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1.
运用杉木种源,林分,家系三水平联合试验6年生林分的生长性状和物候观测资料,研究其遗传变异信息,结果显示,种源间,种源内林分间,林分内单株间的胸径,树高,材积都存在极显著差异,在三水平任何层次上的生长性状选择都是有效的,但各层次变异差别很大,其方差分量排序依次为,种源〉林分〉家系,种源,林分,单株材积遗传力分别为0.848,0.399,0.232;选择层次依次是种源,林分,单株,种源(群体)的较稳定  相似文献   

2.
杉木种源-林分-家系遗传变异研究   总被引:3,自引:1,他引:3  
运用杉木种源、林分、家系三水平联合试验6年生林分的生长性状和物候观测资料,研究其遗传变异信息。结果显示,种源间、种源内林分间、林分内单株间的胸径、树高、材积都存在极显著差异;在三水平任何层次上的生长性状选择都是有效的,但各层次变异差别很大,其方差分量排序依次为:种源>林分>家系,种源、林分、单株材积遗传力分别为0.848、0.399、0.232;选择层次依次是种源、林分、单株。种源(群体)是较稳定的遗传单位,但种源内林分间差异显著,可进一步探讨遗传学上的杉木种源单位的确切范围。种子发芽率、物候因子分析表明,种源间差异显著,林分间差异不显著。  相似文献   

3.
本文对福建省官庄林场杉木第二代种子园自由授粉子代试验林树高、胸径和材积等生长性状进行了研究。子代测定结果表明,参试家系间的效应显著;利用方差分析的结果,估算了杉木树高、胸径和材积的家系遗传力和单株遗传力,并以10%、20%的选择强度估算出杉木的遗传增益值。通过分析得出杉木各生长性状间有较高的相关性。依材积选择出46个优良家系,用作造林,4年生时估计其遗传增益可达41.37%~51.37%。  相似文献   

4.
杉木无性系的遗传变异及优良无性系选择   总被引:9,自引:0,他引:9  
试验揭示了杉木无性系在树高、胸径、单株材积和开花结果等方面有巨大的遗传差异。从99个参试无性系中选出了6个优良无性系,与种子园实生苗相比较,树高增益19%-26%,胸径增益17%-34%,单株材积增益50%-114%。分析了杉木家系选择和无性系选择的遗传改良潜力。无性系树高、胸径和单株材积的遗传变异系数分别是家系遗传变异系数的2.6倍、3.1倍和3.1倍。在入选率相同的条件下,无性系树高、胸径和单株材积的选择响应分别是家系选择响应的2.8倍、3.6倍和3.5倍。  相似文献   

5.
对营造在浙江省龙泉市林科院6年生杉木三代种子园家系(36个家系,1个对照)子代林的树高、胸径和材积进行测定与分析.结果表明:6年生杉木的树高、胸径和材积3个生长性状在家系间差异达极显著,且有相对较高的广义遗传力,而材积有中等以上的遗传变异系数.杉木三代种子园有较好的群体改良效果,6年生时材积的遗传增益比对照提高了14.89%.以材积为依据,采用对比法选择出9个早期速生型杉木优良家系,其群体的树高、胸径和材积平均值分别大于对照10.04%、15.99%和45.69%.  相似文献   

6.
本文对福建省官庄林场杉木第二代种子园自由授粉子代试验林树高,胸径和材积等生长性状进行了研究。子代测定结果表明。参试家系间的效应显著;利用方差分析的结果,估处了杉木树高、胸径和材积的家系遗传力和单株遗传力。并以10%、20%的选择强度估算出杉木的遗传增值。通过得出杉木各生状间有较高的相关性。依材同46个优良家系,用作造林,4年生时估计其遗传增益可达41.37-51.37%。  相似文献   

7.
杉木第二代种子园自由授粉子代测定效果分析   总被引:3,自引:0,他引:3  
对洋口林场杉木第二代种子园自由授粉子代试验林树高、胸径和材积等生长性状研究结果表明 :杉木第二代种子园子代生长在家系间存在着显著差异 ,家系内个体间的遗传分化剧烈。从群体中选出的优良家系及家系内优良的单株造林 ,增产效果显著 ;杉木在树高、胸径和材积等生长性状间有较高的表型和遗传相关性。  相似文献   

