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1.
泡桐无性系数量性状的遗传分析和指数选择研究   总被引:3,自引:0,他引:3  
以10年的泡桐无性系为材料,对包括材积、胸径、树高以内的8个主要数量性状进行了遗传参数分析,并在相关分析的基础上通过指数选择法,分别对材积、胸径、树高进行了选择指数研究。结果表明:材积的遗传变异系数较大,胸径、叶基宽中等,树高、叶干重等最小。遗传力以材积、胸径、叶柄长最高,叶干重、叶面积、叶基凹入、叶基宽中等,树高最低。多性状选择指数优于单一性状。根据材积、胸径、树高的选择指数,选出了2个材积,胸  相似文献   

2.
利用田间实验和统计分析方法,研究了毛泡桐[Paulownia tomentosa(Thunb.)Steud.]与白花泡桐[P.fortunei(Seem.)Hemsl.]正反交F1无性系自然接干性状的遗传变异。结果表明,供试的11个F1无性系的22个自然接干性状具有广泛而明显的遗传变异和变异差异,其中接干高、全干高、接干材积、全干材积、接干材秽全干材积、通直度和丛枝病等级是变异最大的7个自然接干性状(CV〉30);在6个正交F1无性系间和5个反交F1无性系间,绝大多数自然接干性状的差异达极显著水平;在毛泡桐与白花泡桐正交F1无性系和反交F1无性系间,22个自然接干性状均存在极显著差异。  相似文献   

3.
为探讨马尾松改良种子园半同胞家系子代的生长变异情况,测定分析了26个家系1 年生苗高、地径和0.5年生、1.5 年生及2.5 年生幼林的树高、地径、胸径、材积和冠幅等生长指标。结果表明,各性状在家系间均存在极显著差异,参试群体的树高、胸径、材积和冠幅的家系遗传力大于0.8,且前三个性状的单株遗传力大于0.4,说明上述性状是遗传力较高的性状。2.5年生材积生长量显著高于普通生产种的优良家系有19个,入选率为73%,树高、胸径和材积的遗传增益分别为2.76%、3.60%和8.49%,与初级种子园混合种和普通生产种相比,其材积分别提高55.28%和218.28%。  相似文献   

4.
红锥家系遗传变异与优良家系选择   总被引:4,自引:0,他引:4  
为选择红锥(Castanopsis hystrix)优良家系,对2–11年生红锥家系的生长性状和遗传参数进行了研究分析。结果表明,家系间在树高、胸径和单株材积上的差异达显著或极显著水平,家系的树高、胸径和单株材积受中等或中等以上遗传控制,具有很强的家系和家系内单株选择潜力;家系的单株材积变异幅度较大,胸径居中,树高的较小,显示出红锥家系间存在着丰富的变异;家系和单株遗传力随林龄的增大逐渐变小,到7–9年生时逐渐稳定。年度生长性状的相关分析表明,树高、胸径和单株材积的遗传相关系数随林龄逐渐增大,到7年生时最大,分别达到0.9602、0.9340和0.9849,之后趋于稳定,因此,7年生可作为早期选择的适合年龄。结合早期选择及形质指标,11年生时最终选择出优良家系10个,其平均树高、胸径和单株材积分别为13.95 m、14.34 cm和0.1229 m3,平均遗传增益分别为12.24%、18.69%和51.59%,其通直度、圆满度、分枝角度、最大分枝、冠幅、枝下高等形质指标也提高7.71%~12.94%。  相似文献   

5.
为推进杉木(Cunninghamia lanceolata)育种进程,对广东乐昌市龙山林场和韶关市曲江区国有小坑林场杉木第3代育种园亲本群体的早期(3 a生)生长和结实性状进行分析.结果表明,同一育种园亲本无性系在生长性状(树高、胸径、单株材积、冠幅)和结实能力上存在显著差异,生长性状的差异甚至达到极显著水平(P<0....  相似文献   

6.
根据82年生的黄樟(Cinnamomum porrectum)树干解析数据,对江西九连山常绿阔叶林中黄樟的树高、胸径、材积的生长过程进行分析,采用有序聚类分析方法,将树高、胸径和材积划分为4个生长阶段。结果表明,10~30龄阶为树高生长速生阶段,60~80龄阶为胸径、材积速生阶段,黄樟数量成熟期较晚,可作大径材培育,并在工业原料林、混交林、乔灌复合经营以及四旁绿化中应用。  相似文献   

