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1.
为明确污泥对草地早熟禾(Poa pratensis)抗氧化酶和耐旱性的影响,本试验采用裂区设计,主处理为充分浇水、干旱2种水分条件,副处理包括对照(硝酸铵提供75mg·kg~(-1)的氮素)、半污泥(硝酸铵和污泥各提供1/2的草地早熟禾所需的75mg·kg~(-1)的氮素)和全污泥(污泥提供75mg·kg~(-1)的氮素)。结果表明,与对照相比,充分浇水条件下,全污泥和半污泥均能显著提高草地早熟禾的坪观质量、根重及可溶性糖含量,降低叶片萎蔫度;干旱胁迫下,全污泥和半污泥均能显著提高草地早熟禾的坪观质量、相对含水量并降低其叶片萎蔫度,这表明施用污泥可以促进草地早熟禾在干旱胁迫下的生长状态。充分浇水时,全污泥和半污泥处理的草地早熟禾试验后期叶片超氧化物歧化酶(SOD)活性与对照相比显著提高了39.5%和50%(P0.05),且半污泥处理叶片过氧化物酶(POD)活性也比对照显著增加了14.2%;极度干旱(土壤含水量为25%)时,施用全污泥和半污泥的草地早熟禾叶片SOD、过氧化氢酶(CAT)活性均显著升高,且半污泥处理的草地早熟禾叶片POD活性显著提高,为对照的1.3倍。研究结果表明,生物污泥可以增强草地早熟禾耐旱性,提高其细胞抗氧化能力。  相似文献   

2.
采用不同程度的水分胁迫与5个不同钾素水平进行交互处理,以草地早熟禾品种Merit为试材,研究钾对水分胁迫下草地早熟禾生理特性及草坪质量的影响。结果表明:同一钾素浓度下,水分胁迫显著(P0.05)降低草地早熟禾草坪质量、叶绿素含量、根系活力、抗氧化酶活性,显著(P0.05)增加草地早熟禾电导率及丙二醛、脯氨酸、可溶性糖含量。同一水分条件下,随着钾素浓度的增加,草地早熟禾草坪质量、叶绿素含量、根系活力、脯氨酸含量、抗氧化酶活性先升高后降低,电导率、丙二醛含量先降低后升高,可溶性糖含量不断升高。在重度水分胁迫下,与0mmol/L钾处理相比,9mmol/L钾处理下Merit的POD、SOD、CAT活性分别上升了68%、35%、65%,对于缓解干旱、提高草坪耐受性和坪用质量效果最好。  相似文献   

3.
乙烯利对干旱胁迫下草地早熟禾生理指标的影响   总被引:1,自引:0,他引:1  
以草地早熟禾(Poa pratensis)‘Nuglade'品种为试验材料,研究叶片喷施乙烯利对草地早熟禾在水分充足、干旱及复水恢复3种处理下叶片电解质渗透率、叶绿素、可溶性蛋白、丙二醛(MDA)等生理指标的影响。结果表明,乙烯利与对照组(CK)相比,乙烯利在干旱胁迫下保持更高的叶片相对含水量23.5%(对照为11.5%)和更低的电解质渗透率68.1%(对照为90.7%)及MDA含量53.90μmol·g~(-1)(对照检查131.62μmol·g~(-1)),且复水后的电解质渗透率恢复程度更好;此外乙烯利处理提高了复水恢复过程草地早熟禾的可溶性蛋白含量;说明,叶片喷施乙烯利能够缓解草地早熟禾的干旱胁迫损伤,并促进干旱后的复水恢复。  相似文献   

4.
摘要:通过测定人工模拟干旱缺水条件下,不同浓度硅处理后草地早熟禾(Poa pratensis)品种蓝宝石(Sapphire)总蒸散量、叶片相对含水量、叶片相对电导率、草坪质量、根干质量、根活性指标变化,研究了硅对干旱胁迫条件下草地早熟禾形态及生理特性的影响。结果表明,干旱胁迫下草地早熟禾的总蒸散量、叶片相对含水量、草坪质量、根干质量、根活性较对照(充分灌水)明显下降,而叶片相对电导率明显上升。在对照处理下,各浓度硅对总蒸散量、叶片相对含水量、草坪质量、根干质量、根活性、叶片相对电导率均没有显著影响;而在干旱胁迫下,硅能明显促进草地早熟禾总蒸散量、叶片相对含水量、草坪质量、根干质量、根活性升高,促进叶片相对电导率明显下降,且以浓度为2.14 mmol/L时效果最佳。  相似文献   

