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.     

Growing stock variation in different teak （Tectona grandis） forest stands of Mizoram,India

The growing stock assessment of three different teak forest stands （Tuirial： 500 m asl, Sairang： 200 m asl and Phunchawng： 550 m asl） was done in 2006 in Mizoram, India. Five diameter classes were arbitrarily established for knowing the volume attribute data and population structure, viz. a （10-20 cm）, b （20-30 cm）, c （30-40 cm）, d （40-50 cm）, and e （50-60 cm）. Results revealed that the density of the individuals among the studied stands varied from 280 stems/ha to 620 stems/ha. The average diameter of all the individuals ranged between 27.48 cm and 35.43 cm. Similarly, the average height was oscillated between 17.87 m and 22.24 m. The total basal area was recorded between 24.28 m2.ha-1 and 45.80 m2.ha＂l. The maximum and minimum values of total growing stock under all the diameter classes were 669.01 m3.ha-1 and 284.7 m3.ha-1, respectively. The representation of population structure of different stands explained that the perpetuation of this species was ensured for a quite long time.     

印度米佐拉姆不同柚木林分生长蓄积量变异(英文)

评估了印度米佐拉姆3种柚木林分(Tuirial:500m asl,Sairang:200m asl和Phunchawng:550m asl)在2006年生长蓄积量。为了掌握柚木体积特性和种群结构,随机建立5个直径等级,即a(10-20cm),b(20-30cm),c(30-40cm),d(40-50cm),和e(50-60cm)。研究表明,研究地内个体密度在280-620stems·hm-2之间,平均直径在27.48—35.43cm之间,平均高度为17.87-22.24m,总的基础面积为24.28-45.80m2·hm-2,最大和最小总生长蓄积量分别为669.01m3·hm-2和284.7m3·hm-2。该物种现有种群结构确保其可以长期存在。     

Morphological parameters and genetic diversity of progenies from seed production areas and unimproved stands of teak (Tectona grandis L.f.) in India

We compared morphological and genetic attributes of prog-eny obtained from three seed production areas (SPAs) and three corre-sponding unimproved stands (UIS) of teak (Tectona grandis L.f) at three bro...     

柚木黑色条纹心材的颜色和化学特性

印尼岛的柚木心材在年轮周围显示了不规则的黑色条纹变化。本研究调查柚木黑色条纹心材的颜色和化学特性。利用色坐标（CIELAB）测定颜色特性（pH值、无机物含量、抽出物含量和特性）。结果表明：黑色条纹的颜色较对照少12-15个亮度单位。因此,黑色条纹的颜色与对照比较,有较多的红色,较少的黄色、色彩和色度。黑色条纹心材部分的pH值灰度含量和钙含量都比对照的高。黑色条纹的心材抽出物含量较对照的高。推测当生物活性物质（杀虫剂）明显增加时,心材显示发黑的过程可能是一种防御机制。     

Effect of auxins on axillary and de novo shoot regeneration from in vitro shoot cultures derived from forced epicormic buds of teak (Tectona grandis L.)

In this presentation,we report on de novo and axillary shoot regeneration and rooting of shoots maintained over a long term,from cultures of Tectona grandis L.Shoot-tips of teak shoots forced from epicormic buds were used as the starting material for axenic shoot-culture establishment.Long term maintenance of such axenic shoot cultures was carried out by regular sub-culturing on MS media supplemented with N 6-benzyleadenine (BA,8.8 μmol L-1) and indole-3-butyric acid (IBA,2 μmol L-1) for 24 months.Vigorously growing shoot tips (2 3 cm long) were inoculated on the MS basal medium supplemented with different concentrations (0,1,2,4,6,8 or 10 μmol L-1) of either IBA or α-naphthaleneacetic acid (NAA) for rooting.Axillary and de novo shoots were developed from axillary and cut basal ends of shoots,respectively.Shoots growing on auxins were further sub-cultured (every 15 days) and maintained for 45 days.The greatest number of de novo (5.06) as well as axillary shoots (2.85) was observed on the MS medium supplemented with 10 μmol L-1 NAA or 8 μmol L-1 IBA,respectively,after 45 days.The combinations of both IBA (μmol L-1) + NAA (μmol L-1) were tested at different concentrations (4 + 4,6 + 6,8 + 8) supplemented to a half strength MS basal medium with 0.1% activated charcoal for rooting of decapitated and non-decapitated de novo and axillary shoots.Rooting from non-decapitated de novo shoots was highest (93.33%) with a mean number of roots of 4.61 on this medium,supplemented with 6 μmol L-1 IBA + 6 μmol L-1 NAA,after 36 days of initial culture.Individual auxin,however,was not effective for root induction.Rooted shoots were acclimatized in a green house and after four weeks plantlets were transferred to the field.     

