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1.
  • Terminal drought substantially reduces chickpea yield. Reducing water use at vegetative stage by reducing transpiration under high vapor pressure deficit (VPD), i.e. under dry/hot conditions, contributes to drought adaptation. We hypothesized that this trait could relate to differences in a genotype's dependence on root water transport pathways and hydraulics.
  • Transpiration rate responses in conservative and profligate chickpea genotypes were evaluated under increasing VPD in the presence/absence of apoplastic and cell‐to‐cell transport inhibitors.
  • Conservative genotypes ICC 4958 and ICC 8058 restricted transpiration under high VPD compared to the profligate genotypes ICC 14799 and ICC 867. Profligate genotypes were more affected by aquaporin inhibition of the cell‐to‐cell pathway than conservative genotypes, as measured by the root hydraulic conductance and transpiration under high VPD. Aquaporin inhibitor treatment also led to a larger reduction in root hydraulic conductivity in profligate than in conservative genotypes. In contrast, blockage of the apoplastic pathway in roots decreased transpiration more in conservative than in profligate genotypes. Interestingly, conservative genotypes had high early vigour, whereas profligate genotypes had low early vigour.
  • In conclusion, profligate genotypes depend more on the cell‐to‐cell pathway, which might explain their higher root hydraulic conductivity, whereas water‐saving by restricting transpiration led to higher dependence on the apoplastic pathway. This opens the possibility to screen for conservative or profligate chickpea phenotypes using inhibitors, itself opening to the search of the genetic basis of these differences.
  相似文献   
2.
In soil biota, higher and enduring concentration of heavy metals like cadmium (Cd) is hazardous and associated with great loss in growth, yield, and quality parameters of most of the crop plants. Recently, in-situ applications of eco-friendly stabilizing agents in the form of organic modifications have been utilized to mitigate the adverse effects of Cd-toxicity. This controlled experiment was laid down to appraise the imprints of various applied organic amendments namely poultry manure (PM), farmyard manure (FYM), and sugarcane press mud (PS) to immobilize Cd in polluted soil. Moreover, phytoavailability of Cd in wheat was also accessed under an alkaline environment. Results revealed that the addition of FYM (5–10 ton ha-1 ) in Cd-contaminated soil significantly increased germination rate, leaf chlorophyll content, plant height, spike length, biological and grain yield amongst all applied organic amendments. Moreover, the addition of FYM (5–10 ton ha-1 ) also reduced the phytoavailability of Cd by 73–85% in the roots, 57–83% in the shoots, and 81–90% in grains of wheat crop. Thus, it is affirmed that incorporation of FYM (5–10 ton ha-1 ) performed better to enhance wheat growth and yield by remediating Cd. Thus, the application of FYM (5–10 ton ha-1 ) reduced the toxicity induced by Cd to plants by declining its uptake and translocation as compared to all other applied organic amendments to immobilize Cd under sandy alkaline polluted soil.  相似文献   
3.
This work aimed at investigating the potential modulatory effects and mechanisms of crocin against CCl4‐induced nephrotoxicity. Forty male rats were allocated for three weeks treatment with corn oil, CCl4, crocin, or crocin plus CCl4. Crocin effectively mitigated CCl4‐induced kidney injury as evidenced by amelioration of alterations in kidney histopathology, renal weight/100 g body weight ratio and kidney functions. Crocin modulated CCl4‐induced disturbance of kidney cytochrom‐P450 subfamily 2E1 and glutathione‐S‐transferase. The attenuation of crocin to kidney injury was also associated with suppression of oxidative stress via reduction of lipid peroxides along with induction of renal glutathione content and enhancement of superoxide dismutase, glutathione peroxidase, and catalase activities. Crocin mitigated CCl4‐induced elevation of the renal levels of tumor necrosis factor‐alpha, interleukin‐6, prostaglandin E2, and active caspases‐3. Collectively, crocin alleviated CCl4‐induced renal damage via modulation of kidney metabolizing enzymes, suppression of oxidative stress, inhibition of inflammatory cytokines, PGE2, and active caspase3 in kidney.  相似文献   
4.
Stress has many biological effects on human daily life. In the present study, dietary protein intake was correlated with the investigated stress levels of nurses and housewives of the targeted urban population. Age group ranged from 30 to 45 years and both the groups belonged to middle socioeconomic status. After calculations of environmental, psychological and physiological stresses, it was observed that the levels of stress in housewives were significantly higher than those of nurses. Recommended dietary allowances, RDA and actual protein intakes, API were also compared in both the groups. The found protein intake was less in housewives as compared to that of nurses.  相似文献   
5.
一株蓝麻黄内生放线菌的分离、鉴定和活性研究   总被引:1,自引:0,他引:1  
目的:分离对农作物致病菌具有拮抗作用的株内生放线菌,并对其进行系统鉴定.方法:经表面消毒采用研磨法从蓝麻黄中分离内生放线菌;再通过琼脂扩散法筛选具有抗农作物致病菌活性的内生放线菌;利用菌株形态特征、培养特征、生理生化特性和16S rRNA序列分析对拮抗菌进行鉴定;并对代谢产物做了生物碱的检测.结果:从蓝麻黄中分离到菌7株内生放线菌而其中的XJEG-GA-16具有较好拮抗作用,该菌对7种植物病原菌具有较好的拮抗作用,尤其是对玉米大斑病菌的拮抗作用显著抑菌圈大于20mm.经形态学观察,培养特征、生理生化特和分子分类学分析鉴定与Streptomyces albus subsp.albus在同一个分支上,同源性为99%.该菌株代谢产物中含有生物碱.结论:蓝麻黄内生放线菌XJEG-GA-16对农作物致病菌有明显的拮抗作用,最终鉴定为链霉菌Streptomyces albus subsp.Albus.  相似文献   
6.
