The efficacy of Pyradim ® DF with pyraclostrobin+dimetomorf active ingredient was evaluated in comparison with fungicides Captan, Nordox, Mishocap in the control of pistachio Alternaria late blight. The experiment was carried out in Markazi (Zarandieh), Kerman and Semnan in a Randomized Complete Block Design (RCBD) with 8 treatments and 4 replications. Treatments were applied at two stages (before bud swelling and after the petals fall and fruit set). The data were analyzed using SAS software and mean comparison of disease severity and disease incidence percentages were done by Duncan's multiple range test (P =5%). The results showed that Pyradim with dosage of 1 and 0.75 per thousand has a good efficacy in disease control. So that the efficiency of dosage 1g L-1 in reducing the severity of the disease compared to the control without spraying was about 88% in Zarandieh and about 77% in Kerman and Semnan. The efficacy of Pyradim at the dose of 0.75g L-1 in Zarandieh, Kerman and Semnan was about 76%, 72% and 74%, respectively, but the dose of 0.5g L-1 Pyradim was not acceptable and in the three studied areas was between 52 to 55%. Captan fungicide also had acceptable efficacy in controlling pistachio Alternaria late blight disease, so that its efficiency was more than 70% in Kerman and Semnan and 68% in Zarandieh. In contrast, Nordox and Mishocap fungicides did not have good efficiency. Therefore, 0.75g L-1 pyradim is recommended for controlling pistachio Alternaria late blight disease. تفاصيل المقالة

The study was performed to investigate the Aspergillus growth and aflatoxin production in fresh pistachios stored in different packagings. Forty kg of fresh pistachios of the Abbasali cultivar were sampled and kept in different temperature conditions including 4°C and ambient conventional temperatures in plastic baskets or polyethylene plastic bags. Sub-samples were taken at 4 days intervals for 32 days to measure aflatoxin and evaluate the population of Aspergillus section Flavi. Aflatoxins were quantified by HPLC and the fungal population was monitored by dilution series method and AFPA medium. The results showed that on the first day of storage in all conditions the amount of aflatoxin was undetectable. Aflatoxin infection started on the fourth day after storage in the ambient conventional temperature and increased over time. The lowest production of aflatoxin B1 was in the 4°C treatment. Pistachios stored at ambient conventional temperature and packed in plastic baskets showed the highest amount of aflatoxin B1 production. The effect of the treatments on the production of aflatoxin B1 showed that the samples in polyethylene plastic bags at ambient temperature were the highest. The results showed that in the 4°C treatment, the fungal population was significantly less than in ambient temperature treatments. The lowest fungal population was in the 4°C plastic baskets packaged treatment. This treatment was not significantly different from the 4°C polyethylene bag treatment but was significantly different from other treatments (P≤0.01). In general, keeping fresh pistachio at 4°C and suitable plastic is trustworthy. Storage for more than 8 days in the ambient conventional temperature greatly increases the risk of fungal and aflatoxin contamination. تفاصيل المقالة

Aflatoxin is an important fungal contaminant in various crops. The substrate and its compounds are involved in the growth of fungus and the production of toxins. In order to investigate correlation between sugar and lipid content as the major chemical composition of pistachio kernels with Aspergillus flavus growth and aflatoxin production, the total sugar content was extracted by phenol-sulphoric method and estimated by spectrophotometry. The lipid was also extracted by Soxhlet method. A toxigenic A. flavus strain was used for the study of the fungal growth and aflatoxin B1 production. For that, 20 gram of kernels of different pistachio cultivars were inoculated with 1 ml of fungal spore suspension (2×106 spores/ml) in a completely randomized design with three replications. Eight days after inoculation, the average percent of fungal growth and colonization of A. flavus were calculated. The aflatoxin produced in inoculated pistachios was extracted by Best Foods (BF) method and measured by thin layer chromatography (TLC). The results showed that there was no significant difference in the amount of sugar content in different cultivars of pistachios kernel but the amount of total lipid content was different (P≤0.05). Results of statistical analysis showed that there was no significant correlation between sugar content with fungal growth and aflatoxin production in pistachio cultivars as well as lipid percentage and aflatoxin B1 production. Therefore, to find sources of resistance to A. flavus in commercial pistachio cultivars in aflatoxin management programs, these two factors cannot be used as a standard scale of resistance. تفاصيل المقالة

