柚木幼林生长表现初报

于1996年和1999年2次在海南省儋市雅里林场进行柚木引种试验，初步结果表明：柚木很适合在该地区栽培，首次引种林木5年生，树高和胸径生长量分别达到7．60m和8．54cm，年平均生长量为1．52m和1．171cm，其树高和胸径的生长曲线趋势还处于上升阶段；第二次引种林木2年生，树高和胸径平均生长量分别为4．53m和4．33cm，年平均生长量在2．0m和2．0m以上。目前两个林分子长势非常旺盛。     

7年生短枝木麻黄优良无性系选择的研究

以海南2个试验点上各含17个无性系的短枝木麻黄无性系为试验材料,进行树高、胸径、单株材积、主干分叉习性、主干通直度和保存率等6个性状的方差分析,并估算出6个性状的遗传相关和遗传力及指数选择等遗传参数。结果表明:无性系和地点的交互作用除了主干分叉习性有显著差异(p0.05)外,其他性状在无性系间差异均极显著(p0.001)。当不考虑无性系和地点互作时,无性系间不同性状的重复力均较高,为0.35 0.85,其中,树高重复力最高,主干分叉习性最低。遗传相关分析结果表明:树高、胸径、单株材积和保存率之间的表型及遗传存在极显著的正相关。树高、胸径、单株材积、主干分叉习性、主干通直度和保存率的平均遗传增益分别为6.5%、4.8%、10.9%、3.7%、1.5%和8.1%,筛选可获得明显的遗传增益。通过Smith-Hazel指数选择并按20%的入选率,选育出编号17、21和20三个优良无性系。     

False ring formation in teak (Tectona grandis L.f.) and the influence of environmental factors

Seedling anatomy and cross sectional discs of 8- and 12-year-old (juvenile) teak trees were examined for tree ring analysis and determination of environmental factors responsible for false ring formation in teak. Based on the anatomy and location within the true annual rings, four types of false rings were identified. The results from both cross-dating of plantation grown trees and controlled experiments, including induced drought, showed that rainfall during dry period, drought during active growing season, (container) polybag/field transplantation of seedlings and juvenility are the important causative factors of frequent false rings in teak. No definite relationship could be established between insect defoliation and the incidence of false rings. False ring formation in teak appears to be mainly a resultant feature of tree ring responses to different environmental and physical factors.     

Growth characteristics, stress-wave velocity, and Pilodyn penetration of 15 clones of 12-year-old Tectona grandis trees planted at two different sites in Indonesia

Tree improvement programs for teak (Tectona grandis) have mainly focused on breeding of trees with superior growth characteristics. However, improvement in wood quality should be included in breeding programs for high yield and high quality timber. In the present study, growth characteristics [stem diameter (D), tree height (H), and bole volume (V)], stress-wave velocity (SWV), and Pilodyn penetration (Py) were measured for 15 clones of 12-year-old teak trees planted at two different sites in Indonesia to clarify the variations in tree growth characteristics, SWV, and Py among clones, their repeatability, interaction between genotype and environment, and correlations between measured characteristics. Significant differences of all measured characteristics were found among 15 clones at both sites. Their repeatability showed relatively moderate to high values in both sites. These results indicate that these characteristics are closely related to genetic factors. Significant interaction between genotype and environment was found in all measured characteristics. In addition, SWV and Py showed lower interaction between genotype and environment than growth characteristics. No significant correlation was found between growth characteristics and SWV. These results suggest that wood properties and growth characteristics of teak trees can be improved by application of an appropriate tree breeding program.     

Assessment of enrichment planting of teak (Tectona grandis) in degraded dry deciduous dipterocarp forest in the Central Highlands,Vietnam

After years of unsustainable logging, dry deciduous dipterocarp forest (DDDF) has become poor in timber stocks and has been converted to industrial crops such as rubber. The objectives of this study were to assess teak (Tectona grandis L.f.) tree establishment under degraded DDDF conditions and to determine factors that influence the suitability of teak as a forest enrichment tree species. A set of 64 experimental plots of 4 900 m² each was set up and observed for 4–5 years for testing enrichment planting with teak under various combinations of two groups of factors: ecological conditions and forest status. Weighted, non-linear, multivariate regression models were used to detect key factors that influenced the suitability of teak. The results showed that at the age of 4 years the average dominant tree height (defined as 20% of the tallest trees in the experimental plot) reached 11.2, 7.8, 5.3 and 3.8 m for very good, good, average and poor suitability levels, respectively. Survival rates of planted teak from average to very good suitability levels were over 90%. Six key factors that affected the suitability of teak were waterlogging during the rainy season, altitude, stand volume of the degraded DDDF, soil type, percentage of sand and concentration of P₂O₅ in the soil. Under the extreme ecological and environmental conditions of the DDDF, enrichment planting with teak gave promising results.     

