فهرست مطالب

Crop Protection - Volume:2 Issue:4, 2013
  • Volume:2 Issue:4, 2013
  • تاریخ انتشار: 1392/07/08
  • تعداد عناوین: 12
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  • Amir Amiri Sadeghan, Masoud Shams, Bakhsh, Bagher Yakhchali Pages 387-393
    Citrus tristeza virus (CTV) is among the most destructive pathogens of citrus and causes substantial economic losses in citrus-growing industry worldwide. Considering recent distribution of this pathogen and its capability of transmission by existing aphid vectors in Iran, detection of this virus is enforceable for controlling the damage caused by this pathogen in Iran, as one of the major citrus producing countries. Toward this aim, developing a reliable and sensitive detection method such as enzyme- linked immunosorbant assay (ELISA) would be the first step to detect CTV in large scale screenings of field samples. As the serological method requires great amounts of specific antibody, the consequent preparation of a large scale antigen source for immunization process is necessary. In this study the coat protein gene of CTV (CP25) was amplified by polymerase chain reaction from a cloned CP25 gene in pTZ57R/T and subcloned in pET26b expression vector and named pET-CP25. Two Escherichia coli strains of BL21 and Rosetta Gami (DE3) were transformed by pET-CP25. Expression of recombinant protein was induced by IPTG. The authenticity of recombinant protein was confirmed by western immunoblot analysis using a polyclonal antiserum against CTV particles. The results indicated that CTV coat protein gene was expressed in E.coli. This recombinant protein could be used as a source of antigen for immunization process.
    Keywords: recombinant protein, western blot analysis, ELISA
  • Mortaza Rasekh Adel, Hussein Sadeghi Namaghi, Mojtaba Hosseini Pages 395-402
    To evaluate the effects of presence of insect pollinators on quantity and quality of seeds of two common cultivars of onion (Allium cepa L.), namely Red Azar Shahr and Yellow Sweet Spanish, an experiment in a factorial randomized complete block design was carried out at two sites. Bulbs of equal size were planted with plant to plant 35 cm and row to row 50 cm spacing. At each site, experimental groups differ only in pollination method. About a week before flowering start, at each site 3 groups of 10 individual inflorescences as block replications of each treatment combination (pollination × cultivar) were selected randomly and marked. For each onion cultivar, half of the plants were left uncovered (free pollination), whereas the other ones were isolated from insect pollinators by using wooden cages covered with cloth net. When about 10 percent of black seeds were visibly exposed in the umbels, harvest was done. After drying, the number and weight of seeds produced per inflorescence as well as 1000 seed weight was measured for each treatment combination. Four weeks after the harvesting date the germination test of seeds produced in each treatment combination was evaluated. Non availability of insect pollinators during the flowering period of onion caused substantial reduction on seed number and seed weight per umbel. Also, free pollination flowers showed higher germination capacity than those isolated from insect visitors. However, varieties as well as experimental sites did not show significant influences on seed setting of onion.
    Keywords: Onion, pollination, seed, Iran
  • Hooshang Rafiee, Dastjerdi, Zeinab Mashhadi, Aziz Sheikhi Garjan Pages 403-409
    The potato tuber moth (PTM), Phthorimaea operculella (Zeller) is one of the important pests of potato in tropical regions. In this research, the toxicity of two insecticides, abamectin and deltamethrin on P. operculella were studied at 26 ± 1 C°, 65 ± 5% RH and photoperiod of 16:8 h (L: D). The concentrations were determined by preliminary dose setting experiments. Distilled water was used as control. LC50 values for egg, first instar larvae and adult stages in abamectin were 0.92, 0.014 and 0.46 mg AI/L and in deltamethrin were 0.09, 0.024 and 0.29 mg AI/L, respectively. The sublethal effects of abamectin and deltamethrin on population growth parameters of P. operculella were determined at mentioned conditions. Four hundred 1 day old eggs of the pest were dipped in insecticides solutions (LC30). After egg hatching, the first instar larvae were transferred on potato tubers and placed in transparent plastic dishes. After adults'' emergence, 20 females were used for each treatment in life table experiments. In control, abamectin and deltamethrin treatments intrinsic rates of increase were estimated to be 0.060, 0.042 and 0.141 day-1, respectively. Statistical analyses showed that deltamethrin had the higher toxicity to egg and adult stages of PTM and abamectin had the higher toxicity to its first instar larvae. But deltamethrin increased the stable population parameters of P. operculella specially its intrinsic rate of increase, thus it is not recommended to control PTM. Based on lethal and sublethal effects, abamectin could be a suitable compound to control PTM.
