薇甘菊柄锈菌在中国南方自然环境下的致病力

将薇甘菊柄锈菌接种于自然环境中,观察薇甘菊发病特征和侵染状况,研究薇甘菊柄锈菌在中国南方自然环境下的适应性和致病力。结果表明:薇甘菊柄锈菌在自然环境下有较好的适应性,接种后的薇甘菊叶片可以出现大量褪绿斑,随后产生黄褐色冬孢子堆,然后逐渐坏死和脱落;并且可以成功侵染野生薇甘菊,完成侵染循环。     

安婀珍蝶的生物学及其寄主专一性

对外来入侵植物薇甘菊天敌昆虫安婀珍蝶的生物学及其寄主专一性进行了研究。在温度2 6℃、RH80 %的人工气候箱内饲养 ,安婀珍蝶一个世代历期 92～ 1 0 2d,卵产于薇甘菊叶片上 ,幼虫在四龄前群聚生活 ,六龄后在支持物上化蛹 ,蛹期约 1 1d ,成虫存活约 8d。选择 42科 86种植物进行寄主专一性测定 ,结果表明 :安婀珍蝶对薇甘菊的嗜食程度明显高于其他供试植物 ,且仅能在薇甘菊、飞机草上完成世代     

薇甘菊的天敌调查初报

经调查和鉴定，我国假泽兰属有两种：原产种为假泽兰Mikania cordata,分布海南省和广东省，不造成为害；入侵种为薇甘菊Mikania micrantha，分布广东、香港和台湾等地，造成严重为害。在假泽兰上采到假泽兰瘤瘿螨Aceria mikaniae(Nalepa)，是我国新记录，对假泽兰的生长有较大的抑制作用。薇甘菊有明显的驱避作用，绣线菊蚜Aphis citricolor可致薇甘菊叶片萎缩；在深圳、珠海等地发现薇甘菊上病害普遍，是假尾孢菌属一种真菌Pseudocercospora sp．所致。在有些地方发现菟丝子Cuscuta Japonica Choisy寄生薇甘菊，能否用来抑制薇甘菊的生长，值得探讨。     

薇甘菊中多元素分析及富集研究

本文采用ICP-MS法对薇甘菊不同部位的Pb、Cd、Cr、As、Fe、Mn、Cu和Zn等8种微量元素进行检测,结果显示Fe、Mn、Cu、Zn含量较高,Pb、Cd、Cr和As含量相对较低;不同地区薇甘菊中Pb含量相差较大;不同部位元素含量根中Pb最高,Cu、Zn含量从根、茎、叶依次升高。根据检测结果,从微量元素分布及其富集形态层面对薇甘菊的元素成分进行了剖析,探讨了薇甘菊的综合防治和生物利用前景。     

菟丝子致死薇甘菊

薇甘菊Mikania micrantha是入侵的害草，已经由珠江三角洲扩散到粤东、粤西沿海地区，以及部分山区。在薇甘菊的天敌调查中看到菟丝子寄生于薇甘菊，严重时可以把薇甘菊致死。我们在本所的实验园中栽种薇甘菊，并让其被菟丝子Cusuta chinensis Lam.寄生，结果证实菟丝子在两个月左右，完全可以抑制薇甘菊的生长，最终把薇甘菊致死。这可能是以草治草的一种新途径，但是菟丝子也是我国农作物的一种重要昌，如何利用菟丝子控制薇甘菊的为害，而又不使菟丝子对薇甘菊的伴生植物和鞭它农作物造成为害，是下一步要解决的问题，菟丝子致死薇甘菊的机理更需要深入研究。     

薇甘菊对桔小实蝇的驱避试验初报

为了探索一种低毒、低残留的环保型驱避剂，分别在广州市番禺区杨桃园和广东省昆虫研究所大院内，以薇甘菊Mikania micrantha H．B．K对桔小实蝇Bactrocera dorsalis（Hendel）成虫进行驱避试验。结果表明，薇甘菊对桔小实蝇具有明显的驱避效果，在薇甘菊环境内诱杀桔小实蝇虫数明显低于正常环境诱杀虫数，全年1，12月薇甘菊环境内对桔小实蝇的驱避率为13．33-92．78％，全年平均驱避率为50．65％；杨桃园内，以薇甘菊甲醇提取物喷施的杨桃，可以把本地种杨桃的桔小实蝇为害率控制在50％以下，而对照的为害率超过80％。     

