1,720,975 research outputs found
Composted Sugarcane By‐product Press Mud Cake Supports Wheat Growth and Improves Soil Properties
No full textRestoring soil fertility is essential to sustain crop production in order to meet the needs of the ever-blooming population. In this light, the present investigation was carried on the same soil for two consecutive years (2014-15 and 2015-16) in Punjab, Pakistan, to determine the influence of press mud compost (PMC) and mineral fertilizers (NPK) on wheat growth, yield and soil properties. The experiment was composed of an unfertilized control and five inter-exchanging combinations of NPK and PMC (100:0, 75:25, 50:50, 25:75, 0:100). 100% PMC (900 kg ha-1) was intermediate in wheat growth and yield between unfertilized and 100% NPK, this latter being the recommended dose of mineral nutrients (120, 100 and 60 kg ha-1 of the respective N, P2O5, and K2O). The 50:50 combinations of NPK and PMC determined the best growth and final yield (+19% vs. 100% NPK), despite an approximately 40% lower nutrient supply with respect to 100% NPK. Soils traits bulk density, pH, organic matter, total N, and available nutrients P and K significantly improved with 100% PMC. Based on the ANOVA, the 50:50 combinations of NPK and PMC was no worse than 100% PMC in bulk density, available P and K, and it was a good compromise between 100% NPK and 100% PMC in organic matter content. Therefore, conjunctive use of PMC and NPK fertilizers appeared a good choice to improve wheat productivity and soil properties. Additionally, the use of PMC will lower the reliance on mineral fertilizers while restoring soil fertility and assuring environmental protection
Combined cultivar and harvest time to enhance biomass and methane yield in sorghum under warm dry conditions in Pakistan
No full textMethane from agricultural biomass contributes to achieving self-reliance and sustainability in alternative energy sources. In this framework, a two-year experiment was set up in Punjab, Pakistan, combining four cultivars (CV) of biomass sorghum with five harvest times (HT) (from 60 to 120 days after sowing) (DAS). HT and CV, both alone and together strongly influenced morphological, compositional and yield traits. Dual purpose (grain and biomass) CV (Jawar-2011 and JS-263) attained higher dry biomass yield (DBY) than fibre CV (Hagari and JS-2002) (+22%), possibly due to a stronger sink for assimilates at late growth stages. Delayed harvest (120 vs. 60 DAS) determined the largest differences in all traits: increase in DBY (+48% DBY), hemi-cellulose (+80%),
cellulose (+85%) and lignin (+41%), and concurrent decrease in protein (−22%) and ash (−28%). These compositional changes indicate a strengthening in plant structure with advancing maturity that negatively reflected on specific methane yield (SMY) (−17%). However, average SMY obtained with sorghum in the warm dry conditions of Pakistan (290 lN kg−1 VS) is consistent with data observed at higher latitudes under temperate climate. The significant HT×CV interactions for DBY, SMY and their product, methane yield per hectare, were fitted by means of functions describing CV trends in time. Based on this, suitable combinations of HT and CV can be envisaged to balance methane yield and bio-degradability over a reasonable harvest window. On concluding, data obtained in this experiment disclose favourable prospects for sorghum as bio-methane feedstock in warm dry areas of the world
Neem and Castor Oil–Coated Urea Mitigates Salinity Effects in Wheat by Improving Physiological Responses and Plant Homeostasis
Full text linkSoil salinity is abiotic stress of growing concern, whose effects can be potentially mitigated by the use of suitable fertilisers. Based on this, an experiment was conducted to determine the role of vegetable oil–coated urea on the performance of wheat (Triticum aestivum) under salinity. Neem oil–coated urea (NOCU), castor oil–coated urea (COCU), and normal urea (NU) were compared in wheat plants growing in pots at three soil salinity levels (0, 6, and 12 dS m-1). Plant morphology, growth, element contents (Na, Cl, K, and N), and several traits were assessed at the flag leaf stage; biological yield, grain yield, and its components were assessed at maturity. Salinity stunted growth (approximately -50% yield with high salinity vs. control); boosted Na and Cl concentrations while abating K and N concentrations in plant organs; impaired leaf water status; reduced photosynthetic pigments and increased antioxidant activities and osmo-regulating compounds. NOCU and, to a lesser degree, COCU mitigated salinity effects by upgrading antioxidant activities, reducing oxidative stress markers, increasing leaf water status, photosynthetic pigments, and osmo-regulating compounds. However, NOCU under high salinity could only achieve the levels of NU under intermediate salinity. Lastly, NOCU and COCU restricted plant entry of adverse ions (Na and Cl) while increasing K and N accumulation. Vegetable oil–coated urea, namely NOCU, significantly contributed to improving wheat behaviour and final yield under salinity. These outcomes are associated with the two fertilisers’ properties of slow nitrogen release
