草果果实中的酚性成分

从草果( Amomum tsao-ko) 果实的甲醇提取物中分离得到了9 个酚性化合物, 其中一个为新的糖基被酰化的酚性配糖体。用1D, 2D NMR 和MS 等现代波谱学方法鉴定为2-甲氧基-1 , 4-二苯酚-1-O - [6- O -(3-甲氧基-4-羟基苯甲酰基) ]-β-D-吡喃葡萄糖苷(1) 。8 个已知化合物分别为3′, 5′-二-C-β-D-吡喃葡萄糖基根皮素( 2)、芦丁(3) 、槲皮素-3- O-β-D-吡喃葡萄糖苷(4 ) 、邻苯三酚( 5 )、邻苯二酚( 6) 、对羟基苯甲酸( 7)、原儿茶酸(8) 和香草酸(9) 。化合物2 , 3 , 5 , 7～9 均为首次从草果果实中分离得到。     

砂仁中化学成分及其药理作用的研究进展

砂仁中的主要成分为乙酸龙脑酯、樟脑、龙脑等挥发性成分,另外非挥发性成分主要有多糖、黄酮苷类、有机酸类以及无机成分等。其药理作用研究大多集中在挥发油部分,目前发现砂仁的药理作用主要有胃肠保护功能、抗炎、镇痛、止泻、降血糖等。砂仁中成分的种类、含量受到基源、产地、部位等众多因素的影响。我们通过文献研究发现:阳春砂中含量最高的挥发性成分为乙酸龙脑酯,而海南砂、绿壳砂中含量最高的挥发性成分为樟脑。此外,广东阳春所产阳春砂主要挥发油成分含量较其他地方高,验证了阳春为阳春砂的道地产区,而西双版纳所产绿壳砂的主要挥发性成分含量最高,说明了西双版纳所产绿壳砂质量较优。本综述的分析总结为中药砂仁的进一步开发和利用奠定了理论基础。     

橡胶与砂仁间作小气候特点初探

橡胶与砂仁间作小气候特点初探周再知,郑海水,杨曾奖,尹光天（中国林业科学院热带林业研究所,广州５１０５２０）ＲｅｓｅａｒｃｈｏｎＭｉｃｒｏｃｌｉｍａｔｉｃＣｈａｒａｃｔｅｒｉｓｔｉｃｉｎＰｌａｎｔａｔｉｏｎｏｆＲｕｂｂｅｒＩｎｔｅｒｃｒｏｐｐｅｄｗｉ...     

Genome size variations within Dasypyrum villosum: correlations with chromosomal traits, environmental factors and plant phenotypic characteristics and behaviour in reproduction

 Feulgen/DNA cytophotometric determinations carried out in the root meristem of seedlings showed that substantial quantitative alterations in the nuclear genome are present between and within 15 natural populations of Dasypyrum villosum in Italy. When the most variant values are considered, there is a 17.6% difference between the mean genome size of the populations, and a 66.2% difference between the genome size of individual plants within a population. A highly significant, positive correlation was found to exist between the genome size of D. villosum plants and the altitude of their stations, and differences in DNA contents between individual plants were greater in populations from mountain sites. Karyological analyses showed all chromosome pairs to differ largely in size between plants with differing DNA contents. A highly significant, positive correlation was found to exist between genome size and both the length of the chromosome complement at metaphase and the length and arm ratio of pair VII. Significant correlations were also found between DNA content and certain phenotypic characteristics of the plants. The mean genome size of the populations was negatively correlated with the mean leaf length and width. In contrast, the genome size of individual plants was positively correlated with the weight of the seed from which they originated and their flowering interval. A large range of genome sizes was found in the half-sib progeny of a plant having a relatively large genome. In contrast, in the half-sib progeny of a plant having a small genome, the genome sizes of the individual plants were less divergent and similar to that of the mother plant. All siblings from crosses between plants with differing genome sizes had similar DNA contents, which were intermediate between those of the parental plants, even if closer to the DNA content of the parent plant having the smaller genome size. Size polymorphism within pairs was never observed in plants obtained from these crosses or in half-sibs whose genome size differed from that of the mother plant. The intraspecific alterations observed in the nuclear genome and their effects on plant development and phenotype are briefly discussed as evolutionary factors which allow D. villosum populations to withstand different environmental conditions as well as the variability of conditions in a given environment. Received: 6 October 1997 / Accepted: 28 October 1997     

