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省藤属( Calamus L .) 属棕榈科(Palmae ) 省藤亚科(Calamoideae) , 是棕榈科中最大的属, 约有370种。中国是其天然分布的北缘, 共有37 种26 变种, 种数约占世界的10% , 有西南和东南两大分布中心;省藤属的天然分布地域性较强, 各地区特有种比例较高; 在区系上, 西南分布中心和中南半岛西部、南亚的省藤区系都有较强的联系, 东南分布中心与中南半岛东部的联系更为紧密。 相似文献
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Ramesha BT Ravikanth G Nageswara Rao M Ganeshaiah KN Uma Shaanker R 《Journal of genetics》2007,86(1):9-18
Given the increasing anthropogenic pressures on forests, the various protected areas—national parks, sanctuaries, and biosphere
reserves—serve as the last footholds for conserving biological diversity. However, because protected areas are often targeted
for the conservation of selected species, particularly charismatic animals, concerns have been raised about their effectiveness
in conserving nontarget taxa and their genetic resources. In this paper, we evaluate whether protected areas can serve as
refugia for genetic resources of economically important plants that are threatened due to extraction pressures. We examine
the population structure and genetic diversity of an economically important rattan, Calamus thwaitesii, in the core, buffer and peripheral regions of three protected areas in the central Western Ghats, southern India. Our results
indicate that in all the three protected areas, the core and buffer regions maintain a better population structure, as well
as higher genetic diversity, than the peripheral regions of the protected area. Thus, despite the escalating pressures of
extraction, the protected areas are effective in conserving the genetic resources of rattan. These results underscore the
importance of protected areas in conservation of nontarget species and emphasize the need to further strengthen the protected-area
network to offer refugia for economically important plant species. 相似文献
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对棕榈科(Palmae)省藤亚科(Calamoideae)省藤族(Calameae)省藤属(Calamus)8种4变种、钩叶藤属(Plectocomia)1种、黄藤属(Daemonorops)1种、蛇皮果属(Salacca)2种共4个属16种植物的花粉进行了光镜和扫描电镜观察。省藤属植物的花粉均为两沟型花粉,外壁纹饰为网状、穿孔或小凹穴等类型;黄藤属的黄藤(Daemonorops matgaritae)花粉为近环沟型,外壁纹饰为颗粒状,其萌发孔特征与以前报道不一致。钩叶藤属的钩叶藤(Plectocomia kerrana)花粉为两沟型,外壁纹饰为网状。蛇皮果属的滇西蛇皮果(Salacca secunda)花粉的萌发孔为2沟,外壁纹饰为稀疏的穿孔或者小孔穴,而蛇皮果(S.zal-acca)花粉萌发孔为近环沟型,外壁纹饰为刺状突起,刺之间为密集的小穿孔。研究表明,花粉特征可以反映省藤属内的种间差异,支持褐鳞省藤(Calamus balansaeanus var.castaneolepis)、滇缅省藤(C.erectus var.birmanicus)及长穗省藤(C.palustrisvar.longistachys)作为变种,支持勐腊鞭藤(C.karinensis)作为种的等级地位;另外花粉特征对于探索省藤属和其他属的亲缘关系具有重要的参考价值。 相似文献
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国产省藤属植物的叶表皮形态学 总被引:1,自引:0,他引:1
对国产省藤属(Calamus L.)植物17种2变种的叶表皮进行光学显微镜观察,除单叶省藤(C.simplicifolius)、短叶省藤(C.egregiw)和白藤(C.tetradactylus)外,其它种均为首次报道。省藤属植物的叶表皮形态较为一致,气孔器为轮列4细胞型(tetracytic,或称四轮列型),即有4个副卫细胞,其中2个为侧副卫细胞,2个为端副卫细胞;表皮细胞为长方形,纵向排列。表皮毛有3种类型:多细胞排成单列的单毛(人喙省藤C.macrorrhynchus)、多细胞排成2-3列的单毛(毛鳞省藤ethysanolepis等)、多细胞分枝毛(白藤等)。表皮细胞的长度和宽度特征、细胞壁的厚薄及波纹的深浅和形状、端副卫细胞的长短等细微特征在种问存在差异,可以区分种类。叶表皮结构还反映了种问的亲缘关系。因此,叶表皮特征对于省藤属种类的划分和亲缘关系的确定有较大的分类学意义。 相似文献
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钩叶藤属和省藤属导管分子的比较研究 总被引:6,自引:0,他引:6
本文描述3种钩叶藤属(Plectocomia)植物茎的后生木质部导管分子,并与省藤属(Calamus)比较分析。钩叶藤属的导管分子大部分具单穿孔板.类似省藤属,但具复穿孔板导管分子的比量和横隔数目以及导管分子长度均比省藤属大.讨论了导管分子特化同两属天然分布植被区的关系。 相似文献
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