Trait variations in 28-year-old teak (Tectona grandis) provenance field trials in Ghana,West Africa

Stem straightness, axis persistence, presence/absence of protuberant buds and epicormics, diameter and height have profound influence on timber quality and volume of teak (Tectona grandis). Provenance trials of teak were established in the 1970s in Ghana, as part of the Food and Agriculture Organization (FAO) International Series of Provenance Trials, with the view of selecting teak germplasm for sites with specific environmental conditions. Two field trials were located in dry semi-deciduous (dry) and moist semi-deciduous (moist) ecological zones of Ghana. They consisted of 13 provenances, including four landraces each from Ghana and Indonesia, and two and three provenances from India and Laos, respectively. Trees were assessed at 9, 17 and 28 years to (1) quantify the potential variation in quality and timber volume production, (2) examine possibilities for determining early selection of parameters of superior provenances and (3) select provenances for sites with particular environmental conditions. Production traits were higher on the moist site than the dry site. Mean height was 23.2 and 20.2 m tree^?1, stem cross-sectional area at breast height was 0.0896 and 0.0474 m² tree^?1, and stem volume was 0.75 and 0.34 m³ tree^?1 for the moist and dry sites, respectively. Nilambur provenance from moist India had the highest mean stem straightness score of 19% above average, whereas Savannakhet from Laos had the best protuberant bud score with 18% of the trees above average. Indonesian landraces performed better in the dry zone, whereas provenances from India and Laos performed better in the moist zone. Phenotypic correlations between age 9 and 28 years were moderate (r 0.54–0.90) to high (r > 0.90) for production and qualitative characteristics, indicating feasibility of early assessment for identification of superior provenances. Nilambur and Savannakhet II provenances proved to be favourable choices for the moist zone, whereas the Temandsang provenance from Indonesia was found to be the best choice for the dry site.     

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.     

Seasonal variation in the biomass and non-structural carbohydrate content of fine roots of teak (Tectona grandis L. f.) plantations in a dry tropical region

Seasonal variation in the biomass and total non-structural carbohydrate content (TNC) of fine roots of teak (Tectona grandis L. f.) were studied in 19- and 29-year-old plantations in a dry tropical region. Fine root TNC content was highest during the dry summer (May), and lowest in the early part of the rainy season (July). Generally, seasonal trends in TNC content were the opposite of those in fine root biomass. The TNC concentration of roots increased with diameter and decreased with soil depth. In the 19-year-old plantation, fine root TNC content was approximately 12% higher than in the 29-year-old plantation.     

Effects of calcium, boron and nitrogen fertilization on the growth of teak (Tectona grandis) seedlings and chemical property of acidic soil substrate

Many teak plantations are established on acidic soils with low nutrient availability. There is also poor documentation of nutrient budgets for teak, therefore, a pot experiment with optimal hybrid regression design (Roquemore R311A) was implemented with calcium, boron and nitrogen treatments with teak seedlings (Tectona grandis L.f.) planted in acidic lateritic red soil substrate. Seedling growth, biomass production and root development, and soil pH, and exchangeable Ca and Al concentration were measured. Plant height, root collar diameter, biomass of leaves, stems and roots, root volume, taproot length, number of lateral roots of teak seedlings were significantly and positively correlated with soil exchangeable Ca, pH and Ca/Al molar ratio, and negatively correlated with exchangeable Al. All growth traits were significantly affected by calcium, nitrogen and their interaction, but B fertilizer and other interactions had insignificant effects. To effectively cultivate teak seedlings in acidic soil substrates, 1.68 g kg⁻¹ quicklime (CaO) and 0.65 g kg⁻¹ urea was suggested to be added to neutralize soil acidity, and enhance soil exchangeable Ca content and Ca/Al molar ratio. Urea should not be added without quicklime.     