    Keywords: Phthorimaea operculella, lethal, sublethal, insecticides, demography
  • Hajar Faal, Mohammad, Ali, Parviz Shishehbor Pages 411-419
    The effect of host diet on developmental time, fecundity and life-table parameters of Bracon hebetor (Say) (Hymenoptera: Braconidae) against the Mediterranean flour moth Ephestia kuehniella (Zeller) was studied in the laboratory conditions at 26 ± 1 °C, 65 ± 5% relative humidity and a photoperiod of 16L:8D h. The diets used were rice, barley, corn and wheat flours. The developmental time (egg to adult) of the first and second generations ranged from 9.00 to 14.00 days on barley flour and wheat flour, respectively. The survival of immature generations 1 and 2 ranged from 27 to 63%. The sex ratio of wasp progeny (females/total) ranged from 36.72 to 57.83% on wheat flour and rice flour, respectively. In the first and second generations, the fecundity of B. hebetor reared on barley and rice flours was greatest. Life table parameters varied significantly with host diets. In generation 2, B. hebetor-parasitized larvae reared on rice flour showed the highest net reproduction rate (R0 = 106.13) and the highest intrinsic rate of increase (rm = 0.269) of parasitoids. Based on the life-table analyses, rice flour was found the best diet for rearing the parasitoid. The results of this study can be used to improve mass-rearing programs of B. hebetor.
    Keywords: Bracon hebetor, host diet, developmental time, fecundity, life table parameters
  • Mahdieh Hosseini Moghaddam, Jalal Soltani, Freydoun Babolhavaeji, Javad Hamzei, Sonbol Nazeri, Soheila Mirzaei Pages 421-433
    The cypress family, Cupressaceae, has a global dispersion. Currently, endophytic microorganisms from plants are being investigated for their diversity and bioactivities. Here, we aimed at exploration and characterization of cultivable endophytic fungi from foliar tissues of Cupressaceae, i.e. Cupressus arizonica, C. sempervirens var. cereiformis, C. sempervirens var. fastigiata, Juniperus excelsa, Juniperus sp. and Thuja orientalis. Asymptomatic fresh foliar tissues, collected from mature healthy plants, were sterilized and the inner layers were plated on culture media at 26-28 °C for 2-12 weeks, until fungal colonies emerged and were purified. Endophytic penicillia i.e. Penicillium aurantiogriseum, P. chrysogenum, P. commune, P. echinulatum, P. expansum and P. viridicatum were the dominant fungi recovered. Results indicated that both host plant and geographical location of sampling affected the biodiversity and bioactivity of endophytic Penicillia. Results also indicated that these endophytic Penicillia had significant bioactivities. According to our results, both intra-and extra-cellular secondary metabolites from all isolated Penicilliahad significant cytotoxic and antifungal effects against the model fungus Pyricularia oryzae and cypress fungal phytopathogens Diplodia seriata, Phaeobotryon cupressi and Spencermartinsia viticola. Further studies indicated the significant antimicrobial bioactivities of superior Penicillia against model bacteria. Altogether, this study highlights, for the first time, the biodiversity of endophytic Penicillia from Cupressaceae plants and documents their significance for agrochemical/drug discovery and for plant disease biocontrol.
    Keywords: Penicillium, endophyte, Cupressaceae, antiproliferative, antifungal, antimicrobial, biocontrol
  • Farhkhondeh Ommati, Masoud Zaker, Alireza Mohammadi Pages 435-442
    Application of Trichoderma species is a harmless method in controlling soil borne plant diseases thus reducing hazardous pesticide use and environmental pollution. Some Trichoderma isolates performing proper inhibitory effect against Fusarium oxysporum f. sp. tuberosi under laboratory and green house conditions were screened against wilt disease of potato caused by this pathogen under field condition in Shahrood Agricultural Research Center, Iran, during 2009-2010. Results of two years field studies indicated that T. virens (T7) followed by T. asperellum (T2) were superior to others in reducing the disease in comparison to infested control. In comparison to Fusarium infested plots, yield was higher in all plots treated with Trichoderma, but highest yields were obtained from plots in which T. virens (T7) and T. asperellum (T2) were involved respectively. It might be stated that isolates of T. virens and T. asperellum are among the effective biocontrol agents against Fusarium wilt disease of potato and can be used as formulated biofungicides in reducing this disease.