Hedonic Price Analysis of Teak Logs

Implicit economic values of physical attributes of teak logs (girth, length, straightness and soundness) were estimated using hedonic regression. The influence of spatial and temporal variations on teak wood prices was also estimated. The auction prices of teak wood at various Timber Sales Depots of the Forest Department of Kerala State in India during the period 2006–2010 were used for the study. Traders ascribed over 80 % of variation in teak wood prices to girth, straightness and soundness of logs. A reduction in age at felling of teak plantations in forest areas is proposed. The study also underlines the need to continue tree improvement programs and silvicultural operations for the production of high quality teak wood and thereby increase the profitability of teak plantations.     

Characterization of Lasiodiplodia theobromae (Pat.) Griffon & Maubl causing stem canker on Teak (Tectona grandis L.) in Ecuador

Teak is a very important tropical timber in Ecuador. In 2017, teak samples displaying stem canker symptoms were collected in two provinces of Ecuador. From 11 symptomatic trees, 11 isolates resembling a species of Lasiodiplodia were obtained. All isolates obtained induced stem canker on teak plants after artificial inoculation, confirming them as the cause of the observed canker symptoms. Bayesian inference with concatenated sequences of complete ITS and partial TEF-α and β-TUB gene sequences from two representative isolates clustered teak isolates with other sequences of Lasiodiplodia theobromae available in Genbank. This is the first report of L. theobromae causing stem canker on teak plants in Ecuador.     

Estimation of biomass and carbon stocks in plants,soil and forest floor in different tropical forests

An accurate characterization of tree carbon (TC), forest floor carbon (FFC) and soil organic carbon (SOC) in tropical forest plantations is important to estimate their contribution to global carbon stocks. This information, however, is poor and fragmented. Carbon contents were assessed in patula pine (Pinus patula) and teak (Tectona grandis) stands in tropical forest plantations of different development stages in combination with inventory assessments and soil survey information. Growth models were used to associate TOC to tree normal diameter (D) with average basal area and total tree height (H_T), with D and H_T parameters that can be used in 6–26 years old patula pine and teak in commercial tropical forests as indicators of carbon stocks. The information was obtained from individual trees in different development stages in 54 patula pine plots and 42 teak plots. The obtained TC was 99.6 Mg ha⁻¹ in patula pine and 85.7 Mg ha⁻¹ in teak forests. FFC was 2.3 and 1.2 Mg ha⁻¹, SOC in the surface layer (0–25 cm) was 92.6 and 35.8 Mg ha⁻¹, 76.1 and 19 Mg ha⁻¹ in deep layers (25–50 cm) in patula pine and teak, respectively. Carbon storage in trees was similar between patula pine and teak plantations, but patula pine had higher levels of forest floor carbon and soil organic carbon. Carbon storage in trees represents 37 and 60% of the total carbon content in patula pine and teak plantations, respectively. Even so, the remaining percentage corresponds to SOC, whereas FFC content is less than 1%. In summary, differences in carbon stocks between patula pine and teak trees were not significant, but the distribution of carbon differed between the plantation types. The low FFC does not explain the SOC stocks; however, current variability of SOC stocks could be related to variation in land use history.     

Herbivory, pathogens, and epiphylls in Araucaria Forest and ecologically-managed tree monocultures

Over the last centuries, natural forests have been replaced by extensive and homogeneous tree monocultures that cause strong impacts on ecological interactions and ecosystem processes. We expect, however, that ecologically-sustainable management practices can help to mitigate these effects. This study investigates how the replacement of Araucaria Forest by ecologically-managed tree monocultures affects leaf damage patterns produced by external chewers, internal chewers, leaf miners, galling insects, and pathogens, as well as the incidence of epiphylls. The study was performed in the São Francisco de Paula National Forest (southern Brazil) on 12 1-ha plots of Araucaria Forest and ecologically managed plantations of Araucaria, Pinus and Eucalyptus. Overall, 9955 leaves of the understory community (up to 1 m tall) were sampled and analyzed. The mean and the frequency distribution pattern of leaf damage were very similar between Araucaria Forest and all three tree monocultures. Also, there was no difference between habitats in the percentage of leaves attacked by different feeding guilds of insect herbivores and by pathogens. Araucaria Forest had a higher percentage of leaves with epiphylls than Eucalyptus plantation, probably due to its shadier and moister microclimate. Ecologically managed tree monocultures sustain a wide variety of herbivorous insects, pathogens and epiphylls which helps the maintenance of key ecological interactions and the functioning of the ecosystem.     

