Phytochemical study on the leaves of Wollemia nobilis

In this work, a phytochemical study performed on the leaves of the rare species, Wollemia nobilis W.G. Jones, K.D. Hill & J.M. Allen, is reported. By means of classical column chromatography and NMR Spectroscopy and Mass Spectrometry, nine compounds were evidenced. These were: pheophorbide a (1), isocupressic acid (2), acetyl-isocupressic acid (3), sandaracopimaric acid (4), agathic acid (5), 7–4′-4‴-tri-O-methyl-agathisflavone (6), 7–4′-7″-4‴-tetra-O-methyl-agathisflavone (7), caffeic acid (8) and shikimic acid (9). Compared to our previous phytochemical analysis on the male cones, some further compounds were identified i.e. compounds 1, 5, 6, 7 and 8. This confirmed the previous chemotaxonomic considerations of the species but also added new ones which were discussed within the text. In addition, a possible different accumulation of secondary metabolites in the tissues and organs of this plant was even noticed.     

深圳福田两种红树林植物叶片分解研究

利用分解袋法研究两种红树林植物(秋茄、桐花)叶片在野外实地分解过程中的干物质和有机C、N、P变化情况.结果表明,秋茄叶片野外分解的速度要比桐花叶片快得多,初始非灰分物质干重(AFDW)损失一半所需的时间秋茄为12d,桐花35d左右.分解开始后,两种叶片的N含量均迅速上升,到达峰值后逐渐下降;而P含量则先略为下降,之后慢慢回升;叶片有机C含量则始终保持在相对较为稳定的水平上.试验的结果还表明,桐花叶片在红树林系统内沿潮汐梯度的不同滩面位置上分解时,各地点的分解速率间无显著差异.     

Viburnum tinus L.: Investigation on its spontaneous emission at different phenological stages

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Preliminary results of a fertilization-irrigation experiment in a Quercus ilex L. forest in relation to leaves and twigs characteristics

A multifactorial ANOVA experiment was designed for a Quercus ilex forest in the Prades mountains in Tarragona (NE Spain). The purpose of this study was to clarify the relative importance of water, nitrogen and phosphorus as factors controlling primary production.Eight plots comprising all possible combinations of the three factors (including a control) were laid out in three replicate blocks. Fertilizers were applied to the appropriate treatments in March 1989 with a dosage of 125 kg of P/ha and 250 kg N/ha. Irrigation was applied with a rate of 20 mm per week during the warm season.To evaluate the effects on canopy structure we measured specific leaf weight (mg/cm²), average leaf weight (mg), average twig height and average twig length. These variables were selected as they are the most likely to manifest changes over short time periods following changes in environmental conditions.The values of these parameters before initial treatments (autumn 1988) and after treatments (summer 1990) were analyzed. The results obtained show that water and nitrogen have a greater effect than phosphorus on tree canopy structure, at least during initial development.     

Leaf palatability,life expectancy and herbivore damage

Summary Observations on leaves from plants with a wide range of life-forms, ruderals to trees, indicate that palatability to insect herbivores is strongly correlated with the life-expectancy of the leaves. The amount of damage suffered in the field is however inversely correlated with palatability; although the rate of damage is less on unpalatable leaves, their longer life means that they accumulate damage over a longer period. It is only with extremely well-defended evergreen leaves, that the total damage is less than that experienced by less palatable (but short-lived) leaves. These observations are related to the current theories on relative palatability (the apparency theory and the resource availability theory), within the framework of the habitat templet.     

大豆属Soja亚属不同进化型植物叶片演化结构研究

为了探讨大豆属(Glycine)Soja亚属植物的系统演化规律,采用石蜡切片法对产自吉林省的大豆属Soja亚属4种植物的叶片结构进行显微观察。结果显示,Soja亚属中的野生大豆(Glycine sojaSeib.et Zucc.)、半野生大豆(semi-wild soybean)、半栽培大豆(semi-cultured soybean)、栽培大豆(Glycine max(L.)Merrill.)叶片的部分结构特征差异显著;从野生大豆到栽培大豆,其叶片和主脉逐渐加厚、表皮毛数量增多,主脉维管束中导管分子列数增多且逐渐演化出异型维管束,栅栏组织层数逐渐增多,CTR(栅栏组织/叶片厚)和SR(海绵组织/叶片厚)值也有增高的趋势;栽培大豆栅栏组织最发达,已演化出4层栅栏组织细胞。大豆属Soja亚属4种植物(野生大豆、半野生大豆、半栽培大豆、栽培大豆)叶片间的解剖结构差异表现出明显的进化趋势。     

粗叶悬钩子叶中多酚类与三萜类化合物的研究

采用高效液相色谱-串联质谱（HPLC-MS/MS）联用技术,对中国南方民间用于治疗肝损伤和癌症的药材粗叶悬钩子（Rubus aleaefolius Poir.）叶中的多酚类和三萜类成分进行了分析。通过与文献数据和部分对照品的紫外光谱、负离子模式下的一级和二级质谱信息进行比较,从粗叶悬钩子叶中共分析了18个化合物,鉴定了其中2个多酚类化合物,推测了9个多酚类和7个三萜类化合物的可能结构,并对三萜类化合物的质谱裂解途径进行了解析。基于对三萜类化合物裂解规律的研究,推测了1个三萜,即3-对香豆酰氧基-19α-羟基熊果酸。芦丁、绿原酸和3-对香豆酰氧基-19α-羟基熊果酸在本植物中属首次报道。     

射干叶中异黄酮类化学成分的研究

从海南产射干叶中分得8个异黄酮类化合物,通过理化常数测定和光谱分析其化学结构分别鉴定为鸢尾黄酮新苷A(iristectorin A,1)、野鸢尾苷(iridin,2)、鸢尾苷(tectoridin,3)、鸢尾苷元(tectorigenin,4)、次野鸢尾黄素(irisflorentin,5)、染料木素(genistein,6)、染料木苷(genistin,7)、樱黄素(Prunetin,8)。所有化合物均为首次从射干叶中分离得到,其中化合物7和8为首次从鸢尾科植物中分离。     

‘贵长’猕猴桃叶片高效直接再生体系的建立

以‘贵长’猕猴桃叶片为外植体,直接脱分化产生不定芽,并对不定芽增殖以及生根体系进行优化,建立了其高效直接再生体系。结果表明,叶片在MS+4. 0mg/L 6-BA+0. 4mg/L NAA培养基中,不定芽诱导率达95. 8%,平均出芽数达15. 7个/叶片;不定芽在MS+3. 0mg/L 6-BA+0. 3mg/L NAA+0. 2mg/L GA3培养基中,增殖率达100%,且1～6代平均繁殖系数达8. 15;不定芽先在添加1. 0mg/L IBA的1/2 MS固体培养基中诱导7d,然后再先后在1/2 MS固体培养基和充分吸附1/2 MS培养液的珍珠岩中各培养14d,生根率达98. 61%,且根系发育良好; 50株试管苗移栽到以珍珠岩和田间土壤(其体积比为1∶4)为基质的营养钵中,2周后成活49株,成活率达98%。该研究成功建立了‘贵长’猕猴桃叶片高效再生体系,该方法不定芽诱导周期短,出芽率高且数目多,不定芽增殖系数大,生根率高且试管苗根系发达,为‘贵长’猕猴桃离体快速繁殖和遗传转化奠定了基础。