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51.
Soil organic carbon(SOC) and nitrogen(N) mineralization are important biogeochemical processes associated with soil fertility. These processes are influenced by physically, chemically, and biologically stabilized SOC fractions, the mechanisms of which are not well known. The present study was conducted to evaluate the combined effect of manure and mineral fertilizers on the contents of SOC fractions to promote the mineralization of SOC and N.Treatments included: i) no fertilizer control(CK); ii)...  相似文献   
52.
Stream salinity management is of prime importance for ensuring environmental sustainability of rivers, streams, lakes and other water bodies. Saline groundwater inflows are the main cause of deteriorating quality of stream flows; especially during periods of low flows. The Murray-Darling Basin is a good example for reducing groundwater recharge from irrigated agricultural areas with successful implementation of land and water management plans (LWMPs). In most cases, these plans help minimize the influence of saline groundwater flows on the stream salinity, as a preventive measure. As a remedial measure, this paper introduces a simple but an innovative approach for regulating saline groundwater inflows to natural streams in irrigated agricultural areas. The approach uses the flap gate with an automatic lowering and raising mechanism. During low stream flow, this gate is kept in a raised position. Depending upon the upstream inflows, the ponding situation will develop hydraulic gradient away from the stream; groundwater inflows to the creek will become minimal. During high stream flows, the gate is kept in a lower position to let the diluted water flows through the stream uninterrupted. To install, operate and manage such gates on multiple sites along the stream(s), the individual control panels can be joined into a central control station via telemetric link up. This approach, which holds a key for successfully regulating groundwater induced salinity to natural streams, should be considered in conjunction with other LWMPs to improve stream salinity in an irrigated agricultural area.  相似文献   
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54.
Ethnomedicinal uses, chemical composition (major nutrients, essential/toxic metals, phytochemical constituents), and antioxidant properties of the fruits of five Morus species (M. alba, M. laevigata, M. macroura, M. nigra, and M. serrata) were evaluated in this study. Standard methodology was used for the analysis of the nutrients, major/trace metals, phytochemicals, and antioxidant potential of the fruits. Highest average contents of the proteins (13.1%), fats (12.4%), fibers (8.02%), and carbohydrates (80.5%) were found in M. macroura, M. laevigata, M. nigra, and M. serrata, respectively. Among the metals, highest concentration in the fruits was shown by K (1080–1230 mg/kg), followed by Mg (84.4–207 mg/kg), Ca (54.8–146 mg/kg), Fe (13.6–59.0 mg/kg), Na (5.43–14.8 mg/kg), and Zn (2.15–5.57 mg/kg). The phytochemicals and antioxidant activities were measured in the water and acetone extracts of the fruits. Relatively higher total phenolics (85.6 mg GAE/100 g, FW), flavonoids (85.8 mg RE/100 g, FW), flavonols (99.8 mg RE/100 g, FW), and ascorbic acid (4.12 mg AAE/100 g, FW) contents were found in M. nigra, which also revealed significantly higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition (93.8%). Considerably higher OH radical and H2O2 scavenging activities were observed in M. macroura and M. alba, respectively. Comparatively higher ferrous ions chelating activity (37.8%) was noted in M. serrata, which also showed highest value for phosphomolybdenum assay (183 µM AAE/100 g, FW). Highest ferric ion reducing antioxidant power (69.9 µM GAE/100 g, FW) was found in M. leavigata. The Morus fruits were a good source of the nutrients, minerals, and phyotchemicals along with superior antioxidant potential. Health risk assessment showed no significant non-carcinogenic or carcinogenic health risk associated with the consumption of these fruits.  相似文献   
55.

Purpose  

To evaluate a 3% solution of household detergent viz., Surf Excel (Surf field mastitis test, SFMT) vis-à-vis California mastitis test (CMT), Whiteside test (WST), somatic cell counts (SCC; cut off limit = 5 × 105 cells per millilitre) and bacteriological cultures for the detection of subclinical mastitis in quarter foremilk samples (n = 800) of dairy cows and buffaloes.  相似文献   
56.
Onion is one of the major vegetable crops in terms of production as well as consumption. In the current research, available onion genetic stock was evaluated to identify male-sterile lines and produce high-yielding F1 hybrids for future breeding programmes. A mitochondrial DNA-based marker was mapped and correlated with phenotypic traits to isolate male-sterile plants. Based on the floral and pollen structure, nine putative male-sterile lines were identified. On the other hand, for nuclear marker identification at Ms locus, two sets of primers were used, one for Ms dominant allele and another for sterile and maintainer plants. Results revealed that 70% of open pollinated varieties (OPVs) possess plants with sterile cytoplasm coupled with genetic sterility at Ms locus, called sterile “A” line. Approximately 20% of plants in some genotypes were identified with normal (N) cytoplasm having recessive fertility gene at Ms locus, called maintainer “B” line. Based on the present findings, “A”, “B” and “R” (restorer line), future F1 hybrid seed production systems in onion is discussed.  相似文献   
57.
1. Escherichia coli is one of the most common facultative anaerobic species present in the gastrointestinal tract of animals and human beings. Usually they occur as commensals, but some serotypes can cause significant illnesses in humans as well as mammals and birds.

