俞藤属—葡萄科一新属

作者在研究中国葡萄科植物过程中发现分布于中国亚热带、尼泊尔和印度卡西山区一些植物种自成一类,与葡萄科现有属的定义不符,命名为一新属-愈藤属（YuaC.L.Li)。文中讨论了它与爬山虎属（Parthenocissus Planch.)、崖爬藤属（TetrastigmaPlanch.)、乌蔹莓属（CayratiaJuss.)和蛇葡萄属（Ampelopsis Michx.)的区别,并在野外和栽培条件下观察了某些重要属级鉴定性状在个体发育过程中的表现,以证明其可靠。为了正确鉴定这个属和种类,给出了包括这些属在内的国产葡萄科植物分属检索表和该属的分种检索表,最后,讨论了俞藤属的地理分布及其意义。     

Effects of below- and aboveground competition from the vines Lonicera japonica and Parthenocissus quinquefolia on the growth of the tree host Liquidambar styraciflua

Detrimental effects of vines on tree growth in successional environments have been frequently reported. Little is known, however, about the relative importance of below and aboveground competition from vines on tree growth. The objective of this study was to quantify and compare the growth responses of Liquidambar styraciflua saplings to below and/or aboveground competition with the exotic evergreen vine, Lonicera japonica (Japanese honeysuckle), and the native deciduous vine, Parthenocissus quinquefolia (Virginia creeper). Soil trenching and/or vine-trellising were used to control the type of vine competition experienced by trees. Comparisons among untrenched treatments tested for effects of belowground competition. Comparisons among trenched treatments tested for effects of aboveground competition. After two growing seasons, Lonicera japonica had a greater effect on the growth of L. styraciflua than did P. quinquefolia. This effect was largely due to root competition, as canopy competition only had a negative effect on tree growth when it occurred in combination with root competition. Leaf expansion was consistently and similarly affected by all treatments which involved belowground competition.     

Visualization of embolism formation in the xylem of liana stems using neutron radiography

Background and Aims

Cold neutron radiography was applied to directly observe embolism in conduits of liana stems with the aim to evaluate the suitability of this method for studying embolism formation and repair. Potential advantages of this method are a principally non-invasive imaging approach with low energy dose compared with synchrotron X-ray radiation, a good spatial and temporal resolution, and the possibility to observe the entire volume of stem portions with a length of several centimetres at one time.

Methods

Complete and cut stems of Adenia lobata, Aristolochia macrophylla and Parthenocissus tricuspidata were radiographed at the neutron imaging facility CONRAD at the Helmholtz-Zentrum Berlin für Materialien und Energie, with each measurement cycle lasting several hours. Low attenuation gas spaces were separated from the high attenuation (water-containing) plant tissue using image processing.

Key results

Severe cuts into the stem were necessary to induce embolism. The formation and temporal course of an embolism event could then be successfully observed in individual conduits. It was found that complete emptying of a vessel with a diameter of 100 µm required a time interval of 4 min. Furthermore, dehydration of the whole stem section could be monitored via decreasing attenuation of the neutrons.

Conclusions

The results suggest that cold neutron radiography represents a useful tool for studying water relations in plant stems that has the potential to complement other non-invasive methods.     

地锦属植物抗寒性生理指标变化分析

通过对五叶与三叶地锦人工低温梯度冷冻处理取样、自然露地越冬和春秋冻融季节取样处理,分别测定实验材料抗寒理化指标的变化规律,研究其抗寒机制与抗寒能力。通过Excel做图处理和SAS数据软件显著性分析,结果表明,可溶性糖与蛋白质含量与电导率的数值随温度的降低呈单峰曲线变化,数据量值差异显著或极显著,在冬季和人工最低温时均达到最高值,POD在秋季和春季保持较高的酶活性,尤其在春季酶活性最高;春季的冻融交替对实验材料的伤害强于秋季;五叶地锦的半致死温度为-26.89℃,三叶地锦的半致死温度为-24.07℃,五叶地锦的抗寒能力、露地越冬能力强于三叶地锦;实验材料在哈尔滨市寒冷的环境中具有一定的越冬能力;实验材料露地越冬后的生长表现与实验结论相一致。     

核基质结合区对转爬山虎芪合酶基因烟草中产生白藜芦醇的作用

采用核基质结合区(MARs)来提高转芪合酶基因(STS)烟草(Nicotianatabacum L.)中白藜芦醇产物的含量.MARs是细胞中能与核基质特异紧密结合的DNA片段,体外结合实验表明克隆自酵母的MARs序列能特异地与烟草核基质结合.芪合酶是白藜芦醇生物合成中的关键酶,用RT-PCR方法从川鄂爬山虎(Parthenocissus henryana(Hemsl.)Diels et Gilg)中克隆了与葡萄芪合酶基因有较高同源性的芪合酶编码区,将其置于CaMV35SΩ强启动子下,分别构建两侧带有MARs及不含MARs序列的表达载体,通过农杆菌介导转化烟草.Northern blot及HPLC等分析表明STS基因已整合至烟草染色体中并正常转录,且表达的外源芪合酶在烟草中可催化其底物合成白藜芦醇产物.与对照相比,MARs的存在使转芪合酶基因烟草中白藜芦醇的含量平均提高了约一倍.MARs在转芪合酶基因植物中的应用也为获得抗病性更强、白藜芦醇含量更高、更保健的转基因果蔬的研究奠定了基础.     

