scholarly journals Visualization and Localization of Submicron-Sized Ammonium Sulfate Particles on Needles of Japanese Larch (Larix kaempferi) and Japanese Cedar (Cryptomeria japonica) and Leaves of Japanese Beech (Fagus crenata) and Japanese Chinquapin (Castanopsis sieboldii) after Artificial Exposure

Forests ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 1151
Author(s):  
Kenichi Yamane ◽  
Satoshi Nakaba ◽  
Masahiro Yamaguchi ◽  
Katsushi Kuroda ◽  
Yuzou Sano ◽  
...  

We applied a method combining field-emission scanning electron microscopy (FE-SEM) with energy dispersive X-ray spectrometry (EDX) to visualize the deposition and localization of the submicron-sized ammonium sulfate (AS) particles. The AS particles emitted from an aerosol generator in the laboratory were spherical in shape and individually deposited without aggregation on the surface of a silicon substrate. We determined the AS particles on the surfaces of the needles of Japanese larch (Larix kaempferi) and Japanese cedar (Cryptomeria japonica), and the leaves of Japanese beech (Fagus crenata) and Japanese chinquapin (Castanopsis sieboldii), using EDX. The particles were deposited on either the adaxial or abaxial side of the leaves and needles. The AS particles deposited on the surfaces of the leaves and needles did not aggregate, and they were deposited on the surfaces of the leaves and needles in the same manner, regardless of leaf structure. These results, using a new method, highlight the early stages of the deposition and localization of submicron-sized AS particles on the surfaces of the leaves and needles of forest trees.

Holzforschung ◽  
2011 ◽  
Vol 65 (5) ◽  
Author(s):  
Natthanon Phaiboonsilpa ◽  
Shiro Saka

Abstract Effect of acetic acid (AcOH) addition on chemical conversion of Japanese beech (Fagus crenata), as a hardwood, and Japanese cedar (Cryptomeria japonica), as a softwood, was investigated in the course of treatment in a semi-flow reactor with hot-compressed water (H-CW). One-step treatment of Japanese beech was preliminarily performed to examine the effect of AcOH concentrations on the decomposition behavior at 150–290°C/10 MPa/30 min. Based on the obtained results, two-step semi-flow H-CW treatment with 1 wt% AcOH at 210°C/10 MPa/15 min (1st stage) and 260°C/10 MPa/15 min (2nd stage) was thus selected as the most appropriate treatment and a comparative study of the two woods was accordingly conducted. The differences in decomposition behavior observed between the two woods clearly proved that the addition of AcOH played an important role in enhancing the hydrolysis and decomposition of cell wall components in Japanese cedar due to the lesser amount of acetyl residue in softwood hemicelluloses and its lignin structure.


2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Jiawei Wang ◽  
Eiji Minami ◽  
Mohd Asmadi ◽  
Haruo Kawamoto

AbstractThe thermal degradation reactivities of cellulose and hemicellulose are substantially different in Japanese cedar (Cryptomeria japonica, a softwood) and Japanese beech (Fagus crenata, a hardwood). Uronic acid and its salts act as acid and base catalysts, respectively, and their specific placement in the cell walls has been considered a factor that influences degradation reactivity. In this study, the role of lignin in degradation reactivity was investigated using holocellulose prepared from cedar and beech woods. The thermal degradation reactivities of cellulose and hemicellulose in holocellulose were evaluated according to the recovery of hydrolyzable sugars from heat-treated samples and compared with those of wood samples. Results show that the reactivities of xylan and glucomannan in both woods became similar to those of the corresponding isolated samples when lignin was removed. By contrast, the cellulose in both woods became more reactive when lignin was removed, and the degradation could be separated into two modes depending on the reactivity. These results were analyzed in terms of the effect of lignin on the matrix of cell walls and the interaction between the matrix and surface molecules of cellulose microfibrils. Differential thermogravimetric curves of the holocellulose samples were obtained and explained in terms of the degradation of hemicellulose and cellulose. The reported findings will provide insights into the research fields of wood pyrolysis and cell wall ultrastructures.