Pistachio is one of the economic nut fruits in Iran. Water limitation is the most restrictive factor for its production. To overcome the water scarcity crisis, introducing drought-tolerant rootstocks is among the crucial breeding strategies. To investigate the drought tolerance of five Qazvin native pistachio genotypes, an experiment was carried out as a factorial experiment in a completely randomized design with four replications in the greenhouse conditions. The factors were pistachio genotypes (Madari, KalKhandan, Kalehbozi, Sefid, and Ghermez) and irrigation regime (normal conditions and drought stress). The highest relative water content under drought irrigation conditions belonged to the Sefid (59.99%), and Ghermez (59.09%) genotypes. The lowest value (54.68%) belonged to the Madari genotype. The highest electrolyte leakage under drought irrigation conditions belonged to the Madari genotype (55.75%). The lowest electrolyte leakage (42.44%) belonged to the Sefid genotype. Under drought stress, the highest amount of chlorophyll a (2.12 mg g-1 fresh weight), total chlorophyll (3.051 mg g-1 fresh weight), and carotenoid (2.38 mg g-1 fresh weight) was observed in Ghermez genotype. In contrast, the highest amount of chlorophyll b (1.34 mg g-1 fresh weight) was observed in the Sefid genotype. The lowest amounts of chlorophyll and carotenoid in the drought stress belonged to the Madari genotype. According to the results, the Ghermez and Sefid genotypes with lower electrolyte leakage and higher relative water content, chlorophyll, carotenoid, and biomass under water stress, were the more drought-tolerant genotypes. Madari and KalKhandan genotypes with higher electrolyte leakage and lower relative leaf water content, chlorophyll, and biomass were the most drought-sensitive genotypes. تفاصيل المقالة

Aflatoxins, are very toxic mixture and having the potential to cause cancer, produce by some the fungi, mostly Aspergillus flavus and Aspergillus parasiticus, during their growth, harvest and storage on crops such as wheat, corn, cottonseed, peanut, pistachio, etc. For appraising the reaction of maize varieties to A. flavus growth and produced aflatoxin, five varieties of maize, namely KSC400, KSC403, KSC600, KSC703, KSC704, were selected. An isolate A. flavus that produce afalatoxin was used for inoculation of maize kernels (as in vitro conditions). In a statistic completely random design with three replications, 10 gr of kernels of selected cultivars were inoculated with 1×106 spores/ml of fungal spore suspension. After eight days, the percentage of fungal growth and the colonization of maize kernels were calculated. The aflatoxin B1 produced in contaminated all maize cultivars were measured with high performance liquid chromatography (HPLC). Statistical analyses showed a significant difference (α=0.05) between the fungal growth percentages and the amount of aflatoxin B1 in the kernels of tested maize cultivars. Also, the results showed that among mentioned varieties, KSC600 was the least susceptible variety to the growth of Aspergillus. The amount of produced aflatoxin B1 was variable among the varieties. KSC600 had the least whereas KSC403 had the highest rate of aflatoxin B1 content. تفاصيل المقالة

Infection of pistachio nuts with Aspergillus flavus and aflatoxin is one of the serious and important threats in the process of production, export, and consumption of pistachios in the world. Aflatoxins are secondary metabolites that are mainly produced by A. flavus and A. parasiticus. Aflatoxins are generally produced before harvesting and under horticultural conditions. Early-splitting pistachios are one of the most significant sources of contamination to aflatoxigenic fungi in the orchard. In the present study, the population density of Aspergillus section Flavi and aflatoxin content were investigated in early-splitting, irregular cracking, and intact pistachios of the Shahpasand cultivar. Sampling was done from the pistachio orchard of Damghan Pistachio Research Station in the first half of August, and pistachio kernel contamination and population density of the fungus were investigated. Pistachio samples were cultured on an AFPA medium using a serial dilution method (completely randomized design with three repetitions). Aspergillus section Flavi colonies were identified and counted and after three days at 28°C and dark. Aflatoxin contents of pistachio kernels were quantified by high-performance liquid chromatography (HPLC) method. The results were statistically analyzed by SPSS statistical software and the means were compared using Duncan's multiple range test. The results showed that the highest and the lowest contamination rates for Aspergillus section Flavi and aflatoxin have belonged to early-splitting and intact nuts, respectively (P≤0.05). The contamination rate in early splitting pistachios is much higher than in irregular cracking and intact kernel pistachios. تفاصيل المقالة

