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181.
Emmer wheat (Triticum dicoccon Schrank, 2n = 4x = 28) consists in a hulled wheat; its cultivation has been drastically reduced during the last century as a consequence of its low yield. Recently, its agronomic and nutritive values, as well as the increase of popularity of organic agriculture, have led to a renewed interest making its cultivation economically viable in the marginal lands with an increase of the cultivated areas. In Italy, it mainly survives in few marginal lands of central and southern Italy, where local varieties, adapted to the natural environment from where they originate, are used; moreover, some selected lines have also been developed. In the present work, agro-morphological and qualitative traits, together with molecular analyses of 20 emmer accessions consisting of Italian landraces, breeding lines, and cultivars, were performed. The field experiments were conducted for two consecutive years (2001/2002–2002/2003) in two locations: Viterbo in central Italy, and Foggia in south Italy. The analyzed emmer wheat accessions showed a good amount of genetic variability for both evaluated agro-morphological and molecular traits. This study illustrates an increase in earliness, GY, TW, TKW, and YI going from landraces, breeding lines to cultivars, while the variability does not change proportionally.  相似文献   
182.
Heritage apple (Malus domestica Borkh. hybrids) and pear (Pyrus communis L. hybrid) trees grow in villages throughout Terceira Island, Azores, Portugal. Some of these pears have different names but similar morphology. The objective of this study was to determine synonymy, homology, and phylogeny of apples and pears from Terceira and to examine potential relationships of the island pears with standard apples and pears of Portuguese or American descent. Nine apple microsatellite markers were used to determine genetic relationships. Distance- and parsimony-based cluster analysis grouped these genotypes into separate apple and pear clades. The Terceira apples were divided into two clades: the maçā and the reineta-reinette. Among the 17 heritage apple genotypes, seven unique accessions were identified and four groups of synonyms, or possibly clones, were detected including: ‘Reineta Agosto’ and ‘Reineta Verde’ from Altares; ‘Reineta Castanha’ and ‘Reineta Verde Miuda’; ‘Maçā Pêra,’ ‘Maçā Calhau’, ‘Pêro Branco’ from Salga and from Terra-Chā and ‘Maçā Marmelo’; and the five genotypes ‘Maçā Sao Joao’, ‘Malápio Rosa’, ‘Maçā Gaspar’, ‘Maçā Branca’ and ‘Maçā Pato’. In addition, two homonyms were detected. ‘Pêro Vermelho’ from Terra Chā was a separate genotype from a tree from Doze Ribeiras of the same name, but Pêro Branco from Terra Chā appears to be a clone that can be distinguished by an additional allele at CH1F07a from a tree with that name from Salga. One pair of apple clones, ‘Reineta Agosto’ and ‘Reineta Verde’ from Altares appear to be derived from an unreduced gamete of ‘Golden Delicious.’ Another apple genotype ‘Maçā Acida’ could be a sibling of the ‘Maçā Pêra’ clonal group. Other tested standard apples from the US genebank were unrelated to Terceira genotypes. Of the seven heritage pears, five unique genotypes and one pair of synonyms were detected. ‘Pêra Papo Pintassilgo’ from Raminho and ‘Pêra Vermelha’ from the nursery of Serviço de Desenvolvimento Agario da Terceira (SDAT) were synonyms. ‘Passans du Portugal’ was related to ‘Pêra Cabaca’ but other standard pears from the US genebank were unrelated to Terceira genotypes. Future studies will include additional apple and pear cultivars from other Islands of the Azores and continental Portugal, and wild Asian species to further explore genetic relationships.  相似文献   
183.
184.

Purpose  

An in situ phytoremediation trial was developed in order to investigate the function of alfalfa during a 2-year bioremediation of an agricultural soil contaminated with polychlorinated biphenyls (PCBs). The study was conducted with the aim to better understand the application potential of PCB phytoremediation at field scale.  相似文献   
185.
This study examined the effects of contact with wood on the living human body using a physiological index and subjective evaluation. Consecutive blood pressure measurements were used as the physiological index, and sensory evaluation using the semantic differential (SD) method was used for subjective evaluation. Consideration was also given to cases in which materials were cooled and heated as well as kept at room temperature, to eliminate the effects of heat flux due to differences in thermal conductivity between wood and other materials. It was found that contact with wood produced coarse/natural sensations, with no associated increase in systolic blood pressure. Contact with cold wood created subjectively dangerous/uncomfortable but still coarse/natural sensations, also with no associated increase in blood pressure; therefore, there was no correspondence between subjective evaluation and physiological responses. Contact with aluminum kept at room temperature and cold acrylic plastic created flat/artificial and dangerous/uncomfortable sensations, with an associated significant increase in blood pressure; thus, there was a close correlation between subjective evaluation and physiological responses. It was therefore concluded that contact with wood, unlike artificial materials such as aluminum, induces no physiological stress even when kept at room temperature or cooled. Part of this report was presented at the 48th Annual Meeting of the Japan Wood Research Society in Shizuoka, April 1998  相似文献   
186.
