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1.
Wood samples of apitong (Dipterocarpus grandiflorua) and ilang-ilang (Ilang-Ilang C. dadloyi) and feces of termites [Cryptotermes brevis (Walker)] fed on these woods were collected from University of the Philippines, Los Baňos. Lignin of each sample was isolated by Björkman’s procedure. There was no significant difference in 1H nuclear magnetic resonance (NMR) spectra or in the methoxyl content between Björkman lignins from original woods and termite feces. Differences were detected in the contents of aliphatic and unconjugated phenolic hydroxyl groups, suggesting minor structural changes of lignin during digestion by termites. In addition, the ratio of syringyl to guaiacyl nuclei of Björkman lignin from termite feces determined by 1H NMR spectra was higher than those from the original woods. The molar ratio of syringyl to guaiacyl nuclei of termite feces was higher than those from the original woods as determined by alkaline nitrobenzene oxidation. These results suggest that the structural changes of lignin in the termite gut are due to the insignificant formation of C-C linkages in guaiacyl nuclei. It was concluded that there were minor changes in the structural features of lignin under mostly anaerobic conditions, in contrast to the significant changes that occur through biological modification under aerobic conditions. 相似文献
2.
Trochodendron aralioides Sieb. et Zucc. and Chloranthus glaber (Thunb.) Makino [Sarcandra globra (Thunb.) Nakai] belong to primitive angiosperms, and are characterized by the absence of vessels. Ephedra sinica Stapf, which is classified in the gymnosperms, contains vessel elements and fiber together with tracheids. Podocarpus macrophyllus (Thunb. Ex Murray) D. Don var. macrophyllus is reported to give a weak positive Mäule test, although it is classified as a gymnosperm. Podocarpus macrophyllus gave only vanillin on alkaline nitrobenzene oxidation, while E. sinica, T. aralioides, and C. glaber gave both vanillin and syringaldehyde. The molar ratio of syringyl to guaiacyl nuclei (S/V ratio) of C. glaber was significantly low (S/V = 0.08) in comparison with the value for T. aralioides (S/V = 1.56). The erythro form is the predominant diasteromeric form of β-O-4 intermonomer linkages of T. aralioides and E. sinica [molar ratio of erythro to threo forms (E/T ratio): 1.93 and 1.67, respectively]; however, P. macrophyllus and C. glaber lignins, of which S/V ratios were 0 and 0.08, gave approximately equal amounts of erythro and threo forms (E/T ratio: 1.01 and 1.14). Results from 1H NMR spectroscopy agree well with S/V ratios of alkaline nitrobenzene oxidation and E/T ratios of ozonation products. In conclusion differences in guaiacyl lignin and guaiacyl-syringyl lignin do not exactly reflect taxonomical differences, as reported in previous articles. It was found that guaiacyl-syringyl lignin is not necessarily linked to the presence of vessels. 相似文献
3.
Olga Alvarez Colom Isabel Barrachina Ildefonso Ayala Mingol M. Carmen Gonzalez Mas Pilar Moya Sanz Adriana Neske Alicia Bardon 《Journal of pest science》2008,81(2):85-89
From an Argentine collection of Annona cherimolia and a Bolivian collection of Annona montana (Annonaceae), the acetogenins, squamocin, molvizarin, itrabin, almuñequin, cherimolin-1, annonacin, annonacin-A, densicomacin-1, cis-annonacin-10-one and murihexocin-A, were obtained to study their toxicity against the cotton pest Oncopeltus fasciatus (Hemiptera: Lygaeidae). Topical ventral application of O. fasciatus nymphs with solutions of the mentioned acetogenins produced acute and delayed mortality. 相似文献
4.