5.
不同种类早熟禾苗期抗旱性综合评价   总被引:1,自引:0,他引:1  
在干旱半干旱地区,水分是牧草生长的主要限制因素之一,探究牧草苗期阶段的抗旱性特征对干旱地区牧草引种筛选具有重要意义。本研究选取了青海省海北地区的8份早熟禾属(Poa L.)种质材料,于苗期分别对其进行干旱胁迫处理,并测定干旱胁迫后第5d和第10d各草种叶片的细胞膜透性及丙二醛(MDA)、脯氨酸和叶绿素的含量,运用Fuzzy数学中隶属函数法对8种早熟禾进行抗旱性综合评判。结果表明:随着胁迫时间的延长,8份早熟禾属种质材料的叶绿素含量均显著下降(P0.05),细胞膜透性、脯氨酸和MDA含量则显著增加(P0.05)。综合评价结果表明:不同种质材料间苗期抗旱性差异较大,由强到弱依次为:草地早熟禾高原早熟禾山地早熟禾光稃早熟禾波伐早熟禾早熟禾莫若波利草地早熟禾冷地早熟禾,草地早熟禾和高原早熟禾抗旱性较强,更适合在干旱地区种植。  相似文献   

6.
不同早熟禾品种对干旱胁迫的生理响应及抗旱性评价   总被引:5,自引:0,他引:5  
为鉴定评价早熟禾幼苗抗旱性,将14个早熟禾品种的种子经消毒后播种在塑料花盆中,出苗后间苗,2~3个真叶定株,每盆留生长一致、分布均匀的幼苗15株,定期浇水,以保证幼苗的正常生长。待生长到3~4个真叶时进行干旱处理,依据Michel公式计算不同水势所需的PEG-6000的量,然后加入PEG-6000溶液进行干旱处理,处理的水势梯度为0 MPa(即为对照),-0.3,-0.6,-0.9和-1.2 MPa。处理后每2 d进行称重补水以维持溶液浓度。设干旱处理与对照(正常浇水)两组,对14个早熟禾品种幼苗进行模拟干旱胁迫,4次重复。测定叶绿素(CHL)含量、丙二醛(MDA)含量、脯氨酸(Pro)含量、过氧化物酶(POD)以及超氧化物歧化酶(SOD)活性等生理生化指标。结果表明,随着干旱胁迫的加剧,早熟禾幼苗叶片CHL含量呈下降趋势;Pro含量、MDA含量、SOD活性总体呈上升趋势;POD活性总体呈先降再升后降的趋势;利用隶属函数分析得出14个早熟禾品种的抗旱性强弱顺序依次为:3号恩托佩草地早熟禾>10号细叶早熟禾>1号优异草地早熟禾>2号斗士草地早熟禾=9号蓝钻草地早熟禾>7号草地早熟禾>11号草地早熟禾>4号草地早熟禾>5号瓦巴斯草地早熟禾>8号早熟禾=13号肯塔基草地早熟禾>14号草地早熟禾>6号莫诺波利草地早熟禾=12号菲尔津草地早熟禾。  相似文献   

