不同降雨型桉树种苗期特性研究

以新引入四川的20个桉树品种71个种批号种子为材料,开展了育苗试验及苗期生长发育特性观察,重点观察了分别代表冬雨、夏雨、均匀降雨型的品种王桉、大花序桉、白腊树桉的苗期特性。结果表明:不同品种种子萌芽所需的温度、湿度是不一致的,在相同的温湿度条件下,各个品种发芽期、发芽率不同,但苗期发育特性基本相同。苗木的个体发育前期是根的快速生长,苗木高、地径、根的生长量随叶片数量增加而增加;夏季播种的夏雨型品种和部分均匀降雨型品种出苗整齐,出苗率一般在85%左右;冬雨型品种发芽极不整齐,发芽期从8月延续到翌年3月。同一品种秋季和初夏育苗的效果也不一致。     

Growth and phenology of seedlings of four contrasting slash pine families in ten nitrogen regimes

Seedlings of two fast- and two slow-growing families of slash pine, Pinus elliottii Englm. var. elliottii, were grown in a greenhouse for one growing season in one of 10 nitrogen (N) regimes. Increasing the N concentration in the nutrient solution resulted in both increased growth rates during the exponential growth phase and extended duration of the growing season. The two components of total height, free growth (epicotyl length to the first bud) and summer growth (height growth after the first bud), both increased significantly with increasing N concentrations up to 40-60 mg l(-1) but decreased at N concentrations above 180 mg l(-1). Compared to seedlings grown in the presence of an optimum N concentration, seedlings grown in the presence of trace amounts of N were smaller and had less summer growth as a percentage of total growth, earlier cessation of height growth, fewer flushes, lower shoot/root ratio, higher root fibrosity, and lower N concentrations in all seedling tissues. Compared to slow-growing families, fast-growing families had more summer height growth, more flushes and later growth cessation, higher shoot/root ratios and higher root fibrosity at all N concentrations. In the presence of an optimum or higher concentration of N, the fast-growing families also had higher needle and total N concentrations than the slow-growing families. Strong family by N-treatment interactions occurred for height, phenology and biomass traits because of the extra responsiveness of one family to increasing N concentration. Several seedling traits were identified that appear promising for predicting field performance in slash pine. The results indicated that the nutrient environment greatly influences genetic expression (e.g., family patterns of summer growth were most closely related to field rankings for seedlings in the trace-N treatment).     

欧洲白桦早期生长性状表现与优良家系选择

在测定分析欧洲白桦13个家系子代生长节律、适应性及早期性状表现的基础上,系统研究生长性状变异规律,并结合优树、子代测定林和子代苗期的生长表现,进一步开展优良家系选择。结果表明：各家系子代生长高峰期均集中在7月上旬至8月初,树高和地径性状均呈正态分布,且家系间和家系内差异显著,家系间抗寒适应性差异较小。综合评价各项指标,筛选出5个生长稳定、遗传分化较小的优良家系,即：6#、9#、1#、10#及13#家系。     

The effects of test environments on estimation of genetic parameters for seedling traits in 2‐year‐old Douglas‐fir

The effects of test environments (dry versus wet) on estimation of genetic parameters in seedling traits were studied in 160 open‐pollinated families of Douglas‐fir (Pseudotsuga menziesii (Mirb.) Franco) from southwestern Oregon. Seedlings from four populations were grown in two test environments for two growing seasons. Between test environments, ‐9 bars of water potential difference were created in both growing seasons. Estimated genetic variances in most growth and phenology traits were considerably higher for seedlings grown in the wet environment than for those in the dry. Estimated genetic correlations between the same traits measured in different test environments indicated that most seedling traits studied for two growing seasons are genetically stable in both environments—i.e., suggesting that genotype by environment interaction in these traits are weak. However, the effect of test environment on estimation of genetic parameters in seedling traits, especially in adaptive seedling traits, should be evaluated very carefully when early evaluation of genetic entries is practiced in Douglas‐fir since these traits (budburst timing, lammas growth and free growth) appear to be plastic traits.     

