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731.
Among grain legumes, faba bean is becoming increasingly popular in European agriculture due to recent economic and environmental
interests. Faba bean can be a highly productive crop, but it is sensitive to drought stress and yields can vary considerably
from season to season. Understanding the physiological basis of drought tolerance would indicate traits that can be used as
indirect selection criteria for the development of cultivars adapted to drought conditions. To assess genotypic variation
in physiological traits associated with drought tolerance in faba bean and to determine relationships among these attributes,
two pot experiments were established in a growth chamber using genetic materials that had previously been screened for drought
response in the field. Nine inbred lines of diverse genetic backgrounds were tested under adequate water supply and limited
water conditions. The genotypes showed substantial variation in shoot dry matter, water use, stomatal conductance, leaf temperature,
transpiration efficiency, carbon isotope discrimination (Δ13C), relative water content (RWC) and osmotic potential, determined at pre-flowering vegetative stage. Moisture deficits decreased
water usage and consequently shoot dry matter production. RWC, osmotic potential, stomatal conductance and Δ13C were lower, whereas leaf temperature and transpiration efficiency were higher in stressed plants, probably due to restricted
transpirational cooling induced by stomatal closure. Furthermore, differences in stomatal conductance, leaf temperature, Δ13C and transpiration efficiency characterized genotypes that were physiologically more adapted to water deficit conditions.
Correlation analysis also showed relatively strong relationships among these variables under well watered conditions. The
drought tolerant genotypes, ILB-938/2 and Melodie showed lower stomatal conductance associated with warmer leaves, whereas
higher stomatal conductance and cooler leaves were observed in sensitive lines (332/2/91/015/1 and Aurora/1). The lower value
of Δ13C coupled with higher transpiration efficiency in ILB-938/2, relative to sensitive lines (Aurora/1 and Condor/3), is indeed
a desirable characteristic for water-limited environments. Finally, the results showed that stomatal conductance, leaf temperature
and Δ13C are promising physiological indicators for drought tolerance in faba bean. These variables could be measured in pot-grown
plants at adequate water supply and may serve as indirect selection criteria to pre-screen genotypes. 相似文献
732.
Telomere Position Effect (TPE) is governed by strong repression signals emitted by telomeres via the Sir2/3/4 Histone Deacetylase complex. These signals are then relayed by weak proto-silencers residing in the subtelomeric core X and Y' elements. Subtelomeres also contain Sub-Telomeric Anti-silencing Regions (STARs). In this study we have prepared telomeres built of different combinations of core X, Y' and STARs and have analyzed them in strains lacking Histone-Acetyltransferase genes as well as in cdc6-1 and Δrif1 strains. We show that core X and Y' dramatically reduce both positive and negative variations in TPE, that are caused by these mutations. We also show that the deletion of Histone-Acetyltransferase genes reduce the silencing activity of an ACS proto-silencer, but also reduce the anti-silencing activity of a STAR. We postulate that core X and Y' act as epigenetic cushioning cis-elements. 相似文献
733.
Muhammad Abdul Aziz Muhammad Adnan Amir Hasan Khan Atiq Ur Rehman Rahmatullah Jan Jafar Khan 《Journal of ethnobiology and ethnomedicine》2016,12(1):53
Background
Medicinal flora plays a vital role in treating various types of ailments in living beings. The present study was planned to investigate and document systematically the indigenous knowledge in a scientifically little explored area of Ladha sub-division, South Waziristan agency, Pakistan. Hence, this study would contribute positively to the field of ethnopharmacology.Methods
Prior to ethnomedicinal data collection, regular field visits were conducted during the month of May and June 2015 to locate the sites and respondents from where the traditional knowledge was to be recorded. Ethno-medicinal data was collected during the month July and August 2015 through rapid appraisal approach (RAA) based on direct interaction with the indigenous communities by making group discussions, corner meetings and semi-structured interviews. Data was evaluated statistically by using the index of Use value (UV) and Frequency of citations (FC).Results
A total of 82 medicinal plants belonging to 42 families were reported in the study. Leaves were the most frequently used plant parts. Highest use values were recorded for Peganum harmala (0.93), Punica granatum (0.91), Thymus mongolicus (0.90), Chenopodium album (0.89), Coriandrum sativum (0.87), Mentha longifolia (0.87), Lactuca serriola (0.87) and Portulaca oleracea (0.87). Medicinal plants used for the gastro intestinal complexities and respiratory diseases were more than 9% followed by skin and diarrhea (7% each), liver disorders (5%) cough and cold fever (5%).Conclusion
People of the area mostly still rely on traditional herbal therapies. Keeping in mind the dependence of the indigenous community for their primary health care on such herbal remedies, pharmacological and critical toxicological investigation of certain flora is necessary. Moreover, projects should be designed to analyze the existing issues and problems related with medicinal plants conservation.734.
