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Lycoriella auripila (Winnertz) (Diptera: Sciaridae) is one of the most frequently seen pests of cultivated mushrooms, Agaricus bisporus (Lange) Imbach. The effects of different concentrations of diazinon, imidacloprid and deltamethrin, and tobacco extract were tested against L. auripila on varieties 737 and A15 of button mushroom. Also, economic injury level (EIL) of fungus gnat was evaluated on variety 737. Different varieties of button mushroom were cultured and weight of harvested mushrooms was recorded to provide an estimate of yield loss. A linear regression analysis was used to determine the relationship between pest density and mushroom yield. Imidacloprid was the most effective insecticide against L. auripila on both varieties and caused 100 % control at the highest tested concentration. The lowest concentration of diazinon (500 ppm a.i.) increased pest emergence on 737 and A15. This is possibly due to the hormoligosis. Deltamethrin and tobacco extract were ineffective against fungus gnat between both varieties. High levels of adults of L. auripila were associated with significant reduction in mushroom yield. EIL were calculated according to the number of L. auripila required to cause the critical yield loss from the predictive model and by control costs, mushroom price, and the reduction of injury due to spraying by imidacloprid and diazinon. The lowest values of EIL were related to imidacloprid compared with diazinon. This is due to the different efficiency of these two insecticides, for it causes mortality in population of L. auripila. Based on this research, for the first time clear EILs are introduced to the button mushroom growers for treatment of L. auripila.  相似文献   
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Plant Foods for Human Nutrition - Saffron is the most expensive spice in the world; so, determining optimum conditions for its processing is crucial. The most important processing stage of saffron...  相似文献   
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One of the most common strategies in the treatment of cognitive disorders is enhancing the acetylcholine level in the brain through the inhibition of acetylcholinesterase. Despite the effectiveness of current modern drugs, more attention has been paid for finding new anticholinesterase agents from medicinal plants. Zatraia multiflora Boiss. is an endemic plant to Iran which has different uses in traditional medicine as anti-inflammatory, antimicrobial, anti spasmodic. We intended to evaluate the in vitro anticholinesterase and free radical scavenging activity of the essential oil and methanolic extract of Z. multiflora. The essential oil and methanolic extract of the plant were evaluated for anticholinesterase activity using modified Ellman method. The free radical scavenging effect of the samples were studied by using of the diphenylpicrylhydrazyl (DPPH). IC50 and the percent of inhibition of acetylcholinesterase was calculated from regression equation. The results showed that both the essential oil and methanolic extract of the plant exhibited high anticholinesterase activity (95.3 +/- 3.4 and 87.9 +/- 2.2% inhibition, respectively) which was similar to eserine (96.2 +/- 1.7% inhibition). The IC50 value of essential oil was determined as 0.97 +/- 0.12 microg mL(-1) in comparison to eserine (0.13 +/- 0.02 microg mL(-1)). The results of antioxidant assay showed that both the essential oil and methanolic extract potentially inhibit DPPH free radical (94.8 +/- 2.4 and 93.2 +/- 1.7% inhibition, respectively). The essential oil and methanolic extract of Z. multiflora have beneficial effect in health promotion and this plant would be good candidate for further studies.  相似文献   
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Physiological parameters and growth performance of Huso huso fingerlings fed with diet supplemented with herbal plants were studied in this study. Dietary treatments were 0 g (= control), 1.0 g (garlic) and 1.0 g (ginger) of 100 g?1 feed for 60 days. Specific growth rate, body weight gain and condition factor were significantly increased in ginger treatment at the end of the trial. Highest levels of erythrocyte and hematocrit were observed in fingerlings ginger group after 60 days. Globulin increased significantly in ginger group, and the highest level of albumin was observed in garlic group. To sum up, it seems that herbal diet can improve some growth and physiological parameters in this species.  相似文献   
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This study provides an alternative solution for the bioremediation of a recalcitrant pharmaceutical micropollutant. Clofibric acid (CLA) was chosen as target molecule, because of its environmental persistence and resistance to wastewater treatment technologies. The aim of this study was to investigate the potential of a phenol-resistant Pseudomonas aeruginosa strain isolated from the activated sludge to degrade CLA. In order to evaluate the effect of acclimation process with glucose as carbon co-substrate, two protocols were performed, in which the transfer of the inoculum is carried out either in the exponential growth phase or in the decline phase. The results showed a removal efficiency of CLA of 35% when cells in the decline phase were used for inoculation. In contrast, a very low removal yield (10%) was achieved when cells harvested in the exponential phase were used as inoculum. This work is the first one reporting on the capability of this bacterium to remove this drug. The obtained data showed that the isolated strain is able to degrade target molecule and might be a promising agent for the elimination of this refractory compound.  相似文献   
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