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21.
Munir Ahmad Adel Ghoneim Saud S. Al-Oud Khaled D. Alotaibi Mahmoud Nadeem 《Soil Science and Plant Nutrition》2019,65(2):183-195
Phosphate rock (PR) was activated via acidulation with HCl, EDTA, and oxalic acid to enhance its reactivity. The release, lateral transport, and uptake of phosphorus (P) along with trace metals from pristine and activated PRs were investigated in a soil micro-block system over a period of 27 days, using wheat (Triticum aestivum L.) plants. Significantly (p < 0.05) higher amounts of available soil P, Fe, Mn, and Zn were released from all the PRs after application to soil within first 9 days of seedling transplantation, while the release of other trace metals (Cd, Co, Cr, Cu, Ni, and Pb) was minimal (<1.2 mg kg?1). On cumulative basis, APR-O (oxalic acid activated PR) was the most efficient amendment releasing 164% more available P, followed by APR-E (EDTA activated PR) releasing 130% more available P, compared to the pristine PR. Similar results were also observed in the release of available Fe, Mn, Zn, and other trace metals. The highest diffusive mass fluxes for available P, Mn, Fe, and Zn in soil were observed after 3 days of seedling transplantation, which reduced subsequently. The uptake of P, Fe, Mn, and Zn by wheat plants was increased by 394%, 715%, 92%, and 91%, respectively, in APR-O application compared to the pristine PR, while it was increased by 280%, 188%, 16%, and 27%, respectively, in APR-E application compared to the pristine PR. Subsequently, APR-O and APR-E amendments resulted in enhanced shoot lengths, root lengths, shoot dry matter, and root dry matter contents of wheat plants. Hence, it was concluded that activation of PR with oxalic acid and EDTA prior to direct soil application may enhance the reactivity of PR and could serve as a cost-effect fertilization strategy for higher wheat crop production. 相似文献
22.
Shankar Reddy Kolle T. H. Shankarappa Basir Ahmad Rahimi M. V. Satish 《Journal Of Agricultural & Food Information》2019,20(1):25-38
A review of publications on “Strawberry” was done by using the Scopus database for the period 1960–2016. A total of 10,400 articles were found in the database and analyzed using a variety of measures. Results show that publication increased exponentially from 1960 to 2016. Multiple authors are collaborating in strawberry research. Acta Horticulturae was the most productive journal. The United States of America was the most productive country. The greatest portion of the research was concerned with medicinal benefits of strawberries to humans. This work will be useful to researchers in identifying trends in strawberry research. 相似文献
23.
Irshad Ahmad Bashir Ahmad Shahzad Ali Muhammad Kamran Bayasgalan Bilegjargal 《Journal of plant nutrition》2017,40(15):2109-2115
The objective of this study was to evaluate the effects of organic and inorganic fertilizers on the yield and quality of sugar beet genotypes (Beta vulgaris L.). Therefore, a field trial was carried out in Peshawar, Pakistan, during the winters in 2012–2013. The field experiment was conducted in a randomized complete block design with split plots, having three replications. Fertilizer treatments (control, composted manure Higo Organic Plus at 5 t ha?1, Maxicrop Sea Gold seaweed extract at 5 L ha?1, farm yard manure at 10 t ha?1, inorganic nitrogen–phosphorus (NP) at 90:60 kg ha?1, NP at 120:90 kg ha?1 and NP at 150:120 kg ha?1) were allotted to main plots, while genotypes (Sandrina, Serenada and Kawe Terma) were allotted to the sub-plots. Plots treated with the application of NP at 120:90 kg ha?1 produced the highest beet yield (76.4 t ha?1) and sugar yield (11.1 t ha?1), and had the second highest polarizable sugar content (14.52%) and more economic return (Rs. 553,000 per hectare) as compared to control plots. Sugar beet genotype Serenada had significantly higher beet yield (55.5 t ha?1) and sugar yield (7.9 t ha?1) and a higher economic return (Rs. 380,000 per hectare) than the other genotypes. Sugar beet genotype Serenada supplied with NP at 120:90 kg ha?1is recommended for the general cultivation in the agro-climatic conditions of Peshawar valley. 相似文献
24.
