Dual Effect of Phenolic Nectar on Three Floral Visitors of Elsholtzia rugulosa (Lamiaceae) in SW China

Some plants secrete toxic nectar to appeal to most effective pollinators and deter non-pollinators or nectar thieves; however available information about ecological function of toxic nectar remains scarce. Elsholtzia rugulosa stands out as a plant with toxic nectar recorded in SW China. We focused on the functional significance of the phenolic compound that imparts toxic to the nectar of E. rugulosa. The effects of phenolic nectar were studied in three visitors of the flowers of the winter-blooming E. rugulosa Hemsl. (Lamiaceae) in SW China. The pollinating species Apis cerana Fabricius (Apidae; Asian honey bee) and two occasional visitors, Vespa velutina Lepeletier (Vespidae; yellow-legged Asian hornet) and Bombus eximius Smith (Apidae; a bumble bee) were tested for their preferences for low and high concentrations of 4-hydroxybenzoic acid in hexose and sucrose solutions. The pollinator is important for the plant, which is dependent on pollinator visits to attain a higher seed production and it is most likely that the combination of phenolic toxic nectar and the adaptation to phenolic nectar by A. cerana delivers an evolutionary advantage to both actors. The low and high concentrations of the phenolic acid were nearly totally refused by both occasional visitors V. velutina and B. eximius and were preferred by the pollinator A. cerana. E. rugulosa gains by having a much higher seed production and the pollinating honey bee by having an exclusive and reliable food source during the winter season at high altitudes in SW China. We found that the function of the toxic phenolic compound has dual roles by appealing to legitimate pollinators and deterring non-pollinators of E. rugulosa.     

25S rDNA在杨属植物染色体上的定位

利用荧光原位杂交技术对杨属(Populus)植物五个组中二倍体(2n=2x=38)代表种:毛白杨(P.tomentosa)、箭杆杨(P.nigravar.thevestina)、大叶杨(P.lasiocarpa)、小青杨(P.pseudo-simonii)、胡杨(P.euphratica);以及所发现的白杨组和黑杨组天然三倍体(2n=3x=57):毛白杨(P.tomentosa)、武黑1号(P.euramericana cv.Wuhei-1)进行了25S rDNA的染色体定位。二倍体毛白杨、箭杆杨、小青杨和大叶杨都具有4个25S rDNA位点,而胡杨只有2个较大的25S rDNA定位于1对小的染色体上,白杨和黑杨天然三倍体的两个种各有6个25S rDNA位点。同时作者还将杨属植物25S rDNA的分布变化与常规核型分析结果进行了比较。     

New cytotoxic metabolites from a deep-sea-derived fungus, Phialocephala sp., strain FL30r

Two new sorbicillinoids, 1 and 2 , together with a novel benzofuranone derivative named phialofurone ( 3 ), were isolated from a deep‐sea sediment‐derived fungus, Phialocephala sp. Their structures were established on the basis of spectroscopic data. All compounds displayed cytotoxic effects against P388 (IC₅₀ values of 11.5±1.4, 0.1±0.1, and 0.2±0.01 μM , resp.) and K562 (IC₅₀ values of 22.9±0.8, 4.8±0.3 and 22.4±0.9 μM , resp.) cell lines.     

利用噬菌体展示技术筛选胰岛素模拟肽

为了寻找能够模拟胰岛素生物活性的小肽,以胰岛素多克隆抗体为靶标,筛选噬菌体展示随机C7C环肽库.3轮筛选后,通过ELISA方法挑取与靶分子特异性结合的15个阳性克隆,测序获得两条序列,分析所得序列并合成相应短肽.通过细胞生物学活性检测,小肽CPTSQANSC（ZJ1）能够竞争性的抑制胰岛素与其受体的结合,并对正常小鼠和四氧嘧啶诱导的糖尿病小鼠,都有明显的降血糖作用.上述结果表明,小肽CPTSQANSC具有胰岛素样生物学活性.而小肽CVQPSHSSC（ZJ2）表现出胰岛素拮抗活性,能引起正常小鼠血糖升高.这表明筛选到了能够模拟胰岛素表位的短肽CPTSQANSC,可能为治疗胰岛素依赖性糖尿病提供了新线索.     

The laboratory evaluation of repellent effect of camouflage face paint mixed with DEET to Aedes albopictus

参照中华人民共和国国家标准GB/T 17322.10-1998和《军队特需药品研发勤务技术指导原则(试行)》规定的测试方法,测试了避蚊胺和水溶性二氧化钛处理迷彩油(CFP)对白纹伊蚊Aedes albopictus的驱避效果,为研发我军专用的防蚊虫迷彩油提供依据.结果表明:在3种颜色迷彩油中加入DEET后,不影响DEET的驱蚊效果;添加不同浓度DEET对蚊虫的驱避效果差异显著,20％dEET和25％dEET+迷彩油对白纹伊蚊的平均防护时间均达到或超过10h,达到《军队特需药品研发勤务技术指导原则(试行)》规定的标准,15％dEET+迷彩油平均防护时间不足10h,未达《军队特需药品研发勤务技术指导原则(试行)》规定的标准.研究表明:将适量DEET与迷彩油混合涂抹于皮肤可能作为演习或战时的伪装和防蚊的一种有效的综合保护措施.     

