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501.
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
502.
Ebtehal El‐Sayed Hussein Konrad Dabrowski Deyab M S D El‐Saidy Bong‐Joo Lee 《Aquaculture Research》2013,44(6):937-949
Diets incorporating different levels of corn gluten meal replacement using biofuel algae or Spirulina protein at 0%, 25%, 50%, 75% and 100% were evaluated for larval/juvenile stage of Nile tilapia (Oreochromis niloticus). Fish averaging 0.02 g were divided into groups of 50. There were three replicates per every dietary treatment that were fed one of six diets for 11 weeks. Corn gluten protein was replaced with algae on the protein basis. All diets were supplemented with 1.5% lysine and 0.5% methionine. The experimental diets were formulated to contain 37 ± 2.8% protein and 14 ± 4.3% lipid in the form of fish oil and soybean lecithin (phospholipids source). The results indicated that algae positively affected feed consumption and fish growth up to the 50% replacement and then performance was depressed. Significant differences in concentration of individual minerals (Al, Fe, Zn and Cu) in the whole fish body were found. Mineral composition of algae might have affected growth when diets which contained more than 75% of plant protein were replaced with microalgae. These findings suggest that up to 50% of dietary corn gluten meal protein can be replaced with microalgae which significantly enhance fish growth. 相似文献
503.
David N. Laband Anwar Hussain Armando Gonzlez-Cabn 《Forest Policy and Economics》2008,10(7-8):444-449
In this paper, we explore empirically whether the USDA Forest Service's litigation success rate in each Forest Service region helps explain the persistent regional effects noted by Laband et al. (Laband, D.N., González-Cabán, A., and Hussain, A. (2006). “Factors That Influence Administrative Appeals of Proposed USDA Forest Service Fuels Reduction Actions,” Forest Science, 52(5): 477–488.) with respect to the pattern of administrative appeals of proposed fuels reduction actions. We find strong evidence of an inverse relationship between the Forest Service's litigation success rate and the likelihood of administrative appeal of proposed fuels reduction actions on public lands. However, inclusion of this variable explains only about 20% of the region-specific impact noted in Laband et al. (Laband, D.N., González-Cabán, A., and Hussain, A. (2006). “Factors That Influence Administrative Appeals of Proposed USDA Forest Service Fuels Reduction Actions,” Forest Science, 52(5): 477–488.), which continues to command additional investigation. 相似文献
504.
Structural root growth of young Veronese poplars on erodible slopes in the southern North Island,New Zealand 总被引:1,自引:0,他引:1
I. R. McIvor G. B. Douglas S. E. Hurst Z. Hussain A. G. Foote 《Agroforestry Systems》2008,72(1):75-86
In New Zealand poplars are commonly planted on moist, unstable pastoral hill country to prevent or reduce soil erosion, thereby
maintaining hillslope integrity and pasture production. Mechanical reinforcement by poplar root systems aids slope stabilisation.
Root mass and distribution were determined for three Populus deltoides × nigra ‘Veronese’ trees aged 5, 7 and 9.5 year planted as 3 m poles at 8 m × 8 m spacing on a hillslope near Palmerston North in
the southern North Island. Most of the structural roots (≥2 mm diameter) were distributed in the top 40 cm of soil. Vertical
roots penetrated to about 1.0 m, being the depth of the soil above a fragipan. Total structural root dry masses (excluding
root crown) were 0.57, 7.8 and 17.90 kg for the trees aged 5, 7 and 9.5 year, respectively. Total structural root length was
79.4 m for the 5 year tree and 663.5 m for the 9.5 year tree. Surrounding trees were estimated to increase root mass density
to 3 times and root length density to 4–5 times the contribution of the single tree at 9.5 year. The study indicated that
root development of wide-spaced poplar trees on hillslopes was minimal in the first 5 years but then increased rapidly. These
results suggest that poplar trees established from poles may take at least 5 years to develop a structural root network that
will effectively bind soil. 相似文献
505.
Sulaiman MR Hussain MK Zakaria ZA Somchit MN Moin S Mohamad AS Israf DA 《Fitoterapia》2008,79(7-8):557-561
The aqueous extract of Ficus deltoidea leaves was evaluated for possible antinociceptive activity in three models of nociception, namely, acetic acid-induced abdominal writhing, formalin and hot plate test. The results of the present study showed that intraperitoneal administration of the F. deltoidea leaves aqueous extract at the dose of 1, 50 and 100 mg/kg, 30 min prior to pain induction produced significant dose-dependent antinociceptive effect in all the models used, which indicating the presence of both central and peripherally mediated activities. Furthermore, the antinociceptive effect of the extract in the formalin and hot plate test was reversed by the non-selective opioid receptor antagonist naloxone suggesting that the endogenous opioid system is involved in its analgesic mechanism of action. Thus, the present results demonstrated that F. deltoidea leaves aqueous extract contains pharmacologically active constituents which possess antinociceptive activity justifying its popular therapeutic use in treating conditions associated with the painful conditions. 相似文献
506.
