Effect of salinity on nitrogen metabolism in wheat     

S.M. Abdul‐Kadir  G.M. Paulsen 《Journal of plant nutrition》2013,36(9):1141-1151

Objectives of our studies were to quantify effects of salinity on growth and nitrogen metabolism of wheat and to measure variation in response of different cultivars, hybrids, and classes. Methods and criteria for identifying resistance to salinity in wheat, particularly effects on nitrogen metabolism also were tested. Variation in response to salinity was measured by subjecting seedlings of six wheats to one control treatment (‐0.1 bars) and two stress treatments (‐3.5 and ‐10.4 bars) from NaCl, MgSO₄, and MgCl₂ in hydroponic solutions. Both stress treatments retarded growth; wheats significantly varied at ‐3.5 bars but not at ‐10.4 bars. Stress decreased root and shoot nitrate N and total N contents. Studies with one wheat cultivar showed that salinity decreased activity of nitrate reductase enzyme and stimulated accumulation of proline. Salinity more adversely affected vegetative stages than reproductive stages of plants grown to maturity. We concluded that salinity affected wheat by both osmotic effects and antagonism of nitrate metabolism from chloride. Absolute growth and relative growth at different stress levels were superior to differences in nitrogen metabolism as selection criteria for salinity tolerance.  相似文献   

A 3-Year Adaptation Study of Three Distinct Grapevine Cultivars under Midwestern Field Conditions     

Said Ennahli  Sorkel Kadir  Houchang Khatamian  David Scurlock  Hafida Hanine 《International Journal of Fruit Science》2017,17(1):1-19

Simultaneous responses of American (Concord), European (Pinot Noir), and American-European hybrid (Traminette) cultivars to seasonal and diurnal variation in field environmental conditions were assessed to propose suitable cultivars for potential use for selection and breeding in grapevines in dry areas. ‘Pinot Noir’ had higher gas exchange parameters, higher water potential, and chlorophyll fluorescence, while ‘Concord’ had the lowest values in all three seasons and experienced moderate stress by the end of each season. The dry conditions in 2005 caused water potential to decline sharply compared to values recorded in 2004 and 2006. ‘Pinot Noir’ and ‘Traminette’ exhibited a mild stress, while ‘Concord’ exhibited a moderate stress in 2006. Photosynthetic rate decreased slightly during the summer with a slight recovery at the beginning of September, and did not differ across the seasons among cultivars. Stomatal conductance followed the same pattern. However, in both 2004 and 2005, stomatal conductance dropped sharply late in the season because of frequently occurring high temperatures that were greater than 32 °C. Maximum morning values of Fv/Fm were within the optimal range. The study suggests the presence of marginal photoinhibition during mid-summer in Concord cultivars, because no full recovery of photochemical efficiency early in the evening was observed. The European cultivar (Pinot Noir) and the American-European hybrid (Traminette) are more adapted to field conditions in Kansas than Concord cultivars. However, high cold-mortality of Pinot Noir due to high sensitivity to cold winter temperature makes the hybrid cultivars the most suitable cultivar for Midwest regions with relatively cold winters.  相似文献   

Copolymerization of benzyl methacrylate and a methacrylate bearing benzophenoxy and hydroxyl side groups: Monomer reactivity ratios,thermal studies and dielectric measurements     

Fatih Biryan  Kadir Demirelli 《Fibers and Polymers》2017,18(9):1629-1637

Statistical copolymers of 2-hydroxy-3-benzophenoxy propyl methacrylate (HBPPMA) and benzyl methacrylate (BzMA) in different feed ratios were synthesized by free radical copolymerization method at 60 °C in presence of AIBN initiator. The compositions of copolymer were estimated from ¹H-NMR technique. The monomer reactivity ratios of HBPPMA and BzMA were calculated as r₁ (r_HBPPMA)=0.51±0.076 and r₂ (r_BzMA)=1.07±0.140 for Kelen-Tüdos method, and was estimated as r₁=0.37±0.0006 and r₂=0.64±0.0485 according to Fineman Ross equation. The average values estimated from the two methods showed that monomer reactivity ratio of benzyl methacrylate was a slightly high in comparison to HBPPMA. The copolymer system showed an azeotropic point, which is equal to M _BzMA =m _BzMA =0.43. DSC measurements showed that the T_g’s of poly(HBPPMA) and poly(BzMA) were 84 °C and 73 °C, respectively. The T_g in the copolymer system decreased with increase in benzyl methacrylate content. The decomposition temperature of poly(BzMA) and poly(HBPPMA) occurs in a single stage at about 207 °C and 260 °C, respectively. Those of HBPPMA-BzMA copolymer systems are between decomposition temperatures of two homopolymers. The dielectric constant, dielectric loss factor and electrical conductivity were investigated depend on the frequency of the copolymers. The highest dielectric constants depending on all the studied frequencies were recorded for the poly(HBPPMA) and the copolymer containing the highest HBPPMA unit. The dielectric constant for P(HBPPMA) and P(BzMA) at 1 kHz are 6.56 and 3.22, respectively. Also, those of copolymer systems were estimated between these two values. Similarly, poly(HBPPMA) and copolymers, which are prepared under the same conditions show the dissipation factor and conductivity as well.  相似文献   

