Synergistic repellent and irritant effect of combined essential oils on Aedes aegypti (L.) mosquitoes

This study was designed to compare the behavioral responses of Aedes aegypti to a single essential oil and to a mixture of two or three essential oils using an excito‐repellency test chamber. Mixtures were prepared from essential oils extracted from Litsea cubeba (LC), Litsea salicifolia (LS), and Melaleuca leucadendron (ML). In general, the mixture of essential oils produced a much stronger escape response by Ae. aegypti, regardless of the test conditions. No significant difference in escape responses was seen when the mixture of oils was compared with a standard commercial product containing DEET. Greater contact irritancy was seen from mixed oils of LC and LS than with other mixed oils. Mixtures of LC and LS at 0.075% showed the highest synergistic action (65.5% escaped) compared to that with unmixed oil alone at the same concentration (LC/20% and LS=32.2%). In addition, mixtures of LC and LS at 0.075% demonstrated the highest non‐contact repellency (62.7%) and showed a greater effect than the use of LC (20%) or LS (20.3%) alone. We conclude that mixtures of two essential oils show potential as active ingredients for mosquito repellents.     

长穗偃麦草DREB类基因EeAP2.2 的克隆与序列分析

由于一些基因的特殊碱基序列限制,使得应用一种技术获得基因的全长cDNA序列比较困难。本研究结合RACE和Genome Walking技术从十倍体长穗偃麦草（Elytrigia elongata,2n=70）中克隆了AP2家族的一个全长cDNA序列,命名为EeAP2.2。序列分析表明,该基因具有一个837bp的开放阅读框,编码279个氨基酸残基,含有一个保守的AP2结构域,是AP2大家族的一个新成员。该基因编码的氨基酸序列与GenBank已有的普通小麦AP2家族两个同源基因编码蛋白TaDREB1和TaDREBW50（登录号分别为：AAL01124.1和AAY44605.1）具有98%的氨基酸序列一致性, 与大麦AP2蛋白HvDREB1-a（登录号AAY25517.1）,高羊茅AP2蛋白FaDREB2A （登录号CAG30547.1） 及水稻OsDREB2.2（登录号AY064403）的氨基酸序列一致性分别为 93%、86%、69%。说明该基因与小麦AP2家族基因的同源性最高。本研究除获得了长穗偃麦草一个重要抗逆转录因子基因EeAP2.2的全长cDNA序列外,也提供了一种快速、有效克隆功能基因的方法。     

Butanolides from Methanolic Extract of Litsea glutinosa

Phytochemical investigations of a MeOH extract obtained from the heartwoods of the Litsea glutinosa (Lauraceae) led to the isolation and characterization of four new butenolides, (3R,4S,5S)‐2‐hexadecyl‐3‐hydroxy‐4‐methylbutanolide 1 , litsealactone C ( 2 ), and litsealactone D ( 4 ), litsealactone G ( 5 ), and a new benzoic acid derivative named eusmoside C ( 3 ). The structures of these compounds were elucidated on the basis of spectral studies.     

山鸡椒植物源抑菌成分的筛选研究

以山鸡椒为植物材料,以活性追踪的方法测定了不同组分对几种植物病原菌的抑制活性,并从中分离纯化出一种有效抗菌物质L1。实验结果表明:粗提物不同萃取相中,乙酸乙酯相的抑制作用最好,其对杨树溃疡病菌和苹果霉心病菌抑制率达到75%以上;乙酸乙酯相各个组分对几种植物病原真菌均有一定的抑制活性,其中组分6和组分7抑菌效果强,组分6对苹果霉心病菌抑制率达到100%,组分7对番茄灰霉病菌抑制率达到100%;而对抑菌活性物质L1的抑菌活性研究中,随着L1浓度逐渐升高,对几种病原菌的抑制作用也依次增强,尤其是对苹果霉心病菌的抑制效果更加明显,在供试浓度为0.1 mg/mL时,抑制率达到100%;活性成分L1最终通过波谱学方法和文献对比确定为5,8-二羟基-67,-二甲氧基黄酮。     

