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1.
中国东部亚热带青冈种群叶片的生态解剖   总被引:12,自引:0,他引:12  
运用生态解剖学的方法对我国亚热带东部分布的10个青冈种群叶片的解剖特征进行了比较分析,结果如下:①青冈叶片结构在种群间存在着广泛的差异,这种差异是青冈适应不同环境条件的结构基础。青冈叶片各部分结构特征在种群间的变化不晃同步的,变异系数(CV)在6.0%~20.5%之间;变异幅度最大的是栅栏组织和上角质膜厚度,最小的是下表皮厚度。②相关分析表明,温度和降雨是影响青冈叶片地理变异的主导因子,其中温度、  相似文献   

2.
华东地区青冈种群的等位酶变异   总被引:7,自引:0,他引:7  
华东地区6个青岗种群等位酶变异的检测结果表明,青冈种群的遗传变异较大,每位点含有的等位基因较多,平均为2.3个,种水平的平均每位点等位基因数目为2.4。种群水平有效等位基因数目为1.446,种水平为1.467。Hardy-Weinberg平衡检验表明,青冈种群中不少位点偏离该平衡,其原因是种群内含有较多的纯合子,表现为多数位点的固定指数大于0,其中有9个位点的固定指数与0的偏差达到显著水平。  相似文献   

3.
中国大陆青冈分布区东缘大金山岛种群种子形态变异   总被引:3,自引:0,他引:3  
陈艳  沈浪  应向阳 《广西植物》2007,27(4):555-559
在大陆青冈分布区东缘的大金山岛种群中按不同坡向取样,旨在揭示相对均一条件下青冈种子的形态变异及变异的来源,以从不同侧面研究环境对形态变异的作用。大金山岛种群青冈种子的长度、直径和重量分别为1.557±0.128cm、1.175±0.112cm、1.321±0.310g,处于青冈种子正常分布范围内。单颗种子的长度、直径符合正态分布,而重量则明显偏离正态分布。不同坡向青冈种子间差异很小,表明微地形的影响较小;种群变异的来源株内和株间约各占一半,说明种子表型具有一定的可塑性,主要由于种子处于植株不同部位的缘故。  相似文献   

4.
余甘子天然居群果实形态变异研究   总被引:2,自引:0,他引:2  
为了从数量性状上分析余甘子天然居群果实表型性状在居群间和居群内的变异,在云南省选取了6个余甘子天然居群,分别测量了其8个果实表型性状并作比较分析。结果显示:(1)余甘子果实表型性状在居群间和居群内存在着较丰富的变异,8个果实性状在居群间的F值为20.17~35.21,部分差异达到显著水平;居群内的F值为1.27~3.07,差异均达到极显著水平。(2)余甘子居群内的平均表型变异接近90%,是余甘子果实表型遗传变异的主要来源。(3)余甘子表型性状的变化与生态和地理因子显著相关;主成分分析结果显示,单果重、果实横径、外果皮重、果核宽、果核重等5个表型性状指标是反映滇西北余甘子果实表型差异的主要因素。  相似文献   

5.
青冈种的能量积累   总被引:1,自引:1,他引:1  
  相似文献   

6.
洪水干扰对青冈群更新的影响   总被引:4,自引:0,他引:4  
本文在安徽黄山选择位于溪谷,受洪水干扰程度不同的3个样地,调查青冈种群的更新特征,结论如下:1.从幼苗数量来看,受洪水影响最轻的样地3个最多,密度为0.5825株m^-2,洪水影响最严重的样地1数量最少,密度仅为0.1150株m^-1,从幼苗性质来看,样地1萌生苗比率最高,3个样地中,随着高度级别增加,萌生苗的比例也增加。2.萌生苗高度的分布接近于对称的低峰分面  相似文献   

7.
本文通过调查统计和实验,对青冈种群动态进行了初步研究,包括种子库动态、种子萌发、无性繁殖以及密度调节等。研究表明,青冈种子量较大,但只有少数能发育成幼苗;有性繁殖和无性的克隆生长相互配合达到种群较高的繁殖效率;种群内个体的自疏定律说明,较成熟(40年左右)的青冈种群的增长速度已减慢。  相似文献   

