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1.
云杉天然群体表型多样性研究   总被引:23,自引:1,他引:23  
以系统揭示云杉全分布区天然群体表型变异程度和变异规律为目的 ,以其全分布区 10个有代表性天然群体 ,每个群体 30个个体为试材 ,对针叶、球果、种鳞、种翅和种子等 17个表型性状进行系统比较分析 ,采用方差分析、多重比较、相关分析和聚类分析等统计分析方法 ,讨论了群体间和群体内的表型多样性。结果表明 :云杉种内表型性状在群体间和群体内存在极其丰富的遗传差异。云杉球果、针叶、种鳞、种翅和种子 5个表型性状的变异系数分别为 19 14 %、2 6 4 6 %、13 5 8%、19 78%和 174 0 % ,种鳞性状稳定性较其他性状高。表型分化系数 (VST)的变幅为 2 0 9%~ 4 0 6 2 % ,群体间表型分化系数均值为 30 99%。群体间变异 (30 99% )小于群体内变异 (6 9 0 1% )。 17个表型性状间多数呈极显著或显著的正相关 ,球果长度、球果径、种鳞长度、种鳞宽度和种子千粒重为云杉易测定和重要的表型性状。云杉种内群体表型变异在空间分布上呈现以纬度为主的单向变异模式 ,利用群体间欧氏距离进行UPGMA聚类分析表明 ,云杉群体可以划分为 5类  相似文献   

2.
This study represents a geographical approach to morphological variation of cones, needles and seeds in natural dragon spruce (Picea asperata Mast.) populations across western China and the relationship between morphological traits and weather variation for the origins of populations. Significant differences were found for all cone, needle and seed traits among populations and trees within populations. The coefficients of variation in 2 higher latitude populations were higher than those in other populations in all traits except for needle width and seed width. Fairly high within-population variability was also detected for cone dry weight, seed dry weight and needle traits in this study. Cone length, cone width, cone dry weight, seed scale length, seed scale width and seed wing length were strongly positively intercorrelated. Seed length and seed dry weight showed a significantly positive correlation with seed wing length. And needle width showed a significant negative correlation with cone traits, seed scale length, seed wing length and seed length. The higher the annual mean temperature, the higher the average cone length. This study also revealed a negative linear dependence on latitude: the higher the latitude, the lower the population average seed length. Seed dry weight was positively and linearly related with altitude.  相似文献   

3.
林芝云杉天然群体针叶与种实的变异及其地理趋势   总被引:3,自引:1,他引:2       下载免费PDF全文
在西藏地区11个有代表性的林芝云杉天然群体内分别随机抽取15~30个个体为试材,测量了针叶与种实共9个表型性状,采用统计分析方法研究了在群体内和群体间的变异和分化趋势.结果显示:林芝云杉9个表型性状在群体内和群体间的差异显著.群体间表型分化系数均值为29.55%,与云杉属其他树种相比处于中等水平;群体内的方差分量占70...  相似文献   

4.
祁连山青海云杉天然群体表型性状遗传多样性分析   总被引:3,自引:0,他引:3  
调查祁连山青海云杉天然分布区的10个群体,每群体10个个体 ,以系统揭示其表型变异程度和变异规律为目的,对针叶、球果、种鳞、种翅和种子的17个表型性状进行系统的比较分析.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,对群体间和群体内的表型多样性进行讨论.方差分析结果表明:各性状在群体间都存在极显著差异;除球果干质量和球果长/球果径外,其余性状在群体内都存在着极显著的差异.表型分化系数即群体间变异为31.20%,小于群体内的变异(68.80%).17个表型性状间多数呈极显著或显著的正相关.表型性状呈现出以经度变异为主的梯度规律性.通过表型性状的聚类分析可以将青海云杉10个群体划分为4个类群.  相似文献   