Melatonin Induced Cold Tolerance in Plants: Physiological and Molecular Responses
Full text linkCold stress is one of the most limiting factors for plant growth and development. Cold stress adversely affects plant physiology, molecular and biochemical processes
by determining oxidative stress, poor nutrient and water uptake, disorganization of cellular membranes and reduced photosynthetic efficiency. Therefore, to recover impaired plant functions under cold stress, the application of bio-stimulants can be
considered a suitable approach. Melatonin (MT) is a critical bio-stimulant that has
often shown to enhance plant performance under cold stress. Melatonin application
improved plant growth and tolerance to cold stress by maintaining membrane integrity, plant water content, stomatal opening, photosynthetic efficiency, nutrient and water uptake, redox homeostasis, accumulation of osmolytes, hormones and secondary metabolites, and the scavenging of reactive oxygen species (ROS) through improved antioxidant activities and increase in expression of stress-responsive genes. Thus, it is essential to understand the mechanisms of MT induced cold tolerance and identify the diverse research gaps necessitating to be addressed in future research programs. This review discusses MT involvement in the control of various physiological and molecular responses for inducing cold tolerance. We also shed light on engineering MT biosynthesis for improving the cold tolerance in plants. Moreover, we highlighted areas where future research is needed to make MT a vital antioxidant conferring cold tolerance to plants
Mulberry based zinc nano-particles mitigate salinity induced toxic effects and improve the grain yield and zinc bio-fortification of wheat by improving antioxidant activities, photosynthetic performance, and accumulation of osmolytes and hormones
Full text linkSalinity stress (SS) is a challenging abiotic stress that limits crop growth and productivity. Sustainable and cost effective methods are needed to improve crop production and decrease the deleterious impacts of SS. Zinc (Zn) nano-particles (NPs) have emerged as an important approach to regulating plant tolerance against SS. However, the mechanisms of SS tolerance mediated by Zn-NPs are not fully explained. Thus, this study was performed to explore the role of Zn-NPs (seed priming and foliar spray) in reducing the deleterious impacts of SS on wheat plants. The study comprised different SS levels: control, 6 and 12 dS m(−1), and different Zn-NPs treatments: control, seed priming (40 ppm), foliar spray (20 ppm), and their combination. Salinity stress markedly reduced plant growth, biomass, and grain yield. This was associated with enhanced electrolyte leakage (EL), malondialdehyde (MDA), hydrogen peroxide (H(2)O(2)), sodium (Na), chloride (Cl) accumulation, reduced photosynthetic pigments, relative water contents (RWC), photosynthetic rate (Pn), transpiration rate (Tr), stomata conductance (Gs), water use efficiency (WUE), free amino acids (FAA), total soluble protein (TSP), indole acetic acid (IAA), gibberellic acid (GA), and nutrients (Ca, Mg, K, N, and P). However, the application of Zn-NPs significantly improved the yield of the wheat crop, which was associated with reduced abscisic acid (ABA), MDA, H(2)O(2) concentration, and EL, owing to improved antioxidant activities, and an increase in RWC, Pn, Tr, WUE, and the accumulation of osmoregulating compounds (proline, soluble sugars, TSP, and FAA) and hormones (GA and IAA). Furthermore, Zn-NPs contrasted the salinity-induced uptake of toxic ions (Na and Cl) and increased the uptake of Ca, K, Mg, N, and P. Additionally, Zn-NPs application substantially increased the wheat grain Zn bio-fortification. Our results support previous findings on the role of Zn-NPs in wheat growth, yield, and grain Zn bio-fortification, demonstrating that beneficial effects are obtained under normal as well as adverse conditions, thanks to improved physiological activity and the accumulation of useful compounds. This sets the premise for general use of Zn-NPs in wheat, to which aim more experimental evidence is intensively being sought. Further studies are needed at the genomic, transcriptomic, proteomic, and metabolomic level to better acknowledge the mechanisms of general physiological enhancement observed with Zn-NPs application
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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