7.
采用-0.1,-0.3,-0.5和-0.7 MPa的聚乙二醇6000(PEG-6000)模拟不同程度的干旱胁迫,在萌发期分别处理8份野生草地早熟禾(Poa pratensis)种质和2个商用品种21 d,并测定发芽率、发芽势和活力指数等7个鉴定指标,并以其相对值作为评价指标,利用隶属函数法和聚类分析对供试的10份种质材料进行了综合评价和分类,同时,对各鉴定指标在草地早熟禾萌发期抗旱性评价中的作用进行了比较分析。结果表明,用于草地早熟禾萌发期抗旱性研究的适宜PEG-6000浓度为-0.1~-0.3 MPa,种子活力指数和发芽率受干旱胁迫的影响较大,且与抗旱性的关系最为密切,可作为草地早熟禾种质萌发期抗旱性鉴定的重要指标。10份种质材料抗旱性由强到弱依次为:秦州 > 西和 > 陇西 > 安定 > 渭源 > 天祝 > 榆中 > MidnightⅡ > 清水 > Baron;聚类分析可把供试材料按抗旱性强弱分为三类,其中清水和Baron属于干旱敏感种质;安定、渭源和MidnightⅡ等属于中等抗旱种质;秦州、西和和陇西属于抗旱种质,可作为抗旱育种材料。  相似文献   

8.
采用3个不同水分梯度和3个不同氮素浓度的交互处理,研究草地早熟禾细胞抗氧化酶活性等相关生理生化指标与草坪质量的变化。结果表明:在轻度水分胁迫×中氮处理下,草地早熟禾SOD、POD及CAT酶活性均较高,MDA含量相对较低;草地早熟禾的细胞抗氧化能力与叶片可溶性蛋白含量、叶绿素含量、叶片含水量之间不同程度的正相关;草地早熟禾坪用质量与叶片叶绿素含量、可溶性蛋白含量及含水量间呈显著一元线性关系;同等干旱胁迫下,适当增施氮素可提高叶片可溶性蛋白含量、叶绿素含量和含水量,即干旱胁迫导致草地早熟禾坪用质量的降低可通过施适量氮素得到补偿。  相似文献   

9.
干旱条件下硅对草地早熟禾生长初期的影响   总被引:5,自引:3,他引:2  
在聚乙二醇(PEG-6000)模拟干旱胁迫条件下,研究了5种硅肥(Na2SiO3)浓度对草地早熟禾Poapratensis种子萌发以及幼苗生长初期形态及生理指标的影响.结果表明:干旱胁迫会显著抑制早熟禾种子的萌发.使其幼苗萎蔫失水、叶片相对含水量降低、生物量下降;干旱胁迫下,硅可以显著提高早熟禾种子的发芽率和发芽势.并且干旱胁迫程度愈大硅的作用效果愈显著,同时硅能有效改善幼苗根系生长状况,利于早熟禾对养分和水分的吸收,提高叶片相对含水量和生物量,从而起到缓解干旱伤害的作用.但超过一定浓度时,硅也会抑制早熟禾的生长.  相似文献   

10.
通过发芽试验,探讨不同浓度五氨基乙酰丙酸(5-ALA)对Cd胁迫、盐胁迫及干旱胁迫下草地早熟禾(Poa pratensis)种子萌发及幼苗生长的影响。本试验以草地早熟禾‘午夜’(Poa pratensis‘Midnight’)品种为材料,在Cd(2mg·L~(-1)),NaCl(50 mmol·L~(-1)),PEG(15%)3种处理下分别施加不同浓度的5-ALA(0,5,25,50,100mg·L~(-1)),分析了不同处理下种子发芽势、发芽率、可溶性蛋白等指标。结果表明:不同胁迫下较低浓度(5,25mg·L~(-1))5-ALA均能提高种子的发芽势、发芽率、芽长、根长等指标,而较高浓度(50,100mg·L~(-1))的5-ALA起抑制作用。综合比较4种不同浓度的5-ALA发现,25mg·L~(-1)对胁迫的缓解效应最优,其Cd胁迫下发芽势、发芽率分别比对照增加了21%,33.67%;NaCl胁迫下发芽势、发芽率分别增加了22.67%,23.67%;PEG模拟干旱胁迫下发芽势、发芽率分别增加了15.33%,10.67%。25mg·L~(-1) 5-ALA对NaCl,PEG胁迫下可溶性蛋白含量提高显著,分别提高了6.5和3.8μg·g-1,对于Cd胁迫,可溶性蛋白含量虽有提升但不显著。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
14.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

17.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

18.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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