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51.
Organic fractions from farm yard manure (FYM), vermicompost, municipal sludge, mustard cake, and surface soil of West Bengal, which was arsenic (As)-contaminated, were extracted and fractionated into fulvic and humic acid (FA and HA, respectively) fractions following standard procedures. These HA and FA samples were characterized by pH-potentiometric titrations, viscometric measurements and visible spectrophotometry. The stability constant (logK) of the complexes formed by these natural with As in aqueous phase was evaluated by the ion-exchange method. The logK values suggest that the organo-As complexes were quite stable. The release isotherm of As from the HA/FA complexes extracted from vermicompost and FYM was assayed in the presence of molybdate, nitrate, phosphate, sulfate and borate. The greatest tendency to displace As from the complexes was shown by sulfate, molybdite, and nitrate.  相似文献   
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E. S. Rao  A. D. Munshi  P. Sinha  Rajkumar 《Euphytica》2008,159(1-2):123-134
A study was conducted to understand the genetics of rate limiting disease reaction to Alternaria solani in tomato. The results from χ2 analysis and Castle Wright estimation revealed that resistance is an oligogenic character controlled by two to few genes. In general, the results for predominant gene effects reveal that both additive and non-additive effects are involved in the inheritance of early blight resistance. The results for predominant gene effects obtained for various crosses studied are discussed along with their implications for improvement of this trait.  相似文献   
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BACKGROUND: An efficient delivery system for seed‐protectant chemicals is needed in light of several disadvantages of conventional seed treatment methods. This study evaluates the efficacy of film‐coat application in maintaining the persistence and potency of imidacloprid on Lycopersicon esculentum (L.) Mill. seeds after simultaneous storage under ambient and regulated environment in paper and aluminium packages. RESULTS: High‐performance liquid chromatography (HPLC) revealed 0.135 mg kg?1 of herbage material to be the threshold value beyond which absolute control was obtained, and with film coating the latter was achieved even with half‐dosage seed treatment, irrespective of the storage condition. The technique provided early protection to the crop and also nullified the deleterious effects of ambient storage on the persistence and potency of the pesticide. CONCLUSION: Film coating enabled superior pesticide dosage as well as higher biological efficacy to be achieved. Hence, in addition to being an ecofriendly alternative, the technique would be a more economically viable option for storage of treated seeds. Copyright © 2009 Society of Chemical Industry  相似文献   
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The histochemical ATPase method for muscle fibre typing was first described by Brooke and Kaiser in 1970. However, problems have been found with the subdivision of type II fibres using this technique. To determine whether indirect myosin immunocytochemistry using anti-slow (5-4D), anti-fast (1A10) and anti-fast red (5-2B) monoclonal antibodies with cross reactivity for type I, II and IIa fibres, respectively, in a number of species, could identify three fibre types in equine skeletal muscle, data on fibre type composition and fibre size obtained using the two different techniques were compared. Results indicate that different myosin heavy chains can coexist in single equine muscle fibres. Type I and type II fibres were identified by immunocytochemistry, but subdivision of type II fibres was not possible. Although the percentage of type I and type II fibres was not significantly different for the two techniques, a few fibres reacted with both the 1A10 and 5-4D antibodies.  相似文献   
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Acaciaside A and B, two acylated bisglycoside saponins originally isolated from the funicles of Acacia auriculiformis, are known to have antihelminthic activity. Their antifungal and antibacterial activities were investigated. Complete inhibition of conidial germination of Aspergillus ochraceous and Curvularia lunata was recorded at 300 microg/ml or less whereas to inhibit the growth of Bacillus megaterium, Salmonella typhimurium and Pseudomonas aeruginosa 700 microg/ml or higher concentrations of the mixture was required. Two catabolic enzymes, phosphofructokinase and isocitrate dehydrogenase, responded differentially in fungi and bacteria against sublethal concentrations of the compound when assayed from their cell free extracts. An increased specific activity of the enzymes in bacteria and a decrease activity in fungi indicate a possible different mechanism of inhibition of saponins on the organisms tested.  相似文献   
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Phytate formed during maturation of plant seeds and grains is a common constituent of plant-derived fish feed. Phytate-bound phosphorus (P) is not available to gastric or agastric fish. A major concern about the presence of phytate in the aquafeed is its negative effect on growth performance, nutrient and energy utilization, and mineral uptake. Bound phytate-P, can be effectively converted to available-P by phytase. During the last decade, phytase has been used by aqua feed industries to enhance the growth performance, nutrient utilization and bioavailability of macro and micro minerals in fish and also to reduce the P pollution into the aquatic environment. Phytase activity is highly dependent on the pH of the fish gut. Unlike mammals, fish are either gastric or agastric, and hence, the action of dietary phytase varies from species to species. In comparison to poultry and swine production, the use of phytase in fish feed is still in an unproven stage. This review discusses effects of phytate on fish, dephytinisation processes, phytase and pathway for phytate degradation, phytase production systems, mode of phytase application, bioefficacy of phytase, effects of phytase on growth performance, nutrient utilization and aquatic environment pollution, and optimum dosage of phytase in fish diets.  相似文献   
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