Pheromone source location by flying moths: a supplementary non-anemotactic mechanism

After the wind was stopped in an insect flight tunnel, male oriental fruit moths continued to fly in zigzag fashion along a stationary pheromone plume. Their lateral excursions from the time-averaged pheromone plume were no greater without wind than in wind of 38 centimeters per second. When the pheromone plume was removed and the wind stopped, males initiated wider track reversals when they reached the pheromone-free area in still air than they had made while in the pheromone plume. This non-anemotactic mechanism of maintaining plume contact-possibly a special kind of klinotaxis-when coupled with the orthokinetic retinal velocity of apparent ground pattern motion, allowed males to reach the pheromone source area from 1 to 2 meters away without wind.     

Chemical trail-following by flying insects: a mechanism for orientation to a distant odor source

An aerial trail of odorous pheromone molecules extends downwind from a female pink bollworm moth that is receptive for mating. Males apparently sense the boundaries of the trail during their characteristic zigzag flights across it. Contrary to previous beliefs, the mechanism by which the males steer toward the odor source does not require a sensing of wind direction.     

叩甲科昆虫性信息素研究及应用

应用昆虫性信息素进行害虫监测和防治是害虫综合治理重要措施之一.金针虫是一类重要的地下害虫,食性杂,危害隐蔽,成虫期是其唯一暴露的时期,利用叩甲性信息素是金针虫种群动态监测和防治的重要手段.该文对叩甲科昆虫性信息素的提取、分离鉴定及应用现状进行了综述,以期对中国在叩甲性信息素的研究提供一定参考.     

Chemically derived, ultrasmooth graphene nanoribbon semiconductors

We developed a chemical route to produce graphene nanoribbons (GNR) with width below 10 nanometers, as well as single ribbons with varying widths along their lengths or containing lattice-defined graphene junctions for potential molecular electronics. The GNRs were solution-phase-derived, stably suspended in solvents with noncovalent polymer functionalization, and exhibited ultrasmooth edges with possibly well-defined zigzag or armchair-edge structures. Electrical transport experiments showed that, unlike single-walled carbon nanotubes, all of the sub-10-nanometer GNRs produced were semiconductors and afforded graphene field effect transistors with on-off ratios of about 10(7) at room temperature.     

Insect sex-pheromone signals mediated by specific combinations of olfactory receptors

We describe two male-specific olfactory receptors (ORs) in the silk moth, Bombyx mori, that are mutually exclusively expressed in a pair of adjacent pheromone-sensitive neurons of male antennae: One is specifically tuned to bombykol, the sex pheromone, and the other to bombykal, its oxidized form. Both pheromone ORs are coexpressed with an OR from the highly conserved insect OR subfamily. This coexpression promotes the functional expression of pheromone receptors and confers ligand-stimulated nonselective cation channel activity. The same effects were also observed for general ORs. Both odorant and pheromone signaling pathways are mediated by means of a common mechanism in insects.     

迷向处理对梨小食心虫的防治效果

为明确迷向处理对梨小食心虫的防治效果,为生产中的合理使用提供理论依据,选用澳大利亚BioGlobal公司产梨小食心虫迷向丝和中国科学院动物所产梨小食心虫迷向诱芯在陕西省梅县桃园进行了迷向防治试验。结果表明,迷向丝和迷向诱芯对梨小食心虫均有明显的迷向和防治效果。迷向处理96 d后,各处理的迷向率都在90%以上,防效均在64%以上,且迷向丝和迷向诱芯不同处理间迷向和防效均无显著差异。据此建议生产上使用255条.hm-2迷向丝或450只.hm-2迷向诱芯更为经济。     

昆虫性信息素在害虫防治中的应用

目前,应用性信息素防治害虫已成为害虫防治领域的一项重要技术。对性信息素诱捕技术在害虫防治中的应用进行了综述,重点介绍了昆虫性信息素诱捕效果的影响因素、植物挥发物与昆虫性信息素的协同增效作用、利用性信息素进行虫情的预测预报等。     

诱捕器对烤烟斜纹夜蛾的防治效果研究

[目的]探讨诱捕器对烤烟斜纹夜蛾的防治效果。[方法]调查并分析了斜纹夜蛾性诱剂、化学药剂和空白对照处理对烤烟斜纹夜蛾的防控效果。[结果]斜纹夜蛾性诱剂诱捕蛾量呈明显的高峰期和峰次。性诱剂防控区比空白对照区的虫口密度平均减退70.5%;比常规药剂控制区的虫口密度平均减退7.1%,降低成本35.6%。[结论]斜纹夜蛾性诱剂对烤烟斜纹夜蛾有较强的诱测和防控作用,可作为监测和防控斜纹夜蛾的有效措施推广应用。     