5.
This study represents a geographical approach to morphological variation of cones, needles and seeds in natural dragon spruce (Picea asperata Mast.) populations across western China and the relationship between morphological traits and weather variation for the origins of populations. Significant differences were found for all cone, needle and seed traits among populations and trees within populations. The coefficients of variation in 2 higher latitude populations were higher than those in other populations in all traits except for needle width and seed width. Fairly high within-population variability was also detected for cone dry weight, seed dry weight and needle traits in this study. Cone length, cone width, cone dry weight, seed scale length, seed scale width and seed wing length were strongly positively intercorrelated. Seed length and seed dry weight showed a significantly positive correlation with seed wing length. And needle width showed a significant negative correlation with cone traits, seed scale length, seed wing length and seed length. The higher the annual mean temperature, the higher the average cone length. This study also revealed a negative linear dependence on latitude: the higher the latitude, the lower the population average seed length. Seed dry weight was positively and linearly related with altitude.  相似文献   

6.
We studied seed germination and early seedling growth of Pinus densata to explore the range of variability within the species and to inform afforestation practices.Phenotypes were evaluated at a forest tree nursery under conditions that support Pinus yunnanensis, one of the presumed parental species of P. densata. Seeds were collected from 20 open-pollinated trees within each of eight autochthonous populations representing the natural distribution of P. densata in China to assess variation in germination traits and early seedling growth, and to examine the relationships among these traits. Results showed that seeds from all populations germinated and seedlings established successfully. There were significant differences among populations in 13 of 14 traits evaluated. Seed germination and early seedling growth were strongly related to seed size and seed weight. Bigger seeds germinated earlier and faster than small seeds, and seedling size was positively correlated with seed size. Some germination traits were strongly and significantly correlated with climatic variables associated with the provenance of the studied populations. Based on these observations, we conclude there were large, significant, and biologically important differences among P. densata populations in seed germination and seedling growth traits. The observed variability probably reflects a high degree of adaptive differentiation among populations that is likely to be relevant for future afforestation.  相似文献   

7.
对我国银杏全分布区200多个单株种核的主要性状进行了测定和统计。结果表明,不同气候区种核特征有一定的不同,但气候区内群体间和群体内个体间的差别更大。表明遗传改良以在遗传变异丰富的群体内开展基因型选择最有前途,但考虑到适应性,育种还应立足于本气候区群体。  相似文献   

8.
Dangasuk  O.G.  Panetsos  K.P. 《New Forests》2004,27(3):269-284
Four populations representing the entire natural distribution range of Pinus brutia (Ten.) in Crete (Greece) were sampled to determine: (1) Altitudinal variation within populations of Lassithi, Vorizia, Koustagerako, and Samaria, and; (2) Longitudinal variation among the four populations, based on morphological and anatomical differences in cone, needle and seed characteristics. Samples were collected from 10 trees per altitude, at three altitudes in each population. A total of 12 morphological and anatomical traits from needles, cones and seeds were analyzed to assess the altitudinal and longitudinal variations of the species in the island. The number of teeth per cm showed significant (P<0.01) differences between altitudes in Samaria, Vorizia and Lassithi, while needle length, width and the number of resin canals showed significant differences (P<0.01) between altitudes in Koustagerako. Cone width showed patterns of variation along the altitudinal gradient in Koustagerako, Samaria and Vorizia. Most traits had their highest means at the middle altitudes (650masl) in all the four populations. Overall, no clear altitudinal differentiation was detected, probably due to high rate of gene flow. Longitudinal variability showed a clear pattern of differentiation along the east–west climatic gradient. Needle length, width, sheath length, number of teeth per cm and the number of resin canals were the most useful traits for determining the climatic gradient clines.  相似文献   