7.
对福建西北地区栽培的湿加松Pinus elliottii × P. caribaea 12年生林分树高与胸径生长分布进行统计分析。结果表明,林分树高分布在3~14 m范围内,胸径生长分布于2~22 cm,林分的经济生长性状呈正态分布。在同等立地条件下,湿加松早期树高生长优于乡土树种马尾松,但马尾松胸径生长6年后有更好的生长量,12年生后胸径生长相接近,马尾松12年生林分中平均木单株材积优于湿加松林分,不过11年生后开始减缓,而湿加松保持持续生长势头。由材积生长来看,各树种个体材积生长正处于快速生长期,湿加松材积生长表现出较强的生长趋势。  相似文献   

8.
长白落叶松群体遗传变异及优良家系选择的研究   总被引:2,自引:0,他引:2  
以黑龙江省林口县青山林场21年生长白落叶松(Larix olgensis Henry)异地保存林为材料,分析白刀山种源优良木和劣等木群体的生长变异情况。结果发现优势木群体和劣等木群体差异不显著。树高、胸径、材积都存在丰富的变异,其中变异系数最大的是材积,其次是胸径,最小的是树高,其变异系数分别为46.24%、19.82%和12.25%;优势木群体树高、胸径、材积的变异系数分别是12.98%、20.77%和49.36%;劣等木群体树高、胸径、材积的变异系数分别是11.47%、18.79%和43.16%。同一性状树高、胸径、材积优势木群体变异高出劣等木群体变异系数分别为1.51%、1.98%和6.2%。方差分析表明家系间差异显著,选择了856、859、563、552、567、864号6个优良家系,优良木与劣等木群体各占3个;6个家系平均值分别超过优势木群体平均值和劣等木群体平均值0.017 7和0.013 6 m3。按照各自群体10%入选率,则遗传增益分别是38.74%和30.04%。  相似文献   

9.
泡桐无性系苗期生长动态分析研究   总被引:2,自引:0,他引:2  
根据群体遗传结构模式,将毛泡桐*白花泡桐和毛泡桐*兰泡桐F1无性系的年生长进程划分为早中后期。通过用Logistic曲线对各无性系的年生长的模拟,估测了各无性系生长速率的最大点和速生期天数。根据速生期对早中后3个时期的覆程度,对不同无性系的生长形式作了分析。以正交多项式模拟生长曲线,检验了苗高,地径增长曲线的差异显著性,结果显示,无性系间苗高,地径生长曲线在阶段上存在显著差异。  相似文献   

10.
水分条件对白桦天然林生长影响的研究   总被引:1,自引:0,他引:1  
针对全球变暖导致的降水格局变化,选择生长于不同水分条件(湿生立地和中生立地)的中龄天然白桦林为研究对象,研究其生长状况并分析其生长过程。结果表明,水分条件对白桦天然林的密度和平均胸径具有显著影响(p=0.043 3和0.007 9),中生立地条件下白桦天然林的密度低于湿生立地(降低46.8%),而平均胸径则前者高于后者(增加52.4%)。中生立地白桦天然林的胸径分布为正态分布(p=0.823 9),而湿生立地白桦胸径分布呈明显的左偏(p=0.000 8)。水分条件能影响实生天然白桦胸径、树高生长过程,而对材积生长过程影响不大。湿生立地白桦的胸径速生期持续时间长于中生立地,前者速生期在6~15 a,后者在9~12 a,中生立地白桦胸径的数量成熟龄晚于湿生立地1~2 a;湿生和中生立地白桦高生长的速生期均在6 a,中生立地白桦树高的数量成熟龄晚于湿生立地3~6 a;湿生和中生立地白桦材积的速生期均在24 a以后,湿生和中生立地白桦材积的数量成熟龄均为24 a以后。  相似文献   

11.
A total of 660 individual plants ofMalva parviflora, a medicinal plant in many countries, growing in two bioclimatic regions were randomly collected with the aim of examining the differences in the allometry of this herbaceous plant growing in two bioclimatic regions. Allometric relationships were found in plant height, stem width, leaf area, leaf length, leaf width, petiole length, and leaf dry weight whereas no relationship was found between plant height or petiole length with specific leaf area. Plants growing in the cool bioclimatic region showed that plant height increases more than the increase in stem width, leaf length, leaf width, and petiole length while plants growing in the warm bioclimatic region showed that plant height increase was lower than that of stem width, leaf length, leaf width, and petiole length. Plant height relationship with root length indicated that in the cool region the plant height increase was less than the increase in the root length while the opposite occurred in the warm region. These differences can be explained by the effects of the different environmental conditions present in the two bioclimatic regions such as water scarcity and availability on the growth ofM. parviflora.  相似文献   