Masatsugu Takada Harifara Rabemanolontsoa Eiji Minami Shiro Saka 《Journal of Wood Science》2018,64(6):802-809
To elucidate the decomposition behaviors of lignin from different taxonomic groups, five different lignocellulosics were treated with hot-compressed water (230 °C/10 MPa/15 min) to fractionate lignins into water-soluble portions, precipitates, and insoluble residues. The lignin-derived products in each fraction were characterized and compared. The delignification of monocotyledons [nipa palm (Nypa fruticans) frond, rice (Oryza sativa) straw, and corn (Zea mays) cob] was more extensive than that achieved for Japanese cedar (Cryptomeria japonica, gymnosperm) and Japanese beech (Fagus crenata, dicotyledon angiosperm). The water-soluble portions contained lignin monomers like coniferyl alcohol and phenolic acids, while the precipitates contained higher molecular weight lignin with high content of ether-type linkages. Lignin in the insoluble residues was rich in condensed-type structures. In all five lignocellulosics, ether-type linkages were preferentially cleaved, while condensed-type lignin showed resistance to hot-compressed water. In the monocotyledons, lignin–carbohydrate complexes were cleaved and gave lignins that had higher molecular weights than those eluted from the woods. These differences would facilitate the delignification in monocotyledons. Such information provides useful information for efficient utilization of various lignocellulosics. 相似文献
5.
Menandro N. Acda 《Journal of pest science》2008,81(2):109-113
Thiamethoxam (ACTARA® 25WG) was evaluated for its insecticidal activities against the bamboo powder post beetle Dinoderus minutus Fabricius (Coleoptera: Bostrichidae). The study showed that thiamethoxam had contact toxicity against D. minutus. Based on dose-mortality responses, LC50 values for thiamethoxam against D. minutus ranged from 1.74 to 7.94 μg ml?1. Laboratory and field exposure tests showed that thiamethoxam at concentration of atleast 10 μg ml?1 may have anti-oviposition or anti-feeding effects on D. minutus and can protect post harvest Bambusa vulgaris Schrad. culms against the infestation of this bamboo boring beetle. 相似文献
6.
Satoko Shimizu Pattaraporn Posoknistakul Takuya Akiyama Tomoya Yokoyama Yuji Matsumoto 《Journal of Wood Science》2018,64(5):664-674
The reaction products of an alkaline treatment of non-phenolic β-O-4-type lignin model compounds (C6–C2-type) consisting of p-hydroxyphenyl (H), guaiacyl (G), and/or syringyl (S) nuclei were identified and quantified. This was performed to examine how the type of H, G, or S nucleus affect the reaction product profiles. The major identified and quantified reaction products were phenol derivatives that were liberated from the aryl sides of the β-O-4 ether bonds of the lignin model compounds. Other products included derivatives of phenylethane-1,2-diol (glycol-type), benzaldehyde, and acetophenone, which originated from the alkyl sides of the β-O-4 ether bonds of the lignin model compounds. Although the type of aromatic nucleus of the aryl side of the β-O-4 ether bond of the lignin model compounds did not significantly affect the profile of the reaction products, the type of the alkyl side nucleus was influential. The glycol-type compound was the exclusive major reaction product when the S nucleus was on the alkyl side of the β-O-4 ether bond. On the other hand, when the H or G nucleus was present, a benzaldehyde derivative was the other major reaction product. 相似文献
7.
Taku Tsuyama Natsumi Shimada Taichi Motoda Yasuyuki Matsushita Yoshio Kijidani Kazuhiko Fukushima Ichiro Kamei 《Journal of Wood Science》2017,63(6):551-559
Bamboos are among the largest woody grasses and grow very rapidly. Although lignin is a crucial factor for the utilization of bamboo biomass, the lignification mechanism of bamboo shoots is poorly understood. We studied lignification in the bamboo Sinobambusa tootsik during culm development. Elongation growth began in May and ended in late-June, when the lignin content was approximately half that in mature culms. Thioacidolysis analysis indicated that p-hydroxyphenyl units in lignin formed even at late stages of lignification. The syringyl/guaiacyl ratio varied during culm development. Various lignin precursors were detected in developing culms by liquid chromatography–mass spectrometry. The ferulic acid content decreased from May to June, indicating that ferulic acid was utilized in early stages of cell wall formation. Monolignol glucosides were detected at early stages of lignification, whereas the contents of monolignols, coniferaldehyde, sinapaldehyde, p-coumaric acid, and ferulic acid peaked at later stages of lignification. Therefore, lignin precursors may be supplied differentially during the lignification process. In August, the rate of lignification decreased, although the contents of various lignin precursors peaked, implying that the rate-limiting step in the cessation of lignification in bamboo is transport or polymerization of lignin precursors, rather than their biosynthesis. 相似文献
8.