Peach leaf curl disease, caused by Taphrina deformans (Berk.) Tul., is one of the most serious peach diseases, causing quantitative and qualitative damage to crops across Iran each year. In current study, the efficacy of two new fungicides, Badge®WG280 and Barzidox®WP85%, was evaluated in controlling peach leaf curl disease. The experiment was conducted in Golestan, Semnan and North Khorasan using a randomized complete block design with ten treatments and four replications. Treatments included 0.75, 1, and 1.2 ml l-1 of Badge®WG280 (copper hydroxid+copper oxychloride), 2, 4, and 6 g.l-1 of Barzidox®WP85% (copperoxychloride), 2.5 ml l-1 of Nordox®WG75% (copperoxide(, 3 g l-1 of Captan, and controls (with and without water spraying). Treatments were applied at three physiological stages (the first in autumn after the leaves had fallen, the second at the end of March before the bud had swollen, and the third after the petals had dropped). Disease incidence and severity percentage were determined. Duncan's multiple range test was used to compare the mean disease severity and incidence percentages. The results showed that 6g l-1 of Barzidox® had the highest efficacy in reducing disease severity compared to the control in Golestan and Semnan provinces, with 81% and 80% respectively. Furthermore, the best performance of two indicator fungicides, Nordox® and Captan were 73% and 72% in Golestan province and 67% and 68%, in Semnan province, respectively. According to the results, it is concluded that 1.2ml.l-1 of Badge® and 4g.l-1 of Barzidox® have the best efficiency in controlling the peach leaf curl disease. تفاصيل المقالة

The common pistachio psyllid is one of the most important pests of pistachio trees throughout the pistachio-producing regions in Iran. In the present research, the extracts of some medicinal plants were used to study their inhibitory effect on oviposition and population rates of nymphs of common pistachio psyllid. To evaluate the effect of several medicinal herb extracts (Thyme, Eucalyptus, and Chamomile) on the psyllid, an experiment was conducted in a randomized complete block design with four replications. The extracts were sprayed at concentrations of 2.5, 5, and 7.5 per thousand. Sampling was performed in four stages; 3, 7, 14, and 21 days after spraying. The results showed that among different types of plant extracts, thyme extract was the most effective product on the reduction of population rate of eggs and nymphs of the common pistachio psyllid, although the extract of other medicinal plants, eucalyptus and chamomile, were also reduced the rates of egg and nymph. The dose of 7.5 per thousand of all extracts showed a better effect on the number of insect eggs and nymphs. In addition, the results indicated the better effect of these products on the number of insect eggs and nymphs appeared at 14 and 21 days after spraying. تفاصيل المقالة

پسیل معمولی پستهAgonoscena pistaciae یکی از آفات کلیدی و درجه اول در باغ های پسته استان سمنان و بخصوص شهرستان دامغان (به عنوان یکی از قدیمی ترین و مهم ترین مناطق کشت پسته کشور) می باشد. این حشره در تمام مناطق پسته کاری کشور گسترش دارد و سالیانه خسارت قابل توجهی به محصول پسته وارد می کند. هدف از انجام این تحقیق، جمع آوری و دسته بندی دشمنان طبیعی آفت و معرفی گونه های عمدة پسیل خوار با توجه به وفور جمعیت و وسعت پراکنش می باشد. بدین منظور در طی سال های 85 تا 87 چند منطقه مهم پسته کاری در شهرستان دامغان انتخاب و در هر منطقه چند باغ که به پسیل معمولی پسته آلودگی داشت انتخاب گردید. از باغ های آلوده هر ماه یکبار بازدید و نمونه برداری انجام شد. پس از بررسی و شناسایی نمونه ها، جمعیت حشرات شکارگر و زنبورهای پارازیتوئید تخمین زده شد. نتایج نشان داد که در بین کفشدوزک های جمع آوری شده به ترتیب گونه های: Oenopia conglobata contaminata MenteriesوHippodamia variegate Goezeبه ترتیب با 39 و 23 درصد فراوانی، دارای بیشترین جمعیت و تراکم می باشند. همچنین سن شکاری pistaciae Wagner Anthocoris minkiاز زیر خانواده Anthocorinae بر روی درختان پسته منطقه دامغان فعال است و از پوره‌های پسیل پسته تغذیه می‌کند. مشاهدات حاکی از تراکم پایین جمعیت این شکارگر بر روی درختان پسته نواحی مورد بررسی می‌باشد. همچنین گونه های دیگر حشرات شکارگر مانند بالتوری از باغ های پسته جمع آوری شد. زنبور پارازیتوئید Psyllaephagus pistaciaeنیز با جمعیتی متوسط از پوره های مومیائی شده جمع آوری شد. تفاصيل المقالة