三色迷彩油添加避蚊胺对白纹伊蚊驱避效果的实验室评价

参照中华人民共和国国家标准GB/T 17322.10-1998和《军队特需药品研发勤务技术指导原则(试行)》规定的测试方法,测试了避蚊胺和水溶性二氧化钛处理迷彩油(CFP)对白纹伊蚊Aedes albopictus的驱避效果,为研发我军专用的防蚊虫迷彩油提供依据。结果表明:在3种颜色迷彩油中加入DEET后,不影响DEET的驱蚊效果;添加不同浓度DEET对蚊虫的驱避效果差异显著,20%DEET和25%DEET+迷彩油对白纹伊蚊的平均防护时间均达到或超过10 h,达到《军队特需药品研发勤务技术指导原则(试行)》规定的标准,15%DEET+迷彩油平均防护时间不足10 h,未达《军队特需药品研发勤务技术指导原则(试行)》规定的标准。研究表明:将适量DEET与迷彩油混合涂抹于皮肤可能作为演习或战时的伪装和防蚊的一种有效的综合保护措施。     

Colored nectar as an honest signal in plant-animal interactions

Many flowering plants obtain the services of pollinators by using their floral traits as signals to advertise the rewards they offer to visitors—such as nectar, pollen and other food resources. Some plants use colorful pigments to draw pollinators’ attention to their nectar, instead of relying on the appeal of nectar taste. Although this rare floral trait of colored nectar was first recorded by the Greek poet Homer in the Odyssey, it has only recently received the attention of modern science. This mini-review focuses on recent findings about some of the species that use colored nectar; topics include its function as an honest signal for pollinators, as well as the pigments responsible for the nectar coloration. Such research of the ecology and physiology of colored nectar expands our understanding of the role and evolution of pollinator signaling in plants.     

钝叶榕果实内繁殖的两种榕小蜂与寄主榕树间的协同进化

 榕树(Ficus)及其传粉榕小蜂(Agaonidae)构成了高度专一的互惠共生体系。榕树的果实(以下简称榕果)内也寄生着一些非传粉小蜂。 绝大多数非传粉小蜂在榕果外把产卵器刺入果壁产卵到果腔内, 只有极少数种类能够进入果腔内产卵。在西双版纳地区, 钝叶榕(Ficus curtipes)上的杨氏榕树金小蜂(Diaziella yangi)类似于传粉者钝叶榕小蜂(Eupristina sp.), 它也是进入榕果内产卵繁殖后代的, 这就为比 较研究榕果内产卵小蜂与寄主榕树间的关系提供了材料。该文从形态学、行为学和生态学角度比较研究了这两种进入榕果内产卵的小蜂与寄主 钝叶榕之间的作用关系, 研究结果显示: 1)杨氏榕树金小蜂与钝叶榕小蜂的雌蜂头部形状存在趋同进化; 2)两种小蜂的产卵器的平均长度都比 雌花花柱长, 因而能把卵产在子房里; 3)钝叶榕小蜂从瘿花出来需要3~5 h, 交配需要17~19 min, 杨氏榕树金小蜂从瘿花出来只需18~20 min, 交配时间为20~30 s; 4)在自然群落中, 大约90%的雌花期榕果里都只进一只杨氏榕树金小蜂和一只钝叶榕小蜂, 杨氏榕树金小蜂能通过传粉来 增加榕树种子数量, 但对钝叶榕小蜂种群的繁衍造成了极显著的负面影响; 5)两种小蜂于同一时期进入榕果内繁殖, 子代同期成熟羽化, 发育 期与榕树雄花的发育期同步。研究表明: 进入榕果内繁殖的两种小蜂与寄主榕树之间存在着协同进化关系, 杨氏榕树金小蜂为榕树有效地传粉, 这可能是一个由寄生者向互惠方向进化的实例。     

Dynamics variation of seeds and fig wasps on <Emphasis Type="Italic">Ficus glaberrima</Emphasis> in Xishuangbanna,SW China

Fig wasps associated with Ficus glaberrima were investigated in Xishuangbanna, China. A total of 97 figs from the same sample tree were collected over a period of three years, and 5171 fig wasps were recorded. Our results showed that Eupristina sp. progeny was not correlated with seeds in the three years. D. bizarrea only negatively affected Eupristina sp. and there was no obvious negative effect of D. bizarrea on seeds. The colonization rate of Eupristina sp. in December 2006 (dry season) was highest, while the colonization rate of D. bizarrea in August 2007 (rainy season) was highest. The colonization rates of Eupristina sp. and D. bizarrea were almost equal in December 2006 and July 2008 (rainy season). The number of Eupristina sp. progeny per fig during the colder month (December 2006) was significantly higher than during the warmer month (August 2007; July 2008) (LSD: P<0.05). There was no significant difference in the number of D. bizarrea progeny during three years. Eupristina sp., D. bizarrea, Sycoscapter sp., and Philotrypesis sp. occurred consistently as the most common fig wasps every year. This result suggested that some fig wasps showed a certain degree of season recurrence or specificity, but that the composition of fig wasps was not conspicuously influenced by the seasonal factor.