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.     

Growth,survival, carbon rates for some dry tropical forest trees used in enrichment planting in the Cerro Blanco protected forest on the Ecuadorian coast

Deforestation principally to establish cattle pastures has created large expanses of land dominated by exotic grass prior to the establishment of the Cerro Blanco Protected Forest in Ecuador. A dry forest restoration program was carried out from 2008 to 2017. Tree planting sites were cleared in parallel lines through abandoned pasture and secondary vegetation using manual labor. Native tree species were produced in a nursery on site and used in yearly plantings during the rainy season. A total of 637 hectares were planted at an average stocking density of 1,000 trees per hectare. Growth data was collected from trees planted in nine sites from 2008 to 2017. Mortality rates were determined from a sample of 400 trees of twenty-two species. Survival of all species was greater than 50%. Ten species had survival rates greater than 90%. Vitex gigantea, with high survival rates, also had significantly greater growth rates than the other species (p < 0.0001) and showed the greatest yearly accumulation of total carbon (2.07 Kg C yr ^?1 stem^?1). Other species with high growth rates were Cordia alliodora and Centrolobium ochroxylum. This restoration program demonstrates that the dry forest restoration with timely maintenance and protection from fire and grazing is possible with intensive tree planting of native species.     

Importance of forest structure versus floristics to composition of avian assemblages in tropical deciduous forests of Central Highlands,India

We investigated how much forest structure and floristics independently contributed to the composition of avian assemblages at multiple scales and for individual foraging guilds in tropical deciduous forests of Central Highlands, India. We derived dissimilarity matrices between all pairs of the 36 sampling sites with respect to forest structure, floristics, and bird species composition and ran Mantel's randomization tests to detect significant associations among the matrices after partialling out the effect of geographic distance between sites. Bird species composition was found to be significantly related to forest structure across habitats, and floristics within the moist-deciduous forests. This finding is consistent with earlier observations that birds respond, in their species composition, to vegetation structure across habitats and to vegetation composition within a habitat. As predicted, the composition of insectivorous birds was influenced by forest structure, but the phytophagous guild did not show any relation to vegetation composition in contrast to patterns observed elsewhere. We explain this anomaly as a result of availability of a wide choice of food plants for phytophagous birds in central Indian tropical forests and weak species–environment relationships on account of their nomadism. Extraction of non-timber forest products remains a key economic activity in central India and our results imply that it can potentially influence the composition of forest bird communities through alteration of forest structure and floristics.     

Soil carbon stock assessment in the tropical dry deciduous forest of the Sathanur reserve forest of Eastern Ghats,India

Climate change and carbon mitigation through forest ecosystems are some of the important topics in global perspective. Tropical dry forests are one of the most widely distributed ecosystems in tropics, which remain neglected in research. The soil organic carbon (SOC) stock was quantified on a large scale (30 1-ha plots) in the dry deciduous forest of the Sathanur reserve forest of Eastern Ghats. The SOC stock ranged from 16.92 to 44.65 Mg/ha with a mean value of 28.26 ± 1.35 Mg/ha. SOC exhibited a negative trend with an increase in soil depth. A significant positive correlation was obtained between SOC stocks and vegetation characteristics viz. tree density, shrub basal area, and herb species richness, while a significant negative correlation was observed with bulk density. The variation in SOC stock among the plots obtained in the present study could be due to differences in tree abundance, herb species richness, shrub basal area, soil pH, soil bulk density, soil texture etc. The present study generates a large-scale baseline data of dry deciduous forest SOC stock, which would facilitate SOC stock assessment at the national level as well as to understand its contribution on a global scale.     