2. The occurrence of E. coli in different categories of table eggs collected from markets was evaluated. Isolates were analysed for the presence of virulence genes, antibiotic susceptibility pattern and efficacy of peracetic acid and chlorine for the purpose of decontaminating table eggs.

3. Significant differences were observed in the occurrence of E. coli between different groups viz. processed (cleaned, washed, sanitised and packed eggs), unprocessed (un-cleaned, un-sanitised and loose eggs) and free range (eggs obtained from backyard poultry) table eggs. Overall, E. coli occurred in table eggs at 28.6% with 22.9, 29.2 and 50.0% occurrence in processed, unprocessed and free-range table eggs, respectively.

4. A total of 24 isolates of E. coli were obtained and screened for virulence genes viz. STH, SLT1/2 and INVE genes. Of the 24 isolates recovered, 10 typeable isolates belonged to O141, O119, O9, O120 and O101 serotypes, while the remaining 14 were untypeable. Antibiograms of the isolates showed multiple antimicrobial resistance (MAR) index in the range of 0.13–0.40.

5. Peracetic acid (PAA) and chlorine (CL) were studied for their sanitisation efficacy; concentrations of 100 mg/kg of PAA and 200 mg/kg of CL completely inactivated E. coli over the egg surface and also resulted in 2.58 and 2.38 log reduction in total viable counts (TVC), respectively.

6. The presence of virulence-associated shiga-like toxin (SLT1/2) and invasion E (INVE) genes and antimicrobial resistance among the emerging serotypes of pathogenic E. coli isolated from table eggs has public health implications. It underscores the need to implement better management practices across the production systems and marketing channels to produce E. coli-free wholesome eggs for consumers.  相似文献   

58.
This study was conducted to assess the efficacy of bio-organic phosphate (BOP) and diammonium phosphate (DAP) fertilizers for improving the growth, yield, plant phosphorus (P) content and profitability of wheat cultivation under systems of wheat intensification (direct seeding and nursery transplantation) and conventional sowing (broadcasting). BOP was formulated by enriching the compost with rock phosphate and inoculated with plant growth-promoting rhizobacterial (PGPR) strain, Bacillus thuringiensis strain K5. Results revealed the supremacy of BOP over DAP, and the direct seeding method over the other sowing methods in almost all parameters studied. The application of BOP significantly (p ≤ 0.05) increased the plant height, root length, number of tillers per plant, wheat biomass, number of grains per spike, 1000-grain weight, grain yield, straw and grain P contents in direct seeded wheat in comparison to DAP fertilization. Furthermore, application of BOP and direct seeding of wheat generated more profit per hectare compared with the other treatments.  相似文献   
59.
60.
Phosphorous (P) and zinc (Zn) are plant nutrients that interact with each other in soil–plant systems. Such interactions may cause deficiency of one of the nutrients interacting with each other if interactions are antagonistic. In the present trial, a field experiment was conducted to investigate the interactive effect of Zn (0 and 16 kg ha?1) and P (0 and 60 kg ha?1) on growth, yield and grain Zn concentration of two maize (Zea mays L.) genotypes, i.e., Neelam (local) and DK‐6142 (hybrid). Growth and yield of both maize genotypes were increased by the application of Zn and P treatments compared with control, but Zn+P was more effective than their sole application. When compared to control, combined application of Zn+P increased grain Zn and P concentrations by 52% and 32%, respectively, averaged for the two genotypes. Single application of P decreased grain Zn concentration by 10% over control. Application of P and Zn particularly in combination decreased the grain [phytate] : [Zn] ratio and increased the estimated human Zn bioavailability in grains based on a trivariate model of Zn absorption in both maize genotypes. Conclusively, combined Zn+P application appeared more suitable for enhancing grain yield and agronomic Zn biofortification in maize grains. However, Zn fertilization aiming at increasing grain yield and grain Zn concentration should consider the genotypic variations and P rate.  相似文献   
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