尺蠖性信息素的不对称合成研究进展

尺蠖是危害果树与林木的重要害虫,其性信息素的化学成分包括手性甲基烷烃、三烯烃与手性环氧烯烃3类化合物,可用于尺蠖的诱集与害虫预测。本文首先依据手性中心的构建方法,详细阐述了利用手性源法、酶拆分法、不对称催化法、螯合控制反应法与手性诱导法合成手性甲基烷烃类尺蠖性信息素的研究进展;然后按照中间体的连接方式,分类总结了烷基环氧重排法、炔基锂试剂取代法与Gilman试剂取代法合成手性环氧烯烃类尺蠖性信息素的研究工作。     

粉螨性信息素(R)-2,6-二甲基-5-庚烯-1-醇的不对称合成

粉螨Tyreophagus sp. 包括许多危害农作物的重要害虫和仓储害虫,而(R)-2,6-二甲基-5-庚烯-1-醇为粉螨 性信息素的主要成分。本研究首次利用Evans手性助剂法构建该性信息素的手性叔碳中心,以戊醛酸甲酯为原料,经过Wittig偶联、LiOH水解、甲基化及硼氢化钠还原等6步反应,完成了该信息素的不对称合成。     

不同色板及诱芯对黄曲条跳甲的诱集效果

为探讨不同颜色色板及色板加信息素诱芯在田间对黄曲条跳甲的引诱效果,在蔬菜种植地区利用蓝、绿、黄、白4种色板和聚集信息素诱芯对黄曲条跳甲进行田间诱集效果和种群监测。结果表明:4种色板中,绿板和黄板对黄曲条跳甲诱集效果较强,诱虫量高于白板和蓝板,蓝板诱集效果最弱。添加聚集信息素诱芯后,黄板和绿板处理组能明显提高色板对黄曲条跳甲的诱集数量。今后可选择黄板和绿板,同时结合使用聚集信息素诱芯可实现十字花科蔬菜上黄曲条跳甲种群数量的诱集监测和预测预报。     

美国白蛾性信息素的合成研究进展

美国白蛾是世界性检疫害虫，其性信息素包括2个烯醛类化合物与3个环氧烯烃类化合物，可用于诱集美国白蛾，监测种群动态，具有优异的应用前景。本文根据醛的合成方法，阐述了仿生合成法、Weinreb酰胺法、酶催化法、酯的硅氢化等合成烯醛类美国白蛾性信息素的方法；依据关键中间体的连接方式，总结了异硫氰酸铜试剂法、Wittig偶联法、炔基锂试剂取代法、Gilman试剂取代法及烷基环氧重排法等合成环氧烯烃类美国白蛾性信息素的方法。     

蓟马信息素研究及应用进展

蓟马是农作物和园艺作物上常见的重要害虫,其通过直接取食和间接传播病毒给作物造成了巨大的经济损失。应用蓟马信息素是蓟马害虫绿色防控的重要措施。本文综述了蓟马产生的信息化学物质的研究进展,概述了已报道的蓟马肛门分泌物的化学组分及其功能,介绍了已鉴定的蓟马报警信息素、聚集信息素、接触信息素和抑性欲信息素的主要成分、分泌部位、作用功能和合成方法,讨论了信息素在蓟马害虫防控中的应用潜能,并展望了目前蓟马信息素研究中存在的问题和未来的发展方向,以期为蓟马害虫信息素的合理应用提供指导。     

梨小食心虫性信息素主要成分的化学合成与田间活性试验

探索梨小食心虫性信息素主要成分的合成方法,为梨小食心虫的田间迷向防治提供化合物。梨小食心虫性信息素主要成分是顺-8-十二碳烯乙酸酯(Z8-12:Ac)、反-8-十二碳烯乙酸酯(E8-12:Ac)、顺-8-十二碳烯-1-醇(Z8-12:OH)。以1,8-辛二醇和正丁醛等为起始原料,以二甲基亚砜为溶剂,通过Wittig反应合成目标化合物Z/E8-12:OH,顺反比例为94﹕6,产率达42.5%,通过红外、GC、NMR、MS进行鉴定。以合成的性信息素主要成分制备散发器(迷向芯),在桃园进行田间迷向试验。结果表明,自主合成的产物对梨小食心虫有良好的迷向作用。     