舞毒蛾性信息素应用技术的研究

1983—1986年应用舞毒蛾光学活性性信息素及其光学异构体的生物活性试验表明,顺-7,8-环氧-2-甲基-十八烷[(+)-(7R,8S)-disparlure]是舞毒蛾天然性信息素,诱蛾效果非常显著,而其它光学异构体基本无效。舞毒蛾性信息素不仅对舞毒蛾具有活性高,而且对松针毒蛾也具有活性。使用舞毒蛾性信息素作为测报工具,不仅可以监测舞毒蛾的发生,同时也可以监测松针毒蛾的发生。性信息素监测虫情,可以降低劳动强度,精确度高,方法简便易行。在低虫口地区,使用粘胶诱捕器进行大量诱捕法是成功的,连绩使用诱捕法即可有效的控制舞毒蛾的危害和蔓延,抑制其猖獗暴发的周期。在虫口密度大的地区,可先用杀虫剂压低虫口密度,再使用性信息素进行控制,使性信息素与化学防治相结合,减少化学农药的使用,有利于保护环境和害虫天敌,从而提高防治效果。舞毒蛾性信息素的应用,为该虫的防治开辟了一条新的途径,将成为综合治理舞毒蛾的有力工具之一。     

陌夜蛾性信息素类似物的合成及其生物活性

背景 陌夜蛾（Trachea atriplicis）作为一种重要食叶害虫，近年来，由于其数量以及危害程度的不断增加，已对我国华北、华东等地区的农林业造成重大危害，尤其是对荞麦等作物的产量构成严重威胁。目的 以陌夜蛾性信息素主要组分顺-11-十六碳烯乙酸酯（Z11-16:Ac）为母体结构，合成6种具有不同生物活性的性信息素类似物，为陌夜蛾的综合治理开辟一种新型环境友好的防治策略。方法 选用性信息素组分的前体顺-11-十六碳烯-1-醇（Z11-16:OH）为原料，在缚酸剂和催化剂的作用下，与酸酐或酰氯发生反应，通过硅胶柱层析进行分离纯化后，合成性信息素类似物共6种。包括极性基团为氨基甲酸酯的性信息素类似物M3、M4，极性基团末端引入不饱和键的性信息素类似物M5、M6，以及卤素原子修饰的性信息素类似物M7、M8。通过触角电生理试验（EAG）测定不同剂量性信息素类似物直接刺激下的EAG响应值，并于北京市延庆区进行田间试验对性信息素类似物的生物活性进行验证。结果 EAG试验表明，类似物M1、M2、M6、M7和M8具有显著的剂量-效应关系。其中陌夜蛾雄蛾触角对类似物M7的响应最为强烈，在100 μg剂量下响应值达2.36 mV，是同剂量条件下Z11-16:Ac响应值的77.9%。而M3—M5在10—1 000 μg剂量下，与性信息素组分Z11-16:Ac的相对响应值之间存在显著差异（P<0.05），M5的EAG响应整体活性表现较差，最高相对响应值仅为性信息素组分的21.2%。田间试验表明，类似物M1和M5在添加剂量为1 μg时，平均诱捕量分别为38.00和35.67头/诱捕器/15 d，与性信息素对照相比存在显著差异；类似物M7在添加剂量为100 μg时，平均诱捕量为29.67头/诱捕器/15 d，显著高于性信息素对照；类似物M4具有潜在的抑制活性，随着其添加剂量的增加，平均诱捕量逐渐减少，当添加剂量为1 000 μg时，平均诱捕量仅有3.33头/诱捕器/15 d。 结论经过EAG试验和田间试验验证，类似物M1、M5和M7具有显著的增效活性，可以用作性信息素的增效剂，类似物M4具有显著的抑制活性，可以用作性信息素的抑制剂。研究结果可为使用性信息素类似物绿色防控陌夜蛾提供理论依据。     

利用植物源引诱剂监测与控制舞毒蛾

在内蒙古阿尔山林业局兴安落叶松纯林内,选取受害兴安落叶松针叶的挥发物并复配成引诱剂（植物源引诱剂）,测定其对舞毒蛾成虫的引诱效果。试验一利用窗式诱捕器携带4种诱芯：1）植物源引诱剂（引诱剂I）,2）舞毒蛾性信息素（引诱剂Ⅱ）,3）前两者之结合（引诱剂Ⅲ）,4）空白对照于9块样地（幼、中龄林和成熟林各3块）进行测定。试验...     

Direct-current nanogenerator driven by ultrasonic waves

We have developed a nanowire nanogenerator that is driven by an ultrasonic wave to produce continuous direct-current output. The nanogenerator was fabricated with vertically aligned zinc oxide nanowire arrays that were placed beneath a zigzag metal electrode with a small gap. The wave drives the electrode up and down to bend and/or vibrate the nanowires. A piezoelectric-semiconducting coupling process converts mechanical energy into electricity. The zigzag electrode acts as an array of parallel integrated metal tips that simultaneously and continuously create, collect, and output electricity from all of the nanowires. The approach presents an adaptable, mobile, and cost-effective technology for harvesting energy from the environment, and it offers a potential solution for powering nanodevices and nanosystems.     