9.
目的 探究中国沙棘和云南沙棘的遗传分化,明确二者分布区的地理边界,并评估其遗传多样性情况。 方法 利用18个简单重复序列(SSR)标记对32个中国沙棘和云南沙棘种群进行遗传变异检测,结合形态学和地理分布,利用系统发育分析和遗传结构分析鉴定种群分组情况,计算种群间遗传分化系数(FST),开展分子方差分析,计算遗传多样性参数(等位基因数(NA)、有效等位基因数(NE)、观测杂合度(HO)、期望杂合度(HE)和近交系数(FIS))。 结果 中国沙棘的遗传多样性高于云南沙棘,中国沙棘种群间的遗传分化系数低于云南沙棘。AMOVA分析显示:种群间遗传变异所占比例中国沙棘(25.5%)低于云南沙棘(36.7%),表明来自不同地理种群的中国沙棘分化程度低、遗传变异更多的来源于种群内不同个体间。系统发育树分析显示:中国沙棘个体主要聚为一大支,而云南沙棘存在多个差异较大的分支,中国沙棘和四川地区的云南沙棘关系很近。遗传结构分析将所有中国沙棘和云南沙棘个体分为2组,2亚种间邻近种群存在杂交,尤其是位于四川北部的红原、松潘种群。 结论 中国沙棘相较于云南沙棘有更高的遗传多样性和较低的种群间分化;推测2亚种的分布边界位于四川北部的红原县、松潘县地区一带。  相似文献   

10.
We studied seed germination and early seedling growth of Pinus densata to explore the range of variability within the species and to inform afforestation practices. Phenotypes were evaluated at a forest tree nursery under conditions that support Pinus yunnanensis, one of the presumed parental species of P. densata. Seeds were collected from 20 open-pollinated trees within each of eight autochthonous populations representing the natural distribution of P. densata in China to assess variation in germination traits and early seedling growth, and to examine the relationships among these traits. Results showed that seeds from all populations germinated and seedlings established successfully. There were significant differences among populations in 13 of 14 traits evaluated. Seed germination and early seedling growth were strongly related to seed size and seed weight. Bigger seeds germinated earlier and faster than small seeds, and seedling size was positively correlated with seed size. Some germination traits were strongly and significantly correlated with climatic variables associated with the provenance of the studied populations. Based on these observations, we conclude there were large, significant, and biologically important differences among P. densata populations in seed germination and seedling growth traits. The observed variability probably reflects a high degree of adaptive differentiation among populations that is likely to be relevant for future afforestation.  相似文献   

11.
This research investigated and selected 4 natural populations of Picea likiangensis in Yunnan province, based on its natural distribution. The length, width, dry weight and C, N, P contents in needles of the 4 populations were measured to survey the phenotypic variation of natural populations and the relationship between the phenotypic variation and their altitude of distribution areas. The methods of ANOVA analysis, multi-comparison and correlation analysis were used for analyzing the data measured. The results showed that, there were remarkable (P<0.01) variations in needle length, width and dry weight among populations, with component of variance 15.05%-28.03%, but no variation of them within populations. The dry weight was significantly (P<0.01) positively correlated to the needle length and width, and their correlation coefficients were 0.466 39 and 0.665 67, respectively. Regarding to element content in needles, there were significant (P<0.05) variations of N and P contents, and C/N ratio among populations, excepting C content. Moreover, the component of variance among populations was higher (29.98%-37.56%) when compared with that within populations, and there was distinctly (P<0.01) variance of N/P ratio among populations, and its component of variance was 60.44%. For correlations between needle length and N/P ratio, altitude was negatively and significantly (P<0.01) correlated; for needle width, altitude was significant (P<0.01) positive correlated, for C content and C/N ratio, altitude was significantly (P<0.05) positively correlated.  相似文献   

12.
Factors influencing levels of genetic diversity in woody plant species   总被引:91,自引:0,他引:91  
The plant allozyme literature was reviewed to: (1) compare genetic diversity in long-lived woody species with species representing other life forms, and (2) to investigate whether the levels and distribution of genetic diversity in woody species are related to life history and ecological characteristics. Data from 322 woody taxa were used to measure genetic diversity within species, and within and among populations of species. Woody species maintain more variation within species and within populations than species with other life forms but have less variation among populations. Woody species with large geographic ranges, outcrossing breeding systems, and wind or animal-ingested seed dispersal have more genetic diversity within species and populations but less variation among populations than woody species with other combinations of traits. Although life history and ecological traits explain a significant proportion (34%) of the variation among species for the genetic parameters measured, a large proportion of the interspecific variation is unexplained. The specific evolutionary history of each species must play an important role in determining the level and distribution of genetic diversity.  相似文献   