Hafiz Mamoon Rehman James William Cooper Hon‐Ming Lam Seung Hwan Yang 《Plant, cell & environment》2019,42(1):52-70
Legumes are the world's primary source of dietary protein and are particularly important for those in developing economies. However, the biofortification potential of legumes remains underexploited. Legumes offer a diversity of micronutrients and amino acids, exceeding or complementing the profiles of cereals. As such, the enhancement of legume nutritional composition presents an appealing target for addressing the “hidden hunger” of global micronutrient malnutrition. Affecting ~2 billion people, micronutrient malnutrition causes severe health effects ranging from stunted growth to reduced lifespan. An increased availability of micronutrient‐enriched legumes, particularly to those in socio‐economically deprived areas, would serve the dual functions of ameliorating hidden hunger and increasing the positive health effects associated with legumes. Here, we give an updated overview of breeding approaches for the nutritional improvement of legumes, and crucially, we highlight the importance of considering nutritional improvement in a wider ecological context. Specifically, we review the potential of the legume microbiome for agronomic trait improvement and highlight the need for increased genetic, biochemical, and environmental data resources. Finally, we state that such resources should be complemented by an international and multidisciplinary initiative that will drive crop improvement and, most importantly, ensure that research outcomes benefit those who need them most. 相似文献
735.
Rehman Shamsur Shahzad Babar Bajwa Ali Ahsan Hussain Saddam Rehman Abdul Cheema Sardar Alam Abbas Tasawer Ali Asif Shah Liaqat Adkins Steve Li Peijin 《Journal of Plant Growth Regulation》2019,38(1):343-356
Journal of Plant Growth Regulation - Sustainable crop production under changing climate is crucial to feed the increasing population of the world. Efforts are underway to discover novel strategies... 相似文献
736.
The rapid spread of SARS-CoV-2 has significantly impacted the worldwide health system. The SARS-CoV-2 currently bears a remarkably low genetic diversity even though it carries one of the largest RNA genomes among viruses (Rausch et al., 2020). However, the coronaviruses harbor the capability of undergoing recombination at a high rate which can lead to the emergence of novel viral derivatives (Rausch et al., 2020; Gribble et al., 2021). This in turn requires not only global surveillance of SARS-CoV-2 genome in various countries but also careful scrutiny in animal genomic reservoirs. Conventionally, RNA viruses evolve with a high mutation rate, however, the presence of ExoN ribonuclease in SARS-CoV-2 genome has made its case different from other viral species (Gribble et al., 2021). The variables of natural selection which potentially drift the SARS-CoV-2 evolutionary dynamics can be recorded by analyzing deposited sequence genomes for its fitness, transmissibility potential, and pathogenicity (Rouchka et al., 2020). This can potentially provide a way to draw a holistic picture at a national level, while simultaneously providing a comparative overview with worldwide sequences. 相似文献
737.
Hassan Waqas Yasir Gul Khan Rab Nawaz Muhammad Rizwan Muhammad Saif-Ur- Rehman 《人类与生态风险评估》2017,23(4):836-850
The present study was conducted to estimate As concentration in groundwater and resulting human health risk in terms of chronic daily intake, hazard quotient (HQ), hazard index (HI), and carcinogenic risk (CR) both for oral and dermal exposure to As. Groundwater samples (n = 100) were collected from ten different towns of Lahore District (Pakistan). Arsenic concentration ranged from 2 to 111 µg L?1 in groundwater samples of the study area, which was significantly greater than the safe limit of As (10 µg L?1) in drinking water set by the World Health Organization. Health risk assessment of As showed that HQ (0.1–11) for oral exposure and HI (0.1–11) values also exceeded the typical toxic risk index value of 1. 9.75 × E-05–4.59 × E-03 and 5.89 × E-07–2.77 × E-05 for oral and dermal As exposure, respectively. Both CR and cancer index (CIs) values were higher than United States Environmental Protection Agency limit (10?6), suggesting that people are at high risk of As-induced carcinogenicity from oral and dermal exposure to As in drinking water. It was concluded that As contamination of groundwater causes carcinogenic and noncarcinogenic health effects to the people; therefore, urgent management and remedial actions are required to protect people from As poisoning. 相似文献
738.
