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1.
Salinity is a major abiotic stress that affects crop production throughout the world. Biochar is an activated carbon soil conditioner that can alleviate the negative impacts of salinity. The research was conducted to evaluate the ameliorative effect of 1% and 2% of biochar application on wheat seed germination and growth attributes under salinity. Both levels of biochar improved the germination and growth conditions under salinity; however, 2% biochar level was more effective compared to 1% level. Root and shoot length increased up to 23% and11% with 2% biochar, respectively. The maximum increase of 16% and 10% in leaf water potential and osmotic potential was noted with 2% biochar at 150 mM salt. The decrease in proline content and soluble sugar at 2% biochar was 51% and 27%, respectively. Decrease in superoxide dismutase activity was 15.3% at 2% level of biochar under stress biochar mitigates the negative effects of salinity and improved wheat productivity.  相似文献   
2.
Journal of Soils and Sediments - Compression studies can provide insights into evaluating the engineering potential and environmental impact of clay. The objective of this study was to...  相似文献   
3.
Zizyphus oxyphylla Edgew is used in Pakistan as a folk medicinal remedy for inflammatory conditions, pains especially rheumatic pain, fevers, allergy and diabetes. The aim of the current study was to scientifically validate the folk use of Z. oxyphylla Edgew by using the isolated compound in vitro and in vivo levels. Kushecarpin A was isolated from ethyl acetate fraction of the plant crude extract. Molecular docking simulations predicted Kushecarpin A as a potential new lipoxygenase (LOX) inhibitor. Kushecarpin A showed significant lipoxygenase inhibition (IC50: 7.2 ± 0.02 μM) thus validated computational prediction. It also exhibited significant and highly significant inhibition (p < 0.05 and p < 0.01) of carrageenan-induced hind paw oedema at the doses of 5, 10 and 20 mg/kg. Kushecarpin A seems to be a potentially new anti-inflammatory compound responsible for anti-inflammatory activities of Z. oxyphylla Edgew. In vitro and in vivo anti-inflammatory inflammatory activities were found in good agreement with the folk medicinal use of Z. oxyphylla Edgew in inflammatory disorders.  相似文献   
4.
A new taxoid Taxawallin I (1) along with two known taxoids (2-3) were isolated from methanolic bark extract of Taxus wallichiana Zucc. Structural characterization was confirmed by mass and NMR spectral techniques. Taxawallin I exhibited significant in-vitro anticancer activity against HepG2, A498, NCI-H226 and MDR 2780AD cancer lines. Tubulin binding assay was performed to assess its tubulin binding activity. Molecular docking analysis was performed to study the potential binding mode inside the taxol binding site of β-tubulin.  相似文献   
5.
Under the umbrella of WTO, the reduction in trade barriers has forced the policy makers to focus on the export competitiveness. Rice is an important source for foreign exchange earnings for the economy of Pakistan, keeping in mind of this fact, the competitiveness of Pakistan’s rice with other major exporters was examined by applying revealed competitive advantage. The domestic consumption trends of rice among the major rice exporting countries were also analyzed in the current study. The results revealed that as compare to other major exporters of rice in the world, Pakistan had high competitive and comparative advantage in the production of rice. The comparison of the movements in comparative advantage indices for Pakistan with the major world rice competitors/exporters showed that Pakistan possessed relatively high comparative and competitive advantages in rice production. The declining domestic per capita consumption of rice and increasing trends in competitiveness for Pakistan clearly revealed the expected potential of higher growth which meant that rice exports from Pakistan could continue to play an important role for the earnings of foreign exchange. In order to exploit the potential benefits of rice exports, we need to strengthen the competitiveness in rice sector of Pakistan.  相似文献   
6.
The research work was carried out to synthesize a series of novel chitosan based water dispersible polyurethanes (CS-WDPUs). The three step synthesis involves the formation of end capped PU-prepolymer was formed through the reaction between polyethylene glycol (PEG) (Mn=600 g/mole, dimethylolpropionic acid (DMPA) and isophorone diisocyanate (IPDI) followed by the preparation of neutralized NCO terminated PU-prepolymer, which lead to the chain extension by using the chitosan. The dispersion of the obtained product was carried out by adding proper proportion of water. The synthesized CS-WDPUs were applied onto the different qualities of plain weave poly-cotton printed and dyed textile swatches by employing pad-dry-cure procedures. The textile assets of the treated and untreated textile swatches were assessed, as color fastness, pilling resistance, tear and tensile strength. The results showed that the chitosan incorporation into PU backbone has significant effect on the assets of treated textiles. These synthesized CS-WDPUs are eco-friendly bio-based finishes with potential applications for polyester/cotton textiles.  相似文献   
7.
The study presents the first report on biocontrol of brown sheath rot disease of rice caused by Pseudomonas fuscovaginae using rhizo-bacterial isolate Bacillus amyloliquefaciens Bk7. Four potential bioactive antagonists were selected from 120 Bacillus isolates. Results obtained from in vitro laboratory assay showed that rhizosphere bacterial strain Bk7 and its metabolites significantly suppressed the growth of Pseudomonas fuscovaginae with 93 % efficacy. In glasshouse experiments, strain Bk7 exhibited biocontrol efficacy of 76.6 % by reducing the disease incidence to 16.9 %, compared to 72.8 % observed in control treatment. In addition, the isolate Bk7 showed the growth promotion efficacy of plant height (GPE, 46.4 %) and fresh weight (GPE, 84.3 %). Characterization of isolate Bk7 revealed its strong capability for biofilm formation, inorganic phosphate solubilization and production of high amounts of Indole-3 acetic acid, siderophores and ammonia in vitro. Results obtained from multiplex PCR assay confirmed the presence of five lipopeptide biosynthetic gene markers (srfAA, fenD, bmyB, bacA and ituC) in the genome of strain Bk7. Moreover, Real-time qPCR of these genes demonstrated that surfactin, iturin and bacylisin coding genes were highly expressed in response to P. fuscovaginae exposure in vitro. Rhizosphere bacterial strain Bk7 was identified as B. amyloliquefaciens strain Bk7 based on the analysis of 16S rDNA internal transcribed spacer sequences and a fatty acid methyl ester analysis. The results obtained from this study showed the potential usefulness of Bk7 as a biocontrol agent in disease control of rice brown sheath rot.  相似文献   
8.