Variation in seed traits and seedling vigour of <Emphasis Type="Italic">Cordia africana</Emphasis> Lam. provenances in Ethiopia

Cordia africana is a very important indigenous tree species for timber and other products and services in Ethiopia. Seed traits and seedling vigour of seeds from 12 provenances of the species were compared. Mean seed mass for each provenance was assessed for 1000 seeds in 10 replications, and seed length and width were measured for 100 seeds in four replications per provenance. Germination was assessed in a glasshouse taking 400 seeds from each provenance. Root collar diameter and height of 440 seedlings grown in a nursery for 290 days in Addis Ababa were measured. Seed length, seed width, seed mass, and shoot height and root collar diameter of seedlings showed significant differences (P < 0.001) among provenances. Correlation analysis between seed and seedling traits and environmental variables revealed significant positive correlations between seed width and germination percentage, seed width and altitude, seed width and longitude and seed length and latitude. Negative correlations were obtained between seed width and temperature, seed width and rainfall, seed mass and temperature, and germination and temperature of the seed source. As expected, differences in seed trait did not explain the variability in seedling vigour. Determining quantitative variations in seed traits and seedling vigour among provenances and the patterns along environmental gradients are essential for informing decisions on the tree improvement programme of the species.     

民勤干旱荒漠区唐古特白刺夏季容器育苗技术

探讨了民勤干旱荒漠区唐古特白刺夏季容器播种育苗技术,包括种子催芽、营养土配制、苗床设置、营养钵播种方式和苗期管理等。唐古特白刺夏季容器播种苗当年平均苗高15.7cm,平均地径0.38cm,其生长呈S形曲线,8月份苗高和地径生长较缓慢,9月份生长迅速,10月份生长缓慢并开始木质化直至停止生长。唐古特白刺夏季容器育苗可当年冬季或次年春季出圃造林。     

马尾松实生种子园五年生的植株生长与分枝

本文研究了马尾松实生种子园建立第五年时植株的生长与分枝状况,研究的性状包括树高、胸径、枝条总数、年高生长、 年枝条生长量、年分枝数、不同分枝处树干直径等。对总的生长与分枝性状(含树高、胸径、枝条总数)分析表明:家系间只在胸径方面存在显著差异。对分年度的生长与分枝性状的研究表明:家系间在年高生长、年枝条生长量、年枝条直径方面无显著差异;年分枝数在刚建立的前两年家系间没有显著差异,后两年则差异显著;不同分枝处树干直径在连续的四年内,家系间均存在显著差异。不同年度的生长与分枝的趋势分析结果发现,大部分家系的年高生长与年枝条生长呈递增型,而大部分家系每年的分枝数却为波动型。这些研究结果表明,该马尾松实生种子园到建立的第五年时,家系间的差异大部分都不显著。究其原因,一方面可能是马尾松初期生长节律;另一方面可能是因为建园家系复杂的父本构成。因此,这个时期进行家系选择不太有效,建议在利用优树自由授粉子代建立实生种子园时,对他们先期进行苗期选择,而不是采用所有的子代。图1表4参20。     

杉木遗传变异组成试析

70年代以来,我国杉木遗传改良工作已发生了根本性的变化,不仅在生态造林区已相继选育出了一批速生型的优良家系、优良种源和优良无性系,而且还不同程度地在生产中得到了推广应用,取得了显著的经济效益。近年来,有关杉木多世代育种的探讨已有不少报道,但立论于遗传变异基础上,纵贯从群体到个体,综合多性状变异相关的见解却不多见,其主要原因或许是有意识地设置这方面的试验还显得不足之故。为此,我们在承担全国杉木协作     

Inter- and intra-provenances variations in seed size and seedling characteristics of Khaya senegalensis A. Juss in Burkina Faso