Biological and other alternative control methods were tested against the woolly beech aphid (Phyllaphis fagi). Field applications of mineral oil to the egg stage reduced initial aphid population by 75%, but only when the eggs were exposed to oil close to the time of hatching. Earlier oil treatments had no effect. Bioassays with the insect pathogenic fungus Lecanicillium lecanii (Verticillium lecanii) in the commercial formulation Vertalec® were conducted using different dosages, i.e. 1 × 106 ml?1 (recommended dosage) and 2 × 107 ml?1. Both nymphs and adults were susceptible to fungal infection at both dosages. The existence of a dense wax-covering in adult P. fagi had no protective effect against fungal infection. In bioassays where leaves were treated with the recommended dosage of Vertalec, there was no difference in mortality measured after 14 days between adult P. fagi with an intact wax-layer and adult P. fagi where the wax-layer had been removed. In semi-field trials with two L. lecanii treatments at the recommended dosage, the aphid population was reduced. There was no enhanced effect with the addition of an additive to the fungal suspension or from covering the plants with a polypropylene cover. The results reveal potential alternative control methods against P. fagi populations. However, adequate control with L. lecanii probably requires several treatments as opposed to the two that were tested in the present experiment. Furthermore, efficiency may depend on summer temperatures and humidity. 相似文献
9.
Haruna Aiso-Sanada Futoshi Ishiguri Denny Irawati Imam Wahyudi Shinso Yokota 《Journal of Wood Science》2018,64(6):872-879
This study investigated the anatomical and chemical characteristics of the reaction wood of a gymnpsperm species, Gnetum gnemon, and discussed on contributing factor for the type of reaction wood in this species. Cell morphology, microfibril angle (MFA) of the S2 layer and lignin distribution in secondary walls of tracheary elements, and lignin content were examined on three branches. Observations included no G-layer formation, significant decreases in vessel frequency, and altered MFA, and visible-light absorbance after lignin colour reactions in tracheid and fiber tracheid walls on the upper side in almost all samples. These results suggest that reaction wood in G. gnemon was similar to that in ‘tension-wood-like-reaction wood’ in angiosperms. On the other hand, reaction wood showed decrease in the lignin concentration in the fiber tracheid walls compared to the tracheid walls. In addition, the lignin in the tracheid and fiber tracheid walls was originally rich in syringyl units, suggesting that changes in the anatomical and chemical characteristics of secondary xylem due to reaction wood formation might relate to the ratio of the syringyl to guaiacyl units in lignin in the cell walls which function for mechanical support. 相似文献
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11.
Truffles, subterranean fruit-bodies of the ectomycorrhizal genus Tuber, are currently cultivated on host trees in plantations, both to offset declining wild production and to extend their geographic distribution. We report the effects of the potting medium and potting method components of two very different seedling production systems on the colonization of Quercus bicolor × Q. robur seedlings by T. aestivum (the Burgundy truffle). Seedlings grown in book planter containers using a peat-based medium were smaller yet much better colonized by T. aestivum than seedlings produced in RPM® (Root Production Method) containers using a ground bark-based RPM medium. In either container method, the peat-based medium supported development of more T. aestivum mycorrhizae than did the RPM medium. Seedlings grown in book planters developed significantly more root tips l?1 of medium than did seedlings grown in RPM containers. The optimum pH for T. aestivum mycorrhiza development in the peat-based medium is between 6.7 and 7.5. 相似文献
12.