The strain Rs-198 isolated from alkaline soil was investigated and identified as Pseudomonas putida on the basis of its physiological and biochemical properties as well as its 16S rDNA sequence analysis. The effects of the strain Rs-198 on cotton seedling growth under salt stress were studied. The results indicated that Rs-198 could protect against salt stress and promote cotton seedling growth. After treatment with Rs-198, the germination rate and healthy stand of cotton were increased by 23.8% and 30.7%, respectively. Individual plant height, fresh weight and dry weight of cotton seedling were increased by 12.8%, 30.7% and 10.0%, respectively as compared to the control (CK). In the fields, Rs-198 also exhibited the ability to increase the cotton's germination rate and healthy stand, which were 16.0% and 22.4% higher than that of CK. Further analysis showed that Rs-198 could increase the absorption of the Mg2+, K+ and Ca2+ and decrease the uptake of the Na+ from the soil and also improve the production of endogenous indole acetic acid (IAA) content and reduce the abscisic acid (ABA) content of cotton seedling under salt stress.  相似文献   
9.
Herbage growth and nitrogen (N) use efficiency in grazed or mown grasslands are generally low, associated mostly with poor response to fertilizer N. The aim of the present investigation was to examine the short-term response of grass to fertilizer N with respect to herbage yield and nitrogen use efficiency (NUE) in order to provide a better basis for improving the efficient use of fertilizer N in grassland ecosystems. Both NO3 ? and NH4 + sources of N were applied to an established grass sward with three moisture levels, i.e., natural conditions (63% water-filled pore space, WFPS), near field capacity level (71% WFPS), and slightly wetter than field capacity (84% WFPS). Herbage yield, i.e., dry matter (DM), N uptake, N recovery efficiency, yield efficiency, and physiological efficiency were determined over a 7–28 d period. Addition of N fertilizers significantly increased the herbage yield and N uptake of grass sward over that of the control. In the plots where NO3 ??N was added as the N source, DM yield was between 1760–1870 kg ha?1, N recovery efficiency was between 24%–43%, and yield and physiological efficiency were in the range of 2.1–3.2 and 6.4–8.8 kg DM kg? 1 N, respectively. In NH4 +?N added plots, the DM yield was between 3190–3700 kg ha? 1, N recovery efficiency was between 39%–48% while yield and physiological efficiency were in the range of 3.5–5.6 and 9.0–11.6 kg DM kg? 1 N, respectively. Results indicated that total DM yield, N uptake, and NUE depend on the source of N and the level of moisture in the field. Assimilation of N is also affected by the stage of plant development after N fertilization. About 50%–54% of applied N was recovered in the initial 14 and 21 d after fertilizer application and thereafter translocation of N slowed. A fall in herbage production and minimal response to N fertilizer has been observed at 84% WFPS, while the maximum herbage yield and N recovery efficiency was recorded in soil near or below field capacity. The grass sward with added NH4 +?N produced a larger yield and had higher NUE relative to the sward with NO3 ??N. Results confirm that applied N was not utilized efficiently by grass sward and a decrease in N uptake and its utilization seem to be the key factors responsible for the poor herbage productivity often observed in pastoral agriculture. These results suggest that both moisture and N source have a substantial effect on herbage yield and N utilization by plants and therefore should be considered for efficient management of N fertilization and recommendations for grass sward.  相似文献   
10.
Osteopontin gene is regarded as a plausible candidate in mammary gland differentiation and development, expressed by variety of cells, tissues, and biological fluids including milk. The current study was performed in two phases. In the first phase, Osteopontin gene polymorphisms were identified and associated with milk composition such as ash, milk fat, SNF, lactose, and protein. In the second phase, milk samples from five healthy mastitis-free Nili Ravi buffaloes were analyzed for expression of Osteopontin gene at transition (day 15), mid (day 90), and end (day 250) stage of their second lactation. Briefly, blood samples were collected from Nili Ravi buffalo to isolate the genomic DNA, specific primers were designed for PCR amplification. The amplified PCR products were sequenced bi-directionally. Six polymorphisms were identified in the coding region and four in the intronic region of the gene. The results showed that SNP g.38329758 T > C causing substitution of valine to alanine (V127A) was associated with high milk protein. For mRNA expression analysis, somatic cells were separated from milk samples for RNA isolation. Analysis of differential gene expression data has permitted us to illustrate the expression pattern of osteopontin gene in lactating buffalo. The Osteopontin gene was found to be transcribed among all three lactation stages, but expression was observed with the highest value (fold change) in peak lactation and remained elevated till the end of lactation. Identified gene marker may be helpful for the prediction of superior animal for selection. The presented study also gave an insight into the genetic screening and lactation biology of riverine buffalo, offering direction for future research in lactating buffalo.  相似文献   
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