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Phytoparasitica - Diaeretiella rapae (McIntosh) (Hymenoptera: Braconidae) is one of the most promising, effective and a common endoparasitoid of different aphid species including cabbage aphid,...  相似文献   
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This study was undertaken to ascertain the antipsychotic properties of Rauwolfia tetraphylla L. leaves and to isolate and characterize the antipsychotic constituents. Among the MeOH extract and some alkaloidal fractions at different pHs, the alkaloidal CHCl(3) fraction at pH-9 (2C) showed the highest antipsychotic activity against dopaminergic (DA-D(2)) and serotonergic (5-HT(2A)) receptors in-vitro and amphetamine induced hyperactive mouse model in-vivo. The activity guided isolation of CHCl(3) fraction (2C) afforded six indole alkaloids: 10-methoxytetrahydroalstonine (1), isoreserpiline (2), an isomeric mixture of 11-demethoxyreserpiline (3) and 10-demethoxyreserpiline (4), α-yohimbine (5) and reserpiline (6). Given orally, alkaloids 3-6 showed significant antipsychotic activity in a dose dependent manner. None of the extract, alkaloidal fractions or alkaloids showed any extra pyramidal symptoms at the tested doses. It was also observed that MeOH extract was behaving similar to other clinically used novel atypical antipsychotics in having 5-HT(2A) occupancy greater than the DA-D(2) receptor at the tested doses. Further toxicity and safety evaluation studies of MeOH extracts of R. tetraphylla leaves at different doses (10, 100, 300 and 2000 mg/kg) on female Swiss albino mice showed that MeOH extract is non toxic. The isolated alkaloids, 3-6 could serve as a promising lead structure for drug development of treating psychotic conditions in human.  相似文献   
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Manure application on frozen soil, which is a common practice in the upper Midwest of USA, results in degraded soil and water quality. During snowmelt or precipitation events, water runoff carries nutrients into nearby streams and impairs the water quality. There is a need, therefore, to identify improved management of manure application in the soils. This study was conducted to assess water quality impacts associated following manure application during winter months when soil is completely covered with snow. The study site included three watersheds, named south (SW), east (CW), and north (NW) managed with a corn (Zea mays L.)-soybean (Glycine max L.) rotation located in South Dakota. The SW and NW were used as treatment, and CW as the control watershed. The treatments included manure application on the upper half of the SW and lower half of the NW, and CW received no manure application. This study showed that manure improved soil properties including infiltration rate and organic matter. Nitrogen and phosphorus losses in the surface runoff were higher from NW compared to that of SW. The CW had similar nutrient losses compared to the NW with slight differences. It can be concluded that maintaining a setback distance can help in improving the environmental quality as well as managing the agricultural wastes during the winter months.  相似文献   
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It is globally accepted that soil carbon (C) dynamics are at the core of interlinked environmental problems,deteriorating soil quality and changing climate.Its management remains a complex enigma for the scientific community due to its intricate relationship with soil nitrogen (N) availability and moisture-temperature interactions.This article reviews the management aspects of soil C dynamics in light of recent advances,particularly in relation to the availability of inorganic N pools and associated microbial processes under changing climate.Globally,drastic alterations in soil C dynamics under changing land use and management practices have been primarily attributed to the variation in soil N availability,resulting in a higher decomposition rate and a considerable decline in soil organic C (SOC) levels due to increased soil CO2 emissions,degraded soil quality,and increased atmospheric CO2 concentrations,leading to climate warming.Predicted climate warming is proposed to enhance SOC decomposition,which may further increase soil N availability,leading to higher soil CO2 efflux.However,a literature survey revealed that soil may also act as a potential C sink,if we could manage soil inorganic N pools and link microbial processes properly.Studies also indicated that the relative,rather than the absolute,availability of inorganic N pools might be of key importance under changing climate,as these N pools are variably affected by moisture-temperature interactions,and they have variable impacts on SOC turnover.Therefore,multi-factorial studies are required to understand how the relative availability of inorganic N pools and associated microbial processes may determine SOC dynamics for improved soil C management.  相似文献   
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A novel bioaugmented organic amendment (SFOA) [consisted of vermicompost (pre‐enriched with plant growth promoting fungi) mixed with pressmud and Azadirachta indica (A. Juss.) seed cake] was developed to reclaim sodic soil and support wheat production. A field trial of the SFOA application with/without chemical fertilizers conducted in completely randomized design with four replications to compare growth, yield and seed protein contents of wheat (Triticum aestivum L.) on sodic soil. The favourable changes occurred in different properties of amended soils were studied. A combined application of chemical fertilizer and SFOA significantly (p < 0·05) increased the number of spikelet per plant (63%) and weight of grains per ear (65%) in the amended soil compared with the control. Likewise, the grain yield, weight of 1000 grains and seed protein contents of wheat were significantly (p < 0·05) increased in the combined application compared with other treatments. The expression of protein bands with molecular weights of 36, 52 and 66 kDa were higher in seeds of wheat under the combined treatment. The improvement in wheat production was attributed to significant favourable changes in different soil characteristics such as bulk density, total organic C, alkaline phosphatase, β‐glucosidase, dehydrogenase and cellulase activities that were increased by 234%, 181%, 234%, 176%, 189% and 150%, respectively, in case of amended soil under the combined treatment compared with the control. The tested SFOA may be recommended as soil amendment for reclaiming sodic soil and supporting wheat cultivation with better crop growth and yield in combination with chemical fertilizers on sodic soil. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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ABSTRACT:   In order to elucidate the mechanism of the changes in gel forming characteristics of fish meat by pH-lowering, the gelation-temperature curve and the gelation-moisture content curve were examined using the acidified walleye pollack surimi or neutralized one after acidification. In the gelation-temperature curve, the gel strength was highest at 30°C and lowest at approximately 50–60°C, irrespective of pH shifting. The gel strength at 30°C and 80°C decreased with the decrease in pH value. The neutralization of acidified surimi improved the gel strength, but it was considerably lower than the original gel strength. The gel strength at 50–60°C was not affected by pH lowering. The gel strength at 80°C could not be revived to the original by pH readjustment, either in the presence or in the absence of EDTA. These results suggest that irreversible changes of meat protein take place under the low pH, and the oxidation ability of sulfhydryl (SH) groups of protein molecule is not affected by pH-shifting.  相似文献   
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A field experiment was conducted to evaluate the effect of different plant growth promoting microorganisms (PGPM) on micronutrient enrichment of rice crops grown under conventional (flooded) and SRI (System of Rice Intensification) practices. Significant differences were recorded among treatments and cultivation practices in terms of soil microbial activity reflected in enhanced nutrient uptake, enzyme activity, and yield. The Anabaena-based biofilm inoculants were particularly superior under both methods of cultivation, leading to 13–46% enhancement of iron and 15-41% enhancement of zinc in rice grains over uninoculated controls. SRI was found to be superior in terms of enhancing the concentration of zinc, copper, iron, and manganese (Zn, Cu, Fe and Mn), particularly in grains, and significant in increasing the activity of defense- and pathogenesis- related enzymes and yield parameters. This study illustrates the utility of cyanobacteria-based inoculants for both methods of rice cultivation and their significant interactions with the plant, leading to micronutrient enrichment of rice grains. Such formulations can complement the current biofortification strategies and help in combating the problems of malnutrition globally.  相似文献   
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