Combining 3D human in vitro methods for a 3Rs evaluation of novel titanium surfaces in orthopaedic applications 下载免费PDF全文
G. Stevenson S. Rehman E. Draper E. Hernández‐Nava J. Hunt J.W. Haycock 《Biotechnology and bioengineering》2016,113(7):1586-1599
In this study, we report on a group of complementary human osteoblast in vitro test methods for the preclinical evaluation of 3D porous titanium surfaces. The surfaces were prepared by additive manufacturing (electron beam melting [EBM]) and plasma spraying, allowing the creation of complex lattice surface geometries. Physical properties of the surfaces were characterized by SEM and profilometry and 3D in vitro cell culture using human osteoblasts. Primary human osteoblast cells were found to elicit greater differences between titanium sample surfaces than an MG63 osteoblast‐like cell line, particularly in terms of cell survival. Surface morphology was associated with higher osteoblast metabolic activity and mineralization on rougher titanium plasma spray coated surfaces than smoother surfaces. Differences in osteoblast survival and metabolic activity on titanium lattice structures were also found, despite analogous surface morphology at the cellular level. 3D confocal microscopy identified osteoblast organization within complex titanium surface geometries, adhesion, spreading, and alignment to the biomaterial strut geometries. Mineralized nodule formation throughout the lattice structures was also observed, and indicative of early markers of bone in‐growth on such materials. Testing methods such as those presented are not traditionally considered by medical device manufacturers, but we suggest have value as an increasingly vital tool in efficiently translating pre‐clinical studies, especially in balance with current regulatory practice, commercial demands, the 3Rs, and the relative merits of in vitro and in vivo studies. Biotechnol. Bioeng. 2016;113: 1586–1599. © 2015 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc. 相似文献
739.
Exposure of soil microbial communities to chromium and arsenic alters their diversity and structure 总被引:5,自引:0,他引:5
CS Sheik TW Mitchell FZ Rizvi Y Rehman M Faisal S Hasnain MJ McInerney LR Krumholz 《PloS one》2012,7(6):e40059
Extensive use of chromium (Cr) and arsenic (As) based preservatives from the leather tanning industry in Pakistan has had a deleterious effect on the soils surrounding production facilities. Bacteria have been shown to be an active component in the geochemical cycling of both Cr and As, but it is unknown how these compounds affect microbial community composition or the prevalence and form of metal resistance. Therefore, we sought to understand the effects that long-term exposure to As and Cr had on the diversity and structure of soil microbial communities. Soils from three spatially isolated tanning facilities in the Punjab province of Pakistan were analyzed. The structure, diversity and abundance of microbial 16S rRNA genes were highly influenced by the concentration and presence of hexavalent chromium (Cr (VI)) and arsenic. When compared to control soils, contaminated soils were dominated by Proteobacteria while Actinobacteria and Acidobacteria (which are generally abundant in pristine soils) were minor components of the bacterial community. Shifts in community composition were significant and revealed that Cr (VI)-containing soils were more similar to each other than to As contaminated soils lacking Cr (VI). Diversity of the arsenic resistance genes, arsB and ACR3 were also determined. Results showed that ACR3 becomes less diverse as arsenic concentrations increase with a single OTU dominating at the highest concentration. Chronic exposure to either Cr or As not only alters the composition of the soil bacterial community in general, but affects the arsenic resistant individuals in different ways. 相似文献
740.
Effect of dichromate on population and growth of various protozoa isolated from industrial effluents
Three protozoa belonging to genera Euglena, Vorticella and Stylonychia collected from industrial wastes were cultured in a medium containing inorganic salts, basically meant for the growth of algae. Protozoa showed rapid growth in the medium. Hexavalent chromium (K2Cr2O7) at a concentration of 5 micrograms/L in the medium adversely affected the growth of protozoa. At the end of eight days of Cr administration, the population of Euglena, Vorticella and Stylonychia increased 8-, 4.5- and 10-fold, respectively, as against 30-, 6.75- and 50-fold increase in the control cultures. No apparent death phase and no change in activity or morphology of protozoa was observed at this Cr concentration. The protozoa were also exposed to different metal ions, viz. Pb (2.42 mmol/L), Cr (0.48 mmol/L), Cd (0.36 mmol/L), administered in the culture medium for a period of 2 years. The metal tolerance for S. mytilus and V. microstoma was Pb > Cr > Cd. E. proxima could not tolerate any of the long-term metal treatments. Because of the ability of these protozoa to tolerate high concentrations of heavy metals, their potential role in remediation of heavy metals from industrial wastewater is considered. 相似文献