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Karen M. Barry Rie Mihara Noel W. Davies Tohru Mitsunaga Caroline L. Mohammed 《Journal of Wood Science》2005,51(6):615-621
The heartwood of Acacia mangium is vulnerable to heart rot and this is the first study to investigate the role of heartwood extractives in its susceptibility.
Acacia auriculiformis was compared with A. mangium because it is rarely associated with heart rot. The heartwood extracts of both species were dominated by three flavonoids
(2,3-trans-3,4′,7,8-tetrahydroxyflavanone, teracacidin, and 4′,7,8,-trihydroxyflavanone), which were purified and identified by nuclear
magnetic resonance spectroscopy. The latter compound has not been previously reported in A. mangium and evidence for melacacidin is also newly reported. The mass spectrometric (MS) behavior of these compounds is given, for
example teracacidin does not form molecular ions by either electrospray ionization or atmospheric-pressure chemical ionization.
The nature of Acacia tannins was compared to quebracho tannin (composed of profisetinidins) using oxidative cleavage to enable MS detection but
a negative reaction was obtained for both, which suggests the Acacia tannins may also be of the 5-deoxy proanthocyanidin type. The concentration of flavanones was less when A. mangium heartwood was decayed but the amount of proanthocyanidins was only slightly reduced and therefore these compounds may be
more resistant to degradation by heart rot fungi. We found that the total phenol content of A. auriculiformis was about fivefold that of A. mangium, and, while preliminary, this provides evidence for a role played by phenolic extractives in heart rot resistance of these
Acacia species. 相似文献
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The competition-density (C-D) effects for mean mass for tree, stem, branch and leaf were analyzed in Acacia auriculiformis stands. Mean tree mass-density and mean organ mass-density were well explained by the C-D equation of tree and the C-D equation of tree organ, respectively. An equation describing the relationship between mean leaf area u and density was formulated that fit the u-data well. The relationship between mean tree mass w and the ratio of each organ to mean tree mass (wo/ w) was examined. With increasing w, the stem mass ratio wS/w increased, whereas the branch mass ratio wB/w and the leaf mass ratio wL/w decreased. The yield difference between the lowest-density stand and the high-density stand became greater with stand growth. However, the yield of the mid-density stand was slightly lower than the yield of the high-density stand during the experimental period. To produce the most desirable combination of demanding individual-tree size and relative high stem yield, the mid-density is recommended as proper planting density for future management of A. auriculiformis stands. 相似文献
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用10~1000 mg/L稀土溶液对马占相思和大叶相思浸种24 h后的试验结果表明:适宜浓度的稀土溶液可促进马占相思和大叶相思种子内含物的转化,从而促进种子的萌发和幼苗生长,但同一稀土溶液对不同树种的适宜浸种浓度不同。马占相思以10 mg/L处理有利于提高种子发芽势并缩短发芽时间;大叶相思10~30 mg/L处理显著提高种子发芽率和发芽势,但没有显著缩短发芽时间。200 mg/L及以上浓度浸种对2种树种种子萌发有抑制作用。考虑指标多重比较差异及经济因素,10 mg/L处理较利于马占相思和大叶相思幼苗高和根系生长。 相似文献
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以台湾相思、银合欢和火棘幼苗为试验材料,人工模拟干旱胁迫环境,通过测定各树种幼苗叶片的生理指标,研究了干旱胁迫对这3种幼苗的影响,并用主成分法综合评定了各树种的抗旱性。结果表明,干旱胁迫期间3种幼苗的叶片组织含水量下降,复水处理后恢复到与对照相近水平;3种幼苗叶片的叶绿素含量上升,复水后下降;3种幼苗叶片的脯氨酸、可溶性蛋白、可溶性糖含量上升或上升后下降,复水后一般恢复到对照水平;台湾相思和火棘幼苗的叶片SOD活性显著上升后小幅波动,而银合欢的幼苗叶片SOD活性持续增加;台湾相思和火棘幼苗的叶片丙二醛含量逐渐上升,银合欢上升后波动。3种幼苗叶片的SOD活性和丙二醛含量复水后均下降。对生理指标进行主成分分析表明,3种幼苗的抗旱性为台湾相思>银合欢>火棘。 相似文献