昆虫类信息素研究进展及应用前景

昆虫信息素具有微量、高效、无毒、不伤害天敌、不污染环境等优点,在害虫综合治理中发挥着重要作用。然而,天然信息素的高挥发性和在空气快速氧化以及合成成本高等问题限制了其在害虫综合治理中的实际应用。与天然信息素相比,昆虫类信息素具有更好的物理、化学和毒理性等优点,可以弥补天然信息素的不足,现已成为国内外的研究焦点。本研究对昆虫类信息素的概念与类型、研发与合成、特性及应用前景等方面进行归纳总结,阐述了利用昆虫类信息素在害虫综合治理上的研究状况,并展望了其应用前景。     

黄板对菜地黄曲条跳甲的诱杀试验

在十字花科蔬菜地中用黏性黄板可诱捕到菜蚜、黄曲条跳甲、美洲斑潜蝇、稻飞虱、叶蝉等害虫,其中对黄曲条跳甲成虫具有良好的诱杀效果.黄板的悬挂高度以黄板底边低于菜株顶部5cm或与菜株叶片顶部持平,对黄曲条跳甲成虫诱杀效果最佳,每日以11～15时诱虫量最多.黄板诱杀可以作为防治黄曲条跳甲的1种有效措施.     

昆虫性信息素在蔬菜害虫监测中的应用初探

通过利用昆虫性信息素对斜纹夜蛾、小菜蛾、甜菜夜蛾等蔬菜害虫成蛾采用不同设置方法在田间、市区内不同高度等地点进行全年性的系统诱捕调查试验,并与这3种害虫的田间发生消长情况进行比较,结果证明昆虫性信息素专化性强,诱蛾效果明显,且诱蛾情况与田间害虫发生消长情况相吻合.利用昆虫性信息素对蔬菜害虫进行系统监测能及时掌握害虫在田间各时期的发生消长动态,且操作方便,可以作为蔬菜害虫监测上的一种重要手段,以达到提高蔬菜害虫测报准确率、减少测报工作人员的调查工作量的目的.     

植物源甘油酯与金龟子绿僵菌对黄曲条跳甲的室内毒力及田间防效评价

黄曲条跳甲Phyllotreta striolata是为害十字花科蔬菜的重要害虫,长期使用大量的化学农药,不仅增强了黄曲条跳甲的耐药性,也会导致蔬菜农药残留增加,危害人们的饮食健康。因此,利用绿色防控手段防治害虫成为近些年的研究热点。本文在室内测定了以植物源甘油酯为主要成分的植物油乳剂、绿僵菌以及二者混配液对黄曲条跳甲成虫的毒力并对油菌混配液的田间防控效果进行了评价。室内毒力测定结果表明,施用植物油乳剂50～800倍液时,黄曲条跳甲成虫第2 d的死亡率为37.93%～100%;施用绿僵菌1.25×10⁷～2×10⁸孢子/mL时,黄曲条跳甲成虫第5 d的死亡率为32.2%～93.22%;施用植物油乳剂和绿僵菌混配液时,黄曲条跳甲成虫第1 d的死亡率在95%以上,显著高于2种单剂,且混配液能够极显著缩短黄曲条跳甲致死中时。田间试验结果表明,以植物油乳剂100倍液和绿僵菌1×10⁸孢子/mL混配处理第6 d时,黄曲条跳甲成虫的相对防效和虫口减退率均达60%以上,第8 d时,黄曲条跳甲成虫的相对防效和虫口减退率分别为89.80%和74.62%,显著高于同时间同浓度2种单剂。本研究结果表明植物源甘油酯乳剂和绿僵菌在防治黄曲条跳甲方面具有显著的协同增效作用,二者混合使用可以弥补各自的防治缺点并有效地防治黄曲条跳甲。为探究和利用生物源农药之间的协同增效作用防控害虫提供了实用案例。     

Temporal Dynamics of Corn Flea Beetle Populations Infested with Pantoea stewartii, Causal Agent of Stewart's Disease of Corn