    Keywords: biocontrol, Trichoderma, Fusarium wilt, Potato, Yield
  • Ensieh Keivanloo, Hussein Sadeghi Namaghi, Mohammad Hossein Haddad Khodaparast, Saeed Hatefi Pages 443-451
    Ozone is a powerful oxidant capable of killing insects and microorganisms has been used in the food processing industry in the gaseous and aqueous states. In a laboratory study, the susceptibility of immature stages of an important stored-product pest, the Indian meal moth, Plodia interpunctella Hubner to ozonated water was investigated. Ozone was applied as aqueous form at four concentrations (0, 2, 3 and 5 ppm) for four different periods (30, 60, 90 and 120 min) on eggs, larvae and pupae of, P. interpunctella. The results indicated that in all tested stages, the rate of mortality increased concomitant with increasing of concentration and exposure time. This study showed that 5-day old larvae were more susceptible than other stages (12-, 17-day old larvae, pupae and eggs) when exposed to 5 ppm ozone for 120 min. Following 5-day old larvae, 12-day old larvae, 17-day old larvae and pupae had the highest sensitivity to ozonation. At the highest concentration of ozone for the longest time, the least mortality rate was recorded for one day old eggs. According to these preliminary results, ozonated water has potential of reducing population density of P. interpunctella, one of the most important pests of dried fruits such as date, almond and pistachio in storage.
    Keywords: Post harvest pests, Ozonated water, Plodia interpunctella
  • Maryam Darbemamieh, Hamidreza Hajiqanbar, Mohammad Khanjani Pages 453-460
    The present checklist is compiled of the eupodoid mites of Iran using published records and original data from recent researches. It contains 19 species belonging to 13 genera and five families. Family Cocceupodidae Jesionowska, 2010 (because of moving the genera to a new family) and two species i.e. Foveacheles (Foveacheles) cegetensis Zacharda, 1983 and Linopodes antennaepes Banks, 1894 are new records for Iranian mite fauna. In addition to some corrections to specific identities which have been previously reported in Iranian literatures, we report here known geographical distribution and habitats in Iran and distribution in the world as well.
    Keywords: Eupodoid mites, checklist, new record, Foveacheles (Foveacheles) cegetensis, Linopodes antennaepes, Iran
  • Elham Yazdani, Jalal Jalali Sendi, Alireza Aliakbar Pages 461-476
    Mulberry pyralid, Glyphodes pyloalis Walker is an important pest on mulberry. The essential oil of Rosemary Rosemarinus officinalis L. (Lamiales: Lamiaceae) has been investigated on toxicity and physiological characteristics of this moth under controlled conditions. The major compounds of the oil were analyzed as 1, 8 Cineol (20.021%), Borneoll (7.17%), L. Camphor (6.541%), Geraniol (6.281%), Camphen (5.623%), Linalool (4.993%) Alpha fenchyl acetate (4.222%) and Verbenone (4.147%). Lethal and sublethal concentrations (LC10, LC30 and LC50) were estimated 0.77%, 1.18% and 1.59% (v/v) respectively. The essential oil affected the nutritional indices of fourth instar larvae of G. pyloalis. Efficiency of Conversion of Ingested food (ECI), Efficiency of Conversion of Digested food (ECD), Relative Consumption Rate (RCR) and Relative Growth Rate (RGR) have been reduced in larvae treated with R. officinalis essential oil while Approximate Digestibility (AD) in treated larvae showed difference compared with the control. The essential oil affected the insect some key metabolic compounds like; lipid, protein and carbohydrates. Similarly this effect was also significant in the activities of certain key enzymes like; alpha- amylase, lipase, protease, glutathione-s-transferase and esterases.