شناسایی عوامل زنده خسارت‏زا و کنترل موفق آنها، از چالش‌هاي مهم در تولید محصول پسته مي‏باشد. در این تحقیق جهت بررسی و شناسایی نماتدهای زیان¬آور گیاهی، تعداد ۱۲۶ نمونه خاک و ریشه از مناطق مختلف پسته¬کاری استان سمنان جمع-آوری گردید. پس از انتقال نمونه‏ها به آزمایشگاه، نماتدها به روش الک و سانتریفوژ استخراج، با استفاده از روش تکمیل شده دگریسه تثبیت و به گليسيرين منتقل شدند. سپس از نماتدهاي جدا شده به تفكيك جنس، اسلايدهاي ميكروسكوپي دائم تهيه شد. پس از بررسي‏هاي ميكروسكوپي، مشخصات ريخت¬شناسي و ريخت¬سنجي تعيين و بـا استفاده از منابع معتبر علمي شناسايي انجام گرديد. در اين مطالعه 14 جنس و گونه از نماتدهای زیان‏آور گیاهی شامل: Boleodorus thylactus، Criconemoides sp، Helicotylenchus dihystera ،Helicotylenchus pseudorubustus، Irantylenchus sp، Meloidogyne incognita، Meloidogyne javanica ، Pratylenchus thornei، Tylenchus devanei، Tylenchorhynchus sp، Rotylenchus sp، Zygotylenchus guevarai، Paratylenchus sp، Xiphinema sp شناسايي گرديد. از بین نماتدهای شناسایی¬شده، بیشترین فراوانی جمعیت متعلق به دو گونه M. incognita و M. javanica، از نماتدهای مولد غده بود. در ۳۵ درصد از نمونه¬های جمع¬آوری شده، این دو گونه نماتد وجود داشت. پس از نماتدهای مولد غده، نماتد Z. guevarai دارای بیشترین فراوانی جمعیت در بین نمونه¬ها بود. این نماتد جزء نماتدهای مهاجر داخلی ریشه گیاهان دو¬لپهای گزارش شده است. ولی در این بررسی فقط از خاک جدا گردید. بررسی خسارت‏های ایجاد شده توسط نماتدهای مولد غده و Z. guevarai در باغ‏های پسته، از جمله اولویت¬های تحقیقاتی در استان سمنان است که ضروری است بررسیهای جامع¬تری در رابطه با آنها صورت گیرد.

تفاصيل المقالة

The issue of contamination of pistachios with Aspergillus flavus and aflatoxin is a serious and important threatto the production, export and consumption of pistachios worldwide. Investigating the resistance of pistachio cultivars to A. flavus and its relationship with the physicochemical characteristics of pistachio kernels can be considered as one of the main management strategies to deal address aflatoxin contamination. In this research, the resistance of six important pistachio cultivars to A. flavus and aflatoxin was first determined. The relationship between the thickness of the testa (the thin skin on the kernels) and the growth of A. flavus and aflatoxin production was then investigated. The testa of pistachio cultivars was inoculated using a toxin-producing isolate of A. flavus. Eight days after inoculation, the growth and colonization rate of the fungus was measured and evaluated using the Kernel Screening Assay (KSA) method and the amount of aflatoxin determined by the High-Performance Liquid Chromatography (HPLC) method. The thickness of testa was measured using a micrometer. To investigate the possible relationship between the thickness of testa and the growth of A. flavus and aflatoxin production, the correlation coefficient (r) was calculated. According to the results of statistical analysis, the cultivars Shahpasand and Ghaniabadi exhibited the lowest resistance to the growth of A. flavus. The research results indicated that there was no significant relationship between the amount of fungus growth and aflatoxin and the thickness of the pistachio kernel skin in different cultivars.It appears that the chemical characteristics of the pistachio kernel and kernel skin play a more important role in resistance to fungal growth and aflatoxin production. تفاصيل المقالة