不同土壤条件下灰枣叶片与果实营养品质的相关性     

哈地尔·依沙克  木合塔尔·扎热  马合木提·阿不来提  吴正保  史彦江 《新疆农业科学》2018,55(7):1236-1244

【目的】研究不同土壤条件(沙土、沙壤土和粘土)下,成龄灰枣树果实膨大期叶片营养成分与果实成熟期果实营养成分和品质之间相关性,为不同土壤类型下有效提升灰枣果品提供理论依据。【方法】以盛果期灰枣树作为试材,测定其在果实膨大期叶片和成熟期果实中的P、K、Ca、Mg含量,以及果实VC、可滴定酸、可溶性糖、糖酸比和可溶性固形物含量等品质指标。【结果】三种土壤相比,沙土的叶片Ca含量和果实糖酸比均最高,分别为(24.381±1.830) g/kg、725.167±95.195,叶片K和Mg含量,果实P和K含量,果实可溶性糖和可溶性固形物含量均中等,其余测定指标均较低;沙壤土的叶片K含量、果实Ca和可滴定酸含量均最高,分别为(37.385±2.478) g/kg、(0.654±0.043) g/kg、(0.107±0.006)%,叶片P和Ca含量,果实Mg含量和果实VC含量均中等,其余测定指标均较低;粘土的叶片P和Mg含量,果实P、K和Mg含量,果实VC、可溶性糖和可溶性固形物含量均最高,分别为(2.622±0.134) g/kg、(7.125±0.484) g/kg、(1.168±0.061) g/kg、(11.327±0.528) g/kg、(0.422±0.015) g/kg、(15.182±2.763) mg/100 g、(70.875±3.230)%和(71.179±3.233)%,果实Ca含量、可滴定酸含量和糖酸比均中等,其余测定指标均较低。3种土壤类型条件下灰枣果实中P、K、Ca、Mg、VC、可滴定酸、可溶性糖、可溶性固形物含量上均存在一定的差异,但在果实营养品质指标与叶片营养元素含量间的相关性基本相似,其中沙土、沙壤土和粘土灰枣叶片中P含量与果实VC含量间均有显著正相关性,相关性系数依次为0.798、0.928和0.869。【结论】灰枣叶片中的营养元素含量与果实营养品质指标间呈现一定相关性,在土壤不同类型条件下的施肥管理中,应根据土壤肥力情况制定科学合理的施肥方案,才能达到增产优质目的。  相似文献   

Toxicity and electrophysiological effects of Spilanthes amella Murr. extracts on Periplaneta americana L.     

Habsah A. Kadir  Muhamad B. Zakaria  Abdul A. Kechil  Moh D. S. Azirun 《Pest management science》1989,25(4):329-335

The potential insecticidal activity of Spilanthes acmella Murr. (Compositae) extracts was assessed in this study. The extracts were shown to be toxic against adults of American cockroach, Periplaneta americana L. The active component in S. acmella extract was isolated and identified as N-isobutyl-2,6,8-decatrienamide (spilanthol). The results from topical application of spilanthol show that it has a high acute toxicity and spilanthol was the most potent compound when compared to three conventional insecticides. The potency was found to be 1.3, 2.6 and 3.8 times more toxic than carbaryl, bioresmethrin and lindane, respectively. Electrophysiological studies indicated immediate hyperexcitation followed by complete inhibition of the cockroach cercal nerve activity.  相似文献   

Optimization of a profile extrusion die for flow balance     

Oktay Yilmaz  Hasan Gunes  Kadir Kirkkopru 《Fibers and Polymers》2014,15(4):753-761

One of the problems encountered in the extrusion of plastic profiles is unbalanced flow at the die exit. It causes deformation of the extrudates at ambient and precludes the material transition through remaining stages of production process (calibration, cooling sections etc). In this paper, geometric parameters of a profile extrusion die are optimized using several objective function definitions by Simulated Annealing-Kriging Meta-Algorithm. Objective functions are defined based on the uniformity of velocity distribution at the die exit. For this, Computational Fluid Dynamics (CFD) simulations are performed for N=70 die geometries. Appropriate geometric parameters (t and L) of the die are variables for the optimization problem.  相似文献   

Off-axis tensile properties of multistitched plain woven E-glass/polyester composites     