Mahtab Ahmad Sang Soo Lee Sung Eun Lee Mohammad I. Al-Wabel Daniel C. W. Tsang Yong Sik Ok 《Journal of Soils and Sediments》2017,17(3):717-730
Purpose
Remediation of metal contaminated soil with biochar is attracting extensive interest in recent years. Understanding the significance of variable biochar properties and soil types helps elucidating the meticulous roles of biochar in immobilizing/mobilizing metals/metalloids in contaminated soils.Materials and methods
Six biochars were produced from widely available agricultural wastes (i.e., soybean stover, peanut shells and pine needles) at two pyrolysis temperatures of 300 and 700 °C, respectively. The Pb-, Cu-, and Sb-contaminated shooting range soils and Pb-, Zn-, and As-contaminated agricultural soils were amended with the produced biochars. The mobility of metals/metalloids was assessed by the standard batch leaching test, principal component analysis and speciation modeling.Results and discussion
The changes in soil properties were correlated to feedstock types and pyrolysis temperatures of biochars based on the principal component analysis. Biochars produced at 300 °C were more efficient in decreasing Pb and Cu mobility (>93 %) in alkaline shooting range soil via surface complexation with carboxyl groups and Fe-/Al-minerals of biochars as well as metal-phosphates precipitation. By contrast, biochars produced at 700 °C outperformed their counterparts in decreasing Pb and Zn mobility (100 %) in acidic agricultural soil by metal-hydroxides precipitation due to biochar-induced pH increase. However, Sb and As mobility in both soils was unfavorably increased by biochar amendment, possibly due to the enhanced electrostatic repulsion and competition with phosphate.Conclusions
It is noteworthy that the application of biochars is not equally effective in immobilizing metals or mobilizing metalloids in different soils. We should apply biochar to multi-metal contaminated soil with great caution and tailor biochar production for achieving desired outcome and avoiding adverse impact on soil ecosystem.25.
Dynamic oxygen mapping in the root zone by fluorescence dye imaging combined with neutron radiography 总被引:1,自引:0,他引:1
Nicole Rudolph Hanna G. Esser Andrea Carminati Ahmad B. Moradi André Hilger Nikolay Kardjilov Stefan Nagl Sascha E. Oswald 《Journal of Soils and Sediments》2012,12(1):63-74
Purpose
The rooted zone of a soil, more precisely the rhizosphere, is a very dynamic system. Some of the key processes are water uptake and root respiration. We have developed a novel method for measuring the real-time distribution of water and oxygen concentration in the rhizosphere as a biogeochemical interface in soil. This enables understanding where and when roots are active in respect to root respiration and water uptake and how the soil responds to it. 相似文献26.
The concentration and size distribution of bacterial and fungal aerosol was studied in 15 houses. The houses were categorized into three types, based on occupant density and number of rooms: single room in shared accommodation (type I), single bedroom flat in three storey buildings (type II) and two or three bedroomed houses (type III). Sampling was undertaken with an Anderson six-stage impactor during the summer of 2007 in the living rooms of all the residential settings. The maximum mean geometric concentration of bacterial (5,036 CFU/m3, ± 2.5, n?=?5) and fungal (2,124 CFU/m3, ± 1.38, n?=?5) aerosol were in housing type III. The minimum levels of indoor culturable bacteria (1,557 CFU/m3, ±1.5, n?=?5) and fungal (925 CFU/m3, ±2.9, n?=?5) spores were observed in housing type I. The differences in terms of total bacterial and fungal concentration were less obvious between housing types I and II as compared to type III. With reference to size distribution, the dominant stages for culturable bacteria in housing types I, II and III were stage 3 (3.3–4.7 μm), stage 1 (7 μm and above) and stage 5 (1.1–2.1 μm), respectively. Whereas the maximum numbers of culturable fungal spores were recovered from stage 2 (4.7–7 µm), in housing type I, and from stage 4 (2.1–3.3 μm) in both type II and III houses. The average geometric mean diameter of bacterial aerosol was largest in type I (4.7 μm), followed by type II (3.89 μm) and III (1.96 μm). Similarly, for fungal spores, type I houses had the highest average mean geometric diameter (4.5 μm), while in types II and III the mean geometric diameter was 3.57 and 3.92 μm, respectively. The results indicate a wide variation in total concentration and size of bioaerosols among different residential settings. The observed differences in the size distributions and concentrations reflect their variable airborne behaviour and, as a result, different risks of respiratory exposure of the occupants to bioaerosols in various residential settings. 相似文献
27.
In cereals, chromosome doubling of microspore-derived haploid plants is a critical step in producing doubled haploid plants.
This investigation was undertaken to study the effect of incorporation of colchicine in the induction medium for anther culture,
and the effect of colchicine on anther culture-derived plants of triticale grown under controlled greenhouse conditions. In
the latter case, chromosome doubling of adult sterile plants derived from anther culture of fourteen triticale populations
was attempted, where androgenetic plants with non-dehiscent anthers were cloned and subjected to the colchicine treatment,
and then grown with the aid of hydroponics. The hydroponic system provided optimal conditions for recovery of the affected
haploids from the toxic effects of colchicine treatment and all colchicine-treated plants survived. A topcross-F1 (TC1F1) population with timopheevii cytoplasm produced the highest percentage of plants with seed-set either due to chromosome doubling
by colchicine (98%) or spontaneous doubling of chromosome number (15%). Colchicine-treated anthers performed inferior than
control in both induction and regeneration phases. One of the key observation of this study was the reversal from reproductive
stage back to the vegetative stage which in turn enabled further cloning of haploid plants under hydroponic conditions once
they were identified as sterile. The one hundred percent survival rate of in vitro-derived plants, 100% survival rate of colchicine treated haploid plants and the high chromosome doubling success rate (X
= 82.3) observed in this study imply that a temperature-controlled greenhouse with an hydroponic system provides an efficient
environment for inducing chromosome doubling of haploid plants in cereals.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
28.