ABSTRACT In order to better understand the epidemiology of the Stewart's disease of corn pathosystem, quantitative information concerning the temporal dynamics of the amount of pathogen inoculum present in the form of Pantoea stewartii-infested corn flea beetles (Chaetocnema pulicaria) is needed. Temporal changes in the proportion of P. stewartii-infested corn flea beetle populations were monitored by testing individual corn flea beetles for the presence of P. stewartii using a peroxidase-labeled, enzyme-linked immunosorbent assay. Approximately 90 corn flea beetles were collected each week from seven locations in Iowa from September 1998 through October 2000 using sweep nets. The proportion of P. stewartii-infested beetles at the end of the 1998 growing season ranged from 0.04 to 0.19. In spring 1999, the proportion of overwintering adult corn flea beetles infested with P. stewartii ranged from 0.10 to 0.11 and did not differ significantly from the previous fall based on chi(2). During the 1999 corn-growing season, the proportion of infested corn flea beetles ranged from 0.04 to 0.86, with the highest proportions occurring in August. In fall 1999, the proportion of beetles infested with P. stewartii ranged from 0.20 to 0.77. In spring 2000, the proportion of overwintering adult corn flea beetles infested with P. stewartii ranged from 0.08 to 0.30; these proportions were significantly lower than the proportions observed in fall 1999 at Ames, Chariton, and Nashua. During the 2000 corn-growing season, the proportion of P. stewartii-infested corn flea beetles ranged from 0.08 to 0.53, and the highest observed proportions again occurred in August. Corn flea beetle populations sampled in late fall 2000 had proportions of infested beetles ranging from 0.08 to 0.20. This is the first study to quantify the temporal population dynamics of P. stewartii-infested C. pulicaria populations in hybrid corn and provides new quantitative information that should be useful in developing risk models to predict the seasonal and site-specific risks associated with Stewart's disease of corn.     

光周期对莲草直胸跳甲生长发育和繁殖的影响

为明确莲草直胸跳甲Agasicles hygrophila Selman et Vogt的生态适应性,提高其对恶性杂草喜旱莲子草Alternanthera philoxeroides(Martius)的生物防治效率,研究了7组不同光周期对其生长发育和繁殖的影响。结果表明:不同光周期处理下,莲草直胸跳甲卵的孵化历期差异显著,在L∶D=12 h∶12 h时孵化历期最短,为4.33 d;其化蛹率无显著差异。相较于短光期,长光期条件更适合其幼虫生长发育。随着光照时数的增加,莲草直胸跳甲成虫寿命、产卵历期、雌虫产卵量呈明显单峰趋势,光周期为L∶D=12 h∶12 h时,成虫寿命和产卵历期最长,分别为41.8 d和34.0 d;光周期为L∶D=8 h∶16 h时,雌虫产卵量最高,为98.5块。不同光周期处理下其成虫后代的孵化率均高于85%,各处理间均无显著差异。在7组光周期处理下,莲草直胸跳甲均未出现生长与生殖停滞及大量死亡现象。生命表分析结果显示,光周期为L∶D=12 h∶12 h时,莲草直胸跳甲种群的净增殖率、平均世代周期及内禀增长率均最高,分别为386.88、45.36和0.13;而种群增殖时长最短,为5.27 d。表明光周期为L∶D=12 h∶12 h时最适合莲草直胸跳甲生长发育和繁殖。     

Epitrix pubescens can cause damage to potato (Solanum tuberosum)

Potato (Solanum tuberosum) has not been recorded as a host of Epitrix pubescens (Koch, 1803), a species of flea beetle present in Europe. However, anecdotal evidence was received of damage to potato leaves caused by flea beetles observed during inspections of potato crops and also on potato plants within a garden in France. Although potato may not act as a host for all life stages of this beetle, adults may feed on foliage and cause foliar symptoms similar to those caused by non‐native Epitrix species.     

Identification and pest status of two exotic flea beetle species newly introduced in Portugal: Epitrix similaris Gentner and Epitrix cucumeris (Harris)

Around 2004, a new type of injury was noticed in potato tubers harvested in the north of Portugal. Two North American flea beetles, Epitrix cucumeris and Epitrix similariswere later identified. The second species seems to be responsible for the characteristic type of tuber injury observed. The main morphological characters enabling the two species to be distinguished are presented.     

