates was enhanced. Due to the relatively low efficacies of the EPF and a lag time for getting sufficient mortality, integrated applications of the entomopathogenic fungi with other compatible control agents with faster effects such as biorational insecticides are recommended. However, the laboratory results should be supported with field or semi-field studies before recommending applications of the entomopathogenic fungi against the BBA aphids in greenhouse or field crops.

=Brand is a name, term, design, symbol, or a combination of them, intended to identify the goods or services of one seller or group of sellers and to differentiate them from competitors. product repurchase, Customer satisfying and finally Branding issues have turned to be the foremost important concern for many organizations. This is because a successful brand provides the firm with opportunities to utilize its core competences and differentiated organizational structure to secure a position in consumers’ minds. The purpose of this research is survey of impact of brand equity on Repurchase of dates with the mediating role of customer satisfaction in Khuzestan Province. This research is practical and descriptive-correlation and case study that did about Khuzestan Province dates in 2021. To do this research a sample was chosen which includes 210 people of the employees, businessman, agricultures and customers of Khuzestan Province dates. In this research 3 hypothesis were set forth. To explore the research hypothesizes used the Likert Scale questionnaire 5 choice. After completing the research and doing descriptive and (Linear Multiple regression) inferential statistic's tests, the research hypothesizes has been proved. Results show that has significant positive effect of brand equity on Repurchase of dates with the mediating role of customer satisfaction.

The parasitoid wasp, Telenomus busseolae Gahan (Hymenoptera: Plathygasteridae), has been extensively used to biological control of Sesamia cretica Led. (Hymenoptera: Plathygasteridae) in Khuzestan province, Iran. Due to dramatically population growth of S. cretica, the parasitoid wasp has not effectively controlled the pest during some seasons. Previous studies implicated physical control of S. cretica can be achieved using ultrasound. In this investigation, the effectivness of ultrasound on S. cretica to parasitism ability, sex ratio and distribution pattern of T. busseolae were evaluated under laboratory conditions. Results indicated that the ultrasound at frequency 37.5 KHz and Sin (X) wave shape has not significant effect on the wasp parasitism during various activity days. The parasitoid wasp treatment by the ultrasound did not significantly influenced the wasp sex ratio during 4 generations. Investigation on distribution pattern of exposed wasp showed that the wasp has random pattern, similar to control. The study indicated that T. busseolae cannot distinguish the ultrasound. Therefore, physical control of S. cretica using the ultrasound (at frequency 37.5 KHz and Sin (x) wave shape) has not any antagonistic effect to biological control by T. busseolae and the compatible strategies can be applied in integrated control of S. cretica.

The hemipteran, Macrolophus pygmaeus Rumber, is an effective biocontrol agent against many crop pests including tomato leaf miner, Tuta absoluta Meyrick. Sublethal effects of azadirachtin (Neem Azal®), indoxacarb (Avaunt®), and emamectin benzoate+lufenuron (Proclim Fit®) were studied on biological characteristics and functional response of the predatory bug in laboratory conditions at 25±1°C, 6 ±5% RH, and a photoperiod of 16:8 hour (L:D). For this purpose, females of the predatory bug were exposed to sublethal residues (10% of field concentration) of the insecticides. Two-sex life table and Rogerchr('39')s model were used to investigate effects of the insecticides on biological parameters and functional response of the predator, respectively. Results indicated that sublethal residues of indoxacarb and azadirachtin had the highest and lowest side effects on life table parameters of M. pygmaeus. Whereas azadirachtin has no significant effects on the bug biological parameters, total fecundity and longevity of the bug in indoxacarb treatment were significantly lower (14.6%) and higher (6.9%) than the control. The predator showed type III functional response. The type of functional response was not affected by the insecticide residues. However, the coefficient of attack rate (b) for the indoxacarb treatment (0.1521) was significantly lower than for other treatments. However, there was no significant difference between the handling Times (Th) of the treatments. In conclusion, the experiments proved that azadirachtin is a low risk insecticide to M. pygmaeus, which can be integrated with biological control by the predator.