13.
We examined leaf and mature seed cone variation of Juniperus oxycedrus L. subsp. oxycedrus in 12 natural populations across the species range in the Balkan Peninsula. We measured 10 morphological traits from a minimum of 100 leaves in each of 190 individuals, and two morphological traits from 30–50 seed cones in each of 94 females. High phenotypic variation was found, but no geographical structure or cline across populations was detected for any of the studied traits. Mean values of comparable leaf and cone morphological traits did not differ considerably from values reported elsewhere. Gender dimorphism in leaf morphology was detected, but it was not distributed uniformly throughout the studied area. An ANOVA model with both nested and crossed effects revealed that the largest proportion of the total variation was, as expected, contained within populations, partly as among-tree variation (18–47%, depending on the trait) and partly as within-tree variation (33–77%), which was remarkably high. Gender dimorphism explained only 0–3% of the total variation. Differences among populations (2–23%) were significant for all studied traits except one; however, PCA showed no clear geographical differentiation of the studied populations. This lack of phylogeographical structure may be the consequence of repeatedly occurring colonisation-retreat scenarios and suggests the existence of several small refugial populations scattered over a large part of the Balkan Peninsula in the Pleistocene. Further research including palaeobotanical and molecular genetic studies will be needed to better understand the forces that shaped current variation patterns of J. oxycedrus L. subsp. oxycedrus in the Balkan Peninsula.  相似文献   

14.
濒危植物格木天然种群的表型多样性及变异   总被引:5,自引:0,他引:5  
【目的】通过对濒危植物格木在我国中心分布区种群的果荚和种子表型性状测量分析,研究其表型多样性及变异规律,结合地理气候信息探讨影响表型变异的关键因子,为格木天然种群的遗传多样性保护恢复和引种栽培提供科学依据。【方法】对8个格木天然种群114个单株的13个果荚及种子表型性状进行测量,利用巢式方差分析、多重比较、相关性分析、主成分分析、聚类分析等分析方法,探讨格木天然种群的表型多样性水平、进化和适应性潜力、表型变异规律、表型分化水平、种群聚类特征及其与地理气候因子的相关性。【结果】格木表型多样性水平中等,13个性状的Shannon-Wiener指数在1. 911 1(种形指数)~2. 103 9(果荚周长)之间,平均2. 027 8;8个种群的Shannon-Wiener指数在0. 920 9(P6)~1. 885 6(P8)之间,均值为1. 474 7。格木表型性状离散程度较轻,13个性状的变异系数在7. 544 6%(种子长)~18. 868 5%(果荚面积)之间,均值为12. 410 9%; 8个种群的变异系数在8. 852 9%(P1)~13. 984 8%(P5)之间,均值为12. 410 9%。13个表型性状的极大值为极小值的1. 395 2(种形指数)~2. 805 6(每荚种子数)倍,均值为1. 791 7。巢式方差分析表明,格木13个表型性状在种群间和种群内均存在极显著差异(P<0. 01),说明这些性状在种群间和种群内均存在丰富的变异;种群内的变异(40. 387 1%)远大于种群间(11. 948 9%)。种群平均表型分化系数为21. 857 9%,各性状的分化系数变化幅度在7. 476 5%(种形指数)~38. 674 0%(果荚宽)之间。相关性分析表明,13个表型性状之间大多存在显著或极显著相关,果荚宽度、种子周长等性状和温度指标呈负相关,与纬度呈正相关,格木在气温高、降雨量大的地区往往具有小果荚、小种子的特征,随着温度指标降低和纬度增加,格木果荚及种子有变大的趋势。格木13个表型性状可提炼为4个主成分,累积贡献率为87. 382%。8个天然群体基于欧氏距离可分为3类:第1类2个种群呈现果荚小、种子小的特征,该类表型主要出现在格木分布区的南端;第2类5个种群呈现果荚大、种子大的特征,该类表型主要出现在格木分布区的北部,仅1个种群位于分布区的南部;第3类1个种群呈现果荚小、种子少、种子大而薄的特征,该类表型出现在格木南北分布区的中间衔接部。【结论】格木的表型多样性处于中等水平,在个体上存在较为丰富的变异。在群体及物种水平上,格木表型性状离散程度较轻,各个性状分布相对集中,较为稳定,不易发生群体分化,拥有特殊表型的格木单株具有较高的保存价值。果荚及种子大小进化及适应性潜力相对较大,种形指数最不易产生变异。种群内的变异是格木表型变异的主要来源,格木的种质资源收集保存可减少种群数量,增加种群内个体数量,并优先收集有特殊表型的单株。广西省容县和龙圩区的格木种群是格木遗传多样性保护及种质资源收集保存的重点区域。年均温等温度因子是影响格木表型及分布的最主要因子。果荚及其中种子的大小是格木种群间聚类的主要依据。  相似文献   