8.
沙拐枣果实形态变异的数值分析   总被引:1,自引:0,他引:1  
研究利用新疆、甘肃河西、宁夏沙坡头地区采集的头状沙拐枣(Calligonum caput-medusae)、红皮沙拐枣(C.rubicundum)、白皮沙拐枣(C.leucocladum)、泡果沙拐枣(C.junceum)、河西沙拐枣(C.potaninii)和蒙古沙拐枣(C.mongolicum)果实的形态性状指标,应用双因素重复方差分析法,对不同种群间果实的形态变异进行了研究,得出红皮沙拐枣、蒙古沙拐枣、白皮沙拐枣、泡果沙拐枣下不同种群间果实的形态变异差异显著,头状沙拐枣、河西沙拐枣果灾的形态变里差异不显著,用系统聚类分析,对各种群间的相似性进行了研究。  相似文献   

9.
青冈常绿阔叶林主要树种叶形基本上都为椭圆形,叶面积在15-40cm2/叶之间,属于中型叶和小型叶;在同一植株上,青冈叶片的大小很好地符合正态分布规律,石栎则近似于负二项分布,甜槠和木荷接近正态分布;主要树种叶的大小是优势种青冈>次优势种石栎>其它伴生种,这在群落结构分化中具有适应意义,即其“生长策略”不同;同一树种叶片大小为中层木叶片>上层木叶片;春夏换叶之前,叶大小和叶重达到第一高峰,秋冬季出现第二峰,叶比重为秋、冬季>春、夏季,这是常绿植物对季节性不利气候(冬季寒冷,夏季高温伏旱)的一种生态适应。  相似文献   

10.
中国荞麦属果实形态特征   总被引:7,自引:0,他引:7  
应用解剖镜和扫描电镜对中国产荞麦属Fagopyrum Mill.8种1变种的果实形态和微形态特征进行了观察。结果表明这些种类的果实可分为3类:(1)果实三棱锥状,表面不光滑,无光泽,具皱纹网状纹饰,此种类型的植物有苦荞麦、金荞麦。(2)果实卵圆三棱锥状,表面光滑,有光泽,具条纹纹饰,此种类型的植物有荞麦、长柄野荞麦、线叶野荞麦。(3)果实卵圆三棱锥状,表面光滑,有光泽,具大量的瘤状颗粒和少数模糊的细条纹纹饰,此种类型的植物有硬枝野荞麦、细柄野荞麦、小野荞麦、疏穗小野荞麦。研究结果认为金荞麦与栽培种苦荞麦关系较近。  相似文献   

11.
Abstract The present study uses differences among frugivore faunas of the southern hemisphere landmasses to test whether frugivore characteristics have influenced the evolution of fruit traits. Strong floristic similarities exist among southern landmasses; for example, 75% of New Zealand vascular plant genera also have species in Australia. However, plants in Australia and South America have evolved in the presence of a range of mammalian frugivores, whereas those in New Zealand, New Caledonia and the Pacific Islands have not. In addition, the avian frugivores in New Zealand and New Caledonia are generally smaller than those of Australia. If frugivore characteristics have influenced the evolution of fruit traits, predictable differences should exist between southern hemisphere fruits, particularly fruit size and shape. Fruit dimensions were measured for 77 New Zealand species and 31 Australian species in trans‐Tasman genera. New Zealand fruits became significantly more ellipsoid in shape with increasing size. This is consistent with frugivore gape size imposing a selective pressure on fruit ingestability. This result is not a product of phylogenetic correlates, as fruit length and width scaled isometrically for Australian species in genera shared with New Zealand. Within‐genus contrasts between New Zealand and Australian species in 20 trans‐Tasman genera showed that New Zealand species have significantly smaller fruits than their Australian counterparts. Within‐genus contrasts between New Zealand and South American species in nine genera gave the same result; New Zealand species had significantly smaller fruits than their South American counterparts. No difference was found in fruit size or shape between New Zealand and New Caledonia congeneric species from 12 genera. These results are consistent with the broad characteristics of the frugivore assemblage influencing the evolution of fruit size and shape in related species. The smaller‐sized New Zealand frugivore assemblage has apparently influenced the evolution of fruit size of colonizing taxa sometimes within a relatively short evolutionary timeframe.  相似文献   