8.
杉木杂交亲本分子遗传变异与子代生长相关的研究   总被引:17,自引:0,他引:17       下载免费PDF全文
以30个杉木杂交亲本的RAPD分析为基础,对亲本间分子遗传变异与子代树高、胸径和材积及其变异系数和亲本间各性状的特殊配合力的相关关系进行了研究。结果表明,亲本间遗传距离只与胸径特殊配合力和材积特殊配合力在0.10显著性水平上呈负相关,而与其它因子相关不显著。分别对亲本聚类分析的组内和不同组间的亲本间遗传距离与各因子进行相关分析,组内亲本间遗传距离与各因子的相关基本不显著;在中等平均遗传距离上,组间亲本间遗传距离与子代树高、胸径和/或材积性状达0.05显著水平的相关,但与各性状的变异系数和亲本间特殊配合力相关不显著。共检测到23个标记位点显著影响材积性状(α≤0.10)。根据亲本携带的材积显著性位点对各家系进行赋值,家系的显著性位点值与胸径和材积两性状及其变异系数达0.01显著水平的相关,但与树高性状和其它各因子相关不显著。结论认为,杉木亲本的分子遗传变异与子代生长的相关关系较为复杂;亲本的分子遗传变异对亲本选配有一定的参考价值;材积显著性位点对分子标记辅助的亲本选配和子代表现预测有较大的应用潜力。  相似文献   

9.
杉木无性系生长和木材密度的遗传变异及选择   总被引:3,自引:0,他引:3  
研究了8年生杉木无性系试验林的树高、胸径、材积和木材密度的遗传变异规律。结果表明:试验中各性状在无性系间存在显著差异,遗传变异系数树高为9.0%,胸径为13.7%,材积为30.0%,而木材密度只有6.7%,各性状均有较高的重复力,木材密度和胸径的重复力在90.0%以上。树高、胸径、材积3个生长性状间有较高的遗传正相关,而胸径、材 与木材密度间表现出中度的遗传负相关,树高与木材密度间则表现出弱度的遗  相似文献   

10.
对8年生巨桉种源、家系试验林进行全面调查分析表明:生长性状在不同种源、家系间存在显著或极显著差异;形质性状在不同种源间差异不显著,在不同家系间存在极显著差异;耐寒能力在不同种源间存在极显著差异,在不同家系间差并不显著。通过综合评价和比较,选出适应福建省永安地区种植的巨按优良家系10个,树高、胸径、材积和耐寒指数平均值分别为14.80m、16.6om、0.1749m^3和4.42,树高、胸径和材积的遗传增益分别为18.96%、加.44%、67.17%;优良个体15株,其树高、胸径、材积和耐寒指数平均值分别为17.91m、20.63cm、0.2976m^3和4.85,树高、胸径和材积的遗传增益分别为44.9%、48.8%和184.1%。这些优良材料可以通过无性繁殖进行推广应用。  相似文献   

11.
油松自由授粉家系分阶段测定与选择的差异分析   总被引:1,自引:1,他引:1       下载免费PDF全文
为了分阶段测定油松自由授粉家系间差异和选择油松优良家系,对82个油松家系(22年生)进行生长性状的遗传变异分析,分析树高和胸径的年-年遗传相关、表型相关及历年的遗传方差和环境方差、遗传及表型变异系数、遗传力的同时,研究不同林龄树高和胸径与22年生时材积的相关关系。结果表明:油松家系间树高、材积等生长存在极显著差异。结合早期选择效率和选择正确率及去劣错误率,认为油松优良家系选择是可以在早期进行的,其初选年龄应是9年生时。此外,在22年生时以材积育种值为选择指标,筛选出24个油松优良家系,其单株材积实际增益分别较对照28、95和106增加了36.54%、8.92%和18.63%。最终选出速生优良家系和二代优树 61株,子代测定林入选二代优树的材积遗传增益分别较对照28、95和106增加了57.74%、25.81%和37.03%。所选出的优良家系和优良单株可作为油松育种材料在生产上推广应用。  相似文献   