15.
紫丁香表型多样性研究   总被引:28,自引:2,他引:28       下载免费PDF全文
以紫丁香天然林分布区抽取的4个天然群体和1个栽培群体为拟似群体,进行了其表型多样性分析.结果表明: 紫丁香表型性状存在着丰富的群体间、群体内变异,5个群体的果、种子、叶以及子代幼苗等14个表型性状差异显著,变异系数为14.25%~29.13%,表型性状分化系数为1.85%~86.67%,平均值为43.93%;群体间和群体内的差异均极显著,群体内的方差分量为56.06%,其中有10个种实性状与生态梯度值呈显著或极显著的相关,采用Dist平均分类距离系数的聚类分析得到的群体间的遗传距离关系基本上与群体采种点的生态地理位置关系一致,其中山西五老峰群体独立为一组,北部三个群体聚为一组,栽培群体聚入了北部群体组,并且与辽宁北票群体较近.依据研究结果,紫丁香种质资源收集、保护策略应当是:基于表型分化系数群体间平均值达到较高水平,而群体内保留了种质的大部分变异,所以在分布区内应首先保护天然群体的存在,即尽可能多的群体数量,同时,要很好保护天然群体的完整性.育种亲本的选择策略应当是:在群体内收集、选择特异变异的同时,加强多群体的收集和选择.  相似文献   

16.
We analyzed 17 seed sources (seed stands) of Pinus wallichiana for variations present in cone and seed characters, scattered over natural distribution in north-west Himalayan states (Uttarakhand and Himachal Pradesh) of India. The significant variations were observed in cone weight, cone length, cone width, seed length, seed width, seed weight, seed germination, radicle length, and plumule length among different seed sources of the species. Significant positive correlation between seed weight, cone weight and cone width showed that seed weight in the species depend more on the cone size. Seed germination was also positively correlated with seed weight, cone weight and radicle length in the study. The estimates of variability with regard to genetic parameters for seed weight, seed germination, cone length, cone width, cone weight showed wide range of variation in the study. Seed weight showed high heritability values coupled with maximum genetic gain. Traits with such values indicate presence of good amount of heritable additive components and are under strong genetic control. The findings of the study revealed that seed sources expressed both phenotypic and genotypic differences in the seed and cone traits which might be due to the differences in genetic make up of various seed sources and environmental factors i.e. genotypic and environmental interaction. The study suggests that the seed weight should be given the top priority for the further improvement of this species.  相似文献   

17.
《林业研究》2021,32(1)
Korean pine(Pinus koraiensis Siebold Zucc.)in Northeastern China has been genetically improved to increase seed yields in addition to timber.To assess seed yield variability and select highly productive clones,14 cone,seed and nut traits were measured and analyzed.Variance analysis showed that all clones were significantly different in various traits(P0.01).Phenotypic coefficients of variation and repeatability of traits ranged from 9.1 to34.4% and from 27.5 to 97.7%,respectively.Except for the cone layer and cone seed numbers,the other traits were positively or negatively correlated.Three principal components were identified.Seed and nut traits were the most important traits in the first principal component,and cone traits more important in the second.Using correlation and principal component analyses,cone number and other traits were selected to evaluate materials.Twenty-two clones were selected using a selection rate of 10% based on cone number independently or other combined traits.The genetic gain for different traits ranged from 6.2 to 24.3%.The selected elite clones can supply seedlings for reforestation and the selection method can provide a theoretical basis for selection in other conifer species.  相似文献   

