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291.
Field experiments evaluated the effects of integrated nutrient management on symbiotic parameters, growth, nutrient accumulation, productivity and profitability of lentil (Lens culinaris Medikus). Application of recommended dose of nutrients (RDN, 12.5 kg N ha?1 + 40 kg P2O5 ha?1) + 25 kg ZnSO4 ha?1 + seed inoculation with biofertilizers [Rhizobium + phosphate solubilizing bacteria (PSB) + plant growth promoting rhizobacteria (PGPR)] + 1.0 g ammonium molybdate kg?1 seed recorded the highest number & dry weight of nodules, leghaemoglobin content, root & shoot dry weight, plant height, number of pods plant?1 and 100-seed weight. The next best treatment was RDN + seed inoculation with biofertilizers + 1.0 g ammonium molybdate kg?1 seed. On the basis of mean of three-year data, the treatment of RDN + 25 kg ZnSO4 ha?1 + seed inoculation with biofertilizers 1.0 g ammonium molybdate kg?1 seed proved the best in realizing the highest grain yield (34.0%), gross returns (34.0%) and net returns (54.8% higher over control). Nitrogen, phosphorus and potassium in the grains and straw were significantly improved where RDN was applied in combination with seed inoculation, basal application of ZnSO4 and seed treatment with 1 g ammonium molybdate than their single applications.  相似文献   
292.
Experiments were conducted to study drainage and runoff losses of selenium (Se) from two seleniferous soils (from Simbly containing total Se 850 μg [kg soil]–1 and from Barwa containing 1310 μg [kg soil]–1) under simulated rainfall (250–260 mm in three rainstorms) conditions. Rainfall intensities ranged from 56 to 120 mm h–1 with uniformity coefficients ranging from 70.6% to 84.2%. Selenium lost through drainage (sum of drainage from initially saturated soil for 24 h and through dry and wet runs) was 0.15% and 0.11% of total Se content in the two soils. In soils having similar pH and organic‐C content, losses of Se through drainage as well as runoff were defined by total Se, water‐soluble Se, CaCO3 content, and texture of the soils. The amount of runoff water was almost two times in the soil with fine texture and less infiltration rate than in the other and that same trend was observed with respect to loss of sediment. The soil with higher CaCO3 content and water‐soluble Se lost more Se with moving water both through leaching and runoff, whereas the other soil with fine texture lost greater amount of Se with the sediment. Total Se lost through drainage as well as runoff was 0.29% of the native Se present in both the soils suggesting that significant amount of Se could be lost from seleniferous soils during irrigation and rainfall events.  相似文献   
293.
Pharmacokinetic (PK)–pharmacodynamic (PD) integration of crystalline ceftiofur‐free acid (CCFA) was established in six healthy female goats administered subcutaneously (s.c.) on the left side of the neck at a dosage of 6.6 mg/kg body weight. Serum concentrations of ceftiofur and desfuroylceftiofur (DFC) were determined using high‐performance liquid chromatography. Mutant prevention concentration (MPC), minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ceftiofur were determined for Pasteurella (P.) multocida. Mean terminal half‐life and mean residence time of ceftiofur + DFC were 48.6 h and 104 h, respectively. In vitro plasma protein binding of ceftiofur was 46.6% in goats. The MIC and MBC values of ceftiofur were similar in serum and MHB and a very small difference between these values confirmed bactericidal activity of drug against P. multocida. In vitro and ex vivo time–kill curves for P. multocida demonstrated a time‐dependent killing action of drug. Considering target serum concentration of 0.20 μg/mL, PK‐PD values for AUC24 h/MIC90 and T > MIC90, respectively, were 302 h and 192 h against P. multocida. A MPC/MIC ratio of 10–14 indicated that selective pressure for proliferation of resistant mutants of P. multocida is minimal after CCFA single‐dose administration. Based on MPC = 1.40 μg/mL for P. multocida, the PK‐PD indices, viz. T > MPC and AUC24/MPC, were 48 h and 43 h, respectively. The data suggested the use of single dose (6.6 mg/kg, s.c.) of CCFA in goats to obtain clinical and bacteriological cure of pneumonia due to P. multocida.  相似文献   
294.
Genotypic variation for morpho-physiological parameters, phosphorus (P) content and root acid phosphatase activity was studied in 52 pigeonpea genotypes. Data related to shoot (length, dry weight, number of leaves, and leaf area), root (volume, length, dry weight, area, perimeter, and number of root tips), acid phosphatase activity, and P content (root, stem, and leaf) were recorded at 60 days after sowing (DAS). The P use efficient genotypes showed high root length, root area, root perimeter, root dry weight, P content in leaves, and root to shoot dry weight ratio under the P not added condition. Significant variation was found among genotypes for root- and shoot-associated characteristics under both P treatments. The P use efficient genotypes with improved root morphological phenes have potential to acquire and utilize more P from immobile soil bound P sources may be of additional factor for increasing efficiency of acquisition and utilization of supplied P fertilizer.  相似文献   
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