Kadir Bilisik  Gaye Yolacan 《Fibers and Polymers》2014,15(3):589-598

The aim of this study was to understand the ±45 ° directional off-axis tensile properties of the developed two dimensional (2D) multistitched multilayer E-glass/polyester woven composites. It was found that the off-axis tensile strength of the unstitched structure was slightly higher than those of the multistitched structures. The reason was that the multistitching process caused the filament breakages. It was also found that when the stitching direction and stitching density in structures increased, their off-axis tensile modulus decreased. Therefore, stitching directions, stitching density and stitching yarn on the composite structures were considered as important parameters. All structures under the off-axis tensile load had normal deformation, or angular deformation or shrinkage in width. In addition, both the normal deformation and the shrinkages in width occurred in most of the two and four directional stitched structures. On the other hand, four directional Kevlar^® 129 yarn dense stitched E-glass/polyester structure showed only shrinkage in width after angular deformation. This could be considered as a new failure mode because of the multistitching. These results indicated that the stitching directions and density generally influenced the off-axis tensile properties of the multistitched E-glass/polyester woven composites.  相似文献   

低温对库尔勒香梨不同部位抗氧化酶活性的影响     

卡德·艾山  胡西旦·买买提  玛丽娅·沙塔尔 《农产品加工．学刊》2012,(6):74-76,85

为了解香梨不同部位的抗寒能力与抗氧酶活性是否具有相关性,以库尔勒香梨为材料,测定不同部位越冬过程中抗氧化酶活性的变化。结果表明,库尔勒香梨不同部位在越冬过程中体内SOD,POD,CAT活性有明显的变化。SOD活性变化总体规律都随温度的上升而降低,不同部位之间的SOD活性没有明显差异;各部位的SOD活性不同月份之间有明显的差异,在最为寒冷的1月份达到最高值,其中休眠芽的活性为最高。POD活性随温度的逐渐升高而上升,3月份达到最高,其中主干阳面和阴面的POD活性高于其他部位。阳面和阴面CAT活性随温度的提高而回升,2月份最低,休眠芽和枝条CAT活性均逐渐下降。  相似文献   

Diprosopus, craniorachischisis, arthrogryposis, and other associated anomalies in a stillborn lamb     

Cihan Ka?ar  Kadir ?zcan  ?smet Tak??  Kutlay Gürbulak  Hasan ?zen  Musa Karaman 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(4):429-431

Congenital malformations with multiple anomalies have been described infrequently in the veterinary literature. A stillborn male crossbred lamb with diprosopus, craniorachischisis, and arthrogryposis was examined macroscopically and histopathologically in this study. The left head was smaller than the right head. Micrencephaly, agnathia, and a rudimentary tongue, which was adherent to the palate, were present in the left head. Micrencephaly, brachygnathia superior, and cleft palate were present in the right head. Cerebellar agenesis and spinal cord hypoplasia were observed. The cerebrums and the spinal cord were covered with a tapering membranous structure. Neural and dermal tissues were noted to intervene upon microscopic examination of this structure. Disorganization of neurons was observed in both cerebrums, though it was more severe in the left one. This case demonstrates many congenital defects occurring together in a lamb.  相似文献   

Therapeutic and prophylactic efficacy of imidocarb dipropionate on experimental Babesia ovis infection of lambs   总被引：1，自引：0，他引：1  

Sevinc F  Turgut K  Sevinc M  Ekici OD  Coskun A  Koc Y  Erol M  Ica A 《Veterinary parasitology》2007,149(1-2):65-71

The objective of this study was to evaluate the therapeutic and prophylactic efficacy of imidocarb dipropionate (IMDP) against babesiosis and to determine specific antibodies against Babesia ovis in experimentally infected lambs. Thirty-six 6-month-old splenectomized lambs were used. The lambs were randomly divided into six groups with six animals each, and were intravenously inoculated with 50 mL B. ovis-infected erythrocytes as follows: group I (therapy group) was treated with IMDP (1.2 mg/kg body weight) starting on the day of onset of clinical signs of babesiosis after the inoculation; group II (untreated control animals) was not treated with any therapeutic treatment after the inoculation; groups III, IV, V and VI (prophylaxis groups) were administered IMDP (2.4 mg/kg body weight) 1, 2, 3 and 4 weeks before the inoculation, respectively. The animals were housed in a tick-proof room with water and food ad libitum up to the 30th day post-inoculation (PI). The lambs were monitored from the first day PI by recording the manifestation of clinical disease, rectal temperature, and the degree of parasitaemia. All the lambs became infected with B. ovis, except five animals from group III, which were treated 1 week prior to experimental infection. Other animals showed signs of acute clinical babesiosis. The animals treated with IMDP (group I) were able to clear the parasite from the blood circulation after 48 h post-treatment. The recrudescence of B. ovis was observed in two lambs 7 days after treatment, and they were treated with the second similar dose of the drug. Six lambs (1, 1, 2 and 2 lambs in group III, IV, V and VI, respectively) from the prophylaxis groups died within 7-17 days after showing high parasitaemia and clinical symptoms of the disease. Regardless of the clinical symptoms, 83.30% and 66.66% of the lambs which were administered IMDP 1-2 and 3-4 weeks before, were determined to be protected against the virulent field strain of B. ovis.  相似文献