外来植物薇甘菊的开发利用前景

薇甘菊是一种危害极大的外来入侵植物,近年来薇甘菊防控技术与途径的研究成为薇甘菊研究的热点,但薇甘菊作为一种生物资源也一直受到关注.从薇甘菊在害虫防治、病原微生物防治、生态环境影响以及其他应用等方面进行了详细介绍,并对薇甘菊的开发利用前景进行探讨与展望,以开拓薇甘菊防治的新思路.     

薇甘菊吸附亚甲基蓝的研究

研究薇甘菊活体在不同pH值、初始浓度、吸附时间条件下对水体中亚甲基蓝的吸附能力,并对薇甘菊的再生及重复吸附能力进行测试。结果表明:常温下,在亚甲基蓝溶液浓度为5~20 mg/L、pH值为8的亚甲基蓝溶液中,薇甘菊活体培养3 d后对亚甲基蓝的去除率可达99%。同一株薇甘菊可以在浓度为10 mg/L、pH值为8的亚甲基蓝溶液中循环培养4次吸附效果最佳,去除率均可达到90%以上,吸附效果良好。     

薇甘菊化感作用的初步研究

对薇甘菊(Mikaniamicrantha)提取物乙醇部分的化感作用进行了初步研究。结果表明,薇甘菊提取物乙醇部分对水稻、萝卜、黄瓜、菜心具有不同程度的化感作用,总体上呈现出低促高抑的现象,且随着溶液浓度增大而抑制作用增强。其中干物质为0.1g/ml的乙醇部分溶液对菜心的种子萌发,幼苗生长,根长生长抑制作用最为明显;干物质为0.01g/ml溶液对水稻的根长生长有明显的促进作用;干物质为0.002g/ml溶液对水稻,菜心的种子萌发,幼苗生长,根长生长也有一定的促进作用。     

薇甘菊化感作用的初步研究

薇甘菊(M ikania m icrantha)提取物乙醇部分对水稻、萝卜、黄瓜、菜心具有不同程度的化感作用,总体上呈现出低促高抑的现象,且随着溶液浓度增大而抑制作用增强。其中干物质为0.1 g/m l的乙醇部分溶液对菜心的种子萌发、幼苗生长、根长生长抑制作用最为明显;干物质为0.01 g/m l溶液对水稻的根长生长有明显的促进作用;干物质为0.002 g/m l溶液对水稻、菜心的种子萌发、幼苗生长、根长生长也有一定的促进作用。     

30种除草剂对豚草和薇甘菊的防效初步评价

为了筛选出防除豚草和薇甘菊的新型高效除草剂品种,采用茎叶喷雾法,测定30种除草剂对盆栽豚草和薇甘菊的防除效果。辛酰溴苯腈375 g /hm2、麦草畏216 g /hm2、百草枯600 g /hm2、草铵膦540 g /hm2、草甘膦异丙胺盐922.5 g /hm2、乙羧氟草醚90 g /hm2、三氟羧草醚540 g /hm2、氟磺胺草醚427 g /hm2、莠去津1 140 g /hm2、莠灭净3 000 g /hm2和灭草松1 440 g /hm2对豚草防除效果好,药后30 d鲜重防效达100%;对薇甘菊防效较好的有辛酰溴苯腈375 g /hm2、麦草畏216 g /hm2、2,4-滴钠盐125 g /hm2、氯氟吡氧乙酸180 g /hm2、氯氟吡氧乙酸异辛酯150 g/hm2、草铵膦540 g /hm 2、草甘膦异丙胺盐922.5 g /hm2、灭草松1 440 g /hm2和百草枯600 g/hm2,药后30天鲜重防效达98%以上。本试验结果将为豚草和薇甘菊的化学防控提供有益参考。     

