モクホンヒシショクブツニオケルアテザイノソシキトソノタヨウセイニカンスルケンキュウ

博士（農学)東京農工大

Geographic variations of wood properties of Larix sibirica naturally grown in Mongolia

Geographic variations in growth, stress-wave velocity of stem, dynamic Youngâs modulus of stems and logs, annual ring width, latewood percentage and basic density were investigated for (Münchh.) Ledeb. naturally grown in Mongolia. A total of 250 trees with 20 to 30 cm in stem diameter at a height of 1.3 m above ground level were selected from each natural stand in five different provenances in Mongolia. In addition, five trees in each stand were cut for measuring dynamic Youngâs modulus of stems and logs, annual ring width, latewood percentage and basic density. Mean values of stress-wave velocity of stems in each stand ranged from 2.92 to 3.41 km s, and the mean value of five stands was 3.23 km s. Mean values of dynamic Youngâs modulus of logs in each stand ranged from 5.17 to 9.72 GPa. A significant correlation (â=â0.798, â<â0.01) was found between stress-wave velocity of stems and dynamic Youngâs modulus of logs. Among the five stands, the highest and the lowest values of average annual ring number were 193 and 44, respectively. Mean values of basic density in five trees within each stand were examined and ranged from 0.52 to 0.56 g cm. Significant differences among five stands were found in tree height, stress-wave velocity of stem, dynamic Youngâs modulus of stems and logs, annual ring width and latewood percentage, suggesting that trees naturally grown in Mongolia have geographic variations in mechanical properties of wood.Larix sibiricaâ1â1rpâ3L. sibiric

Secondary xylem maturation evaluated by modeling radial variations in anatomical characteristics and wood properties of Shorea macrophylla (De Vr.) Ashton planted in Sarawak, Malaysia

Radial variations in anatomical characteristics and wood properties were investigated in 23-year-old Shorea macrophylla (engkabang) trees planted in Sarawak, Malaysia. The efects of radial growth rates on anatomical characteristics and wood properties and the manner of xylem maturation were determined based on selected mixed-efects models. The best models of radial variation were ftted by linear functions for wood fber length, wood fber wall thickness, basic density, and compressive strength. Logarithmic functions were applied for vessel element length and vessel frequency, and quadratic functions were applied for vessel diameter and wood fber diameter. Vessel diameter and wood fber length were afected by radial growth rates although these efects on the other properties were minimal. In the fxed part of the models, the results showed small mean absolute error values of radial variation in relation to the distance from the pith according to vessel frequency and vessel diameter. In contrast, in relation to the estimated cambial age, smaller mean absolute error values were obtained for cell length, wood fber traits, and basic density, suggesting that all properties varied from pith to bark in relation to the cambial age, except for vessel traits. Thus, in S. macrophylla, xylem maturation in cell length, wood fber traits, and basic density were due to cambial age rather than diameter growth, but xylem maturation in vessel traits depended on diameter growth

Basic wood properties of Borneo ironwood (Eusideroxylon zwageri) planted in Sarawak, Malaysia

The aim of this study is to obtain the basic wood properties of planted Borneo ironwood (Eusideroxylon zwageri) from a plantation established about 80 years ago. Stem diameter at 1.3 m above the ground, tree height, and stress-wave velocity (SWV) of stem were measured on 36 planted E. zwageri trees. Later, core samples were collected from four trees whose measurements represented the average stem diameter of all the measured trees. Using the core samples, the moisture content (MC), basic density (BD), and compressive strength parallel to grain (CS) were measured. Dynamic Youngʼs modulus for longitudinal direction at green condition (E) was also calculated from SWV. There was no significant relationship between growth characteristics and SWV. Mean values of MC, BD, CS, and E were 37.2 %, 0.86 g/cm3 , 64.3 MPa, and 18.47 GPa, respectively. Significant differences among individual trees were found in MC, BD, and CS. In addition, radial variations were almost constant from bark side to pith side. The results indicate that longitudinal E is independent from growth characteristics, and that the E. zwageri wood tested in this study has uniform BD and CS in the radial direction

Selection of Eucalyptus camaldulensis Families for Sustainable Pulpwood Production by Means of Anatomical Characteristics