稻田生态系统中3种蜘蛛对白背飞虱的捕食效应研究

应用 二次正交旋转组合设计方法,对稻田生态系统中３种捕食性天敌（三突花蛛Ｍｉｓｕｍｅｎｏｐｓ ｔｒｉｃｕｓｐｉｄａｔａ（Ｔａｂｒｉｃｉｕｓ）、草间钻头蛛Ｈｙｌｙｐｈａｎｔｅｓ ｇｒａｍｉｎｉｃｏｒａ（Ｓｕｎｄｅｖａｌｌ）、真水狼蛛Ｐｉｒａｔａ ｐｉｒａｔｉｃｕｓ（Ｃｌｅｒｋ）和１种害虫（白背飞虱Ｓｏｇａｔｅｌｌａ ｆｕｒｃｉｆｅｒａ（Ｈｏｒｖａｔｈ）的共存系统进行研究,获得了天敌对害虫控制作用的数     

柘叶饲养对家蚕消化液中抗核多角体病毒（BmNPV）相关蛋白活性的影响

为探讨柘叶Cudrania tricuspidata饲养家蚕Bombyx mori易感染核多角体病毒（BmNPV）的机制, 本实验比较研究了分别以柘叶和桑叶Morus alba饲养家蚕后其消化液中抗病毒蛋白活性的差异。结果表明: 家蚕经柘叶饲养后消化液中红色荧光蛋白（red fluorescent protein, RFP）的强度无明显变化, 但柘叶饲养蚕消化液中脂肪酶、 胰蛋白酶的活性显著低于桑叶饲养蚕, 柘叶饲养蚕消化液中脂肪酶和胰蛋白酶的活性分别为1 421.71±202.60 U/L和19.67±8.17 U/mL, 桑叶饲养蚕脂肪酶和胰蛋白酶的活性分别为1 976.03±139.92 U/L和199.18±181.71 U/mL。这些结果说明, 消化液中脂肪酶和胰蛋白酶的活性水平低与柘叶饲养蚕易感染核型多角体病毒（BmNPV）可能相关。     

爬山虎红色素的大孔树脂吸附和分离及理化性质研究

本文比较了六种不同型号的大孔树脂对爬山虎红色素的吸附能力,筛选其中最佳的HPD600树脂作为爬山虎红色素的吸附和分离的树脂;用甲醇作为洗脱剂,洗脱效果好;研究了食品中几种常见的共存物、几种金属离子、氧化剂、温度及光等对爬山虎红色素稳定性的影响。     

Anatomical and chemical studies of vitrified shoots of chestnut regenerated in vitro

The growth of crown-gall cells cultured in vitro ( Nicotiana tabacum L. cv. White Burley and Parthenocissus tricuspidata cv. Veitchii) is inhibited by alstonine (BG-8), a plant alkaloid, the anti-cancer effect of which has previously been demonstrated on animals and plants. The growth of normal cells is only slightly affected. The inhibitory effect of BG-8 on crown-gall cells is antagonized by indole-3-acetic acid (IAA) added to the culture medium. Kinetin associated with IAA does not prevent this inhibitory effect. BG-8 present in the culture medium containing the two types of hormones seems to modify the later hormonal requirement of Parthenocissus crown-gall tissues.
BG-8 exhibits high binding affinity for crown-gall DNA and, therefore, strongly inhibits its in vitro synthesis. The alkaloid has practically no effect on DNA from healthy cells. The inhibition by BG-8 is dependent on the level of DNA strand separation and on the origin and nature of the tissues (crown-gall DNA is more destabilized than healthy DNA; DNA from habituated tissues is intermediate). IAA and kinetin have opposite effects on the in vitro strand separation of the DNAs from crown-gall cells and, consequently, antagonistic effects on DNA replication (IAA stimulates and kinetin inhibits). It is possible to establish a close relationship between in situ development of crown-gall tissues of the two species studied (in the presence or absence of BG-8 or cell-growth factors), in vitro DNA synthesis and DNA strand separation.     

爬山虎植物多糖含量的比较研究

用蒽酮-硫酸比色法对4种栽培和野生的爬山虎果实多糖含量进行了测定,方差分析结果表明野生与栽培同种问多糖含量差异较小,不同种问多糖含量差异较显著。