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51.
Zahra Kiani Doostmorad Zafari Saeed Rezaee Amir Arjmandian Mazdasht Gitti P.C. Struik 《Archives Of Phytopathology And Plant Protection》2013,46(19):2401-2408
Globodera rostochiensis and Rhizoctonia solani are the most important growth limiting factors influencing potato production in Iran. The effects of inoculation with Potato Cyst Nematodes (PCN) (0, 50, 75 and 100 cysts/3.5?kg soil) and R. solani (with or without inoculation) on potato growth and development were investigated in cultivars Santé and Marfona. Inoculation with R. solani induced severe damage, especially when inoculation was accompanied with high density of PCN. The damage caused by R. solani tended to increase with an increase in PCN density, especially in Marfona. In Santé, number of stems or branches per plant significantly increased by inoculation with R. solani, while in Marfona it was significantly affected either by R. solani inoculation or PCN density. In Santé, number of stolons per plant was significantly increased by PCN, but not by R. solani. In Marfona, however, the number of stolons per plant was significantly affected either by R. solani inoculation or by presence of PCN, but not affected by PCN density. The general effect of R. solani or PCN inoculation treatments on shoot, below-ground and total dry weight of potato was significant, but strongly affected by cultivar. In general, our study supports the synergistic interaction between R. solani and PCN and its moderation by the use of a resistant cultivar such as Santé. 相似文献
52.
Alireza Askarianzadeh Fatemeh Jahan Gholamhosein Hasanshahi Amir Mohammad Naji Mohammad Salehitabar 《Archives Of Phytopathology And Plant Protection》2013,46(14):1740-1746
The diamondback moth (DBM), Plutella xylostella (L.) (Lep., Plutellidae), is one of the most important pests of oilseed rape, Brassica napus L., in the world. In this study, resistance of oilseed rape cultivars to DBM was evaluated in fields of Tehran based on injury rate of the cultivars. To evaluate cultivar resistance, 19 cultivars of oilseed rape were planted in randomised complete-block design with three replications. Total experiments were conducted in experimental field of Shahed University. Results showed that DBM had activity on the plants during season and peak of the injury occurred on 27 May. Results indicated that the total of oilseed rape cultivar was spotty. Statistical analysis showed that there was significant difference among determined characteristics in all cultivars. The highest and lowest numbers of holes in the leaf were observed in Midas, Karaj3, Zarfam and Hyola420, Hyola308 cultivars, respectively, in sampling of the end growth. Opera and Midas cultivars have the highest percentage of leaf infestation and the lowest percentage of leaf infestation was observed in Hyola420 and Hyola308. Also, Karaj3 and Zarfam cultivars have the highest percentage of meristem infestation and the lowest percentage of meristem infestation was observed in Licard and Hyola420 cultivars. Based on peak of the injury rate and importance of meristem injury, Hyola420 and Hyola308 cultivars were relatively resistant to DBM, and Karaj3 and Zarfam were relatively sensitive to DBM. 相似文献
53.
The aerobiology of fungi in the genus Fusarium is poorly understood. Recent work has highlighted the role of Lagrangian coherent structures (LCSs) in the movement of fusaria in the lower atmosphere. Here, we extend this work by examining the relationship between the length of atmospheric sampling intervals with autonomous unmanned aerial vehicles (UAVs) and the recovery of fusaria. UAVs were equipped with an array of eight microbe-sampling devices with four “inner” sampling arms and four “outer” sampling arms. Each set of arms was used to collect consecutive aerobiological samples during 10 min sampling periods at 100 m above ground level at the Kentland Farm in Blacksburg, Virginia. Fifty-one flights (102 consecutive sampling intervals) were conducted in 2010 and 2011. A correlation analysis showed that the counts of fusaria did not vary between the inner and outer sampling arms from consecutive sampling period of 10 min (r = 0.93, P < 0.001), and the frequency of colony counts had similar distributions for samples from the inner and outer sampling arms. An analysis of the temporal variation in the collections of Fusarium showed that the similarity between collections decreased over time. This work supports the idea that atmospheric populations of fusaria are well mixed, and large changes in the recovery of fusaria in the lower atmosphere may be attributed to large-scale phenomena (e.g., LCSs) operating across varying temporal and spatial scales. This work may contribute to effective control measures for diseases causes by fusaria in the future. 相似文献
54.