12.
《植物生态学报》1958,44(8):828
研究植物功能性状变异以及不同性状之间的关系, 有助于了解植物对环境的适应策略, 对揭示群落构建和生物多样性维持机制具有重要意义。本研究以桂林岩溶石山青冈群落18种主要木本植物为研究对象, 采用单因素方差分析、混合线性模型以及Pearson相关分析和主成分分析等方法探讨了不同生长型和生活型物种的9个枝、叶功能性状(叶绿素含量、叶片厚度、叶面积、叶干质量、比叶面积、叶干物质含量、叶组织密度、小枝干物质含量和小枝组织密度)的变异与关联。结果表明: (1) 9个功能性状的变异程度不同, 叶面积和叶干质量的种内和种间变异系数最大, 小枝干物质含量和小枝组织密度的种内和种间变异系数最小。(2)在生长型水平上, 乔木、灌木和木质藤本的绝大部分功能性状差异显著。(3)对于不同生活型植物, 除叶面积和比叶面积为落叶植物显著大于常绿植物外, 其余7个功能性状皆为常绿植物显著大于落叶植物。(4)不同生长型和生活型植物功能性状的种内和种间变异大小存在差异, 除部分植物功能性状在一些功能型上表现为种内变异高于种间变异, 其余功能性状的种间变异皆高于种内变异。(5)各功能性状之间关系在个体水平和物种水平大致相同, 但是个体水平上的显著相关比例高于物种水平。研究发现, 植物功能性状的种间变异基本高于种内变异, 但种内变异不容忽略。此外, 不同生长型和生活型物种采取不同的生态策略来适应喀斯特生境。今后的研究应基于个体水平采样并结合环境因子从生长型和生活型等不同功能型角度上深入探究植物功能性状在种内和种间等不同尺度上的变异与关联。  相似文献   

13.
Cyclobalanopsis glauca (Thunb.) Oerst., which belongs to China-Japan subtype of East Asia district, is a evergreen broadleaved tree of Fagaceae. It is distributed widely in the subtropical region of China and also in Japan, Korea, India, Burma, etc. According to the data on geographical distribution of this species collected extensively, the indexes of vegetation-climate interaction which used widely in the world were calculated. These indexes include Kira' s water-temperature indexes, Penman's formula, Thornthwaite's indexes and climatic classification, Holdridge's life zone classification system, annual average temperature, mean temperature in January, mean temperature in July, maximum temperature, minimum temperature, ≥10 ℃ accumulated temperature and precipitation. The relationships between geographical distribution of Cyclobalanopsis glauca and climate in China has been analysed and the Kira's water-temperature indexes on the distributional upper limit, lower limit and north limit have been discussed. The relation of species versus climate in historial period and the relation of species versus climate in historial period have also been discussed according to palynological and written records. The potential change of the tree species distributional area under elevated CO2 concentration has been forecast based on Holdridge' s indexes of life zone classification system and GCM models' conclusions.  相似文献   

14.
研究植物功能性状变异以及不同性状之间的关系, 有助于了解植物对环境的适应策略, 对揭示群落构建和生物多样性维持机制具有重要意义。本研究以桂林岩溶石山青冈群落18种主要木本植物为研究对象, 采用单因素方差分析、混合线性模型以及Pearson相关分析和主成分分析等方法探讨了不同生长型和生活型物种的9个枝、叶功能性状(叶绿素含量、叶片厚度、叶面积、叶干质量、比叶面积、叶干物质含量、叶组织密度、小枝干物质含量和小枝组织密度)的变异与关联。结果表明: (1) 9个功能性状的变异程度不同, 叶面积和叶干质量的种内和种间变异系数最大, 小枝干物质含量和小枝组织密度的种内和种间变异系数最小。(2)在生长型水平上, 乔木、灌木和木质藤本的绝大部分功能性状差异显著。(3)对于不同生活型植物, 除叶面积和比叶面积为落叶植物显著大于常绿植物外, 其余7个功能性状皆为常绿植物显著大于落叶植物。(4)不同生长型和生活型植物功能性状的种内和种间变异大小存在差异, 除部分植物功能性状在一些功能型上表现为种内变异高于种间变异, 其余功能性状的种间变异皆高于种内变异。(5)各功能性状之间关系在个体水平和物种水平大致相同, 但是个体水平上的显著相关比例高于物种水平。研究发现, 植物功能性状的种间变异基本高于种内变异, 但种内变异不容忽略。此外, 不同生长型和生活型物种采取不同的生态策略来适应喀斯特生境。今后的研究应基于个体水平采样并结合环境因子从生长型和生活型等不同功能型角度上深入探究植物功能性状在种内和种间等不同尺度上的变异与关联。  相似文献   