Forests ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 884
Author(s):  
Shufen Chen ◽  
Wataru Ishizuka ◽  
Toshihiko Hara ◽  
Susumu Goto

Research Highlights: The complete chloroplast genome for eight individuals of Japanese larch, including from the isolated population at the northern limit of the range (Manokami larch), revealed that Japanese larch forms a monophyletic group, within which Manokami larch can be phylogenetically placed in Japanese larch. We detected intraspecific variation for possible candidate cpDNA markers in Japanese larch. Background and Objectives: The natural distribution of Japanese larch is limited to the mountainous range in the central part of Honshu Island, Japan, with an isolated northern limit population (Manokami larch). In this study, we determined the phylogenetic position of Manokami larch within Japanese larch, characterized the chloroplast genome of Japanese larch, detected intraspecific variation, and determined candidate cpDNA markers. Materials and Methods: The complete genome sequence was determined for eight individuals, including Manokami larch, in this study. The genetic position of the northern limit population was evaluated using phylogenetic analysis. The chloroplast genome of Japanese larch was characterized by comparison with eight individuals. Furthermore, intraspecific variations were extracted to find candidate cpDNA markers. Results: The phylogenetic tree showed that Japanese larch forms a monophyletic group, within which Manokami larch can be phylogenetically placed, based on the complete chloroplast genome, with a bootstrap value of 100%. The value of nucleotide diversity (π) was calculated at 0.00004, based on SNP sites for Japanese larch, suggesting that sequences had low variation. However, we found three hyper-polymorphic regions within the cpDNA. Finally, we detected 31 intraspecific variations, including 19 single nucleotide polymorphisms, 8 simple sequence repeats, and 4 insertions or deletions. Conclusions: Using a distant genotype in a northern limit population (Manokami larch), we detected sufficient intraspecific variation for the possible candidates of cpDNA markers in Japanese larch.


Forests ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 524
Author(s):  
Junhua Xu ◽  
Shuangbao Zhang ◽  
Guofang Wu ◽  
Yingchun Gong ◽  
Haiqing Ren

With the increasing popularity of cross-laminated timber (CLT) constructions around the world, there have been attempts to produce CLT using local wood species in different countries, such as Japanese larch (Larix kaempferi (Lamb.) Carr.) in China. Thus, the need to investigate the connection performance also increases to support the design and construction of CLT buildings using local wood species. In this study, the withdrawal properties of three different types of self-tapping screws (STS), with a diameter of 6 mm, 8 mm, and 11 mm, were tested with Japanese larch CLT. The results revealed that the withdrawal strength of STS increased with increasing density and effective length, but decreased with an increasing diameter. With a density increment of 0.05 g/cm3, the withdrawal strength increased by an average of 9.4%. With an effective length increment of 24 mm, the withdrawal strength increased by an average of 1.4%. An empirical regression model was adopted to predict the withdrawal strength of Japanese larch CLT based on the results, which can be used for potential engineering design of CLT connections using STS.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yoshihiko Nanasato ◽  
Masafumi Mikami ◽  
Norihiro Futamura ◽  
Masaki Endo ◽  
Mitsuru Nishiguchi ◽  
...  

AbstractCryptomeria japonica (Japanese cedar or sugi) is one of the most important coniferous tree species in Japan and breeding programs for this species have been launched since 1950s. Genome editing technology can be used to shorten the breeding period. In this study, we performed targeted mutagenesis using the CRISPR/Cas9 system in C. japonica. First, the CRISPR/Cas9 system was tested using green fluorescent protein (GFP)-expressing transgenic embryogenic tissue lines. Knock-out efficiency of GFP ranged from 3.1 to 41.4% depending on U6 promoters and target sequences. The GFP knock-out region was mottled in many lines, indicating genome editing in individual cells. However, in 101 of 102 mutated individuals (> 99%) from 6 GFP knock-out lines, embryos had a single mutation pattern. Next, we knocked out the endogenous C. japonica magnesium chelatase subunit I (CjChlI) gene using two guide RNA targets. Green, pale green, and albino phenotypes were obtained in the gene-edited cell lines. Sequence analysis revealed random deletions, insertions, and replacements in the target region. Thus, targeted mutagenesis using the CRISPR/Cas9 system can be used to modify the C. japonica genome.


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