Hossein Jafari Mansoorian Amir Hossein Mahvi Ahmad Jonidi Jafari Mohammad Mehdi Amin Ahmad Rajabizadeh Narges Khanjani 《Enzyme and microbial technology》2013,52(6-7):352-357
Electricity generation from microbial fuel cells which treat food processing wastewater was investigated in this study. Anaerobic anode and aerobic cathode chambers were separated by a proton exchange membrane in a two-compartment MFC reactor. Buffer solutions and food industry wastewater were used as electrolytes in the anode and cathode chambers, respectively. The produced voltage and current intensity were measured using a digital multimeter. Effluents from the anode compartment were tested for COD, BOD5, NH3, P, TSS, VSS, SO4 and alkalinity. The maximum current density and power production were measured 527 mA/m2 and 230 mW/m2 in the anode area, respectively, at operation organic loading (OLR) of 0.364 g COD/l.d. At OLR of 0.182 g COD/l.d, maximum voltage and columbic efficiency production were recorded 0.475 V and 21%, respectively. Maximum removal efficiency of COD, BOD5, NH3, P, TSS, VSS, SO4 and alkalinity were 86, 79, 73, 18, 68, 62, 30 and 58%, respectively. The results indicated that catalysts and mediator-less microbial fuel cells (CAML-MFC) can be considered as a better choice for simple and complete energy conversion from the wastewater of such industries and also this could be considered as a new method to offset wastewater treatment plant operating costs. 相似文献
55.
Ultrasonic technology was applied for polysaccharide extraction from the leaves of Dodonaea viscosa and response surface methodology (RSM) was used to optimize the effects of processing parameters on polysaccharide extraction yield. Three independent variables were extraction time (X1), extraction temperature (X2) and ultrasonic power (X3), respectively. The statistical analysis indicated the independent variables (X1, X2, X3), the quadratic terms (X11 and X33) and the interaction terms (X1X2, X1X3, X2X3) had significant effects on the yield of polysaccharides (P < 0.05). The optimal extraction conditions of D. viscosa leaf were determined as follows: extraction time 50.54 min, extraction temperature 85 °C and ultrasonic power 400 W. Under these conditions, the experimental yield of polysaccharides was 9.455 ± 0.24%, which was agreed closely with the predicted value (9.398%). The evaluation of anti-oxidant activity suggested that the polysaccharide exhibited significant protection against DPPH and hydroxyl radicals and could be explored as a nutraceutical agent. 相似文献
56.
Masoud Mirmohammad sadeghi Amir Reza Modarresnia Farhad Shafiei 《Geomicrobiology journal》2013,30(5):453-465
The effects of experimental parameters including soil type, curing duration, inoculum size, and biomass and nutrients concentration on soil strengthening due to calcite precipitation by Sporosarcina pasteurii PTCC 1645 were investigated. The laboratory-scale mixing experiments on remolded samples were designed by the Taguchi method. Soil type proved to be the most incorporating factor, followed by curing time and nutrient concentration. The main effect and the interactions of the parameters were presented and the optimal conditions were obtained. This suggests the importance of local conditions including soil type on any future large-scale, in situ application. 相似文献
57.
Toshiaki Nakano Mayumi Miyamoto-Matsubara Mahmoud I. Shoulkamy Amir M. H. Salem Seung Pil Pack Yukio Ishimi Hiroshi Ide 《The Journal of biological chemistry》2013,288(7):4649-4658
DNA-protein cross-links (DPCs) are formed when cells are exposed to various DNA-damaging agents. Because DPCs are extremely large, steric hindrance conferred by DPCs is likely to affect many aspects of DNA transactions. In DNA replication, DPCs are first encountered by the replicative helicase that moves at the head of the replisome. However, little is known about how replicative helicases respond to covalently immobilized protein roadblocks. In the present study we elucidated the effect of DPCs on the DNA unwinding reaction of hexameric replicative helicases in vitro using defined DPC substrates. DPCs on the translocating strand but not on the nontranslocating strand impeded the progression of the helicases including the phage T7 gene 4 protein, simian virus 40 large T antigen, Escherichia coli DnaB protein, and human minichromosome maintenance Mcm467 subcomplex. The impediment varied with the size of the cross-linked proteins, with a threshold size for clearance of 5.0–14.1 kDa. These results indicate that the central channel of the dynamically translocating hexameric ring helicases can accommodate only small proteins and that all of the helicases tested use the steric exclusion mechanism to unwind duplex DNA. These results further suggest that DPCs on the translocating and nontranslocating strands constitute helicase and polymerase blocks, respectively. The helicases stalled by DPC had limited stability and dissociated from DNA with a half-life of 15–36 min. The implications of the results are discussed in relation to the distinct stabilities of replisomes that encounter tight but reversible DNA-protein complexes and irreversible DPC roadblocks. 相似文献
58.