Urban expansion can be seen as the most pervasive human impact on the environment where its high resource use contributes negatively to climate change and resource scarcity crises. Many experts call for decoupling resource use, economic development, and related urban development especially within cities of the Global South. This paper focuses on investigating resource efficiency through the lens of urban metabolism. It investigates current resource flows, through material flow analysis, from source to sink, in two diverse districts in Cairo: a formal district and an informal one, regarding materials (waste) and mobility. Consequently, the paper discusses locally responsive interventions that address local priorities as opposing to citywide one‐size fits all solution. The paper relies on parcel audits, which are embedded in an Urban Metabolism Information System developed by the Ecocity Builders and their partners, through a joint project with Cairo University. The methodology couples crowd‐sourced data, parcel audits, and experts’ knowledge to better understand resource flows based on a bottom‐up approach, given the unavailability of governmental data on the local level. The paper further correlates the perceived quality of life with the actual resource flows. It utilizes fieldwork investigations to argue against the local misconceptions regarding the inefficiency of informal areas/systems versus the higher efficiency of planned areas/systems. The paper concludes by proposing integrated solutions that respond to local needs and resources. It highlights the challenges and lessons of this tailored bottom‐up approach and its applicability in other cities worldwide.  相似文献   
7.
Glenoid prosthesis loosening is the most common cause for revision total shoulder arthroplasty. Stress-induced bone remodeling may compromise long-term prosthesis fixation and significantly contribute to loosening. Realistic, robust analysis of bone-prosthesis constructs need to look beyond initial post-implantation mechanics provided by static finite element (FE) simulation. Adaptive bone remodeling simulations based on Wolff's law are needed for evaluating long-term glenoid prostheses fixation. The purpose of this study was to take a first step towards this goal and create and validate two-dimensional FE simulations, using the intact glenoid, for computing subject-specific adaptive glenoid remodeling. Two-dimensional glenoid FE models were created from scapulae computed tomography images. Two distinct processes, “element” and “node” simulations, used the forward-Euler method to compute bone remodeling. Initial bone density was homogeneous. Center and offset load combinations were iteratively applied. To validate the simulations we performed location-specific statistical comparisons between predicted and actual bone density, load combinations, and “element” and “node” processes. Visually and quantitatively “element” simulations produced better results (p>0.22), and correlation coefficients ranged 0.51–0.69 (p<0.001). Having met this initial work's goals, we expect subject-specific FE glenoid bone remodeling simulations together with static FE stress analyses to be effective tools for designing and evaluating glenoid prostheses.  相似文献   
8.
Cell capacity for cytosolic NADPH regeneration by NADP‐dehydrogenases was investigated in the leaves of two hybrid poplar (Populus deltoides × Populus nigra) genotypes in response to ozone (O3) treatment (120 ppb for 17 days). Two genotypes with differential O3 sensitivity were selected, based on visual symptoms and fallen leaves: Robusta (sensitive) and Carpaccio (tolerant). The estimated O3 flux (POD0), that entered the leaves, was similar for the two genotypes throughout the treatment. In response to that foliar O3 flux, CO2 assimilation was inhibited to the same extent for the two genotypes, which could be explained by a decrease in Rubisco (EC 4.1.1.39) activity. Conversely, an increase in PEPC (EC 4.1.1.31) activity was observed, together with the activation of certain cytosolic NADP‐dehydrogenases above their constitutive level, i.e. NADP‐G6PDH (EC 1.1.1.49), NADP‐ME (malic enzyme) (EC 1.1.1.40) and NADP‐ICDH (NADP‐isocitrate dehydrogenase) (EC1.1.1.42). However, the activity of non‐phosphorylating NADP‐GAPDH (EC 1.2.1.9) remained unchanged. From the 11th fumigation day, NADP‐G6PDH and NADP‐ME profiles made it possible to differentiate between the two genotypes, with a higher activity in Carpaccio than in Robusta. At the same time, Carpaccio was able to maintain high levels of NADPH in the cells, while NADPH levels decreased in Robusta O3‐treated leaves. All these results support the hypothesis that the capacity for cells to regenerate the reducing power, especially the cytosolic NADPH pool, contributes to improve tolerance to high ozone exposure.  相似文献   
9.
Solanum lycopersicum and Solanum tuberosum are agriculturally important crop species as they are rich sources of starch, protein, antioxidants, lycopene, beta-carotene, vitamin C, and fiber. The genomes of S. lycopersicum and S. tuberosum are currently available. However the linear strings of nucleotides that together comprise a genome sequence are of limited significance by themselves. Computational and bioinformatics approaches can be used to exploit the genomes for fundamental research for improving their varieties. The comparative genome analysis, Pfam analysis of predicted reviewed paralogous proteins was performed. It was found that S. lycopersicum proteins belong to more families, domains and clans in comparison with S. tuberosum. It was also found that mostly intergenic regions are conserved in two genomes followed by exons, intron and UTR. This can be exploited to predict regions between genomes that are similar to each other and to study the evolutionary relationship between two genomes, leading towards the development of disease resistance, stress tolerance and improved varieties of tomato.  相似文献   
10.
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