Potential allelopathic effects of Mikania micrantha on the seed germination and seedling growth of Coix lacryma‐jobi

The allelopathic potential of Mikania micrantha H.B.K. to affect the seed germination and seedling growth of Coix lacryma‐jobi L. was investigated. Water‐soluble allelopathic substances were found in the water extracts of M. micrantha. The effect of the water extracts on the seed germination and seedling growth of C. lacryma‐jobi was concentration‐dependent. The water extracts from the different plant parts (leaf, stem, and root) of M. micrantha differed in their effect on the germination and seedling growth of C. lacryma‐jobi, with the effect of the leaf extract being the least inhibitory. The malondialdehyde (MDA) content in the C. lacryma‐jobi seedlings increased by 64%, 45%, and 52% of the control with increasing concentrations of the extracts of the root, stem, and leaf (80, 400, and 400 g L^?1, respectively). The extract from the M. micrantha roots significantly increased the catalase (CAT) activity of the C. lacryma‐jobi seedlings (48% and 54% of the control at the concentrations of 20 g L^?1 and 80 g L^?1, respectively). The extracts from the leaves and stems at low concentrations increased the CAT activity, but at high concentrations, the extracts decreased the CAT activity. The extracts from the roots, stems, and leaves at concentrations of 80, 400, and 400 g L^?1 also significantly decreased the peroxidase (POD) activity of the C. lacryma‐jobi seedlings to 27%, 52%, and 34% of the control, respectively. These results indicate that the water extracts of M. micrantha could inhibit the seed germination and seedling growth of C. lacryma‐jobi through the regulation of anti‐oxidase activity, such as POD and CAT in the cells. The growth inhibition of the C. lacryma‐jobi seedlings is probably related to injury after oxidization of the cell membranes with the increase of MDA content.     

Ecophysiological attributes of Mikania micrantha,an exotic invasive weed,at two different elevations in the tropical forest regions of the Western Ghats,South India

Mikania micrantha H.B.K. is a fast‐growing, perennial vine and one of the world's worst alien invasive weeds. It is a major threat to agro‐ecosystems, plantation crops and agro‐forestry systems. An attempt was made to understand the physiological adaptation and ecological amplitude of M. micrantha at two different altitudes and seasons in the Western Ghats of south India. The relationships between the net photosynthetic rate (P_N) and other physiological parameters, like stomatal conductance (g_s), transpiration rate, intercellular CO₂ concentration, vapor pressure deficit and water use efficiency, and environmental factors, like photosynthetically active radiation (PAR), leaf temperature and air temperature, were analyzed in order to understand their physiological adaptabilities. The P_N exhibited a peak at 10.00 hours and declined gradually at both elevations; however, the populations at the lower elevation had a significantly greater P_N than the populations at the higher elevation in November. The P_N and g_s were positively correlated with the PAR. Under significantly different PAR levels, the difference in the average P_N was not significant for summer but was significant for winter between the two elevations. It suggested that the photosynthetic ability of M. micrantha is not affected by a difference in altitude (451 m and 912 m), as the differences in the environmental parameters were inconspicuous between the two elevations. These results indicated that this weed possesses great phenotypic plasticity and thrives better at lower elevations.     

蓼蓝齿胫叶甲寄主专食性的研究

对11科36种植物测试的结果表明，蓼蓝齿胫叶甲嗜食蓼科植物，尤其喜食酸模属和蓼属的植物，专食性强。蓼蓝齿胫叶甲在酸模、巴天酸模和皱叶酸模上产卵量多，发育进度快，幼虫死亡率低，羽化率高；经田间多点、多次调查，由于蓼蓝齿胫叶甲的取食，使酸模、巴天酸模和皱叶酸模自然死亡率达90％以上。强迫取食试验未发现危害任何经济作物。该虫蓼科杂草上繁殖力强，对自然控制蓼科杂草起重要作用，有一定的应用价值。