12.
The allometry ofUrtica urens (small nettle), an important medicinal plant in many countries, growing in an area near pollution sources and an area away from pollution sources was determined. The allometric coefficients were determined for nonlinear relationships between plant height, stem width, root length, petiole length, leaf dry weight, petiole dry weight, leaf length, leaf width, leaf area and specific leaf area. The slopes of the linear equations were determined for the above parameters. The results showed that there is a difference in the allometry of different parts ofU. urens growing in these two areas. Air pollutants reduced the plant height, stem width, root length and petiole length and increased leaf parameters. The same pattern of growth was reflected by comparing the slopes of the straight lines of the parts of the plants growing in the two areas.  相似文献   

13.
采用实验生态学的方法研究了外界支持直径变化对苦瓜植株生长和觅食行为的影响。结果表明,支持物直径变化对主茎节间、叶片、叶柄和卷须的发育进程无明显影响。苦瓜植株的攀援生长显著受到支持物直径大小的影响,当支持物直径小于8mm时,植株能较好地自主攀援生长。生长于直径支持物上的植株比生长于小直径支持物上的植株表现出较高的分枝率、较短的主茎、较长的分枝、较大的比茎长和比叶柄长。相关分析表明,节间长度和叶柄长度同植株自主攀援程度成显著正相关关系,而单叶面积、分枝数量和比叶柄长同植株自主攀援程度成显著负相关关系。作为攀援植物的一种重要资源,外界支持物的特征和存在状况将对植物的生长和行为产生重要影响。  相似文献   

14.
不同种源樟树叶片形态特征及生长差异分析   总被引:1,自引:0,他引:1  
为了解不同种源樟树叶片形态特征和生长差异,该文以30个种源樟树为研究对象,对其叶长、叶宽、叶柄长、周长、叶面积、长宽比、形态因子、株高、地径等指标进行测定和差异性分析.结果表明:(1)30个种源间叶片性状的变异系数为3.88%~16.14%,显示不同种源樟树叶片形态特征存在显著差异;叶长、叶宽、叶柄长、周长、面积、叶厚...  相似文献   

15.
The analysis of diurnal oscillatory movements of tobacco leaves was used in the diagnosis of viral infection of plants. The oscillatory helices circumscribed by a growing leaf of a healthy plant were regular, but some deviations, particularly in the transition points, were recorded. In order to make clear the cause of these irregularities of trajectory, the course of elongation of leaf petiole and blade in relation to localization and shift of zones of elongation during ontogenesis was analysed. The present analysis is similar to that described by the author's earlier experiments with pea roots. Oscillatory curves circumscribed by petiole, projected on a horizontal plane, were compared with curves circumscribed by the blade tip. The analysis of the leaves of different ages enabled us to study this process in dependence on growth rate. It was confirmed that oscillations are a result of elongation; the extent of oscillations is quantitatively dependent on the growth rate. An analysis of the zones of growth showed that in petiole the active meristems are localized near to its base while in the leaf lamina they move gradually during the ontogenesis from the apical to the basal part of the leaf blade. Active meristems of young rapidly growing leaves are localized approximately in the middle of the blade while those of old leaves were found in close proximity to the base of the lamina. The growth rate of petiole can be expressed in hundreds of mm per hour (4.8×10?2 mm h?1); half of this value was recorded for its apical part. The growth rate of leaf blade was found approximately ten times higher (3.2×10?1 mm h?1). The oscillatory movements of growing leaf consists of two integrate components: of oscillations originating in the base of the petiole and of oscillations of leaf blade the centrum of which is localized in the basal third of the blade. The arrangement of the experiments did not enable us to determine to what extent the phototropic response of leaf blade participates in leaf movements. The movements of leaves of an intact plant are evidently affected by rhythmic stem oscillations. Stem is an integral part of a system which participates in the transfer of information in plants.  相似文献   

16.
为挖掘辣木(Moranga oleifera)优良种质资源,对30个优良单株家系的叶片表型性状进行研究。结果表明,除叶形外,辣木不同家系间的叶柄和叶片颜色、复叶数、复叶柄长度和直径、复叶间距、叶长、叶宽均存在不同程度的差异。复叶数与复叶柄长度和直径、复叶间距、叶长、叶宽呈极显著正相关;主成分分析表明,叶长、叶宽、复叶柄长度和直径、复叶间距、叶柄和叶片颜色是区分辣木不同家系最主要的叶片性状指标。聚类分析结果表明,30个辣木家系可分为3大类,叶片表型性状存在显著差异的家系的遗传距离较远。因此,叶柄和叶片颜色、复叶数、复叶柄长度和直径、复叶间距、叶长、叶宽将为直观区分辣木家系提供参考。  相似文献   