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We conducted a study to find out if arbuscular mycorrhizal(AM) fungi(Acaulospora scrobiculata,Scutellospora calospora) and phosphate solubilizing bacteria(PSB, Paenibacillus polymyxa) inoculation either individually or in combinations can improve Acacia auriculiformis seedling growth, uptake of nutrients and quality in a phosphorus deficient tropical Alfisol. The seedlings were assessed for various growth and nutrient uptake parameters after 60 days of treatment. Inoculation with P.polymyxa stimulated mycorrhizal formation. Seedling height, stem girth, taproot length, number of leaves and leaf area, plant dry matter production, nodulation, and nodular dry weight were significantly higher for seedlings that were either dual inoculated or triple inoculated compared to individual inoculation of AM fungi or PSB, and uninoculated seedlings. Dual and triple application of AM fungi and PSB also significantly improved the nutrient contents of shoots and roots and nutrient uptake efficiencies. The calculated seedling quality indexes of the AM fungi and PSB inoculated seedling were 25–208% higher than uninoculated seedlings. These findings show that A.auriculiformis seedlings when dual inoculated or triple inoculated performed better than seedlings inoculated with the microbes individually and compared with uninoculated control seedlings. We conclude that bioinoculation is important for the production of high-quality A.auriculiformis seedlings in tree nurseries for planting in nutrient deficient soils. 相似文献
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Li Yanan Zhang Tengzi Zhou Yongbin Zou Xiaoming Yin You Li Hui Liu Liying Zhang Songzhu 《European Journal of Forest Research》2021,140(5):1039-1048
European Journal of Forest Research - Ectomycorrhizal fungi (EMF) can enhance drought resistance of host plants by increasing nutrient and water absorption. Calcium (Ca) plays a central role in... 相似文献
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工业和住宅污泥对大叶相思种子萌发以及幼苗生长参数的影响 总被引:2,自引:0,他引:2
在孟加拉国吉大港大学林业与环境科学院苗圃内,评价了污泥对大叶相思种子萌发以及幼苗生长的作用。播种前,将污泥与营养匮乏的自然林土壤按不同比率混合,分别在播种后的第1,2和3个月时,记录种子萌发情况和幼苗生长参数(枝条和根系的长度、直径、枝条的鲜重和干重、根和总的干物质量)。在播种前和幼苗采收后,分别测定各个处理的污泥-土壤混合物的理化参数(pH值、有机碳、氮、磷、钾),以及重金属含量(铬、镍、锰、镉、锌)。结果表明,与对照相比,污泥-森林土壤混合物中播种的种子萌发率和幼苗生长参数发生显著变化。土壤-污泥按2:1混合时,种子萌发率最高(90%),幼苗生长速率和生物量最大,有机碳和氮磷钾含量也最高。混有工业污泥的土壤中重金属含量要高于混有住宅污泥的土壤。在工业污泥土壤中,污泥-土壤按1:1混合时,重金属含量最高。据此推荐,在退化森林土壤中,土壤-污泥以2:1混合较适合大叶相思种子萌发和幼苗生长。 相似文献
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《Southern Forests》2013,75(2):103-113
Tree biomass plays an important role in sustainable management and in estimating forest carbon stocks. The objective of this study was to select the best model for measuring stem biomass of Acacia auriculiformis in the study area. Data from five hillocks and 120 individual trees from each hillock were used in this study. Twelve different forms of linear, power and exponential equations were compared in this study to select the best model. Two models (VI and XI) were selected based on R 2, adjusted R 2, the Akaike information criterion, F-statistics and the five assumptions of linear regression. Model VI was discarded based on the Durbin-Watson value of autocorrelation of the residuals, then the ARIMA (2, 0, 1) model was used to remove the autocorrelation from the model and the final bias-corrected model XI was derived. The model was validated with a test data set having the same range of DBH and stem height of the training data set on the basis of linear regression, Morisita's similarity index, and t-test for mean difference between predicted and expected biomass. A comparison between the best logarithmic and non-linear allometric model shows that the non-linear model produces systematic biases and overestimates stem biomass for larger trees. The overall results showed that the bias-corrected logarithmic model XI can be used efficiently for estimating stem biomass of A. auriculiformis in the northeastern region of Bangladesh. 相似文献
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Phi H. Hai Gunnar Jansson Björn Hannrup Chris Harwood Ha H. Thinh 《Annals of Forest Science》2009,66(6):611-611