Didi Tarmadi Tsuyoshi Yoshimura Yuki Tobimatsu Masaomi Yamamura Takuji Miyamoto Yasuyuki Miyagawa Toshiaki Umezawa 《Journal of Wood Science》2017,63(5):464-472
We investigated the physiological responses of a lower termite, Coptotermes formosanus, fed on various lignocelluloses and purified lignins (milled-wood lignins, MWLs) from Japanese cedar (softwood), Japanese beech (hardwood), and rice (grass). Termite survival, body mass, and the changes of the symbiotic protists in the hindgut of workers were observed for 4 weeks. The survival, body mass and presence of both Pseudotrichonympha grassii and Holomastigotoides hartmanni in the hindgut of workers fed on rice lignocellulose at the 4th week of observation were significantly lower than those of the workers fed on Japanese cedar and Japanese beech lignocellulose samples, whereas there was no significant difference in Spirotrichonympha leidyi among all the diets. The three purified MWLs, regardless of their structural differences, did not show any significant differences for the termites’ survival or body mass or the survival of all the three protists. The three MWL diets resulted in significantly lower termite survival compared to starvation, although these diets showed no significant effects on body mass or the protist profiles. Overall, lignins are hardly utilized as a nutrient source by C. formosanus workers and are even rather detrimental to termites when fed on solely. 相似文献
13.
Naoki Takata Shingo Sakamoto Nobutaka Mitsuda Toru Taniguchi 《Journal of Wood Science》2017,63(4):396-400
Wood biomass is one of the promising future materials for biofuels with no competing food uses. However, the higher cost to produce bioethanol from wood feedstocks is regarded as a priority issue. Genetic engineering techniques have been proposed to enhance the quality and quantity of wood materials to overcome the cost problem. Although many genetically engineered trees with applicable traits such as low lignin, a high syringyl to guaiacyl ratio and high cellulose content are generated, ectopic expression of an effector gene under a constitutive promoter can sometimes induce untoward side effects on plant growth and development. Our recent study demonstrated that AtNST3/SND1 promoter of Arabidopsis thaliana is a candidate tool for driving a potent activator to enhance wood biomass production in poplar without any growth retardation. However, the tissue- and cell-dependent activity of the promoter remains to be elucidated. In the present study, we generated transgenic poplar expressing AtNST3/SND1promoter::GUS to examine in detail the activity of the AtNST3/SND1 promoter. Histochemical analysis revealed that the promoter was predominantly active in secondary woody tissue. Our result indicates that the AtNST3/SND1 promoter is an option for expressing an effector gene to modify secondary cell wall components and wood biomass. 相似文献
14.
Thermoplastic processing of lignin is restricted by its high glass transition temperature (T g). In this study, lignin was modified with polyethylene glycol (PEG) during steam explosion to improve its thermoplastic properties, and the effects of steam explosion and PEG on the chemical structure and thermal properties of lignin were investigated. Structure characterization using Fourier transform infrared spectroscopy showed that hydroxyl and ether functional groups increased and the activity of lignin was improved by steam explosion. In addition, steam explosion treatment was more effective than heat treatment for promoting the reaction of PEG with lignin. Solid-state 13C NMR revealed that PEG was grafted onto lignin. The T g of raw lignin was 164.1 °C; after steam explosion, lignin exhibited more than one T gs. The T g of lignin was reduced when the steam explosion temperature increased and decreased further, to around 60 °C, when PEG was used to modify lignin. Therefore, this work provides an effective approach to reducing the high T g of lignin. 相似文献
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16.
Patrick Rousset Catherine Lapierre Brigitte Pollet Waldir Quirino Patrick Perre 《Annals of Forest Science》2009,66(1):110-110
17.