西双版纳热带雨林中砂仁种植的可持续性分析

从生态效益和经济效益方面对在热带雨林中砂仁的种植经营模式进行了分析。结果表明,种植砂仁后,热带雨林中的植物多样性、凋落物量和土壤肥力比同类型的原始林都有不同程度的下降,营养元素在土层中的分布也有所改变;由于不合理的经营管理方式,在种植砂仁7－8年后,其经济效益呈明显下降趋势,表明林下砂仁的种植方式是不可持续性的。据此,提出了模式的改进设想,以达到生态效益、经济效益和社会效益相统一,实现热带雨林的可持续利用。     

砂仁种植对热带雨林植物多样性的影响探讨

通过对各种不同状况的林下种植砂仁的热带雨林片断与同样类型的原始热带雨林的比较研究 ,探讨了砂仁种植对热带雨林植物多样性各个方面的影响。砂仁种植必须大量清除小树、林下幼树、灌木层植物 ,致使种植了砂仁的热带雨林片断的乔木下层及几乎整个的幼树、灌木层遭严重破坏 ,物种和个体大量流失 ,群落结构变得非常不稳定。由于热带雨林的更新主要依赖于其林下层的幼苗库 ,林下层的幼树、苗库被清除或破坏 ,热带雨林就难以自我更新 ,故林下种植砂仁的更大的潜在危害是使得热带雨林不能自我更新。种植了砂仁的热带雨林片断 ,物种和个体数的减少或流失 ,主要是直接的人为清除的结果 ,清除强度大 ,种类和个体减少就多。热带雨林下砂仁种植后 ,那些在原乔木层中占多数的只有 1～ 2个个体的脆弱种类 (种群 )将首先消失     

阳春砂有性生殖特性的研究进展(综述)

阳春砂是我国珍稀濒危的药用植物,以其果实入药。由于阳春砂柱头高于花药,自然传粉结实率低,严重制约了果实产量。为揭示阳春砂果实形成的基础,探讨提高阳春砂产量的对应策略,本文就阳春砂的形态特征、生态习性、花粉发育、胚囊发育及开花、传粉、受精等有性生殖研究状况进行综述。     

砂仁光合作用的CO2扩散限制与气孔限制分析

目前常用从气体交换参数计算的胞间CO₂浓度(C_i)来计算气孔限制值(L_s),但由于胁迫情况下计算的C_i偏高常导致结果不准确。该文引入扩散限制分析概念,以砂仁为例介绍了一种不需 C_i的计算扩散限制值(L_d)的新方法。同时通过叶绿素荧光参数间接估算受干旱胁迫植株的C_i(用C_i'表示)计算气孔限制值(L_s')。采用这3种方法分析了生长在100%和40%土壤相对湿度(RSM)下的砂仁(Amomum villosum)净光合速率的限制因素。结果表明两种水分状况下砂仁午后净光合速率的限制因素不同。100%RSM下,午后砂仁L_s没有升高,说明光合作用气孔限制并未增强;午后其L_d升高表明光合作用的CO₂扩散限制增强,这主要是由叶肉阻力相对增大所致。40%RSM下,午后砂仁L_s'升高比L_d升高明显,说明气孔阻力在所有扩散阻力中占主导作用,是限制净光合速率的主要原因;而其 L_s午后并未升高,暗示传统的气孔限制分析会得出非气孔限制的错误结论。C_i'低于C_i,说明干旱胁迫时传统的气体交换方法高估了C_i。上述结果都证明水分胁迫情况下传统方法不可靠,该文介绍的两种新方法比较准确可靠,同时使用两种新方法还可定性推测叶肉阻力的变化方向。     

太白杜鹃一新变种

本变种与原变种var.purdomii的区别在于叶片较大,长4～11cm,宽2～55cm,上面疏生淡黄色长柔毛,边缘密生青白色和淡黄色缘毛,柔毛和缘毛易脱落;叶柄较长(长1～3cm);总花梗较长(长达18cm)。河南:嵩县,白云山国家森林公园,玉皇顶,海拔2100m,1993年7月4日,张益民、吴立宏93088(模式标本Typus存于河南农业大学植物标本室;同号模式标本存于中国科学院昆明植物研究所);内乡,宝天曼国家自然保护区,扫帚场,海拔1600m,1989年7月28日,张益民、温德臣89006。根据调查,本新变种常生于山之阴坡和湿度较大的地方。叶普遍较大,革质化程度稍低。生长状态叶上…