Invertébrés Sans Frontières: Large Scales of Connectivity of Selected Freshwater Species among Caribbean Islands

The freshwater fauna (crustaceans, molluscs, fish) of many tropical islands in the Caribbean and Pacific share an amphidromous life‐cycle, meaning their larvae need to develop in saline conditions before returning to freshwater as juveniles. This community dominates the freshwaters of much of the tropics, but is poorly known and at risk from development, in particular dam construction. Amphidromy can theoretically lead to dispersal between different freshwater areas, even to distant oceanic islands, via the sea. The extent and scale of this presumed dispersal, however, is largely unknown in the Caribbean. Recent genetic work in Puerto Rico has shown that many freshwater species have little or no population structure among different river catchments, implying high levels of connectivity within an island, whereas between‐island structure is unknown. We used genetic techniques to infer the geographic scales of population structure of amphidromous invertebrates (a gastropod and a number of crustacean species) between distant parts of the Caribbean, in particular Puerto Rico, Panama and Trinidad. We found virtually no geographic population structure across over 2000 km of open sea for these freshwater species. This implies that they are indeed moving between islands in sea currents as larvae, meaning that continued recruitment requires a continuum of healthy habitat from the freshwater to marine environment. We further discuss the role of amphidromy and suggest its ecological and biogeographic role may be more important than previously presumed.     

海南山苍子芳香油分离纯化工艺

利用分子蒸馏技术提纯海南山苍子油,用GC对山苍子里面柠檬醛质量分数和收率进行分析,实验表明获得高纯度、高收率柠檬醛的工业条件是:转数395 rpm,加料速度1.5滴/s,冷却水-5℃,一次分馏温度45℃、压力1 mbar;二次分流温度60℃,压力1 mbar,柠檬醛的质量分数为95.68%,产率为86.60%。     

A new stem Orthoptera (Archaeorthoptera: Oedischioidea) from the Early Permian of the Saar-Nahe Basin,southwest Germany

The new oedischiine Palatinoedischia elongata nov. gen., nov. sp., is described from the Early Permian of Germany. It is characterized by a very particular broad area between R+M+CuA and CuP of the tegmen. The possible closest relative of this new taxon is the genus Plesioidischia, also from the Early Permian of Germany. They possibly constitute their own clade, but a comprehensive phylogenetic analysis is needed to clarify the whole superfamily Oedischioidea.     

中国豆科和樟科几种植物学名的订正

在编写《Flora of China》过程中,根据标本和文献的查阅,对国产豆科和樟科几种植物学名进行修订。本文记述5个新组合、4个新异名和一个恢复的种名。5个新组合是:垂果山蚂蝗Desmodium strigilosum var.pendenticarpum(C.Z.Gao Q.R.Lai) P.H.Huang,心叶山蚂蝗Desmodium flexuosum var.cordifoliolatum(P.C.Li) P.H.Huang,密毛长柄山蚂蝗Podocarpium densum(C.Chen et X.J.Cui)P.H.Huang,东北长柄山蚂蝗Podocarpium podocarpum var.mandshuricum(Maxim.) P.H.Huang和尖叶长柄山蚂蝗Podocarpium podocarpum var.japon-icum(Matsum.)P.H.Huang.4个新异名如下:李氏木姜子Litsea lii C.E.Chang及其变种能汉木姜子var.nunkao-tahangensis(Liao) Liao作为竹叶木姜子L.pseudoelongata Liou Ho的新异名,竹头角木姜子L.akosensis var.chitouchiaoensis Liao作为台湾木姜子L.hayatae Kanehira的新异名和密毛山蚂蝗Desmodium densum (C.Chen et X.J.Cui)H.Ohashi作为密毛长柄山蚂蝗Podocarpium densum (C.Chen et X.J.Cui)P.H.Huang的新异名。由于Litsea pedicellata一名被占用,恢复Litsea taiwaniana Kamikoti作为黄肉树合法的种名。