u| li]? Genotypic variation in wood total and partial shrinkage, basic density and growth traits was estimated in 51÷2 year old Acacia auriculiformis trees in a clonal test. li]? In the tangential, radial and longitudinal directions, the mean values were 2.64%, 1.64% and 0.77% for partial shrinkage, and 5.92%, 3.23%, and 0.96% for total shrinkage, respectively. Total and partial transverse shrinkage were significantly greater in sapwood than in heartwood. li]? Clonal repeatability (H C 2 ) estimates for partial shrinkage were lower than those for total shrinkage, and heartwood shrinkages had lower H C 2 than those for sapwood. Estimates of H C 2 were from 0.32 to 0.38 for total transverse shrinkage, comparable to H C 2 for both total and partial volumetric shrinkages (0.40 and 0.32, respectively). However, H C 2 for longitudinal shrinkages, total and partial coefficients of anisotropy were only from 0.09 to 0.18. li]? The genotypic coefficients of variation of all shrinkage traits varied from 5.45% to 8.02%. Total shrinkage was strongly positively correlated with partial shrinkage in each dimension. Genotypic correlations were not significant between shrinkage and growth traits or density. Strong and significant correlations between transverse shrinkage in heartwood and sapwood (0.87) indicated that juvenile shrinkage is a good genetic indicator of this trait in older trees. Utilisation du retrait du bois dans l’amélioration de l’Acacia auriculiformis A. Cunn. ex Benth à croissance rapide au Vietnam. 相似文献
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New Forests - Drought is one of the most critical limiting environmental factors for plant survival and restoration in areas of rocky desertification in southwestern China. Here, we aimed to... 相似文献
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为了提高大叶相思幼苗在干热河谷地区造林的成活率,2008年在元江通过对其幼苗分别进行不同剂量的Pt菌剂、干旱胁迫和Pt菌剂+干旱胁迫处理,测定出圃幼苗的苗高、地径、高径比、生物量等形态指标和叶绿素、可溶性糖含量及SOD酶活性等生理指标,并比较其抗逆性,同时对不同培育措施出圃幼苗造林6个月时的成活率和生长状况进行测定与比较。结果表明:随着Pt菌剂的使用量增加,大叶相思出圃苗木的高径比和地上部分和地下部分生物量的比值逐渐降低,SOD酶活性和可溶性糖含量逐渐增加,因而出圃幼苗的抗逆性增强;干旱胁迫和Pt菌剂的作用效果可以叠加。Pt菌剂10 g+干旱胁迫大叶相思的处理效果最佳,成活率最高。 相似文献
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Ca^2+是植物必需的矿质元素之一,直接参与调节细胞内许多重要生理生化过程,同时Ca^2+作为细胞内重要的第二信使,在植物感受和转导外界刺激等方面起着重要的作用。本文就国内外有关植物在盐胁迫和干旱胁迫条件下细胞内Ca^2+水平的变化以及Ca^2+与植物抗盐、抗旱性的关系作一慨述,并提出和讨论了有关该领域有待进一步探讨的问题。 相似文献
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以13个3年生麻栎无性系为研究对象,采用盆栽试验方法,研究了在持续干旱胁迫条件下的麻栎无性系土壤水势、叶片水势光合速率和蒸腾速率变化规律及其关系。结果表明,随着干旱胁迫的加剧,13个麻栎无性系土壤水势呈现出不断下降的变化趋势,叶片水势的变化无一致规律,光合速率则先下降而后上升,蒸腾速率的变化规律不尽相同。在13个麻栎无性系中,2、4、5、7、9和16号无性系的蒸腾速率、叶片水势和光合速率具有相同规律,随着干旱胁迫的加剧先下降而后上升,具有较强的适应干旱逆境的能力。对不同干旱条件下无性系的蒸腾速率、土壤水势、叶片水势和光合速率的相关性分析发现,干旱胁迫7天时,蒸腾速率和光合速率达极显著正相关;干旱胁迫12天时,蒸腾速率和土壤水势间呈极显著负相关,光合速率与土壤水势呈显著负相关;干旱胁迫17天时,蒸腾速率与光合速率呈显著正相关。 相似文献
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干旱胁迫下佛甲草生理生化变化的研究 总被引:1,自引:0,他引:1
为了解佛甲草对干旱环境的适应能力,研究了干旱胁迫下佛甲草组织中MDA,脯氨酸,叶绿素含量及SOD和POD活性的变化。研究结果表明,在轻度干旱胁迫下,植物组织中SOD和POD活性呈上升趋势;在严重干旱胁迫下SOD和POD活性有所下降。MDA含量整体呈上升趋势。干旱处理使叶绿素含量呈现先上升后下降的趋势。脯氨酸含量呈现上升趋势,在严重干旱时,略有下降。 相似文献
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GAN Cai-xia WU Chu School of Horticulture Gardening Yangtze University Hubei Province Jingzhou P. R. China Institute of Vegetables Hubei Academy of Agricultural Sciences Wuhan P. R. China 《中国林学(英文版)》2009,(2)
When Cercis chinensis seedlings suffered from drought treatment,net photosynthetic rates had been significantly reduced at the end of the drought treatment. Compared with the control,the activities of acid invertases in roots had increased 5 and 11 days after drought treatment. Seventeen days after drought treatment,the activities of acid invertases in roots were significantly decreased,while activities of alkaline invertases in roots had also been significantly reduced. As the moisture in culture media dec... 相似文献