18.
Differences in seed germination and seedling growth among populations of Pinus yunnanensis Franch.were quantified to provide information for use in the regeneration,reforestation,and improvement of this species.Seed germination and seedling growth traits at the nursery stage were investigated at the population level.We evaluated relationships between pairs of measured traits as well as the association between measured traits and geoclimatic variables including longitude,latitude,elevation,temperature and precipitation.Seedling growth showed significant differences although a low magnitude of variation was found in the seed germination traits among the populations.Some populations with strong and stable growth(e.g.,the Baoshan population) may be selected as superior seed sources for regeneration and reforestation.Germination percentage was negatively correlated with elevation,and positively with precipitation.In addition,germination index,vigor index and seedling height were positively correlated with precipitation.Seed germination index,cotyledon number and length,and seedling diameter were significantly and positively correlated with seed weight.Strong correlations between pairs of traits will be helpful in early evaluations for the selection of certain prominent traits.  相似文献   

19.
目的 为揭示山西省中国沙棘天然种群优树表型变异规律及其与生态因子的关系,为沙棘遗传资源收集、保存和品种创制提供技术支撑。 方法 以山西省中国沙棘天然种群分布区为研究对象,调查了11个中国沙棘天然种群110个优良单株的10个表型性状指标,采用方差分析和变异系数研究种群优树间的表型变异;应用相关分析揭示表型性状间及其与生态因子间的相关性;运用主成分分析和聚类分析进行了种群优树分类。 结果 中国沙棘10个表型性状在不同种群优树间呈显著(p < 0.05)或极显著(p < 0.01)差异,中国沙棘天然种群优树表型性状的平均变异系数为5.23%~37.42%。中国沙棘果实横径与果实纵径、百果质量、种子千粒质量、当年枝长均呈极显著(p < 0.01)正相关,与果形指数、结实密度呈极显著(p < 0.01)负相关;种子千粒质量与果实横径、果实纵径、百果质量呈极显著(p < 0.01)正相关;果形指数、果柄长、当年枝长与纬度因子呈极显著(p < 0.01)负相关;果实横径、果实纵径、百果质量、种子千粒质量、当年枝长与海拔因子呈极显著(p < 0.01)正相关。主成分分析结果表明:隰县种群优树的综合得分最高,五寨种群优树的综合得分最低。利用种群间欧式距离进行聚类分析,将11个中国沙棘天然种群优树分为4类,揭示了山西省中国沙棘优树表型性状未形成连续变异规律,具有随机变异的特点。 结论 山西省中国沙棘天然种群优树间存在丰富的表型变异。隰县种群优树的综合性状表现最好,可参考作为中国沙棘优良种质资源收集的重点区域。  相似文献   

20.
To achieve germplasm innovation and study genetic variation of important traits of bamboo plants,we used Bambusa multiplex,B.chungii,and Dendrocalamus latiflorus as parent materials for distant and inbred hybridizations.Two hybrid populations and three inbred populations were obtained:two populations consisted of 57 hybrid progenies from B.multiplex 9 B.chungii,26 hybrid progenies from B.multiplex 9 D.latiflorus,and three inbred progenies were from B.multiplex,B.chungii,and D.latiflorus.Traits for growth,morphology,and fiber were examined from the five populations when plants were 3 years old.Two hybrid populations had significant growth advantages in terms of height,diameter at ground level and internodal length.In terms of variability in morphological traits,the two hybrid populations followed the same trend,namely,seven morphological traits showed phenotypes that were intermediate to those of their parents;three morphological traits showed strong maternal effects,and three other morphological traits showed strong paternal effects.Among the five populations,the two hybrid populations had high arithmetic average fiber length,lengthweighted average fiber length and mass-weighted average fiber length,moreover,extensive variations of these three traits were observed within these two hybrid populations.The establishment of distant hybrid populations from these three bamboo species increased the genetic diversity more than in the other species examined.This work provides excellent materials for breeding new varieties and lays the foundation for understanding the genetics of important traits by analyzing related functional genes.  相似文献   

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