外来西方蜜蜂放蜂密度对云南罗平本地传粉蜂群落结构及物种多样性的影响

【目的】近年来随着交通条件的改善,每年有大量西方蜜蜂Apis mellifera蜂场从全国各地赶到云南放蜂。本研究旨在揭示西方蜜蜂这一外来蜂种对云南本地传粉蜂种类、数量及其物种多样性的影响。【方法】采用马来氏网收集、调查了云南省罗平县西方蜜蜂高放蜂密度试验点(鲁特和走马田)、中放蜂密度试验点(外纳和下阿列)和低放蜂密度试验点(马把和下庄科)共6个试验点包括山林生境和农田生境的本地传粉蜂群落结构;并对比分析了不同放蜂密度、不同生境下各试验点传粉蜂物种多样性指数(H′)、均匀度指数(J′)及丰富度指数(Dm)之间的差异。【结果】采集到的1 715头本地传粉蜂隶属于10科53种,其中蜜蜂科(Apidae)、隧蜂科(Halictidae)和胡蜂科(Vespidae)为优势类群,东方蜜蜂Apis cerana和切淡脉隧蜂Lasioglossum excisum为优势种。在放蜂密度(试验点周围3 km范围内西方蜜蜂蜂群数量)为723～2 750群这一变动范围内,各试验点本地传粉蜂物种数量、个体数量均随西方蜜蜂放蜂密度的增大而减少,物种多样性指数(H′)及丰富度指数(Dm)也相应降低,但西方蜜蜂放蜂密度对本地传粉蜂均匀度指数(J′)没有影响。此外,在相同放蜂密度下,山林生境的本地传粉蜂物种多样性均显著高于农田生境。【结论】云南罗平本地传粉蜂的群落结构及物种多样性受西方蜜蜂放蜂密度的影响,在放蜂密度从723～2 750群这一变动范围内,放蜂密度越大,本地传粉蜂的个体数、物种数、多样性指数和丰富度指数越小。本研究结果为进一步研究合理控制西方蜜蜂放蜂密度以保护云南本地传粉蜂种的多样性提供了思路。     

Induction of diapause and seasonal morphs in butterflies and other insects: knowns,unknowns and the challenge of integration

The ‘choice’ of whether to enter diapause or to develop directly has profound effects on the life histories of insects, and may thus have cascading consequences such as seasonal morphs and other less obvious forms of seasonal plasticity. Present knowledge of the control of diapause and seasonal morphs at the physiological and molecular levels is briefly reviewed. Examples, mainly derived from personal research (primarily on butterflies), are given as a starting point with the aim of outlining areas of research that are still poorly understood. These include: the role of the direction of change in photoperiod; the role of factors such as temperature and diet in modifying the photoperiodic responses; and the role of sex, parental effects and sex linkage on photoperiodic control. More generally, there is still a limited understanding of how external cues and physiological pathways regulating various traits are interconnected via gene action to form a co‐adapted complete phenotype that is adaptive in the wild despite environmental fluctuation and change.     

Blockage of glucocorticoid receptors during memory acquisition, retrieval and reconsolidation prevents the expression of morphine-induced conditioned place preferences in mice

Association between the reward caused by consuming drugs and the context in which they are consumed is essential in the formation of morphine-induced conditioned place preference (CPP). Glucocorticoid receptor (GRs) activation in different regions of the brain affects reward-based reinforcement and memory processing. A wide array of studies have demonstrated that blockage of GRs in some brain areas can have an effect on reward-related memory; however, to date there have been no systematic studies about the involvement of glucocorticoids (GCs) in morphine-related reward memory. Here, we used the GR antagonist RU38486 to investigate how GRs blockage affects the sensitization and CPP behavior during different phases of reward memory included acquisition, retrieval and reconsolidation. Interestingly, our results showed RU38486 has the ability to impair the acquisition, retrieval and reconsolidation of reward-based memory in CPP and sensitization behavior. But RU38486 by itself cannot induce CPP or conditioned place aversion (CPA) behavior. Our data provide a much more complete picture of the potential effects that glucocorticoids have on the reward memory of different phases and inhibit the sensitization behavior.     