柚木花粉离体萌发试验

柚木(Tectona grandis L.f.)是世界名贵的用材树种,天然分布于印度、缅甸、泰国和老挝[1],具有生长快、用途广、纹理美观和价格昂贵的特点,已在热带、南亚热带地区广为引种,是世界上人工林种植面积最大的4个树种之一,也是单位面积产值最高的一个造林树种[2-3]。我国引种柚木已有170多年的     

Development of heartwood,sapwood,bark,pith and specific gravity of teak(Tectona grandis)in fast-growing plantations in Costa Rica

To elucidate the development of heartwood,bark,sapwood,pith and specific gravity of wood in fastgrowing teak(Tectona grandis)plantations in Costa Rica,we sampled three trees in each of 55 plantations and modelled each variable with age,site and different tree heights.Age and stand density of plantations were significant correlated with stem diameter at breast height and total height of the tree.Formation of heartwood was initiated at the age of 4-year-old and increased in direct proportion with age.The age of plantation had a significant relationship with stem diameter at breast height,heartwood percentage,sapwood thickness,sapwood percentage,percentage of bark,pith diameter and percentage,and specify gravity.The model for these tree parameters was model with these parameters as dependent variable and in relation to age as independent variable.     

Variation in tree growth characteristics, stress-wave velocity, and Pilodyn penetration of 24-year-old teak (Tectona grandis) trees originating in 21 seed provenances planted in Indonesia

Growth characteristics [stem diameter (D), tree height (H), and bole volume (V)], stress-wave velocity (SWV), and Pilodyn penetration (P) were measured for 21 seed provenances of 24-year-old teak trees planted in Indonesia to characterize variation in tree growth characteristics, SWV, and P among seed provenances. Broad-sense heritability and correlations between the measured characteristics were also determined. Significant differences for all measured characteristics were observed among provenances, indicating that these characteristics are genetically controlled. Broad-sense heritabilities of growth characteristics, SWV, and P are moderate values. These results indicate potential for improving growth characteristics and wood properties of teak trees with the help of breeding programs. Highly significant positive correlations were observed among the growth characteristics, suggesting that they are closely related. In contrast, no significant correlations were observed between the growth characteristics and SWV, indicating that they are independent. We conclude that mechanical properties are also important criteria for selecting plus trees in tree breeding programs. Principal component analysis revealed that seed provenances from Indonesia (Bangilan, Deling, and Randublatung) and India (Malabar and Central Province) have high scores of growth characteristics and SWV.     

Genetic and morphological variation in natural teak （Tectona grandis） populations of the Western Ghats in Southern India

Teak(Tectona grandis L.f.) is a popular hardwood species native to South and South-East Asia. The possible association of amplified fragment length polymorphism(AFLP) marker with morphological variables of eleven important characters viz. girth at breast height(GBH), height of tree, bole height, branch knots, presence of fluting, spiral stem, leaf hair, leaf length/breadth ratio, branching pattern, bark colour and petiole shape for nine natural populations comprising 180 genotypes of teak(9 populations × 20 trees). The phenogram constructed using Euclidean distances for the eleven morphological characters showed that the populations were not grouped according to their geographical origin. The Mantel's test for pairwise correlation between Euclidean distances of different morphological variables and genetic distances from AFLP data revealed that only petiole character(r =0.269; p =0.046) and height of tree(r =0.200; p =0.001) were significantly correlated with that of AFLP data matrix. The nine populations in this study covered a geographic area of about 1000 km stretch along the Western Ghat of South India. A test of correlation between genetic and geographic distance matrices revealed a significant positive correlation(r =0.475; p =0.009). The lack of perfect congruence between morphological and molecular data except for geographic distance, tree height and petiole character suggested that the morphological system might be useful for the morphotypes management but not appropriate to study the genetic structure of the teak populations.     