Sex pheromone of the winter moth, a geometrid with unusually low temperature precopulatory responses

The sex pheromone for the winter moth, Operophtera brumata (L.), has been identified as the novel compound (Z,Z,Z)-1,3,6,9-nonadecatetraene. The male moths respond to the pheromone at low temperatures (4 degrees to 15 degrees C) and exhibit an upper response limit that coincides with the lower response limit for other reported moth sex pheromone systems. The pheromone attracted two other geometrid species, O. bruceata (Bruce spanworm) and O. occidentalis.     

Disruption of sex pheromone communication in a nematode

Males of Nippostrongylus brasiliensis, an intestinal parasite of rodents, were maintained in an environment permeated with pheromone produced by females of the species. After the males were removed from that environment, their subsequent ability to orient to a gradient of the pheromone emanating from living females was greatly reduced for periods up to 2 hours. This phenomenon might serve as the basis for a new, selective antihelminthic technique in which the premating communication between males and females is disrupted.     

核桃举肢蛾性信息素通讯系统扫描电镜观察

通过对核桃举肢蛾雌蛾性腺(性信息素释放系统)和雄蛾触角(性信息素接受系统)表面进行扫描电镜观察,发现核桃举肢蛾性信息素分泌腺位于腹尖末端8~9节之间,为一个由节间膜特化而成的完整上皮环结构,性信息素感受器有毛形感器和刺形感器。核桃举肢蛾性信息素通讯系统的研究为核桃举肢蛾性信息素快速提取、分析、合成提供了依据。     

性诱剂监测及防治小菜蛾研究初报

 2009年1~8月,利用性诱剂对临沧市临翔区蔬菜小菜蛾进行了监测及防治研究。结果表明,性诱剂监测与测报灯监测相比,性诱剂监测更为灵敏,诱捕效果更好。小菜蛾发生高峰期在3月中下旬。性诱剂对小菜蛾防治效果可达60%~70%,随作用时间的延长控制效果愈加显著（P<0.05）。利用性诱剂可持续、有效地控制田间小菜蛾种群数量,减少农药的使用,具有经济、安全、高效的特点。性诱剂在小菜蛾的监测及防治上的应用前景极佳     

绵山天幕毛虫性信息素通讯系统扫描电镜观察

通过对绵山天幕毛虫性信息素释放系统——雌蛾性腺和性信息素接受系统——雄蛾触角进行扫描电镜观察,发现绵山天幕毛虫性信息素分泌腺位于腹尖末端8~9节之间,是一个可外翻的环状结构;性信息素感受器主要为毛形感器。绵山天幕毛虫性信息素通讯系统的研究为绵山天幕毛虫性信息素的快速提取、分析、合成提供了依据。     

Double flood basalts and plume head separation at the 660-kilometer discontinuity

Several of the world's flood basalt provinces display two distinct times of major eruptions separated by between 20 million and 90 million years. These double flood basalts may occur because a starting mantle plume head can separate from its trailing conduit upon passing the interface between the upper mantle and the lower mantle. This detached plume head eventually triggers the first flood basalt event. The remaining conduit forms a new plume head, which causes the second eruptive event. The second plume head is predicted to arrive at the lithosphere at least 10 million years after the first plume head, in general agreement with observations regarding double flood basalts.     

A Major Helium-3 Source at 15{degrees}S on the East Pacific Rise

An extensive plume of water enriched with helium-3 has been discovered in the deep Pacific Ocean at latitude 15 degrees S on the East Pacific Rise. In the core of the plume, at a depth of 2500 meters over the ridge crest, the helium-3/helium-4 ratio is 50 percent higher than the ratio in atmospheric helium, indicating a strong injection of mantle or primordial helium at the spreading center axis through local hydrothermal systems. The helium-3 plume is completely absent east of the rise, but it can be traced over 2000 kilometers to the west above a newly observed physical feature: a density discontinuity here caled the "ridge-crest front." The injected plume provides a unique deep-sea tracer with an asymmetric distribution which shows that the deep circulation across the rise is from east to west. The striking intensity and lateral extent of this helium-3 anomaly, compared to observations at known oceanic hydrohrmal sites, suggest that the largest hydrothermal fields in the ocean are yet to be discovered and that they will be found near 15 degrees S on the East Pacific Rise.     

梨小食心虫性诱剂效果评价

梨小食心虫(Grapholitha molesta Busck)是世界性的重要果树钻蛀性害虫之一。目前,性信息素诱捕器广泛应用于害虫防控,为提高性诱剂对梨小食心虫测报及诱捕效率,从两方面研究了梨小食心虫性诱剂对梨小食心虫的诱捕效果,采用了8个性诱剂产品诱杀梨小食心虫,同时每个诱捕器内设1、3、5、7、9、11个芯数,共6个处理诱杀梨小食心虫。结果表明,A诱捕性诱芯和C诱捕性诱芯诱捕效果最好;诱捕器的诱芯数量为1时引诱到的梨小食心虫数量最多。建议在田间测报和大量诱捕时,使用A诱芯,可达到较高诱捕量,同时也可节约成本,提高效率。