Amir Reza Hajrasouliha Guomin Jiang Qingxian Lu Huayi Lu Henry J. Kaplan Huang-Ge Zhang Hui Shao 《The Journal of biological chemistry》2013,288(39):28058-28067
Exosomes released from different types of host cells have different biological effects. We report that exosomes released from retinal astroglial cells (RACs) suppress retinal vessel leakage and inhibit choroidal neovascularization (CNV) in a laser-induced CNV model, whereas exosomes released from retinal pigmental epithelium do not. RAC exosomes inhibit the migration of macrophages and the tubule forming of mouse retinal microvascular endothelial cells. Further, we analyzed antiangiogenic components in RAC exosomes using an angiogenesis array kit and detected several endogenous inhibitors of angiogenesis exclusively present in RAC exosomes, such as endostatin. Moreover, blockade of matrix metalloproteinases in the cleavage of collagen XVIII to form endostatin using FN-439 reverses RAC exosome-mediated retinal vessel leakage. This study demonstrates that exosomes released from retinal tissue cells have different angiogenic effects, with exosomes from RACs containing antiangiogenic components that might protect the eye from angiogenesis and maintain its functional integrity. In addition, by identifying additional components and their functions of RAC exosomes, we might improve the antiangiogenic therapy for CNV in age-related macular degeneration and diabetic retinopathy. 相似文献
59.
Amir Sherman Ravit Eshed Rotem Harel-Beja Galil Tzuri Vitaly Portnoy Shahar Cohen Mor Rubinstein Arthur A. Schaffer Joseph Burger Nurit Katzir Ron Ophir 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(2):349-358
The availability of sequence information for many plants has opened the way to advanced genetic analysis in many non-model plants. Nevertheless, exploration of genetic variation on a large scale and its use as a tool for the identification of traits of interest are still rare. In this study, we combined a bulk segregation approach with our own-designed microarrays to map the pH locus that influences fruit pH in melon. Using these technologies, we identified a set of markers that are genetically linked to the pH trait. Further analysis using a set of melon cultivars demonstrated that some of these markers are tightly linked to the pH trait throughout our germplasm collection. These results validate the utility of combining microarray technology with a bulk segregation approach in mapping traits of interest in non-model plants. 相似文献
60.
Yoav Gazit Sagi Gavriel Ruti Akiva Doron Timar 《Entomologia Experimentalis et Applicata》2013,147(2):120-125
GF‐120, a fruit fly bait designed to attract and kill adult fruit flies, was tested in the laboratory and outdoors to determine effects of pre‐treatment diet and bait aging on mortality of Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). Two spinosad‐based compounds, GF‐120 and Tracer® Ultra, had generated two distinctive dose–mortality responds, with LC80, LC90, and LC99 values of 2.4, 2.8, and 4.1 p.p.m., and 255, 479, and 1 143 p.p.m., respectively. The residues of GF‐120 drops, after feeding to the flies, generated 14.3% mortality. The droplet size of the baited spray plays an important role. The toxicity of large drops lasted more than that of small droplets. In the field, exposure to the sun further deteriorates the compound, which lost 50% of its toxicity within 6 days. Disappearance of the compound in the field, due to consumption by various insects, also played a role as 50% of the GF‐120 drops disappeared within 7 days. As mortality was directly related to the amount of insecticide eaten, the effect of GF‐120 depended on the feeding status of the flies: well‐fed flies were almost unaffected compared with starved ones. 相似文献