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1.
【目的】系统分析来自不同种源蕨麻的种子表型性状,系统揭示蕨麻种子的性状变异程度和形态特征多样性。【方法】以30份不同种源蕨麻种子为材料,测定其长、宽、周长、厚度、长宽比以及千粒重等指标,并进行方差分析、相关性分析、聚类分析以及主成分分析。【结果】1)蕨麻种子6个性状均存在极显著差异(P<0.01),不同性状也存在丰富的变异,其中种子千粒重变异系数最大(23.91%),是筛选品种较重要的指标;2)种子厚度和种子千粒重与种子长度、种子宽度、种子长宽比以及种子周长都呈现了极显著的正相关(P<0.01),表明种子厚度和种子千粒重可以作为蕨麻优良品种筛选的重要指标;3) 30份种源种子可以聚类为5个类群,其中类群2和类群3的各指标量均较大,可以作为品种筛选的候选群体;4)主成分分析和综合评价表明,种子厚度、种子千粒重和种子长度是影响蕨麻种子性状的主要因素,而种源4的综合性状得分最高,为2.35,是最佳品种选育的候选。【结论】种源4为综合性状俱佳的种质,可以将其作为蕨麻新品种筛选的候选和主要种植的种源。研究结果可为蕨麻新品种选育提供该理论依据。  相似文献   

2.
对内蒙古不同生态区收集的22份野生山韭的株高、株丛直径、叶长、叶宽、单株叶片数、花序高度、花序宽度、小花数目、花葶长度、花梗长度、种子长、种子宽、种子厚和种子千粒重等14个表型性状进行观测,采用方差分析、主成分分析、聚类分析等方法进行了遗传多样性分析,以期筛选出适合内蒙古地区推广应用的优良种质,为山韭育种提供依据。结果如下:1)山韭种质表型性状变异程度较高,变异系数范围为11.9%~41.8%,其中叶片宽变异系数最大,种子厚最小,14个表型性状材料间的差异除叶片宽和单株叶片数达到显著(P0.05)水平,其余差异不显著;2)14个表型性状可归为5个主成分因子,累计贡献率达81.360%,可以反映14个表型性状的绝大部分相关信息,其中株高、种子长、种子宽、种子千粒重、叶片宽和单株叶片数等性状是造成表型性状差异的主要因素;3)14个表型性状间存在显著或极显著的相关性。4)采用欧氏距离系统聚类法可将22份山韭材料分为4大类,地理类别和性状相似的种质大部分能够聚为一类。  相似文献   

3.
河西走廊不同红砂天然群体种子表型性状相关性研究   总被引:1,自引:0,他引:1  
采用方差分析、多重比较、相关分析、聚类分析等多种分析方法对河西走廊红砂天然分布区10个群体种子千粒重、种子长、种子宽、种子长宽比4个表型性状进行研究,以系统揭示不同群体红砂种子表型性状的变异程度和变异规律。研究结果表明,4性状在群体间差异极显著(P<0.01),在群体内没有显著差异;4性状平均变异系数为0.019 3,变异幅度0.001 8~0.068 5,其中千粒重最大,为0.068 5,种子长最小,为0.001 8,各群体4性状平均变异系数最大的是张掖1,为0.048 4,最小的是酒泉2,为0.006 6;各性状变异来源以群体间为主,占到总变异的68%以上;各表型性状均呈现出以经度、纬度和海拔为主的梯度变异规律;通过对4个表型性状各测量值的聚类分析,将10个天然群体拟划分为4个类群。对不同群体红砂种子表型性状的研究,初步了解和掌握河西走廊红砂种子的变异趋势和变异规律,可为今后开展种质资源收集与保存、遗传评价及种质创新利用以及人工辅助更新及群体遗传多样性研究提供理论依据。  相似文献   

4.
选取分布于青海省柴达木盆地的12个枸杞自然群体,分别对其4个表型性状(种长、种宽、种子长宽比和千粒质量)进行统计分析,以便更好地选择并利用枸杞优良品种资源。结果表明:参试枸杞群体种子千粒质量、种长、种宽在群体间差异极显著(P0.01),种子长宽比差异显著(P0.05),各性状在群体内差异不明显;各群体种子千粒质量间的差异达到了极显著水平,参试群体在其他各性状上均差异显著;不同性状变异系数最大的驯化‘黑果枸杞’与变异系数最小的‘咖啡枸杞’的变异系数相差5倍,表现出丰富的多样性,根据参试枸杞丰富的自然变异,可初步推断其与遗传变异之间的联系;聚类分析中,以相近系数为12.5将0207与‘宁杞1号’分为1类,‘红果枸杞’与‘白果枸杞’分为第2类,其他参试群体分为第3类。说明枸杞种子表型是基因表达与所处环境交互作用的结果,与其他同类研究结果一致。  相似文献   

5.
本研究对22份百脉根(Lotus corniculatus)种质资源的11个表型性状指标进行多样性研究分析。结果表明:除种宽外,22份百脉根种质间的表型性状均存在显著变异,表型性状指标变异幅度为12.11%~69.48%,各表型性状之间存在显著或极显著相关性。主成分分析表明,茎长、株高、冠幅、种子周长、种子长、种子宽和种子长宽比的主成分载荷较高,是造成百脉根种质表型性状差异的主要因素。根据聚类分析将22份百脉根种质分为3个类群,其中,第Ⅰ类群种质的种子小,但植株高大,第Ⅱ类群种质的种子小且植株矮小,第Ⅲ类群种质的种子和种荚大但植株矮小。综合评价11和12号这2份种质资源整体表现优良,且归属于第Ⅲ类群,具有种荚和种子较大的特性,可作为选育种子高产品种的目标亲本利用。本研究结果可为百脉根的种质应用和品种选育提供理论参考。  相似文献   

