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1.
利用扫描电子显微镜观察10份柠檬种质的花粉形态,500倍观察花粉粒群体,3000倍观察赤道面和极面,10000倍观察外壁纹饰。结果表明:10份柠檬种质的花粉类型均属于单粒花粉,外观形态为长球形、近球形和扁球形三类,大小等级为小的花粉,萌发孔沟4~5条,沟长均直达两极,沟沿极轴方向等距环状分布,外壁纹饰均属于网状雕纹。10份柠檬种质两两之间在花粉极轴长、赤道轴长、萌发沟数量及外壁纹饰上,均存在一个或者一个以上的极显著差异或显著差异,因此,可作为不同柠檬种质之间鉴定的依据。  相似文献   

2.
!.丝瓜花粉花粉近橄榄形,外壁具网状雕纹,3孔沟。2.芥菜花粉花粉粒为椭园形,外壁具粗网状雕纹,3孔沟。3.油菜花粉花粉粒为椭园形,外壁具网状雕纹,3孔沟。4.菊花花粉花粉粒近球形,外壁具刺状雕纹,3孔沟。5.玉米花粉花粉近球形,外壁雕纹不明显。6.蒲公英花粉花粉近球形,外壁表面具大网,网脊有刺。7.苹果花粉花粉粒为长球形,外壁表面具网状雕纹,3孔沟。8.南瓜技粉在粉粒为球形.外壁表面具$IJ状雕封。散孑l。花粉形态特征的电镜扫描观察@王维义$杭州大学生物系 @蔡继炯$浙江测试所~~  相似文献   

3.
本文选取7个泡核桃主栽品种,利用扫描电子显微镜在1300倍下观察花粉粒形态,9000倍观察萌发孔和外壁纹饰。结果表明,7种泡核桃品种均属单粒花粉,花粉形态一致,为近球形,表面布有萌发孔,外壁纹饰为颗粒状雕纹,与同科同属新疆栽培的普通核桃形态相似,与同科不同属的山核桃形态存在很大差异,且不同泡核桃品种间的花粉和萌发孔大小等存在显著差异或极显著差异,以此可作为泡核桃品种鉴定、划分和判断亲缘关系远近的依据。  相似文献   

4.
明确黄皮种质资源花粉的形态特征及种质间的亲缘关系,为确定黄皮种质资源的系统分类鉴定提供孢粉学依据。以来自福建省11个产地的33份黄皮种质花粉为试材,经固定、清洗、逐级脱水、干燥、喷金镀膜等处理,采用JSM-6380LV型扫描电子显微镜观察花粉的形态结构,分别选取有代表性的视野观察黄皮花粉群体(放大800倍)、花粉个体(放大3500倍)、花粉赤道面中部的外壁纹饰(放大8000倍)等方面的超微形态特征分别进行显微照相和相关指标测定,将试验所得的综合数据进行统计分析和聚类分析。试验结果表明,观察的黄皮花粉为近球形(0.88

相似文献   


5.
内蒙古西部白刺属植物花粉形态属于长球形—超长球形,萌发器官类型为3孔沟,表面纹饰为条纹状和网状纹饰复合型;种子形态为卵形,表面有孔穴和槽;以上特征种间有明显的差异。  相似文献   

6.
利用扫描电镜和光学显微镜对我国岩黄耆属21种植物的花粉形态作了系统观测。结果表明,21种岩黄耆属植物的花粉为长球形,大多具3沟,少数为3拟孔沟,沟长达两极,极面观三裂圆形,赤道面观长球形,沟膜外突或不外突,极轴长15.6~30.25μm,赤道轴长9.0~19.5μm,极轴/赤道轴为1.28~1.85,大小为22.16μm(18.03~27.55μm)×14.32μm(12.13~18.76μm),表面具穿孔状、网穴状、拟网状和网状纹饰。岩黄耆属植物花粉的大小、沟膜和外壁纹饰变异较大,这种变异与该属植物的生态地理分布有关。同时,结果显示岩黄耆属与藏豆属较驴食草属更为近缘,但对其系统位置及亲缘关系的确立,还需要更多的资料和证据。  相似文献   