Within- and between-provenance variations in seed and seedling traits of Khaya senegalensis A. Juss were studied at INERA in Burkina Faso. Nursery grown seedlings from four provenances in Burkina Faso were used for the study. The studies revealed significant variability in all traits evaluated. Seed length and weight significantly varied among provenances and families within provenances, where Bopiel and Koyenga had the highest mean values. Height and root collar diameter of 1 year old seedlings significantly varied among families within provenances. Except leaf biomass ratio and carbon isotope ratio which varied significantly among provenances but not among families within provenances, all other seedling biomass traits—total plant biomass, stem biomass ratio, leaf biomass ratio, root biomass ratio, root shoot ratio, specific leaf area, and leaf area ratio were significantly affected by provenances and families within provenances. The magnitude of variation due to family effect ranged from 65 to 93 % for seed size traits, and from 4.5 to 17.8 % for seedling characters. Estimates of family heritability were moderate to high (0.67–0.95) for seed traits, but low to moderate (0.19–0.59) for seedling characters, indicating that much of the total variation in seed traits is due to the genetic effect. The two most prominent provenances, Koyenga and Bopiel, with higher seed size and greater seedling growth could be considered for an eventual K. senegalensis improvement program in Burkina Faso.     

Provenance Variation in Seed Morphometric Traits, Germination, and Seedling Growth of Cordia africana Lam

Patterns of genetic variation in Cordia africana, a tropical timber species, were evaluated at the population level. Bulk seed samples were collected from six natural populations in Ethiopia and examined for variations in seed morphometric traits, seed germination, and seedling growth at nursery stage. Analysis of variance revealed significant differences among provenances in all studied attributes except root collar diameter after 4 months of growth. The provenance effect, as determined by broad sense heritability, was 71–98% for seed morphometric traits, 80% for germination capacity, 42% for germination energy, 57–58% for seedling height and 3–13% for root collar diameter. Seed weight showed a significant positive correlation with altitude and negative correlation with mean annual temperature of seed origin. Germination energy was significantly correlated with longitude and mean annual rainfall. Seedling parameters and geo-climatic variables of seed origin were fairly correlated. A significant intercharacter correlation was found between seed length and seed weight, between root collar diameter at the age of 4 months and seed length and weight, as well as between seedling height after 4 and 8 months of growth. It can be concluded that the observed patterns of variation will have implications for genetic resources conservation and tree improvement.     

Development of canopy stratification during early succession in northern hardwoods

Canopy development on a 6-year-old strip cut was analyzed by measuring the heights to terminal buds and bud scale scars of the tallest individuals of each species present on 50 plots of radius 6 m. Phenology of height growth was monitored during the following growing season. Pin cherry (Prunus pensylvania L.), an intolerant short-lived tree, had the fastest growth rate and was on the average the tallest species from the second to the sixth year of regrowth. Although advance regeneration of sugar maple (Acer saccharum Marsh.) and beech (Fagus grandifoloa Ehrh.) were the tallest trees during the first growing season, their slower growth rate insured that they would not keep up with the pin cherry. Trembling aspen (Populus tremuloides Michx.), striped maple (Acer pensylvanicum L.) and yellow birch (Betula alleghaniensis Britt.) occupied an intermediate position in the canopy by the end of the sixth growing season, and showed relatively greater annual height increment than beech or sugar maple. Height growth phenology differed slightly for each species. Beech, ash (Fraxinus americana L.) and sugar maple commenced growth early, grew rapidly and set buds all by 1 August (beech by 15 June). Yellow birch, pin cherry and trembling aspen started growing as early as the others, grew more slowly at first but then grew for a longer period of time. Striped maple seemed to be somewhat intermediate. Growth phenology and growth rate are related to the tolerance and growth form type (e.g. determinate or indeterminate) of the species. The most tolerant species tend to be determinate in growth form, have slower growth rates and complete height growth earlier. The intolerant species tend to be indeterminate, have a faster growth rate and continue to grow for a longer period. These may be mechanisms by which many species can grow together and avoid adverse effects such as suppression.     