12.
Different methodological approaches from the field of spatial statistics, the index of cluster size (ICS) and quadrat methods such as the two-term and three-term local quadrat variance (TTLQV and 3TLQV) and the new local variance (NLV) were tested to find a simple spatial measure to classify mixed coniferous uneven-aged, even-aged and conversion stands in the central Black Forest area of Germany. Altogether six stands were analysed with regularly distributed sample plots of 0.25 ha (50×50 m), each subdivided into 25 quadrats of 10×10 m. In each of the quadrats, diameter at breast height (dbh) for trees of the overstory (dbh>7 cm) was assessed and classified into three diameter classes. Height measurements were used to develop specific stand height curves for each stand and to calculate the standing volume per tree and per quadrat. The even-aged stands showed a regular distribution of the standing volume, while the conversion and uneven-aged stands were more clustered. This was detected using ICS, which proved to be a simple but very efficient measure for stand structure. The ICS also showed a highly random distribution of small and medium trees and a regular distribution of large trees of the overstory in the uneven-aged stand. Large and medium trees of one even-aged stand were also regularly distributed while conversion stands showed a regular, random or slightly clustered distribution of these trees. The more uneven the ages in the stands were, the larger were the phases detected by the NLV. The findings of the ICS were generally supported by the TTLQV and 3TLQV. The more uneven the ages in a stand were, the less clustered were the trees of different sizes of the understory. Clustering also decreased with increasing height of understory trees. The patterns detected in the investigated stands were related to the effect of different management regimes. Implications for the management of conversions stands based on the findings of the study are given.  相似文献   

13.
Maritime pine (Pinus pinaster Ait.) seedlings from four stands of central Italy were inoculated with a suspension of 75,000 basidiospores/ml. Significant differences among the stands were found for the following traits: percentages between nonspotted and inoculated seedlings; and percentages between seedlings with spermagonia of Cronartium flaccidum and spotted seedlings. Genetic variation in blister rust resistance among the stands and among the families within a stand confirms the validity of the idea to select the stands which are exposed to heavy rust infection and then within the selected stands to choose trees able to supply the highest possible number of nonspotted seedlings and seedlings with needle spots but without spermagonia.  相似文献   

14.
日本落叶松家系对树高生长模型参数的影响   总被引:2,自引:1,他引:1  
以湖北省建始县长岭岗林场 15年生日本落叶松子代测定林为研究对象 ,研究了家系间优势高的生长变异 ,家系对树高生长模型参数影响的显著性检验 ,并构建了日本落叶松家系树高生长模型。研究表明 ,同一立地不同家系的树高—年龄关系为多形曲线 ,不仅渐近线存在显著差异 ,而且曲线的形状也发生改变 ,应采用不同的生长模式来描述其树高生长过程 ,优势高生长是环境差异和遗传变异的树木表现型的综合反映 ,树高生长潜力 (立地指数 )随着遗传改良材料的应用而增大 :Schumacher和Richards方程对模拟日本落叶松幼龄阶段不同家系的优势高生长过程均能达到令人满意的效果 :家系间优势高的差距随年龄而增大 ,且家系间连年生长速率也各不相同。  相似文献   

15.
1989年至1996年间,台山红岭种子园从美国、澳大利亚、津巴布韦引入湿地松基因资源种子共407份,包括有6个种源、213个全同胞家系和188个半同胞家系。利用其中370份材料营建种源林1片、基因资源林6片,面积共16.85hm^2。根据这7片测定林的调查数据分析了新引材料的遗传品质以及选择潜力,造林保存率平均达90%以上;在生长量方面,有66.67%的种源、82.14%的家系优于台山湿地松初级种  相似文献   

16.
杉木林分密度效应研究   总被引:20,自引:3,他引:20       下载免费PDF全文
该项试验共分2个部分.(1)造林密度试验,小区面积为600 m2,5个处理,即1 667株.hm-2(A)、3 333株.hm-2(B)、4~983株.hm-2(C)、6 633株.hm-2(D)、9967株.hm-2(E);(2)造林密度调控试验,造林设计方法与造林密度试验相同,但在林分生长过程中,按密度管理图的密管线0.5为标准进行间伐,间伐后保留密度要与临近的下一个初植密度较稀植的林分密度基本相同,两者进行比较.试验结果(1)造林密度试验,优势高、平均高、平均胸径均随年龄的增加而递增,随密度的增加而递减,优势高9a、平均高6 a、平均胸径5 a,密度间差异已达显著性水平;林分蓄积量则随年龄增加而递增,5~7 a,密度间差异显著,8~18a,只有A密度与E、D密度差异显著;枝下高随密度、年龄的增加而递增,12~a后,C、D、E密度间的差异很小;冠幅随密度的增加而递减,随年龄的增加而递增,9~10a后,各密度则随年龄增加而缓慢递减.(2)造林密度调控试验,同一指数级,间伐后的林分与其密度基本相同未间伐的林分比较,其优势高、平均高差异不明显;立木蓄积前者小于后者;总蓄积(立木蓄积+间伐蓄积)前者大于后者;同一指数级,初植密度不同的林分,间伐后与密度基本相同未间伐林分的蓄积百分比,初植密度大的大于初植密度小的;指数级不同,而初植密度相同的林分,间伐后与密度基本相同未间伐的林分总蓄积百分比,高指数级的比值大于低指数级的比值.  相似文献   