7.
本文利用光镜和扫描电镜以内蒙古地区分布的蒺藜科(Zygophyllaceae)中的5属7种植物的花粉形态作了观察,结果表明,该科植物的花粉粒以长球形,圆球形为主,属中等大小,萌发器官多为3孔沟,外壁表面纹饰以网状,条纹状最为常见,同时,观察结果还表明,蒺藜科不同属的植物花粉形态差异显著,而同属不同种间差异则较小,本文认为花粉形态特征在该科植物分类上具有重要的参考价值,尤其可作为属间的分类依据。  相似文献   

8.
37个早熟禾品种的花粉形态及其分类学意义   总被引:1,自引:0,他引:1  
朱琨  张璐  陈雅君  张楚涵  周阳  李雪 《草地学报》2011,19(1):114-121
为探讨花粉形态特征在早熟禾(Poa L.)品种分类上的意义,用扫描电镜对‘巴林’、‘巴润’、‘肯塔基’等37个早熟禾品种的花粉进行观察,比较不同品种的花粉外壁纹饰、形状、极轴和赤道轴长度、极轴与赤道轴比值、花粉孔径大小等花粉形态特征。结果表明:所有品种的花粉形状均为近球形或圆球形,具有1个萌发孔,但是不同品种的花粉大小和表面纹饰特征均存在显著差异(P<0.05),按纹饰特征可将37个品种分为粗糙型、颗粒型、瘤状型和皱波状型4大类型,其演化趋势为粗糙型→颗粒型、瘤状型→皱波状型,皱波状型花粉纹饰品种最进化。利用DPS数据处理系统对花粉大小进行孢粉学聚类分析,也可将37个早熟禾品种分为4大类群,通过演化趋势分析得知2种分类方法基本一致,可为早熟禾品种分类提供依据,为新品种的选育提供指导。  相似文献   

9.
蔡萍  宛涛  伊卫东  刘辉  张佳琦 《草地学报》2019,27(3):779-783
以内蒙古特有乡土沙生植物乌丹蒿(Artemisia wudanica)为研究对象,采用扫描电镜(Scanning Electron Microscopy,SEM)技术,对其花粉形态进行了详细的观察描述,探索其花粉形态的二型性特点,完善其花粉形态细微特征。结果表明:乌丹蒿花粉粒有长球形和圆球形之分,花粉形态存在明显的二型性特征。长球形花粉赤道面观为椭圆形,极面观为三裂片圆形;大小平均为:23.28 μm×13.73 μm;萌发器官为3孔沟类型;表面纹饰为刺状-颗粒状复合纹饰。圆球形花粉赤道面为圆球形;极面为三裂圆形;萌发器官也是3孔沟类型;大小平均为:14.85 μm×13.80 μm;表面纹饰亦为刺状-颗粒状复合纹饰。除花粉粒的大小、极轴与赤道轴的比值(Polar axis/Equatorial axis,P/E)不同外,两种类型的花粉总体形态特征基本一致;细微性状主要差异表现在表面纹饰中刺的大小及刺与颗粒的排列密度等方面。  相似文献   

10.
刘鹏  马利超  王宇  刘志鹏 《草业学报》2015,24(1):107-114
野豌豆属牧草适宜在高寒和高海拔地区栽培,是我国高原牧区重要的蛋白饲料来源。该属有190个物种,4个亚属:Vicia,Cracca,Ervum和Faba。本研究从中国、美国、土耳其和叙利亚等11个国家收集了16份野豌豆属牧草种质,利用扫描电镜对这16份材料的花粉形态进行观察。结果表明,野豌豆属植物花粉均以单粒形式存在,极面观为三裂圆形和三角形,赤道面观为扁圆形、长椭圆形和椭圆形。三沟萌发孔,沟长深入两端;极轴长为(9.60±1.52)(30.40±2.07) μm,赤道轴长为(11.80±0.84)(38.20±0.84) μm。花粉的表面纹饰呈3种类型:网状纹饰,脑状纹饰和疣状纹饰。网状纹饰根据外壁纹饰疏松程度不同,又可分为2种亚类型:粗网状纹饰和细网状纹饰。本研究较为系统地观察了16个野豌豆属牧草的花粉形态,探讨了其系统分类学特性,为揭示野豌豆属种质资源的遗传多样性奠定了基础。  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.
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   

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.
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   

19.
<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   

20.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

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