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1.
俄罗斯主要采脂树种——欧洲赤松松脂的化学组成   总被引:2,自引:0,他引:2  
德国W.Lange在研究不同地区来源的欧洲赤松松脂的化学组成时,曾按△~3-蒈烯含量不同,将它们分成中欧和南欧地区二类。本文研究俄罗斯境内的欧洲赤松松脂的组成,发现它与同纬度的中欧地区欧洲赤松松脂一样,含有较高数量的△~3-蒈烯。同时发现,在中国境内的欧洲赤松的2个变种──樟子松和长白松松脂中△~3-蒈烯含量也随纬度不同而有明显差别。  相似文献   
2.
松属种间嫁接对松脂化学组成的影响   总被引:1,自引:0,他引:1  
通过对光松、萌芽松或展松与湿地松嫁接后松树的松脂化学组成的研究,探讨松属种间嫁接对松脂化学组成的影响。结果发现作为接穗的光松、萌芽松和展松的松脂化学特下基本上不变,不具有其砧木-湿地松松脂的特征。  相似文献   
3.
国外引种松树松脂化学组成的特征   总被引:8,自引:4,他引:8  
W.B.Critchfield和E.L.Little,Jr.将油松组松树分成6个亚组。本文采用GC、GC-MS方法对分属4个亚组的16种国外引种松树松脂化学组成的特征进行研究,发现每一个亚组的松脂各有其特点。马尾松、黄山松等国内松树树种与黑松、琉球松、同属一个亚组,其松脂的化学特征比较相似;而与湿地松、火炬松等另一亚组松脂则有较大区别,说明亚组的划分有利于松树的化学分类。不同地理变种的加勒比松松脂  相似文献   
4.
Developing sustainable extractive industries in otherwise intact tropical forest regions requires a sound understanding of the production potential of key resource populations. The oleoresin extracted from Copaifera trees is an economically important non-timber forest product harvested throughout the lowland Amazon basin. We studied oleoresin extraction from four species of Copaifera trees with known harvest histories within two contiguous extractive reserves in western Brazilian Amazonia. We conducted a large-scale experimental harvest of 179 previously unharvested Copaifera trees, in both seasonally flooded (várzea) and adjacent unflooded (terra firme) forests. The likelihood of trees yielding any oleoresin was principally determined by their species identity: C. multijuga was the only species to regularly yield oleoresin (70% of trees). Yield volumes varied both amongst species and forest types: C. multijuga (restricted to terra firme forest) had the highest mean yield of 505 ml, whilst C. guyanensis produced higher volumes of oleoresin in várzea (139 ml) than terra firme (15 ml) forest. Intraspecific differences were driven mainly by tree size. To assess extraction sustainability, we reharvested a sample of C. multijuga trees and compared the oleoresin production of 24 conspecific trees that had been initially harvested one year previously with that of 17 trees initially harvested three years previously. Reharvested trees produced just 35% of the oleoresin volume compared to that when originally drilled, but this response was not affected by the time interval between consecutive harvests. We demonstrate that, within a population of Copaifera, both morphological and environmental factors restrict total productivity; consideration of these factors should inform sustainable management practises. We additionally raise methodological considerations that may improve the comparability of studies.  相似文献   
5.
马尾松采脂量的相关因子分析   总被引:6,自引:0,他引:6  
根据6年来的马尾松收脂量,结合生态因子、树体因子、采脂间隔期、采脂负荷等因素进行分析,结果表明:马尾松产脂量与温度、树高、胸径等呈显著或极显著的相关关系,生态因子中以气温对马尾松产脂量的影响最大,树体因子中以树龄的影响最大,降雨、土壤、地形等因子对采脂量也有影响,这些因子对马尾松产脂量的影响作用是综合的。  相似文献   
6.
流胶法在长岛县防治松材线虫病中的应用   总被引:1,自引:0,他引:1  
长岛县是我国北方松材线虫病的唯一疫区。 1999年用流胶法对长岛疫区内约 4 0 0多hm2 的松林内的感染松材线虫黑松病树进行早期诊断 ,结果表明低温对流胶法影响很大。在约 6 0 0 0 0 0株松树中 ,发现 935株松树流胶异常 ,从这些松树中取样经分离镜检发现 182株松树带有松材线虫 ,伐除这 182株松材线虫病树后 ,当年松材线虫病树死亡率减少 97%。对流胶法在生产上的应用进行了讨论。  相似文献   
7.
8.
秘鲁的松树资源及其松脂化学组成   总被引:6,自引:2,他引:4  
秘鲁具有丰富的松树资源,主要树种有展松,辐射松,粗糙枝松和粉枝五针松等。采用DB-5毛细管柱对这些树种的松脂进行分析,并用GC-MS鉴定。同时,采用QF-1毛细管柱将松脂中长叶松酸和左旋海松酸加以分离。  相似文献   
9.
Natural oleoresins rich in lycopene were obtained from two varieties of tomato (Zedona and Gironda) and their nutraceutical potential (antioxidant and antimutagenic capacity) was evaluated. Both oleoresins had a high content of lycopene, 58.33 ± 1.67 mg/g (Zedona) and 63.97 ± 0.80 mg/g (Gironda). The antioxidant activity (AA) of the oleoresins by β-carotene method were 56.4–74.5% (Zedona) and 51–72.8% (Gironda), while when using the free radical stable 2,2-diphenyl-picryl-hydrazyl (DPPH) method, the antiradical activity (ARA) was determined to be 18.2–32.7% (Zedona) and 16.6–26.7% (Gironda) for the concentrations tested that of 200–400 μM equivalents of lycopene. The antimutagenic activity of the oleoresins was tested against aflatoxin B1 (AFB1) using the microsuspension assay, both varieties had a very high antimutagenic potential against AFB1 (60–66%).These results suggest the NCRT can be taken advantage to obtaining rich oleoresin in lycopene with a nutraceutical value.  相似文献   
10.
 研究分析了湿地松20个抗病无性系和14个易感株针叶中的松脂含量,结果表明抗病湿地松针叶中的松脂含量为7.17%,明显比易感株含量5.46%高。顶冠针叶的松脂含量与侧枝针叶的含量基本相近。对9个抗病无性系和4个易感株针叶挥发油中的单萜和倍半萜研究表明,湿地松针叶中的单萜和倍半萜的种类较多,不同无性系(或单株)间高含量单萜和倍半萜种类较稳定,某些低含单萜组分与抗病性之间存在着一定的联系。抗病无性系针叶中都缺乏在感病针叶中普遍存在的异龙脑和香草醇。  相似文献   
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