油松自由授粉家系分阶段测定与选择的差异分析

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。     

Variation in seed traits and seedling vigour of Cordia africana Lam.provenances in Ethiopia

Cordia africana is a very important indigenous tree species for timber and other products and services in Ethiopia.Seed traits and seedling vigour of seeds from 12 provenances of the species were compared.Mean seed mass for each provenance was assessed for 1000 seeds in10 replications,and seed length and width were measured for 100 seeds in four replications per provenance.Germination was assessed in a glasshouse taking 400 seeds from each provenance.Root collar diameter and height of 440 seedlings grown in a nursery for 290 days in Addis Ababa were measured.Seed length,seed width,seed mass,and shoot height and root collar diameter of seedlings showed significant differences(P0.001) among provenances.Correlation analysis between seed and seedling traits and environmental variables revealed significant positive correlations between seed width and germination percentage,seed width and altitude,seed width and longitude and seed length and latitude.Negative correlations were obtained between seed width and temperature,seed width and rainfall,seed mass and temperature,and germination and temperature of the seed source.As expected,differences in seed trait did not explain the variability in seedling vigour.Determining quantitative variations in seed traits and seedling vigour among provenances and the patterns along environmental gradients are essential for informing decisions on the tree improvement programme of the species.     

Range-Wide Genetic Variation in Port-Orford-Cedar (Cupressaceae,Chamaecyparis lawsoniana)

Abstract

Timing of height growth was determined for 54 families of seedlings of Chamaecyparis lawsoniana, Port-Orford-cedar, which represented most of its natural range. Seedlings were grown in plant beds in inland and coastal nurseries. The proportion of early-season growth declined and the proportion of late-season growth increased with changes in seed source location from high to low elevations, from south to north, and from east to west. This pattern was parallel to that of seedling height and of actual elongation in each of three periods during the growing season. The tallest trees (from the Oregon coast near the species' northern range limit) grew more in each period but had the greatest proportion of late-season height growth. Planting such genotypes where late summer drought or early fall frost are common may threaten their survival. Use of breeding zones that limit genotype transfer distance may avoid such damage. Within breeding zones, height growth of families was not related to their prior screening for disease resistance; selection for disease resistance should not affect growth rate or pattern. Seedlings grown at the coastal nursery had a lower proportion of early-season growth and more in late season than seedlings grown inland.     

Variation in seed and seedling traits and their relations to geo-climatic factors among populations in Yunnan Pine (<Emphasis Type="Italic">Pinus yunnanensis</Emphasis>)

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 geo-climatic 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.     

华北落叶松8个优良家系的种子萌发及苗期生长特性

为了比较华北落叶松初选优良家系的种子萌发特性和苗期生长性状,对8个家系和种子园混合株系、母树林及人工林种子的千粒重、饱满率等表型性状,室内发芽率和圃地发芽率等萌发特性,2a生苗的苗高、地径、生物量等生长性状进行了测量分析,结果表明:华北落叶松家系46、家系75、家系9和家系74的发芽率分别为96.00%、78.00%、90.00%和94.67%,苗高分别为35.6cm、33.0cm、32.8cm和31.4cm,地径分别为5.43mm、6.06mm、5.47mm和5.39mm;这4个家系在发芽指数、苗高和地径方面综合表现好于种子园、母树林和人工林,其隶属函数值为人工林的4倍以上,较母树林和种子园也高出35%以上。     

青海云杉半同胞子代苗期生长性状遗传分析

以青海云杉无性系种子园内30个青海云杉半同胞家系为研究对象,在张掖市肃南县塔尔沟苗圃开展苗期试验,测定5a生苗期苗高、地径、新梢长、侧枝数等生长性状。分析结果表明：（1）青海云杉半同胞子代苗家系间苗高、地径、新梢长存在极显著差异;遗传变异系数较高,均在19．76％以上,苗高、地径、新梢长、侧枝数指标的家系遗传力均较大,均在0．830以上;苗高与地径、新梢长间存在极显著正相关,地径与新梢长、侧枝数存在极显著正相关;（2）以苗高为首要选择指标,按照1倍标准差选择出158#、106#、160#、154#、109#、119#6个优良家系,各性状值高于30个家系的平均值。     