Stand characteristics and downed woody debris accumulations associated with a mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak in Colorado

Lodgepole pine (Pinus contorta Dougl. ex Loud.)-dominated ecosystems in north-central Colorado are undergoing rapid and drastic changes associated with overstory tree mortality from a current mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak. To characterize stand characteristics and downed woody debris loads during the first 7 years of the outbreak, 221 plots (0.02 ha) were randomly established in infested and uninfested stands distributed across the Arapaho National Forest, Colorado. Mountain pine beetle initially attacked stands with higher lodgepole pine basal area, and lower density and basal area of Engelmann spruce (Picea engelmannii [Parry]), and subalpine fir (Abies lasiocarpa (Hook.) Nutt. var. lasiocarpa) compared to uninfested plots. Mountain pine beetle-affected stands had reduced total and lodgepole pine stocking and quadratic mean diameter. The density and basal area of live overstory lodgepole declined by 62% and 71% in infested plots, respectively. The mean diameter of live lodgepole pine was 53% lower than pre-outbreak in infested plots. Downed woody debris loads did not differ between uninfested plots and plots currently infested at the time of sampling to 3 or 4–7 years after initial infestation, but the projected downed coarse wood accumulations when 80% of the mountain pine beetle-killed trees fall indicated a fourfold increase. Depth of the litter layer and maximum height of grass and herbaceous vegetation were greater 4–7 years after initial infestation compared to uninfested plots, though understory plant percent cover was not different. Seedling and sapling density of all species combined was higher in uninfested plots but there was no difference between infested and uninfested plots for lodgepole pine alone. For trees ≥2.5 cm in diameter at breast height, the density of live lodgepole pine trees in mountain pine beetle-affected stands was higher than Engelmann spruce, subalpine fir, and aspen, (Populus tremuloides Michx.), in diameter classes comprised of trees from 2.5 cm to 30 cm in diameter, suggesting that lodgepole pine will remain as a dominant overstory tree after the bark beetle outbreak.     

Effects of defoliation by Eucalyptus weevil, Gonipterus scutellatus, and chrysomelid beetles on growth of Eucalyptus globulus in southwestern Australia

Plantations of Eucalyptus globulus in southwestern Australia are defoliated by Eucalyptus weevil, Gonipterus scutellatus, and a complex of chrysomelid and scarab beetles, yet there is no information on the impact of beetle defoliation to tree growth in southwestern Australia. To address this shortcoming, we used insect exclusion trials, to compare growth of insecticide treated (and thus relatively undamaged) trees with untreated (and thus defoliated) trees to determine whether defoliation by G. scutellatus and other beetles reduced the growth and harvest volume of E. globulus trees. Our results showed some evidence of beetle defoliation reducing growth of E. globulus. Mean defoliation levels of the growing tip of untreated trees ranged from 18% to 33% across the duration of the study and were significantly greater than mean defoliation levels of 5–16% on insecticide treated trees. Seasonal peaks in defoliation of 30–80% to the growing tip of untreated trees were recorded between late spring and early autumn. The greatest impact of defoliation on tree growth was evident during the 2.5 year period of insect exclusion, when higher relative growth rates were recorded for insecticide treated trees, which were significantly different from relative growth rates of untreated trees at two of the four plantations. However, our results showed only a limited impact of beetle defoliation on the total volume at harvest. Initially small trees tended to suffer more severe defoliation than initially large trees. Effects of insect exclusion treatment on harvest volume were modified by the initial tree size and the relationship between the initial tree size and levels of defoliation.     

英德火炬松种子园子代在粤北的生长规律研究

火炬松(Pinus taeda L.)原产美国东南部,为美国东南部的主要造林树种,具有生长快、适应性强、材质好、抗病虫害强的特点,是美国南方松中分布最广、蓄积量最多的树种,也是工业原料林和薪炭林树种[1].     

枫香优树14年生子代遗传变异及选择

在福建省洋口国有林场,对来自安徽省南部黄山地区的53个枫香家系进行子代测定,研究家系的遗传变异规律,开展优良家系及单株选择.结果表明:子代试验林14年生时,树高、胸径和单株材积平均值分别为8.05m、6.30cm和0.014 93 m3,生长性状的家系遗传力为0.437～0.576,受中强度的遗传控制,单株遗传力为D.113～0.195,受较弱的遗传控制;木材材性的家系遗传力为0.507～ 0.591,单株遗传力为0.360～0.500,均受中强度的遗传控制.以生长量为主要指标,选出速生优良家系9个,其树高、胸径和单株材积平均值分别为8.85 m、7.22 cm和0.021 49 m3,遗传增益分别为2.86％、5.47％和13.4％;从木材基本密度大于0.500 g·m-3的家系中选出7个生长材性兼优家系,树高、胸径、单株材积和木材基本密度的平均值分别为8.34m、6.79 cm、0.018 58 m3和0.518 g·m-3.所选出的速生优良家系和生长材性兼优家系可作为枫香育种材料在生产上推广应用.     