6.
本研究以48份野豌豆属的14个种为研究对象,以17个种子表型性状来揭示野豌豆属表型性状的遗传多样性,并对其进行分类鉴定。结果表明:种子表型性状种间变异较大,数量性状中百粒重变异系数最大,为81.92%,种形指数的Shannon多样性信息指数最大,为1.94;质量性状中种脐颜色的变异系数最大,为75.12%,其Shannon多样性信息指数也最大,为1.56;主成分分析表明前6个主成分累计贡献率达86.09%;相关性分析表明种子长、种子宽、种子厚和百粒重相互之间呈极显著正相关关系(P<0.01);在相似性系数为0.79时可将试验材料分为5大类群。本研究中百粒重、种脐颜色、种皮颜色、种皮纹理、种脐长/种子长、子叶颜色、胚根基部斑纹、种脐形状、胚根宽/胚根长可作为该14种野豌豆属植物种间分类鉴定依据,并据此制作相应检索表,为野豌豆属的鉴定提供依据。  相似文献   

7.
郝峰  徐柱  闫伟红  李平  刘英  扈延成 《草地学报》2011,19(4):668-673
为了解不同草原生态区域扁穗雀麦(Bromus catharticus Vahl.)的形态变异及其亲缘关系,对17份种质材料的27个形态性状进行测定和分析。结果显示:其形态遗传变异较高,变异系数范围在9.13%~54.76%之间,变异系数较大的性状有小穗数、分蘖数、分枝着生小穗数、叶片长、秆直径、分枝长和株高等;变异系数较小的性状有穗节数、小穗轴节间长、小穗长、外稃长、内稃长、叶舌长、内稃宽、花药长、第二颖脉数、外稃宽等。叶片宽、分枝长、穗长、叶片长、秆直径、株高、小穗含小花数、小花数、小穗宽、花药长、小穗轴节间长等11个指标对总变异的贡献最大。并对27个性状进行了分类和性状间相关性聚类研究,17份材料聚类分析展示了不同材料间的亲缘关系。此形态变异研究为深入研究种质资源及育种提供了科学依据。  相似文献   

8.
种子特性是种子质量评价的基础。本文研究了28份羊草(Leymus chinensis)种质的颖果性状。结果表明:外稃和颖果长宽在种质间、地域间均存在显著差异;多数种质的內外稃都不易脱落,但外稃较內稃易于脱落;外稃长与颖果长、颖果长与千粒重、颖果宽与颖果比重极显著相关(P<0.01)。而内稃脱壳指数与外稃长及颖果长、千粒重与外稃宽均显著相关(P<0.05)。这些研究结果对羊草种质资源评价和利用具有参考价值。  相似文献   

9.
杨正禹  陆忠杰  张茂  董瑞 《草业学报》2021,30(11):87-97
胡枝子属植物是重要的豆科牧草,为了解胡枝子属植物种子表型性状遗传多样性,本研究对胡枝子属的Lespedeza juncea、Lespedeza cuneata、Lespedeza capitata和Lespedeza bicolor等16个种132份种质的种子数字图像信息,包括种子长(SL)、种子宽(SW)、长宽比(SL/SW)、种子周长(Pe)、种子厚(ST)、种脐长(HL)、百粒重(SY)等7个种子形态学特征进行分析.使用GenStat中的REML分析以及聚类分析和主成分分析相结合的模式分析方法.结果显示:132份胡枝子种质及L.juncea中所有种质间的种子性状都存在显著(P<0.05)差异.L.capitata和L.bicolor中除性状SL/SW,L.cuneata中除性状SL/SW和Pe外,其余性状在种质间都存在显著(P<0.05)差异.测量的7个性状中,变异系数(CV)均大于5%,最高为61.95%,最小为5.42%.132份种质及4个种的SY、ST、Pe的R值均大于0.9,表明遗传稳定性强,可作为育种工作的参考指标.本研究可为胡枝子属植物分类、种质资源改良及遗传多样性研究奠定基础.  相似文献   

10.
肥料和除草剂混施对老芒麦构件组成及生物量结构的影响   总被引:2,自引:0,他引:2  
以不同尿素和磷酸二氢钾含量组合阔叶除草剂混施,研究不同组合对川草2号老芒麦的影响,结果表明:混施对根、茎、叶、花序等构件的质量与数量性状都有影响,茎性状指标的变异系数由大到小为分蘖密度节直径节间长茎直径单蘖节数,不同混施组合间分蘖密度、节直径、节间长存在极显著差异;混施组合间叶长、叶宽差异极显著;对花序性状的影响为花序厚花序宽小穗数生殖枝比例花序柄长小花数花序长;组合间根系深度、分布范围都存在显著差异;对根、茎、叶、花序生物量的累积均有影响,株高、鲜草产量、干草产量变异系数分别为12.42%、29.98%、25.93%,组合1、组合2和组合6增产效果明显;混施对种子产量影响极显著,组合1、组合5和组合6适合在种子生产中推广;杂草的种类、单位面积杂草生物量、杂草占生物量的比例都低于对照。肥料与除草剂混施可减少田间作业次数,降低管理成本,达到增肥和除草的双重效果,值得在生产中推广与应用。  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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