Energy and water balance measurements for water productivity analysis in irrigated mango trees, Northeast Brazil 总被引:2,自引:0,他引:2
A.H. de C. Teixeira W.G.M. Bastiaanssen M.S.B. Moura J.M. Soares M.D. Ahmad M.G. Bos 《Agricultural and Forest Meteorology》2008,148(10):1524-1537
Crop water parameters, including actual evapotranspiration, transpiration, soil evaporation, crop coefficients, evaporative fractions, aerodynamic resistances, surface resistances and percolation fluxes were estimated in a commercial mango orchard during two growing seasons in Northeast Brazil. The actual evapotranspiration (Ea) was obtained by the eddy covariance (EC) technique, while for the reference evapotranspiration (E0); the FAO Penman–Monteith equation was applied. The energy balance closure showed a gap of 12%. For water productivity analysis the Ea was then computed with the Bowen ratio determined from the eddy covariance fluxes. The mean accumulated Ea for the two seasons was 1419 mm year−1, which corresponded to a daily average rate of 3.7 mm day−1. The mean values of the crop coefficients based on evapotranspiration (Kc) and based on transpiration (Kcb) were 0.91 and 0.73, respectively. The single layer Kc was fitted with a degree days function. Twenty percent of evapotranspiration originated from direct soil evaporation. The evaporative fraction was 0.83 on average. The average relative water supply was 1.1, revealing that, in general, irrigation water supply was in good harmony with the crop water requirements. The resulting evapotranspiration deficit was 73–95 mm per season only. The mean aerodynamic resistance (ra) was 37 s m−1 and the bulk surface resistance (rs) was 135 s m−1. The mean unit yield was 45 tonne ha−1 being equivalent to a crop water productivity of 3.2 kg m−3 when based on Ea with an economic counterpart of US$ 3.27 m−3. The drawback of this highly productive use of water resources is an unavoidable percolation flux of approximately 300 mm per growing season that is detrimental to the downstream environment and water users. 相似文献
29.
Fahd M. Abdelkarem Mohamed E. Abouelela Mohamed R. Kamel Alaa M. Nafady Ahmed E. Allam Iman A. M. Abdel-Rahman Ahmad Almatroudi Faris Alrumaihi Khaled S. Allemailem Hamdy K. Assaf 《Marine drugs》2022,20(2)
Gorgostane steroids are isolated from marine organisms and consist of 30 carbon atoms with a characteristic cyclopropane moiety. From the pioneering results to the end of 2021, isolation, biosynthesis, and structural elucidation using 13C-NMR will be used. Overall, 75 compounds are categorized into five major groups: gorgost-5-ene, 5,6-epoxygorgostane, 5,6-dihydroxygorgostane, 9,11-secogorgostane, and 23-demethylgorgostane, in addition to miscellaneous gorgostane. The structural diversity, selectivity for marine organisms, and biological effects of gorgostane steroids have generated considerable interest in the field of drug discovery research. 相似文献
30.
为探明药隔期低温胁迫对小麦产量的影响,以烟农19、新麦26为供试材料,在小麦药隔期进行不同程度(T1:2℃/4h、T2:0℃/4h、T3:-2℃/4h)的低温处理,研究药隔期低温胁迫对小麦干物质积累、转运和分配及产量的影响.结果 表明:药隔期低温胁迫显著降低小麦干物质积累量,不同抗倒春寒性小麦品种间干物质积累量存在差异,抗倒春寒性弱的小麦品种降幅更大.其中烟农19的T1、T2、T3处理分别降低33.4%、46.2%和54.7%,而新麦26则分别降低了50.1%、59.3%和72.4%.不同处理小麦籽粒、穗轴+颖壳、茎鞘+叶的干物质积累量均低于CK,且随着低温胁迫程度的加重呈明显降低趋势.小麦花前干物质的转运量、转运效率以及花前贮藏干物质对籽粒的贡献率均随着低温胁迫程度加重呈降低趋势.同时低温胁迫显著降低小麦籽粒和穗轴+颖壳的干物质分配比例,增加茎鞘+叶的分配比例.T1、T2和T3处理显著降低了小麦的穗粒数和千粒重及籽粒产量,烟农19的T1、T2和T3处理分别减产56.06%、86.36%和98.10%;新麦26的T1、T2和T3处理分别减产96.15%、98.07%和98.46%.药隔期低温胁迫显著降低小麦干物质的积累量、花前干物质的转运量、转运效率以及花前贮藏干物质对籽粒的贡献率和籽粒干物质分配比例,严重减少光合同化物向穗部的转运和分配,影响穗部小花的正常发育,从而导致穗粒数的减少,这是造成小麦减产的主要原因. 相似文献