فصلنامه تحقیقات آفات گیاهی
سال یازدهم شماره 1 (بهار 1400)

During 2018-2019, fauna of prostigmatid (Acari: Prostimata) mites associated with greenhouse plants were investigated in Rasht city, Guilan province, Northern Iran. In this study totally, 25 species from 20 genera and 12 families were collected and identified. The list of identified species base on family is as follows. New records for Iran and Guilan province are marked by two and one asterisks, respectively.Anystidae: Anystis baccarum (Linnaeus, 1758); Bdellidae: Cyta latirostris (Hermann, 1804)*, Spinibdella cronini (Baker and Balock, 1944); :; Camerobiidae: Tycherobius sp.**; Cheyletidae: Cheletomorpha lepidopterorum (Show, 1794), Cheyletus eruditus (Schrank, 1781), C. ferox Banks, 1906**, C. rapax Oudemans, 1903**; Cunaxidae: Armascirus cerris Kaluz, 2009**, Coleoscirus simplex (Ewing, 1917), Coleoscirus tuberculatus Den Heyer, 1978*; Erythraeidae: Abrolophus iraninejadi Saboori and Hajiqanbar, 2005, Erythraeus (Zaracarus) ueckermanni Saboori, Nowzari & Bagheri-Zenouz, 2004; Raphignathidae: Raphignathus hecmatanaensis Khanjani and Ueckermann, 2003; Tarsonemidae: Polyphagotarsonemus latus (Banks,1904); Tenuipalpidae: Brevipalpus obovatus Donnadieu, 1875, Pentamerismus ueckermanni Khanjani and Gotoh, 2008*; Tetranychidae: Panonychus citri (McGregor, 1916), Petrobia (Petrobia) latens (Müller, 1776), Petrobia (Tetranychina) harti (Ewing, 1909)*; Tetranychus urticae Koch, 1836; Triophtydeidae:Triophtydeus immanis Kuznetzov, 1973*, 1973; Tydeidae: Brachytydeus mali (Oudemans, 1929), Tydeus kochi Oudemans, 1928*, T. meshkinensis  André, Ueckermann and. Rahmani, 2010.

Frequent and extensive use of various pesticides to control of common pistachio psylla (Agonoscenapistaciae), as one of the most important pests of pistachio, has provided the possibility of reduced susceptibility of this pest to pesticides. In this study, the susceptibility of 13 populations of A. pistaciae collected from pistachio orchards at areas of Bardaskan, Khalil Abad and Feiz Abad were studied to imidaclopridand to chlorpyrifos using bioassay experiments by leaf disc dipping method and based on the discriminating dose. The bioassay results indicated that the LC50 values of imidacloprid and chlorpyrifos on the susceptible population were determined as 261.2 and 83.03 ppm, respectively. The bioassay with discriminating dose (i.e. LC90 of the susceptible population) showed that all of the tested populations were susceptible to chlorpyrifos. But there were significant differences in susceptibility to imidacloprid between different populations compared to the susceptible one. The highest mortality percentage applying the discriminating dose was obtained for Kondor- susceptible population and the lowest one was related to Jalal-Abad, Zaher Abad and Kondor- resistant populations. The biochemical assays with measuring the esterase activity demonstrated that one of the mechanisms reduce susceptibility was an increase of esterase activity; so that, the activity of the susceptible population was 2.5 times less than that of populations that had low sensitivity. Furthermore, zymogram analysis showed that all populations had 2 enzyme bonds that qualitatively differ in the case of non-sensitive populations compared to the susceptible one. Measurement of glutathione S-transferase activity also showed that this enzyme system was involved in the reduction of the susceptibility of common pistachio psylla to imidacloprid.

Vegetable leafminer, Liriomyza sativae Blanchard, is one of the most important pests of cucumber, especially in greenhouses. In this study, effect of different fertilizer treatments, including vermicompost, humic acid, nitrogen, vermicompost-humic acid and vermicompost-humic acid-nitrogen mixture, were investigated on biological parameters of vegetable leafminer along with some growth indices of cucumber plant including plant height and chlorophyll content. The experiments were carried out in a growth chamber at 25 ± 2˚C, relative humidity of 65 ± 5 %, and a photoperiod of 16 L: 8 D. Based on the results, the duration of immature stages and longevity of adults were significantly different on the tested treatments. Duration of immature stages was highest on humic acid treatment (3.36 d) and lowest on control (3.13 ± 0.06). Furthermore, the lowest values of longevity and life span of adults were recorded on humic acid (6.57 and 27.21 d, respectively) and the highest values of these parameters were on nitrogen treatment (11.14 and 30.11 d, respectively). The tested treatments had significant effects on population growth parameters of the pest. The highest values of intrinsic rate of natural increase (r) and net reproductive rate (R0) of the vegetable leafminer were on nitrogen treatment (0.1640 d-1 and 52.70 offspring/female, respectively) and the lowest values of these parameters were on humic acid treatment (0.0888 d-1 and 9.67 offspring/female, respectively). The results of the present study showed that humic acid can be used in integrated management of the vegetable leafminer in cucumber growing area.