Comparative regeneration status in a natural forest and enrichment plantations of Chittagong （south） forest division, Bangladesh

于2002年4月至11月,对孟加拉Chittagong (南部)林区天然纯林和肥沃地人工林树种更新情况进行了比较研究。共设100个3m×3m的样地(天然林50个,人工林50个)。共记录天然林更新树种64个,苗木密度为24767株/hm2;人工林更新树种40个,苗木密度为18633株/hm2。天然林更新量最大的树种为Castanopsis spp.(2200 株/hm2),其次是Glochidion lanceolarium (2183 株/hm2);人工林更新量最大的树种为Dipterocarpus gracilis (2117株/hm2),其次是Anogeissus acuminata (2000株/hm2)。对天然林而言, Castanopsis spp 的相对密度最高(8.88%), Glochidion lanceolarium 的相对频度最高(7.36%),Syzygium spp. 的相对富有度最高(3.79%),Glochidion lanceolarium的重要值指数最高(18.24%);对人工林而言,Dipterocarpus gracilis的相对密度最高(11.36%),Glochidion lanceolarium的相对频度最高 (9.71%), Dipterocarpus gracilis的相对富有度最高(5.92%), Glochidion lanceolarium的重要值指数最高 (23.32%)。Dipterocarpus gracilis 常见种在天然林和人工林都有更新苗木,但人工林的苗木要高于天然林。天然更新的苗木非常密集,但由于人为的干扰,这些更新的苗木通常达不到径干生长期。表4参35。     

Yield and Nutrient Content of Chestnut (<Emphasis Type="Italic">Castanopsis piriformis</Emphasis>) in Natural Central Highlands Forests,Vietnam

Chestnuts have historical importance as a food source worldwide. Planting of chestnuts has focused on a few species, including Castanea dentata, Castanea sativa, Castanea mollissima, and Castanea crenata, although others species are also edible. Castanea species are members of the beech family (Fagaceae) and are native to tropical and temperate areas. In this study, the yield and nut quality of Castanopsis piriformis in natural forests of the Central Highlands of Vietnam were investigated to provide evidence that C. piriformis is worth growing as a food species. Data were collected from 12 plots of 50 m × 50 m size located in four altitude zones. Nuts were collected from three to five chestnut trees in each plot judged to be of typical sized based on diameter at breast height and crown diameter. Average dry yield of nuts was found to be elevation-dependent, being highest at 500–1000 m (1152 kg/ha/year), decreasing to 815 kg/ha/year below 500 m, and to 770 kg/ha/year at 1000–1500 m. The lowest yield was observed at above 1500 m (252 kg/ha/year). Protein and lipid contents in the kernels of C. piriformis chestnut were 4.4 and 0.1 %, respectively. Glucose accounted for 73.1 % and was significantly higher than that of commercially grown Castanopsis boisii chestnuts in Northern Vietnam. With the current price of 0.6 US$/kg nuts, collecting nuts growing in natural forest can bring at least 480 US$/ha/year to local people. These results indicate the possibility of growing and consuming C. piriformis chestnut as a crop to decrease poverty. However, governmental support is required for the sustainable development of C. piriformis.     

Mineralization processes in some samples from the fossil forest of Dunarobba (Umbria, Central Italy)

 Two isolated twigs (samples A and B) from the site of the fossil forest of Dunarobba (Central Italy) were examined to assess both the degree of degradation of the organic fraction and the composition of the inorganic component. Sample A, although showing the presence of minute crystals, is mineralised only to little larger extent with respect to the trunks of the fossil forest and exhibits a wood composition almost comparable to that of the fossil forest. Main minerals are silica, calcite, chloroapatite, chloromagnesite, and clays. Residual terpenes perfectly match, as either components or proportions, those found in the fossil forest trunks. Sample B is much more mineralised and physical parts are hard (sample BII, 84% mineralisation) along with others that are quite loose (sample BI, 62% mineralisation). Goethite constitutes the major mineral in both parts. Calcite, on the contrary, is higher in BII than in BI. In agreement with the literature, goethite is present in the interstitial spaces of the cell walls whereas calcite is found in the cell lumina. The wood components are limited to lignin and terpenes; being absent cellulose or other polysaccharides. BI contains the same types of terpenes present in the fossil trunks, whereas only diterpenes have been found in BII. The samples B contain, with respect to either sample A or fossil trunks, a lower content of fully or partly aromatic sesquiterpenes and diterpenes. This fact is probably due to the oxidative environment of iron deposition. The difference in the mineralogical structures exhibited by the two samples must be searched in the different environmental conditions under which the samples were maintained. In particular, an essential role must have been played by water sources much richer in soluble salts and more differentiated than the current spring waters of the region. Received 6 March 1999