Genetic variation in progenies of 23 relic trees of Metasequoia glyptostroboides in their original habitat

Seeds of 23 relic Metasequoia glyptostroboides trees were randomly collected from their original, natural populations found in Lichuan City, Hubei Province, China. The seed characteristics and growth of their three-year-old progenies were investigated. Results show that the average intra-family coefficient of variation (CV) in height growth of the 23 three-year-old families was 14.53%, slightly higher than that of the inter-family CV (14.02%). Correspondingly, these two parameters for root-collar diameter growth were 15.44% and 13.15%. The 23 relic mother trees were significantly differed in their general combining abilities (GCA) and relative effect values of GCA (RGCA) of height growth and root-collar diameter growth over the three years. Both height and root-collar diameter growth had high family heritability in this seedling stage. After eliminating two inferior families, i.e., 15 and 46, 2.21% of genetic gain in height growth was obtained and 1.50% in root-collar diameter growth. It was also significantly different in crown size and number of branches among the 23 three-year-old seedling families. From a cluster analysis we concluded that eight families, i.e., 23, 28, 29, 30, 31, 33, 35 and 44 displayed superior GCA and RGCA in both height and root-collar diameter growth. Therefore, these relic mother trees displayed their potential as parents in seed orchards. With the exception of family 23, the other seven superior families were all collected at Guihua Village, Zhonglu Town, Lichuan City, which has been identified as an optimum district of M. glyptostroboides for seed collection.     

木荷优树子代苗期生长遗传和变异研究

利用设置在福建建瓯、浙江龙泉和淳安3个试验点的96～141个木荷优树自由授粉家系苗期测定材料,以研究和揭示其苗木生长和叶片形态性状的家系遗传变异规律.方差分析结果显示,木荷苗高、地径、叶片数、叶片长和叶片宽等在家系间的遗传差异皆达到极显著水平.性状遗传力估算值显示,苗高和叶片长分别受中等和较强的家系与加性遗传控制,而地径、叶片数和叶片宽等则受弱度至中等的家系和加性遗传控制.试验观测到,与来自较北部和较高海拔地区的家系比较,来自较南部和低海拔地区的家系在各区试点的苗木生长量大、叶片宽大、叶片数多,说明木荷苗木生长和叶片形态的家系效应中还存在明显的产地效应.木荷苗高和地径等不仅立地效应显著,而且存在显著的家系与立地互作效应.基于家系苗期测定结果,以苗高为标准,分别为水热条件较好的中心产区(福建建瓯)、一般产区(浙江龙泉)和水热资源较差的北缘区(浙江淳安)初选出20个速生的优良家系.     

Genetic variation for carbon isotope composition in Juglans regia L.: relationships with growth, phenology and climate of origin

? Among the traits of breeding interest for the common walnut tree Juglans regia L., characteristics such as timing of budbreak and leaf fall, water-use efficiency and growth performance are regarded as being of utmost relevance in Mediterranean conditions.

? The authors evaluated intraspecific variation in δ¹³C (carbon isotope composition, surrogate of intrinsic water-use efficiency, WUE_i) for 22 J. regia families grown in a progeny test under supplementary irrigation, and investigated whether such variation correlated with climatic indicators of native habitats. The genetic relationships between δ¹³C, growth and phenology were also assessed during two consecutive years.

? Overall, the most water-use-efficient families (i.e. with higher δ¹³C), which originated mainly from drought-prone provenance regions which have a high vapour pressure deficit and low rainfall, exhibited less height growth and smaller DBH. Using a stepwise regression procedure, δ¹³C was included as the main explanatory variable of genotypic variation in growth traits, together with growing season duration (for DBH in both years) and flushing (for height in 2007).

? It was concluded that WUE_i is largely unconnected to phenology effects in the explanation of growth performance for J. regia, therefore suggesting the opportunity of simultaneously selecting for low WUE_i and extended growing period to maximise productivity in non-water-limited environments.