溶藻弧菌溶血活性检测及溶血素基因、启动子区功能

[目的]研究溶藻弧菌的溶血现象,溶血素基因vah的分布及vah基因、vah启动子区对溶藻弧菌溶血活性的贡献.[方法]对46株分离自华南沿海水生动物体内和海水的溶藻弧菌环境株及溶藻弧菌标准株1.1587进行溶血实验;比较具有溶血活性的溶藻弧菌野生株ZJ051、vah基因大肠杆菌BL21重组表达株、vah缺失突变株和基因回补株间溶血能力的差异;检测vah基因在溶藻弧菌中的分布,比较溶血株与非溶血株vah基因及上游启动子区的序列差异.[结果]47.8％的溶藻弧菌菌株产生溶血活性,因此溶血现象普遍存在于溶藻弧菌环境株中;vah基因的表达产物具有溶血活性,vah基因缺失突变株不具有溶血活性,而vah基因回补株恢复溶血活性.vah基因普遍存在于溶藻弧菌中,且基因序列非常相似,氨基酸序列完全相同,然而不同菌株的启动子区第188-190碱基位点存在差异.[结论]溶藻弧菌vah基因是造成溶藻弧菌溶血的直接原因,但溶藻弧菌溶血能力的差异并非是由vah基因本身差异决定,极有可能与启动子区第188-190碱基位点相关.     

New fossil hangingflies (Insecta: Mecoptera: Raptipedia: Cimbrophlebiidae) from the Middle Jurassic of Inner Mongolia,China

Abstract: Two new genera with six new species of hangingflies (Mecoptera: Raptipedia: Cimbrophlebiidae) are described. They were collected from the Middle Jurassic nonmarine sedimentary strata of the Jiulongshan Formation in Daohugou, Inner Mongolia, north‐eastern China. This report of Cimbrophlebiidae from the Yanliao Biota provides detailed morphological information and evidence of a broad diversity of Cimbrophlebiidae during the Middle Jurassic. A key to the known species of Cimbrophlebiidae is provided.     

Different utilizable substrates have different effects on cometabolic fate of imidacloprid in Stenotrophomonas maltophilia

Imidacloprid, the largest selling insecticide in the world, is more stable in soil, and its environmental residue and effects are attracting people's close attention. One of imidacloprid metabolism pathways was degraded to CO₂ through olefin imidacloprid pathway. Here, we report that sucrose as a utilizable substrate enhanced the cometabolism of imidacloprid by Stenotrophomonas maltophilia CGMCC 1.1788 to produce 5-hydroxy imidacloprid, whereas when succinate was used as a utilizable substrate, 5-hydroxy imidacloprid from imidacloprid was transformed to olefin imidacloprid, and the latter was further degraded. The hydroxylation of imidacloprid required NAD(P)H, whereas the dehydration of 5-hydroxy imidacloprid to form olefin imidacloprid required succinate rather than NAD(P)H. NADPH greatly favored the hydroxylation of imidacloprid more than NADH, and NADPH inhibited the dehydration of 5-hydroxy imidacloprid to olefin imidacloprid, but NADH did not. Therefore, sucrose may be metabolized through hexose monophosphate pathway to produce mainly NADPH which participated in the hydroxylation of imidacloprid to 5-hydroxy imidacloprid and meanwhile inhibited the dehydration of 5-hydroxy imidacloprid to olefin imidacloprid, whereas succinate may be metabolized mainly through the tricarboxylic acid cycle to produce NADH which was involved in hydroxylation of imidacloprid to 5-hydroxy imidacloprid but did not inhibit the dehydration of 5-hydroxy imidacloprid to olefin imidacloprid. Our results have a significant meaning in further understanding the influence of different utilizable substrates on the cometabolic pathways and the fate of environmental imidacloprid.     

崇明东滩鸟类栖息地优化区越冬水鸟的栖息地利用及影响因子

阐明水鸟栖息地利用与环境因子的关系有助于制定针对性的水鸟保护对策。本研究在2012~2013年冬季对崇明东滩鸟类栖息地优化区内越冬水鸟的种类、数量以及6种环境因子(植被面积比例、裸地面积比例、水深、地形变异、栖息地结构多样性和干扰)进行调查,以了解水鸟对人工湿地的栖息地利用及其影响因子。野外调查共记录到水鸟24种9 018只,其中优势种为斑嘴鸭(Anas poecilorhyncha)和绿头鸭(A.platyrhynchos);栖息地优化区内水鸟休息的个体数量占总数量的79.2%,这表明优化区是大多数水鸟的休息地,而小(Tachybaptus ruficollis)、白骨顶(Fulica atra)、黑水鸡(Gallinula chloropus)、白琵鹭(Platalea leucorodia)和黑脸琵鹭(P.minor)的觅食个体数量超过60%,说明优化区也为这些鸟类提供了觅食地。逐步回归分析表明,裸地面积比例是影响越冬水鸟种类分布的最主要因子;尽管游禽在地形变异较大、植被面积比例较低的区域数量较多,但在休息时游禽更偏好于裸地面积比例较高的区域,而涉禽休息时偏好于地形变异较大的区域。为增加栖息地优化区内的水鸟多样性,建议在优化区内种植水鸟可食的沉水植物以增加水鸟的食物资源,同时增加裸地面积比例和地形变异程度,更好地为水鸟提供栖息地。