阴香粉实病简况

本文简单介绍了阴香粉实病的症状、病原、发生规律和防治方法.     

Effects of 60-day NO2 fumigation on growth, oxidative stress and antioxidative response in Cinnamomum camphora seedlings

Objective:To study the oxidative stress and antioxidative response of Cinnamomum camphora seedlings exposed to nitrogen dioxide (NO2) fumigation.Methods:Measurements were made up of the growth,chlorophyll content,chlorophyll fluorescence,antioxidant system and lipid peroxidation of one-year-old C.camphora seedlings exposed to NO2 (0.1,0.5,and 4 μl/L) fumigation in open top chambers over a period of 60 d.Results:After the first 30 d,0.5 and 4.0 μl/L NO2 showed insignificant effects on the growth of C.camphora seedlings.However,exposure to 0.5 and 4.0 μl/L NO2 for 15 d significantly reduced their chlorophyll content (P0.05),enhanced their malondialdehyde (MDA) content and superoxide dismutase (SOD) activity (P0.05),and also significantly reduced the maximal quantum yield of PSII in the dark [the ratio of variable fluorescence to maximal fluorescence (Fv/Fm)] (P0.05).In the latter 30 d,0.5 μl/L NO2 showed a positive effect on the vitality of the seedlings,which was reflected by a recovery in the ratio of Fv/Fm and chlorophyll content,and obviously enhanced growth,SOD activity,ascorbate (AsA) content and glutathione reductase (GR) activity (P0.05);4.0 μl/L NO2 then showed a negative effect,indicated by significant reductions in chlorophyll content and the ratio of Fv/Fm,and inhibited growth (P0.05).Conclusion:The results suggest adaptation of C.camphora seedlings to 60-d exposure to 0.1 and 0.5 μl/L NO2,but not to 60-d exposure to 4.0 μl/L NO2.C.camphora seedlings may protect themselves from injury by strengthening their antioxidant system in response to NO2-induced oxidative stress.     

宜宾油樟对三种农作物种子萌发的化感作用

采用生物测定法研究了宜宾油樟茎、叶水浸提液对玉米、水稻、小麦三种主要农作物种子萌发的化感作用。结果表明,油樟的化感作用和供体植物器官、受体植物种类以及浸提液浓度有密切关系。化感效应总趋势为叶>茎,或玉米>水稻>小麦。在实验设计的浸提液浓度范围内,0.075 g.m l-1的茎、叶浸提液对三种种子萌发的化感作用最强。油樟茎、叶对玉米种子萌发表现为化感促进作用,对水稻、小麦种子萌发表现为化感抑制作用。对种子萌发速率的化感效应敏感指数大大地大于最终发芽率的敏感指数,暗示油樟的化感作用主要是缩短玉米或延迟水稻、小麦种子萌发时间。建议在油樟林附近宜种植玉米,不宜种植水稻、小麦。     

兰科虎舌兰属Epipogium种类增补与修订

报道日本虎舌兰Epipogium japonicum Makino在中国四川西部的新记录，并讨论了该种与虎舌兰E. roseum (D. Don) Lindl.的形态差异。过去将日本虎舌兰处理为虎舌兰的异名是不恰当的。日本虎舌兰间断分布于日本和中国的四川西部高海拔地区及台湾。     

野生花卉的引种驯化(五)

本文介绍了泽兰、垫状迎春、金钟花三种野生花卉的形态特征、自然分布、自然生境、生活习性、园林观赏价值,以及笔者对它们进行引种驯化的情况.     

洞庭湖疫区血吸虫尾蚴及钉螺分布特征研究进展

血吸虫病是严重威胁洞庭湖区居民健康和生活状况的寄生虫病之一,其传播过程中,尾蚴和中间宿主钉螺是控制血吸虫病的重要阶段.本文综述了尾蚴和钉螺分布动态和规律方面的研究,以及疫水测定的主要方法,并进行了初步探讨,为有关部门对洞庭湖疫区日本血吸虫的防治提供综合决策依据.     

正交试验法优化香樟根总黄酮提取工艺

[目的]采用乙醇提取法,优选香樟根总黄酮的提取工艺。[方法]选择乙醇浓度、料液比、提取温度、提取时间为考察因素,采用正交设计L9（34）进行提取工艺优选试验。[结果]回归方程为：Y=13.68X-0.0027,r2=0.998,芦丁浓度在0.0—0.04516mg/mL范围内有良好线性关系,最佳提取工艺为：乙醇的体积分数为50%,料液比为1：20,温度为70℃,提取时间为2h。[结论]优选的提取工艺简单、易行,可作为开发香樟根制剂的依据。     

野生天竺桂叶挥发油化学成分的GC-MS分析

采用水蒸气蒸馏法提取野生天竺桂叶挥发油,利用气相色谱-质谱联用技术分析挥发油化学成分,并以面积归一法测定各成分的相对含量从野生天竺桂叶挥发油中共鉴定了88个化合物,占挥发油总量的83.77％,含量较高的化学成分有β-侧柏烯（12.54％）、1-石竹烯（5.96％）、β-桉叶醇（5.85％）、α-按叶烯（4.53％）等.野生天竺桂叶挥发油成分复杂,以萜类及其衍生物为主,含有多种生物活性成分.     

Impact of elevated CO2 concentration under three soil water levels on growth of Cinnamomum camphora

Forest plays very important roles in global system with about 35% land area producing about 70% of total land net production. It is important to consider both elevated CO2 concentrations and different soil moisture when the possible effects of elevated CO2 concentration on trees are assessed. In this study, we grew Cinnamomum camphora seedlings under two CO2 concentrations （350 μmol/mol and 500μmnol/mol） and three soil moisture levels [80%, 60% and 40% FWC （field water capacity）] to focus on the effects of exposure of trees to elevated CO2 on underground and aboveground plant growth, and its dependence on soil moisture. The results indicated that high CO2 concentration has no significant effects on shoot height but significantly impacts shoot weight and ratio of shoot weight to height under three soil moisture levels. The response of root growth to CO2 enrichment is just reversed, there are obvious effects on root length growth, but no effects on root weight growth and ratio of root weight to length. The CO2 enrichment decreased 20.42%, 32.78%, 20.59% of weight ratio of root to shoot under 40%, 60% and 80% FWC soil water conditions, respectively. And elevated CO2 concentration significantly increased the water content in aboveground and underground parts. Then we concluded that high CO2 concentration favours more tree aboveground biomass growth than underground biomass growth under favorable soil water conditions. And CO2 enrichment enhanced lateral growth of shoot and vertical growth of root. The responses of plants to elevated CO2 depend on soil water availability, and plants may benefit more from CO2 enrichment with sufficient water supply.     

HP LC法测定大黄配伍肉桂后水煎液中大黄酚含量

建立高效液相色谱法测定大黄配伍肉桂后水煎液中大黄酚含量的方法,对不同配伍比例下水煎液中大黄酚含量的变化进行研究。采用热回流法提取样品中的大黄酚,利用HPLC测定提取液中游离态及结合态大黄酚的含量。结果表明,大黄与肉桂配伍后水煎液中大黄酚含量呈现不同程度的下降,并且随配伍比例的变化呈规律性变化,大黄肉桂配伍比例为2∶1时,大黄酚的含量最低。该方法快速、准确、重复性好,可用于大黄配伍肉桂大黄酚含量的测定。