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1.
In Portugal, the oak pinhole borer Platypus cylindrus and its mycobiota have been associated with cork oak (Quercus suber) death, but no knowledge exists regarding the associated bacterial community. However, it is known that some bacteria are important for ambrosia beetle symbiosis and play a role in oak tree health. To explore the bacteria associated with this beetle and its host, with the ultimate goal of highlighting potential roles in oak decline, this study used a culture-dependent approach for strain isolation and phylogenetic identification using 16S rRNA gene sequencing and multilocus sequence analysis (MLSA). The bored galleries of different cork oak trees from a cork stand in Alentejo, together with the body and mycangia of adult beetles, were investigated. The samples revealed a diverse community comprising 500 isolates with 64 distinct types of bacterial colonies. Sixty-eight strains were selected for sequencing and used for phylogenetic analysis, 40 from wood galleries and 28 from beetles. Thirty-two genera of bacteria were identified, 18 of which were described for the first time within oak–beetle interactions. Major taxonomic groups were Actinobacteria in beetles and Enterobacterales in wood galleries. Although specific oak bacterial pathogens were not detected, a group of distinct strains detected in wood galleries, potentially belonging to a new Pectobacteriaceae species, were able to produce mild symptoms on cork oak plantlets. This study reports for the first time the biodiversity of culturable bacteria associated with the Q. suber–P. cylindrus interaction, their relevance to both organisms and the possible contribution to oak decline.  相似文献   
2.
为提高软木地板表面的物理性能,采用弹性漆对软木地板表面进行涂饰处理,研究不同弹性漆的涂漆量、油漆固化温度对软木地板表面耐磨、耐冲击性、表面色度学特性的影响。结果表明:与对照相比,软木地板表面漆膜具有优良的耐磨性、表面磨耗值随着弹性漆涂漆量的增加而降低,表面磨耗值为0.015 6~0.031 0 g/100 r;弹性漆对软木地板表面抗冲击改善幅度较大;油漆固化温度和涂漆量对软木地板表面颜色影响较小。  相似文献   
3.
介绍了软木细胞的形态特征,综述了国内外学者在软木细胞壁结构及化学组成方面的研究进展。软木细胞壁具有明显的层次结构,褶皱是软木细胞壁的一个主要特征,胞间连丝是跨越细胞壁之间透镜状通道。软木细胞壁主要化学成分有软木脂、木质素、多糖、抽提物和灰分,归纳总结了不同学者对各成分的测定结果以及各成分中单体的提取制备、分析鉴定结果,并提出软木细胞壁今后的研究方向。  相似文献   
4.
软木地板生产工艺研究   总被引:1,自引:0,他引:1  
通过对软木地板生产中的粉碎分选、施胶搅拌、热压、剖层和表面涂饰等关键工序的分析,总结出软木地板生产关键技术,并对软木工业发展提出了一些建议,旨在为软木设备选型、技术研究与开发提供参考。  相似文献   
5.
Host trees can modify their soil abiotic conditions through their leaf fall quality which in turn may influence the ectomycorrhizal (ECM) fungal community composition. We investigated this indirect interaction using a causal modelling approach. We identified ECM fungi on the roots of two coexisting oak species growing in two forests in southern Spain - Quercus suber (evergreen) and Quercus canariensis (winter deciduous)-using a PCR-based molecular method. We also analysed the leaf fall, litter and soil sampled beneath the tree canopies to determine the concentrations of key nutrients. The total mycorrhizal pool was comprised of 69 operational taxonomic units (OTUs). Tomentella and Russula were the most species-rich, frequent and abundant genera. ECM fungi with epigeous and resupinate fruiting bodies were found in 60% and 34% of the identified mycorrhizas, respectively. The calcium content of litter, which was significantly higher beneath the winter-deciduous oak species due to differences in leaf fall quality, was the most important variable for explaining ECM species distribution. The evaluation of alternative causal models by the d-sep method revealed that only those considering indirect leaf fall-mediated host effects statistically matched the observed covariation patterns between host, environment (litter, topsoil, subsoil) and fungal community variables.  相似文献   
6.
软木及其主要产品的耐候性研究   总被引:1,自引:0,他引:1  
采用紫外灯耐候试验箱模拟自然环境对软木原材料及其制品进行耐候性试验,通过对紫外灯耐候试验箱照射过的试件进行物理性能、力学性能的分析,对软木及其产品的耐候性进行客观评价。试验确定的试验参数为:辐照时间4和8h;黑暗时间4h;试验时间为80、160和240h。随着试验时间的增加,软木及其制品的密度、亨特白度、回弹率、断裂强度呈现下降趋势;压缩率呈现上升趋势。  相似文献   
7.
软木/龙须草纤维复合材料的研究   总被引:1,自引:1,他引:0  
为了降低软木材料的生产成本,将龙须草纤雏和软木粒子混合,进行了软木/龙须草纤维复合材料的开发研究.以复合材料的耐水性、抗拉强度、可压缩系教、回弹率等为指标,考察了龙须草纤维的比例、施胶量、热压温度和热压时间的影响.得出较佳的工艺条件为:龙须草纤维比例20%,施胶量8%,热压温度150℃,热压时间15 min.  相似文献   
8.
栓皮栎软木的微观构造   总被引:2,自引:0,他引:2  
栓皮栎(Quercus-variabilis)或栓皮槠(Q.suber)树皮部分的木栓层通常称为"软木",英文为cork或者phellogen,与通常所说的针叶材软木(softwood)不同.软木独特的细胞构造及其化学成分使其具有质轻、弹性好、隔热、隔音、隔水、防潮、阻燃、柔软、耐磨等优良特性,素有"软黄金"之称(郑志峰,2005).  相似文献   
9.
Modelling cork oak production in Portugal   总被引:1,自引:0,他引:1  
The layout of 32 permanent plots in the most important cork production regions of Portugal and the measurement of the most representative tree parameters were performed for statistically sound cork weight modelling. The establishment of cork weight equations is presented for the different cork oak study areas considered alone or grouped according to the most representative tree parameters. For the presented cork weight models was chosen independent variable the total stripping surface (artmax). For the selection criteria five statistic were used, including PRESS, APRESS and Mallows's statistic. The crossvalidation of the best classified models was performed and to discuss the importance of the “study area” factor, a regression analysis with “dummy” variables was performed.  相似文献   
10.
软木复合地板生产工艺及其发展前景   总被引:4,自引:1,他引:3  
本文介绍了软木复合地板这一地面铺装材料新产品的性能、结构特点和生产工艺并论述了在我国生产软木复合地板的可能性及发展前景  相似文献   
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