Influence of fly ash mixtures on early tree growth and physicochemical properties of soil in semi-arid tropical Alfisols

The beneficial effects of planting mixtures comprising of fly ash at the rate of 66%, 33% and 17% by soil volume were assessed for the early growth of two economic tree species, teak (Tectona grandis) and leucaena (Leucaena leucocephala) in rainfed Semi-Arid Tropical (SAT) Alfisols in India. Measurements of tree growth were made at six monthly intervals over a 3-year period. Fly ash at 66% by soil volume of the planting pit significantly increased the diameter of teak at breast height (dbh). In leucaena, application of fly ash at 17% by soil volume was found to be effective in increasing dbh during most of the study period. Changes in soil physicochemical properties (bulk density, water retention at 0.033 and 1.5 MPa, profile moisture content, pH, soluble salt content and organic carbon) were simultaneously studied. Among these soil properties, plant available water (PAW) and organic carbon (OC) contents explained variations in diameter at breast height (dbh) in teak during most of the sampling period, while none of the soil properties significantly explained dbh in leucaena. The highest dose of fly ash applied (66% by volume) decreased bulk density (BD) and increased PAW in teak and to an extent in leucaena during the first 2 years of tree growth. Higher profile moisture content was noted in pits treated with 66% fly ash during the dry period of November (after the end of seasonal rainfall which occurred from June to October) during the first and second year after application. An erratum to this article can be found at     

Stem deformation in young plantations of black spruce (Picea mariana (Mill.) B.S.P.) and jack pine (Pinus banksiana Lamb.) in the boreal forest of Quebec,Canada

Stem deformation has often been observed in young black spruce (Picea mariana (Mill.) B.S.P.) and jack pine (Pinus banksiana Lamb.) plantations. Whenever important stem deformations are observed at the time of harvesting, timber value is negatively affected especially during the wood transformation process. The present work was undertaken to quantify and qualify the importance of stem deformation of black spruce and jack pine in the boreal forest of central Quebec at the stand and tree levels. In 30 black spruce and jack pine plantations, approximately 22% of spruce trees and 27% of pine trees exhibited stem deformation. The proportion of deformed trees was higher in the youngest plantations and decreased with the age of the plantations. Stem deformation caused the formation of compression wood which is another factor that can reduce the value of wood products. Thirty-nine black spruces and 34 jack pines were analysed at the tree level. On average, compression wood represented 14% and 20% of stem volume in 7- and 10-year old black spruce plantations, respectively. These proportions ranged from 18% in the youngest jack pine plantation to 26% in the oldest one. Stems of both species classified as normal contained a lower volume of compression wood than stems classified as deformed or very deformed. Annual percentages of compression wood and annual shoot length increased significantly with tree age (p < 0.0001 for both variables). Statistically significant correlations were also found between the range of displacement of the stem and the percentage of compression wood. The fewer number of trees with deformed stems in older plantations combined with high compression wood formation suggests that, over time, a deformed tree can become normal and straight in appearance.     

接种不同真菌菌株后黄栌生物电指标的变化

以黄栌枯萎病发病植株的根部所分离到的3种优势菌株作为供试菌株,利用新型电感电容表和电导率仪分别测定黄栌的树干电容、电阻和叶片电导率等生物电指标的变化,发现接种不同真菌菌株后黄栌的树干电容均值都呈现逐渐下降的趋势,树干阻抗均值、叶片细胞外渗液的相对电导率和叶片离子外渗百分率则都呈现逐渐增大的趋势。但接种Verticillium dahliae后黄栌出现枯萎病症状,且各项生物电指标均呈现更为显著的变化,其变化幅度较分别接种Fusarium sp.、Cylindrosporium sp.菌株后的电指标变化幅度大,而且树干电容和电阻在接种5 - 7天后表现出显著差异性,比病害症状出现提前7 - 10天;同时,受Verticillium dahliae侵染的植株和未受侵染植株在树体干部电容、阻抗和单位电容指标上差异显著,树干电阻与树干电容在植株受侵染后表现出更为显著的负相关关系。