Plant volatile aldehydes as natural insecticides against stored-product beetles

BACKGROUND: Infestation by stored-product pests causes serious losses in food and feed commodities. Among possible strategies against these pests, which aim to reduce the use of synthetic insecticides, including fumigants, natural insecticides produced by plants represent one of the most promising approaches for their ecochemical control. Three six-carbon and nine-carbon aldehydes, natural plant volatiles produced by the plant lipoxygenase pathway, were tested for their insecticidal activity against five species of stored-product beetles in feeding, fumigation and combined bioassays. RESULTS: The compounds (2E,6Z)-nonadienal, (2E)-nonenal and (2E)-hexenal were incorporated into feeding discs in feeding bioassays or evaporated from filter paper in closed glass chambers in fumigation tests. Beetle sensitivity to aldehydes differed according to the different treatments. The highest activity was obtained by (2E)-hexenal in fumigation tests, with the LC(50) ranging from 4 to 26 mg L(-1), while (2E, 6Z)-nonadienal was the most effective in feeding tests, giving LD(50)s ranging from 0.44 to 2.76 mg g(-1) when applied to feeding discs. Fumigation tests in the presence of wheat grains confirmed that (2E)-hexenal was the most effective compound, with a calculated LC(99) ranging from 33 to 166 mg L(-1). CONCLUSION: The results of both feeding and fumigation tests indicated that natural plant aldehydes are potential candidates to control stored-product beetles.     

Effects of organic and synthetic fertilizer sources on pest and predatory insects associated with tomatoes

The effects of organic (composted cow manure) and synthetic (NPK) fertilizers on pests (aphids and flea beetles) and predatory arthropods (anthocorids, coccinellids and chrysopids) associated with tomatoes were evaluated in a 2-year randomized complete block field experiment. Our data suggested that the application of either organic or synthetic fertilizers could increase pest populations on tomatoes. However, there were lower populations of aphids on tomatoes grown with the organic fertilizer than on those grown with the synthetic fertilizers in the second year of the experiment, indicating that organic fertilizers may have the potential to reduce pest attacks in the long term. Anthocorid populations were larger on tomato plants with high aphid populations in the synthetic than in the organic fertilizers-treated plots. http://www.phytoparasitica.org posting July 6, 2003.     

Note: New records of flea beetle (Coleoptera: Chrysomelidae) from Turkey

Five species of flea beetles (Coleoptera: Chrysomelidae) were recorded for the first time in Turkey:Dibolia numidica Doguet,Longitarsus corynthius corynthius (Reiche et Saulcy),L. onosomae (Peyerimhoff),L. pulmonariae Weise andPhyllotreta ganglbaueri Heikertinger. The zoogeographical distribution of the species was reviewed. Among the species,L. onosmae andD. numidica have a limited distribution area in North Africa, and therefore their presence in Turkey is interesting. http://www.phytoparasitica.org posting July 14, 2004.     

硝酸银-硅胶分离技术及其在昆虫信息素研究中的应用

硝酸银-硅胶分离属络合层析技术,多用于含双键化合物的分离纯化。与常规硅胶柱层析分离法相比,硝酸银-硅胶技术在分离烯烃、不饱和醇、醛和酯类昆虫信息素等领域具有明显优势。本文介绍了硝酸银-硅胶分离技术的特点、操作方法及影响分离效果的因素,总结了硝酸银-硅胶分离技术在昆虫信息素研究中的应用,以及适用此分离技术的昆虫信息素的结构特点,可为更高效、更简便地分离昆虫信息素成分提供参考。     

The adverse impact of the neonicotinoid seed treatment ban on crop protection in oilseed rape in the United Kingdom

This paper describes the consequences of the ban on neonicotinoid seed treatments on pest management in oilseed rape. Since the ban was implemented in December 2013, there have been serious crop losses in 2014, 2015 and 2016 owing to cabbage stem flea beetles, Psylliodes chrysocephala, and aphids, Myzus persicae, which have developed resistance to the alternative pyrethroid sprays that were employed to control them. This has resulted in increased crop losses, decreased yields and a substantial decrease in the area grown, leading to fewer flowering crops available in the spring, especially in the eastern region of the United Kingdom. This is likely to have an adverse effect on bees locally. © 2016 Society of Chemical Industry     

古尔班通古特沙漠南缘拟步甲的物种多样性

于2010年5-7月利用陷阱法抽样技术,调查研究了古尔班通古特沙漠南缘不同生境中拟步甲的活动密度和群落多样性。结果表明：① 在景观尺度上,拟步甲科的物种多样性整体比较低,活动密度、物种丰富度、多样性指数、优势度指数等群落特征值在不同景观间变化显著,拟步甲更倾向于分布在荒漠边缘;② 拟步甲科多数优势种对微生境的选择表现出明显的倾向性,同属物种对微生境的选择表现出类似的倾向性;③ 重大农业工程的干扰,使得物种丰富度和均匀度指数有所下降,但差异不显著。多样性指数的下降及优势度指数的升高达到显著水平(P<0.05);不同物种的活动密度均表现为下降(库氏东鳖甲和光滑胖漠甲除外)。表明拟步甲对荒漠生境有指示意义。