    Keywords: Glyphodes pyloalis, Rosmarinus officinalis, GC, MS, nutritional indices
  • Ehsan Parsaeyan, Moosa Saber, Mohammad Bagheri Pages 477-485
    Cotton bollworm, Helicoverpa armigera (Hübner) is one of the most destructive insect pests on many crops in the world that has been found to develop resistance against conventional insecticides. Using insecticides with different mode of actions may results on appropriate control of the pest and delay insecticide resistance development. In this study, lethal and sublethal effects of emamectin benzoate and cypermethrin insecticides were investigated on third instar larvae of H. armigera by residue contact methods at 26 ± 1 oC, 70 ± 5% RH and a photoperiod of 16:8h (L: D) under laboratory conditions. LC50 values on larval stage of the pest of emamectin benzoate and cypermethrin were 1.75 and 127.74 µg a.i./ml, respectively. According to the findings, the larvae that were exposed to the LC30 of emamectin benzoate and cypermethrin exhibited lower pupal weight and increased larval and pupal developmental times compared with control. The longevity and fecundity of adults were significantly affected by the insecticides. Emamectin benzoate and cypermethrin reduced fecundity by 53.1% and 50.5%, respectively compared to control. The LC30 values of emamectin benzoate and cypermethrin reduced egg hatching by 62.06% and 37.9%, respectively. We predicted that the insecticides, especially emamectin benzoate, may induce significant effects on population of H. armigera.
    Keywords: cotton bollworm, lethal, sublethal effects, longevity, fecundity
  • Chemotyping of Fusarium graminearum using Tri13 trichothecene biosynthetic gene
    Mostafa Abedi, Tizaki, Seyed Kazem Sabbagh, Mahta Mazaheri Naeini, Saedeh Sepehrikia Pages 487-500
    Fusarium graminearum is one of the most important causes of FHB or wheat scab in different part of the world. This fungus is able to produce widespread Trichothecene mycotoxins such as Nivalenol (NIV) and Deoxynivalenol (DON) which are harmful for both human and animals. To determine chemotypes of Trichothecene, a total of 100 isolates from different fields of Golestan province in Iran including Gorgan, Kordkuy, Bandaregaz, Gonbad, Minodasht, Kalaleh and Azadshahr were identified as F. graminearum using morphological features then 96 isolates were confirmed by polymerase chain reaction (PCR) assay using F. graminearum species-specific primers (Fg16F/Fg16R). Based on sequences of Tri13 gene involved in the mycotoxin biosynthetic pathway, PCR assays was used to detect Nivalenol (NIV) and Deoxynivalenol (DON) chemotypes. Of the 96 tested isolates with Tri13 PCR assays, 70 classified as NIV chemotype and the remaining 26 isolates as DON producers. These results indicated that NIV chemotype was the most dominant chemotype in studied zones. A greater proportion of NIV chemotype was found in Gorgan fields (P < 0.05, P < 0.0001), whereas greater proportion of DON was detected in Gorgan and Gonbad fields (P < 0.05, P < 0.0001). Chemotyping by PCR assay were confirmed using HPLC method. These results demonstrated that PCR assay and HPLC could be used as rapid, reliable and cost-effective methods for the detection and identification of mycotoxin-producing Fusarium-species and may thus help to develop strategies to avoid or reduce mycotoxin contamination of cereals.
    Keywords: Fusarium graminearum, trichothecene, chemotypes, NIV, DON
  • Modeling fluctuation of Pyricularia grisea spore population as affected by meteorological factors in Guilan province (Iran) using artificial neural network
    Shideh Mojerlou, Sedigheh Mousanejad, Naser Safaie Pages 501-514
    Rice blast, caused by Pyricularia grisea, is one of the most important diseases of this crop in Iran and all over the world. To evaluate the relationship between spore population (SP) and meteorological factors, SP was measured daily using spore trap during growing seasons of 2006-2008 in Rasht and Lahijan regions (Guilan province, Iran). Weather data including precipitation, daily maximum and minimum temperatures, daily maximum and minimum relative humidity and duration of sunny hours were obtained from weather stations which were five kilometers away from the fields. The relationship between spore population and metrological factors was evaluated by Neurosolution 5.0 software. Weather data and spore population were considered as input and output data, respectively. In this study, multilayer perceptron neural network, regression model and Log(x + 1) transformation were performed. To evaluate the model efficiency, correlation coefficient and mean square error were used. The results showed that the correlation coefficient (r) and mean square error (MSE) parameters were 0.55 and 0.03 in Rasht and 0.1 and 0.03 in Lahijan, respectively. The results also showed the potential of this model for modeling SP using meteorological factors; however more data is needed for validation of this model. There has been no previous report on modeling the relationship between SP and meteorological data using artificial neural network in Guilan province (Iran).
    Keywords: artificial neural network, blast, forecasting, Pyricularia grisea, rice