17.
The increasing commercial interest and advancing exploitation of new remote territories of the boreal forest require deeper knowledge of the productivity of these ecosystems. Canadian boreal forests are commonly assumed to be evenly aged, but recent studies show that frequent small-scale disturbances can lead to uneven-aged class distributions. However, how age distribution affects tree growth and stand productivity at high latitudes remains an unanswered question. Dynamics of tree growth in even- and uneven-aged stands at the limit of the closed black spruce (Picea mariana) forest in Quebec (Canada) were assessed on 18 plots with ages ranging from 77 to 340 years. Height, diameter and age of all trees were measured. Stem analysis was performed on the 10 dominant trees of each plot by measuring tree-ring widths on discs collected each meter from the stem, and the growth dynamics in height, diameter and volume were estimated according to tree age. Although growth followed a sigmoid pattern with similar shapes and asymptotes in even- and uneven-aged stands, trees in the latter showed curves more flattened and with increases delayed in time. Growth rates in even-aged plots were at least twice those of uneven-aged plots. The vigorous growth rates occurred earlier in trees of even-aged plots with a culmination of the mean annual increment in height, diameter and volume estimated at 40–80 years, 90–110 years earlier than in uneven-aged plots. Stand volume ranged between 30 and 238 m3 ha−1 with 75% of stands showing values lower than 120 m3 ha−1 and higher volumes occurring at greater dominant heights and stand densities. Results demonstrated the different growth dynamics of black spruce in single- and multi-cohort stands and suggested the need for information on the stand structure when estimating the effective or potential growth performance for forest management of this species.  相似文献   

18.
Density management is the usual method used by silviculturiststo achieve a desired future stand condition, and one of themost effective methods of design, display and evaluation ofalternative density management regimes in even-aged stands isthe use of stand density management diagrams. In the presentstudy, we describe a method for developing thinning schedulesfor even-aged pedunculate oak (Quercus robur L.) stands in Galicia(north-western Spain), using a density management diagram. Thediagram integrates the relationships among stand density, dominantheight, quadratic mean diameter and stand volume in a singlegraph. The data used in its construction were obtained from172 sample plots located throughout Galicia. The diagram isbasically composed of two equations: the first relates the quadraticmean diameter to the stand density and dominant height; thesecond relates the stand volume to the quadratic mean diameter,stand density and dominant height. These equations were fittedsimultaneously using full information maximum likelihood. Therelative spacing index is used to characterize the growing stockand the diagram provides isolines for dominant height, numberof trees per hectare, quadratic mean diameter and stand volume.Dominant height isolines together with the site index curvesallow specification of the timing of thinnings while intermediateand final harvest volumes are calculated using the stand volumesisolines.  相似文献   

19.
以7个种源的194个尾叶桉家系试验林为材料,初选尾叶桉优树48株,优势木240株。综合评定尾叶桉选优标准为胸径、树高、材积分别超过5株优势木均值的10%、13%、17%,超过林分平均木均值的13%、16%、25%;确定干形、分枝均匀度为优树选择时需要考虑的2个主要形质指标。  相似文献   

20.
基于广东省59 块针阔混交异龄林一类固定样地实测数据,采用7 种方法计算林分优势高,对7 种计算方法获取的林分优势高进行相关性分析和差异分析,并建立了林分优势高和林分平均高的线性模型。结果表明,针阔混交异龄林的7 种林分优势高间的相关系数均超过0.9;根据差异性分析结果和调查、计算简单的原则,确定不分树种取最大3 株优势高的算术平均作为针阔混交异龄林的林分优势高;林分优势高与林分平均高之间的关系方程为Y= 0.948 9X+4.133 7, 决定系数R2 为0.656 3,具有良好的线性关系。  相似文献   

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