17.
半干旱黄土丘陵区人工林叶面积特征   总被引:6,自引:0,他引:6       下载免费PDF全文
 该文通过对黄土丘陵区4个密度的刺槐(Robinia pseudoacacia)人工林、3个密度的侧柏(Platycladus orientalis)人工林生长季叶面积变化的研究,揭示了不同密度林分叶面积生长与林分密度的关系;通过对灌木生长季叶面积变化的研究,建立了灌木柠条(Caragana korshinskii)、沙棘(Hippophae rhamnoides)和紫穗槐(Amorpha fruticosa)叶面积与叶鲜重、枝条基径的经验公式,为半干旱区灌木生长调查提供了一种方便、快捷的方法。结果表明:1)刺槐和侧柏各密度林分的单株林木叶面积和叶面积指数均在9月达到最大值,其中刺槐林叶面积指数峰值可达到10.5,侧柏峰值可达到3.2;灌木柠条、沙棘和紫穗槐叶面积和叶面积指数都在8月份达到各自的最大值,柠条、沙棘和紫穗槐的叶面积指数峰值分别为1.1 95、1.123和1.882;2)刺槐叶面积与叶鲜重具有极显著相关的幂函数关系,侧柏、柠条、沙棘、紫穗槐叶面积与叶鲜重具有极显著相关的线性函数关系,其中柠条枝条基径与叶面积还具有极显著相关的幂函数关系,沙棘、紫穗槐枝条基径与叶面积还具有极显著相关的线性函数关系;3)黄土丘陵区,由于林地土壤水分条件的限制,承载力有限。人工林进入生长盛期后, 不同密度刺槐和侧柏林分叶面积指数趋于一致,与最初的造林密度和现存密度没有关系。在不同密度的刺槐和侧柏林分间,单株叶面积与其林分密度成反比。在对上述结果分析的基础上得出:黄土丘陵区,由于林地土壤水分条件的限制,承载力有限。该文所研究的刺槐和侧柏各林分均已达到了当地土地承载力的上限,基于提高单株林木质量的考虑,建议刺槐林郁闭后的密度不超过833株&;#8226;hm-2,侧柏则不超过1 111株&;#8226;hm-2。如以全林分生物量为目标,林分密度也可适当减小。  相似文献   

18.
Scaphium macropodum (Miq.) Beumee ex Heyne (Sterculiaceae) in a tropical rain forest in West Kalimantan (Indonesia) was analyzed from the viewpoint of statics. The petiole diameter must increase with increasing leaf size to retain enough mechanical stability and a sufficient amount of conductive vessels. The petiole's cross-sectional area at its base was found to be proportional to the leaf blade's dry mass, which indicates that Shinozaki's pipe model is applicable to leaves with different sizes. Although larger leaves produce greater bending moments on the petiole's cross-section as a result of their greater weights, the bending stresses at the petiole's base caused by the leaf's weight were constant at ca. 76,900 g cm−2 regardless of leaf size. Thicker petioles increase the leaf's mechanical stability, but require sizable energy investments for their construction. It is hypothesized that the constant value for petiolar stress indicates an optimal balance between energy economy and the mechanical stability of S. macropodum leaves. To keep bending stress constant, the leaf blade's center of gravity shifts to a more proximal position and the cross-sectional area of the petiole increases. Received 8 December 1997/ Accepted in revised form 1 December 1998  相似文献   

19.
光照条件对蒙古栎幼苗生长及形态特征的影响   总被引:5,自引:0,他引:5  
对生长于不同光照环境(林内和林外)下的蒙古栎幼苗的形态特征进行了比较.结果表明,光照条件对蒙古栎幼苗的生物量及其分配具有明显影响,林外幼苗单株生物量为林外的4.48倍,其中以根系生物量的差别为最大,林外为林内的6.23倍;林外与林内幼苗根冠比分别为2.70和1.11.在不同的光照条件下,蒙古栎幼苗的叶片形态表现出明显不同,林外叶片比叶面积明显低于林内,分别为139.55cm2/g 和284.94cm2/g,林内约为林外的2.04倍;一次生长叶面积林外明显低于林内,总叶面积则高于林内.二次生长使蒙古栎幼苗的叶面积有明显增加,但是经过二次生长后,幼苗的单株生物量没有明显增加,说明二次生长叶片对于蒙古栎幼苗生物量的积累没有明显贡献;光照对于蒙古栎主干及根系的形态具有明显影响,林外幼苗高(包括二次生长)明显低于林内幼苗,而地径则相反,林外幼苗根系的长度和直径则明显高于林内幼苗;林外幼苗顶芽体积明显大于林内幼苗.同时,林外幼苗的二次生长导致顶芽体积明显下降,从而对翌年的高生长量和未来干型产生影响.认为,蒙古栎幼苗通过形态上的一系列可塑性变化来适应不同的光环境以获取最大的碳收益.  相似文献   

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