15.
In this work the analogies and differences in shape and size between a rural school population (6–14 aged) of the Lozoya-Somosierra region (Madrid) and several recent and past Spanish populations from different environments have been studied. The results show the growth trend as well as the influences of ecological and socioeconomical factors. Paper presented at the 4th congress of the European Anthropology Association (Florence, Sept. 1984).  相似文献   

16.

Background and Aims

Some otherwise promising selections of Actinidia chinensis (kiwifruit) have fruit that are too small for successful commercialization. We have therefore made the first detailed study in diploid kiwifruit of the effects of chromosome doubling induced by colchicine on fruit size, shape and crop loading.

Methods

Flow cytometric analysis of young leaves and chromosome analysis of flower buds and root tips was used to confirm the stability of induced autotetraploids. Fruit weight, size and crop load were measured in the third year after planting in the field and for three consecutive years. DNA fingerprinting was used to confirm the origin of the material.

Key Results

There was a very significant increase in fruit size in induced autotetraploids of different genotypes of A. chinensis. With the commercially important diploid cultivar ‘Hort16A’, most regenerants, Type A plants, had fruit which were much the same shape as fruit of the diploid but, at the same fruit load, were much larger and heavier. Some regenerants, Type B plants, produced fruit similar to ‘fasciated’ fruit. Fruit of the autotetraploids induced from three female red-fleshed A. chinensis selections were also 50–60 % larger than fruit of their diploid progenitors. The main increase in fruit dimensions was in their diameters. These improved fruit characteristics were stable over several seasons.

Conclusions

Chromosome doubling has been shown to increase significantly fruit size in autotetraploid A. chinensis, highlighting the considerable potential of this technique to produce new cultivars with fruit of adequate size. Other variants with differently shaped fruit were also produced but the genetic basis of this variation remains to be elucidated. Autoploids of other Actinidia species with commercial potential may also show improved fruit characteristics, opening up many new possibilities for commercial development.  相似文献   

17.
? Premise of the study: We isolated and characterized polymorphic microsatellite loci in Cyclobalanopsis glauca (Fagaceae), an evergreen broadleaved monoecious tree, to provide tools for analyzing parentage and mating system. ? Methods and Results: Thirteen polymorphic microsatellite markers were developed and tested in three C. glauca populations. The number of alleles per locus varied from two to 22. The observed and expected heterozygosities within populations were 0.000-0.967 and 0.033-0.949, respectively. ? Conclusions: These polymorphic primers showed high levels of polymorphism within tested populations, and can be used in parentage analysis and mating system estimation of C. glauca.  相似文献   

18.
安徽黄山西部青冈种群小地理范围的遗传分化   总被引:18,自引:0,他引:18  
采用垂直板型聚丙烯酰胺凝胶电泳研究了黄山西部青冈〔Cyclobalanopsisglauca(Thunb.)Oerst.〕种群小地理范围的遗传分化。黄山2个亚种群之间基因频率基本没有差异,基因多样性平均为0.1826,小岭和钓桥亚种群分别有2个和1个位点存在显著的杂合子不足的现象。亚种群之间的遗传分化程度很低(GST=0.976%),主要是由于小地理范围的生境异质性程度低和较大的基因流(平均为173)造成的。  相似文献   

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