Sustainable pulpwood production from fast-growing tree plantations is needed for pulp and paper industries. To increase the pulpwood production efficiency, the anatomical characteristics and derived-wood properties of 75 trees from 15 half-sib families of Eucalyptus camaldulensis Dehnh. planted in Thailand were investigated, and then the family was classified by suitability of wood as raw material for pulp and paper products using principal component analysis and clustering. The mean values of vessel diameter, vessel frequency, fibre diameter, fibre lumen diameter, and fibre wall thickness at 2 cm from the cambium were 128 &micro;m, 16 no./mm2, 11.1 &micro;m, 7.1 &micro;m, and 1.88 &micro;m, respectively. In addition, the Runkel ratio, Luce&rsquo;s shape factor, flexibility coefficient, slenderness ratio, solids factor, and wall coverage ratio (i.e., derived-wood properties) were 0.53, 0.42, 0.64, 85.3, 68 &times; 103 &micro;m3, and 0.34, respectively. Significant differences in fibre diameter, fibre lumen diameter, and Runkel ratio were found among families. Although significant differences among families were not found for other anatomical characteristics and derived-wood properties, the p-values obtained by an analysis of variance test ranged from 0.050 to 0.088. Based on the results of a principal component analysis and cluster analysis, 15 families were classified into four clusters with different expected pulp and paper characteristics. The suitability of wood from E. camaldulensis half-sib families for pulp and paper can be evaluated by principal component analysis using anatomical characteristics and physical properties as variables. Based on the results, desirable pulp and paper quality may be obtained through the selection of families from this species

Preliminary evaluation of anatomical characteristics of four common Mongolian softwoods

To effectively and sustainably utilize wood resources from boreal forests in Mongolia, anatomical characteristics, tracheid morphology, cell proportion, annual ring width, and latewood percentage were preliminary determined in Pinus sylvestris, Pinus sibirica, Picea obovata, and Larix sibirica trees naturally growing in Mongolia. Based on the observation, the anatomical characteristics of four common Mongolian softwoods were the same as those previously observed in the same species or the same genus species. Based on the parameters of the Gompertz functions for annual ring width, silvicultural management, such as thinning timing and harvesting age, should be considered depending on the species when the plantation is established. The results of the model selection for relationships between latewood percentage and basic density indicated that the increase ratio of basic density corresponded to an increase of latewood percentage is almost the same irrespective of species, although there are species-specific values of basic density corresponding to specific latewood percentages. The results obtained in the present study contribute effective and sustainable utilization of wood resources from Mongolian forestry. © 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group

The complete mitochondrial genome sequence of the medicinal fungus Inonotus obliquus (Hymenochaetaceae, Basidiomycota)

Inonotus obliquus is a medicinal fungus in the family Hymenochaetaceae and commonly known as chaga. The sclerotium of this fungus has been used as a traditional medicine for long time. In this study, we present the mitochondrial genome sequence of I. obliquus. The mitochondrial DNA (mtDNA) is 119,110 base pairs in length and contained genes for 58 Open reading frames, 2 ribosomal RNAs, and 30 transfer RNAs. Consequently performed phylogenetic analysis indicates that this fungus is closely related to Sanghuangporus sanghuang which belongs to the same family Hymenochaetaceae. We first reported about the complete mitochondrial genome of fungi belonging to the genus Inonotus

Wood Properties of Three Fruit Tree Species Planted in Central Kalimantan, Indonesia

The objective of this study was to evaluate the properties for wood utilization of fruit trees planted in Central Kalimantan, Indonesia. A total of 9 jambu bol (Syzygium malaccense), rambutan (Nephelium lappaceum), and durian (Durio zibethinus) trees were randomly selected from the plot (20 by 30 m) and measured for stem diameter, tree height, stress-wave velocity (SWV), and Pilodyn penetration of the trees. Mean values of stem diameter were 11.8, 15.9, and 29.3 cm for S. malaccense, N. lappaceum, and D. zibethinus, respectively. Mean values of stress-wave velocity were 3.16, 3.95, and 3.63 km/s for S. malaccense, N. lappaceum, and D. zibethinus, respectively. Core samples (5 mm in diameter) were collected from these trees to investigate the wood properties [basic density (BD) and compressive strength parallel to grain (CS)], anatomical characteristics [vessel diameter (VD), cell wall thickness (CWT) in wood fiber, and cell length (CL) of wood fiber and vessel element], and amounts of chemical components. In VD, CWT in wood fiber, and CL in wood fiber and vessel element, almost the same radial variation patterns were found in the three species. Relatively higher values in SWV, BD, and CS were found in N. lappaceum, suggesting that its wood can be used for construction lumber. On the other hand, S. malaccense and D. zibethinus had relatively thicker CWT in wood fiber, longer CL in wood fiber, and lower Klason lignin content. It is considered that the wood of these two species may be suitable for pulpwood