Mountain closure, considered an effective and economic measure for natural restoration of degraded forest ecosystems, has been widely carried out in the karst region of southwest China. The aim of this study was to evaluate microbial aspects of soil quality after mountain closure by analyzing soil microbial biomass, basal respiration, metabolic quotient, and relationships with basic chemical properties in Guizhou Province, a karst region of the upper Yangtze River. Soil quality was considered poor from the low levels of microbial biomass carbon (MBC), nitrogen (MBN), and microbial quotient (MBC/total C and MBN/total N), but high metabolic quotient (qCO2). Soil pH, showing marked variation from 4.1 to 7.9 in this karst region, was proved to significantly affect soil microbial biomass and activity. Soil microbial biomass, microbial quotient, and soil basal respiration declined significantly with decreasing soil pH, while qCO2 showed an apparently increasing, but not statistically significant, trend. The changes in microbial biomass and activity following the change in soil pH could possibly be because of a change in soil microbial composition, and more detailed research is necessary. Compared with soil pH, soil organic matter content was another, more important, factor that directly restricted microbial growth because of the serious loss as a result of disturbance. As a practical application based on microbial aspects, introduction of some N-fixing tree species may be an active and effective measure to improve soil fertility and thus to accelerate restoration of the forest ecosystem in the karst region.  相似文献   
187.
In Japan, ammoniacal copper quaternary wood preservatives type-1 (ACQ-1), which contains copper and benzalkonium chloride as its active ingredients, is among the most widely used wood preservatives in the pressure treatment of wood. Benzalkonium chloride (BAC) in commercial ACQ-1 products mainly comprises C12 and C14 homologues. In the present study, the leaching characteristics of these BAC homologues were investigated using the heartwood and sapwood portions of Japanese cedar, Japanese larch, and Sakhalin fir treated with ACQ-1 and 1% monoethanolamine (MEA) solution containing equimolar amounts of homologues. Distilled water (DW) and artificial seawater (SW) were used as leaching media. Consequently, it was observed that the leaching rate of the C12 homologue tended to be higher than that of the C14 homologue in DW. The leaching of C12 homologues was accelerated by using SW, resulting in a significantly higher leaching rate than the C14 homologue using SW. It was thought that the difference in the hydrophobicities based on alkyl chain lengths resulted in these phenomena. However, when the heartwood portion of Japanese larch was treated with the homologues in MEA, the leaching rate of the C14 homologue was significantly higher than that of the C12 homologue.  相似文献   
188.
张征明  杜华  王伟宏  王清文 《林业研究》2010,21(1):59-62,I0002,I0003
探讨了氧化铁颜料对木纤维.高密度聚乙烯复合材耐老化性能的改善作用。采用四种常用的氧化铁颜料与木纤维、高密度聚乙烯和其他加工助剂干混,并用自行设计的双螺杆/单螺杆双阶挤出机组制造木塑复合材料。对该木塑复合材料进行人工加速紫外循环老化处理,用CIE1976L^*a^*b^*表色体系和ASTMD790标准分别对老化前后的材料进行测试,结果显示加入颜料以后木塑复合材料的抗弯弹性模量没有明显的变化,但是弯曲强度都有一定程度的提高。经过2000h人工加速紫外老化以后,不论是颜色要是力学性能都发生了明显的变化。铁红和铁黑着色的试样在整个老化过程中表现较好,颜料添加量约2.28%比较适宜。  相似文献   
189.
 Two kinds of bamboo vinegar from madake bamboo (Phyllostachys bambusoides) and moso bamboo (Phyllostachys pubescens) were prepared to analyze their components by gas chromatography (GC). The original vinegar, distilled vinegar, ether-extracted vinegar, and three fractions including acidic, neutral, and phenolic fractions separated from ether-extracted vinegar were diluted with distilled water 102 to 107 times. These diluted vinegar solutions were used to investigate the effect of bamboo vinegar on the germination and radicle growth of seed plants. High concentrations of all kinds of treated bamboo vinegars (e.g., 102 of original vinegar and 103 of ether-extracted vinegar) showed strong inhibition against germination of the seeds. However, an appropriate dilution of bamboo vinegar showed an obvious promotional effect on germination and radicle growth for the four kinds of tested seeds (lettuce, watercress, honewort, chrysanthemum). Received: December, 12, 2001 / Accepted: July 29, 2002 RID="*" ID="*" Part of this paper was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001  相似文献   
190.
The morphological, physical, and mechanical properties of the nonwood plant fiber bundles of ramie, pineapple, sansevieria, kenaf, abaca, sisal, and coconut fiber bundles were investigated. All fibers except those of coconut fiber had noncircular cross-sectional shapes. The crosssectional area of the fiber bundles was evaluated by an improved method using scanning electron microscope images. The coefficient factor defined as the ratio of the cross-sectional area determined by diameter measurement, to the cross-sectional area determined by image analysis was between 0.92 and 0.96 for all fibers. This indicated that the area determined by diameter measurement was available. The densities of the fiber bundles decreased with increasing diameters. The diameters of each fiber species had small variation of around 3.4%-9.8% within a specimen. The tensile strength and Young’s modulus of ramie, pineapple, and sansevieria fiber bundles showed excellent values in comparison with the other fibers. The tensile strength and Young’s modulus showed a decreasing trend with increasing diameter of fiber bundles.  相似文献   
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