In the present study, the effect of hexytiazox, nano sulfur, alginate/sulfur (Al/S) and alginate/sulfur/hexytiazox (A/H/S) composites were examined on adult famale of two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae). The diameters of sulfur nanoparticles and sodium/sulfur alginate and sodium/sulfur/hexithiazox alginate 300-60 nm were obtained using electron microscopy (SEM). Analysis of FT-IR spectra of sulfur alginate/sulfur (Al/S) and alginate/sulfur/hexytiazox (A/H/S) composites were performed, in the sulfur spectrum, only two peaks 870 and 3435, and in the alginate spectrum 1630, 1457 and 1341 peaks were observed. The highest mortality was obtained 24, 48 and 72 hours after application in the composite (Al/He/S) treatment with LC50 values of 3.48, 2.80 and 2.43 g/l, respectively. Also the lowest mortality was observed 24 hours after using nanosulfur treatment with LC50 value of 20.34 g/l and in 48 and 72 hours in nanosulfur and alginate/sulfur (Al/S) composite treatment with LC50 values of 12.37 and 9.87 g/l, respectively. Hexithiazox treatment with a concentration of 12.7 ml/l after 72 hour aplication showed the highest mortality (70%). Based on the results of this study, composite (Al/He/S) can be recommended in the preparation of commercial acaricide formulations and use in T. urticae integrated management program.

Biological pesticides have advantages to chemicals that safety to non-target organisms is of the most important ones. Slugs are parasitized or preyed by several organisms such as nematodes. In this research, integrated management of grey slug Parmacella ibera was assessed by Phasmarhabditis hermaphrodita, Metaldehyde and Fericol in field conditions in Someh Sara, Guilan Province. The treatments included: untreated, P. hermaphrodita recommended dose, P. hermaphrodita recommended dose + Fericol, P. hermaphrodita ½ dose and P. hermaphrodita ½ dose +Metaldehyde ½ dose on P. ibera assessed based on the percent of dead slugs, mean percent of damaged leaves, the number of leaves with damage symptoms and the number of plants with damage symptoms. Results showed the highest percent of dead slugs in P. hermaphrodita ½ dose +Metaldehyde ½ dose. Mean percent of damaged leaves was not significantly different among P. hermaphrodita treatments along with Fericol and metaldehyde. Results indicated that P. hermaphrodita ½ dose + Metaldehyde ½ dose treatment had considerable effect in all parameters on pest control besides a decrease in the damage.

In the present study, the lethal and sublethal effects of essential oils of marjoram, basil, and mint were evaluated on P. operculella. Also, the parasitism percentage of T. brassicae was assessed on the eggs of P. operculella treated with sublethal concentration (LC30) of these essential oils under laboratory conditions. The gas chromatography-mass spectroscopy analysis indicated that carvacrol (26.02%), estragole (62.27%), and carvotanacetone (57.47%) were the major constituents of the studied essential oils, respectively. Based on the LC50 values of marjoram, basil, and mint essential oils (3.59, 2.53, and 2.37 µl/liter air, respectively), the mint essential oil had the highest fumigant toxicity on the eggs of P. operculella compared to other essential oils. The LC30 values of essential oils (2.61, 1.20, and 1.81 µl/liter air, respectively) were used to evaluate the sublethal effects. The sublethal concentrations of essential oils significantly affected the parameters of P. operculella. The shortest and longest total pre-oviposition period (TPOP) were observed on control (19.60 days) and O. basilicum essential oil (22.19 days). The values estimated for intrinsic rate of increase (r) in the control and marjoram, basil, and mint essential oils were 0.19, 0.11, 0.12, 0.10 day, respectively. Also, the parasitism rate of T. brassicae was recorded on control (81.11%) followed by basil essential oil (64.44%). These results suggested simultaneous usage of essential oils and parasitic wasps as a reliable option for sustainable managementofpotato tuber worm in the storage facilities.

In this study, the effect of sowing date of pinto bean (native variety of Khomein) on the control of two important pests, Empoasca decipiens Paoli (Hemiptera.: Cicadellidae) and Thrips tabaci Lindeman (Thysanoptera: Thripidae) and yield components were conducted in the experimental field, during the two crop years. The experiment was performed in a randomized complete block design with a split-plot arrangement and two factors: pesticide application (spraying and no spraying with pesticide) and sowing date (early May, late May, and mid-June) four replications. The evaluated traits included pod number per plant, seed number per pod, seed weight per plant, 100-seed weight, seed yield, and damage index. The result showed that the pesticide application factor had no significant effect on yield components in both cropping years, except 100-seed weight in the first year. Also, in the second crop year, spraying against pests significantly reduced the damage index. The results of the analysis of variance showed that sowing date had a significant effect on seed number per plant, seed weight per plant, 100-seed weight, seed yield, and damage index. The highest seed yield, the lowest damage index, and the lowest population density of T. tabaci and E. decipiens were in the third sowing date (mid-June).