Xiaoxia Yang Jing Zhao Jian Zheng Pingsheng Leng Xiaolong Li Zenghui Hu Jianbin Liu Xin Meng 《林业研究》2016,27(2):273-281
Syringa is an important aromatic woody angiosperm that is widely planted in gardens. Its dry flowers are traditionally used to manufacture infusions and spices in China. In this study, the floral volatiles emitted from nine different Syringa species and varieties, viz. S. chinensis, S. p rotolaciniata, S. o blata, S. o blata var. giraldii, S. o blata var. plena, S. v ulgaris ‘Mrs Harry Bickle’, S. v ulgaris ‘Bright Centennial’, S. v ulgaris ‘White Spires’, and S. v ulgaris ‘President Lincoln’ were collected by the dynamic headspace technique, and then identified by automated thermal desorption–gas chromatography/mass spectrometry. There were significant differences in components and corresponding contents of floral scent emitted from the nine Syringa species and varieties. Among the detected components, β-ocimene exhibited the highest content, accounting for more than 70 % of the floral scent of S. p rotolaciniata, S. o blata var. giraldii, and S. v ulgaris ‘Bright Centennial’. A significant daytime variation of floral scent emitted from S. p ekinensis was recorded, especially for benzaldehyde, whose content first increased and then decreased. We studied the scent emitted from the in vitro flowers of S. v ulgaris ‘Pres Lincoln’ during the process of natural drying. Alcohol compounds were released in the greatest content, and the content of 2-ethyl-1-hexanol accounted for about 40 % of the total release amount. The results described the emission pattern and mechanisms of floral scent in Syringa. 相似文献
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19.
The naturally occurring Verticillium nonalfalfae shows promise for biocontrol of the highly invasive Tree of Heaven (Ailanthus altissima), but might also bear a risk for non-target tree species. In this study, we conducted inoculations on potted seedlings of A. altissima as well as on eight indigenous and two invasive tree species associated with Tree of Heaven in Austria. Although vascular discolourations developed in all inoculated tree species, V. nonalfalfae was reisolated from Ailanthus and eight of the ten non-target-species, whereas typical disease symptoms and mortality only occurred on A. altissima. Results confirmed high susceptibility (S) of A. altissima to V. nonalfalfae but indicated tolerance (T) of Acer campestre, Acer pseudoplatanus and Quercus robur, possible resistance (PR) of Fraxinus excelsior, Populus nigra, Tilia cordata, Ulmus laevis and Ulmus minor and resistance (R) of Fraxinus pennsylvanica and Robinia pseudoacacia to this potential biocontrol agent. Results from seedling inoculations were confirmed by cursory field observations in Ailanthus-inoculated forest stands, where admixed A. campestre, A. pseudoplatanus, F. excelsior, Populus alba, R. pseudoacacia and U. laevis canopy trees remained asymptomatic, while mortality was induced in Ailanthus. 相似文献
20.
We studied leaf litter fall, decomposition and nutrient release patterns of Shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf litter. Annual litterfall varied from 13.40 ± 2.56 t ha?1 a?1 for S. robusta to 11.03 ± 3.72 t ha?1 a?1 for T. grandis and the decay constant (k) of decomposed leaf litter was distinctly higher for T. grandis (2.70 ± 0.50 a?1) compared to S. robusta (2.41 ± 0.30 a?1). Biomass loss was positively correlated with the initial litter C, WSC, C/N and ash content in S. robusta and N, P and K concentration for T. grandis. Biomass was negatively correlated with lignin and L/N ratio for S. robusta and L, WSC, L/N and C/N ratio for T. grandis (P < 0.01). Nutrient use efficiency (NUE) and nutrient accumulation index (NAI) of S. robusta was higher than for T. grandis. The retranslocation of bioelements from senescent leaves ranked as P > N > K. Annual N, P and K input to soil through litterfall differed significantly between the two species in the following order: N>K>P. S. robusta was superior in terms of K and P return and T. grandis was superior in terms of N return. The two tree species showed a similar patterns of nutrient release (K > P > N) during decomposition of their leaf litter. Nutrients of N, K and P were the primary limiting nutrients returned to soil through litterfall with important roles in soil fertility and forest productivity. 相似文献