Aijaz Hussain Mir M.A. Khan Faculty of Forestry Sher-e-Kashmir University of Agricultural Sciences Technology of Kashmir Shalimar Srinagar- India 《林业研究》2008,(4)
2005.2006年间,在印度喀什米尔地区的克什米尔农业科学大学的试验地对农林兼作体系进行研究,柳树与农作物的间混种植包括柳树,羽衣甘蓝(Brassica oleracea Var.acephala)和球茎甘蓝(Brassica oleracea var.caularapa)。试验地分成几个小区,每个小区(8m×2m)种植4棵两年生的柳树,间距为2m×2m。采用被推荐的间混种植的植株间距和施用的肥料浓度。结果表明:羽衣甘蓝和球茎甘蓝与柳树间混种植得出这种的种植模式的预计效益成本率分别为2.78和2.79,单独的柳树种植效益率为2.66。本研究表明,可以促进蔬菜作物与柳树间混种植模式从而代替单独的柳树种植模式。图1表7参27。 相似文献
507.
508.
Muhammad Zia-Ul-Haq Abdul Khaliq Sheng QIANG Amar Matloob Saddam Hussain Saba Fatima Zeshan Aslam 《农业科学学报》2019,18(4):907-926
To ascertain the influence of wheat stubble management options and chemical weed control methods on weed growth and productivity of dry direct-seeded fine rice, a two years' field study was undertaken at the Agronomic Research Farm, University of Agriculture, Faisalabad, Pakistan in 2013 and 2014. Different wheat stubble management methods, viz., incorporation, burning and retention were executed during seed-bed preparation. While, herbicide treatments comprised of a weed check, weed free, pendimethalin followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl, and bispyribac sodium followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl. Results revealed that weed control efficacy of both herbicide treatments ranged from 84 to 94%. Herbicide treatments significantly reduced weed density(88–90%) and dry weight(86–88%), while improved the rice growth attributes compared with weed check. Application of bispyribac sodium followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl in stubble retention recorded 226 and 273% increase in kernel yield over weedy check in 2013 and 2014, respectively. In stubble incorporation, pendimethalin followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl was more effective in increasing(256–293%) rice yields over weedy check. Among different treatment combinations, the maximum net benefits(1 397.49~(–1) 472.22 USD ha~(–1)), net returns(636–700 USD ha~(–1)), benefit cost ratio(1.77~(–1).83) and marginal rate of return(2 187–2 330%) were recorded with the application of bispyribac sodium followed by fenoxaprop p-ethyl+ethoxysulfuron ethyl in stubble retention. In crux, application of bispyribac sodium followed by tank mixture of fenoxaprop p-ethyl+ethoxysulfuron ethyl in stubble retention is efficient approach to control weeds, and get maximum rice productivity and net economic returns under dry seeded system. 相似文献
509.
Barnett BP Hwang Y Taylor MS Kirchner H Pfluger PT Bernard V Lin YY Bowers EM Mukherjee C Song WJ Longo PA Leahy DJ Hussain MA Tschöp MH Boeke JD Cole PA 《Science (New York, N.Y.)》2010,330(6011):1689-1692
Ghrelin is a gastric peptide hormone that stimulates weight gain in vertebrates. The biological activities of ghrelin require octanoylation of the peptide on Ser(3), an unusual posttranslational modification that is catalyzed by the enzyme ghrelin O-acyltransferase (GOAT). Here, we describe the design, synthesis, and characterization of GO-CoA-Tat, a peptide-based bisubstrate analog that antagonizes GOAT. GO-CoA-Tat potently inhibits GOAT in vitro, in cultured cells, and in mice. Intraperitoneal administration of GO-CoA-Tat improves glucose tolerance and reduces weight gain in wild-type mice but not in ghrelin-deficient mice, supporting the concept that its beneficial metabolic effects are due specifically to GOAT inhibition. In addition to serving as a research tool for mapping ghrelin actions, GO-CoA-Tat may help pave the way for clinical targeting of GOAT in metabolic diseases. 相似文献
510.
Quazi T. H. Shubhra A. K. M. M. Alam M. A. Gafur Sayed M. Shamsuddin Mubarak A. Khan M. Saha Dipti Saha M. A. Quaiyyum Jahangir A. Khan Md. Ashaduzzaman 《Fibers and Polymers》2010,11(5):725-731
Natural fibers are largely divided into two categories depending on their origin: plant based and animal based. Plant based
natural jute fiber reinforced polypropylene (PP) matrix composites (20 wt% fiber) were fabricated by compression molding.
Bending strength (BS), bending modulus (BM), tensile strength (TS), Young’s modulus (YM), and impact strength (IS) of the
composites were found 44.2 MPa, 2200 MPa, 41.3 MPa, 750 MPa and 12 kJ/m2, respectively. Animal based natural B. mori silk fiber reinforced polypropylene (PP) matrix composites (20 wt% fiber) were fabricated in the same way and the mechanical
properties were compared over the silk based composites. TS, YM, BS, BM, IS of silk fiber reinforced polypropylene composites
were found 55.6 MPa, 760 MPa, 57.1 MPa, 3320 MPa and 17 kJ/m2 respectively. Degradation of composites in soil was measured upto twelve weeks. It was found that plant based jute fiber/PP
composite losses its strength more than animal based silk fiber/PP composite for the same period of time. The comparative
study makes it clear that mechanical properties of silk/PP composites are greater than those values of jute/PP composites.
But jute/PP composites are more degradable than silk/PP composites i.e., silk/PP composites retain their strength for a longer
period than jute/PP composites. 相似文献