液体或固体培养对环链棒束孢(Isaria cateinannulata)菌丝体中挥发性成分组成的影响

[目的]测定环链棒束孢(Isaria cateinannulata)在不同培养方式下,其菌丝中挥发性代谢物组成,分析代谢产物差异与培养方式间的相互联系.[方法]分别用SDAY培养基固体平板与SDY培养基液体摇瓶的培养方式进行培养;培养温度为25℃,培养周期为8天;用同时蒸馏萃取装置提取菌丝的挥发性成分;用气质联用仪进行数据采集及分析.[结果]固体培养菌丝体含有较多种类的挥发性成分,共鉴定41种化合物,其中酯类、醌类和肟类化合物为其特有.液体培养菌丝体含有的挥发性成分相对较少,共鉴定32种化合物,其中羧酸类化合物为其特有,同时酚类含量远高于固体菌丝.固体和液体培养菌丝体的主要挥发性成分都是烃类物质,其中烯烃类物质分别占固体培养菌丝和液体培养菌丝总挥发物的57.6％和7.85％,烷烃类物质分别占固体培养菌丝和液体培养菌丝总挥发物的9.19％和22.4％.[结论]固体或液体培养条件对环链棒束孢菌丝体中挥发性成分的组成有影响.     

罗汉果花气味物质量化分析方法研究

罗汉果(Siraitia grosvenorii)是葫芦科著名的药食两用植物,广泛种植于广西桂林地区,其开花后传粉不良现象迫切需要研究解决。为了探讨罗汉果花朵气味物质与传粉者访花频率的关系以及查明传粉不良产生的原因,该文选择罗汉果雄花为材料,研究了罗汉果花朵气味物质的量化分析方法。实验采用动态顶空吸附法收集新鲜花朵的气味物质,经过洗脱、洗脱液吹氮和GC-MS分析等步骤,先后完成了花朵气味物质的收集、浓缩、分离和鉴定,最后以峰面积归一化法计算各化学组分的相对含量。结果表明:从供试花朵中检测到挥发性组分(包括萜烯类物质) 5种,以及芳香烃类、烷烃类、酯类物质各1种,其中萜烯类物质的相对含量达71.07%,是供试花朵最主要的挥发性化合物。该结果高度符合葫芦科植物花朵气味的化学组分特征,并具有良好的实验重复性,表明该实验体系是收集和鉴定罗汉果花朵气味组分的理想方法,为后续开展罗汉果花气味物质研究奠定了重要基础。同时通过与葫芦科多种植物比较,发现罗汉果的花朵气味物质可能存在雌雄二型性。     

9 种海洋硅藻挥发性成分的比较分析

采用顶空固相微萃取气相色谱一质谱联用技术,通过SIMCA．P分析软件,对硅藻门下处于生长平台后期的9种海洋硅藻的挥发性成分进行比较分析研究。结果表明：在平台后期硅藻的挥发性成分中,醛类物质的含量和种类占据了很大的优势,壬醛、2,4-辛二烯醛、2-己烯醛、2-壬烯醛、2,4-庚二烯醛等是硅藻挥发性成分的主要构成物质,十四烷、十五烷、1-十五烯、十六烷等烷烃类是硅藻中含量仅次于醛类物质的挥发性成分,3,5-辛烯基-3-酮等短链酮类和1-辛烯基-3-醇是硅藻中含量较高的酮类和醇类物质,9种硅藻中均检测二甲基硫的存在。差异性较大的挥发性物质主要有壬醛、8-十七碳烯、1-戊烯．3．酮、1-己烯-3．醇、2,6-二甲基一苯酚,它们决定了不同的硅藻有着各自不同的风味。研究结果表明这些挥发性物质对硅藻的饵料价值、养殖生物的肉质风味、水环境的异味形成有着重要意义。     

基于HS-SPME和GC-MS联用技术测定不同种泡桐花挥发性成分CSCD

本文采用顶空固相微萃(HS-SPME)和气相色谱-质谱(GC-MS)联用技术测定白花泡桐、兰考泡桐、楸叶泡桐、毛泡桐和白花泡桐天然杂种花中的挥发性成分,分析不同种间挥发性成分组成和相对含量,并对其进行聚类和主成分分析。结果表明,5个不同种泡桐花中共鉴定出45种挥发性物质,主要包括12种萜类、8种醇类、7种酯类、3种酚类、6种醛类、2种木脂素、2种苯类、2种酮类、2种烷烃和1种醚类共10类物质;5个泡桐种共有挥发性组分7种,包括1种萜类、2种醇类、1种酯类、2种酚类、1种酮类,且其特有物质分别为9、1、4、3、0种;5个泡桐种均以醇类化合物的相对含量最高,且醇类化合物中均以1-辛烯-3-醇和3-辛醇的相对含量较高;聚类分析结果表明楸叶泡桐和毛泡桐相似性较高,而白花泡桐与其他种泡桐相似性均较低;第一主成分(PC1)和第二主成分(PC2)之和为70.7%,PC1的主要贡献物质为酯类、烷烃、萜类、醚类、酮类、醇类和苯类,PC2的主要贡献物质为酚类、醇类、醛类、酮类、醚类、苯类和木脂素;偏最小二乘法-判别分析(PLS-DA)筛选出1-辛烯-3-醇、1,2,4-三甲氧基苯和顺式茴香烯等11种标志性差异挥发性成分。本研究可为不同种泡桐花挥发性成分的精准评价及高效利用提供参考依据。     

受损芥蓝挥发性物质昼夜释放节律的初步研究

采用固相微萃取采集吸附、热脱附及GC-MS分析的方法,对芥蓝受小菜蛾侵害后释放的挥发性物质的组成及昼夜释放节律变化进行了研究.小菜蛾取食后的芥蓝挥发性物质释放量是未受损的芥蓝的一倍,同时检测到较多的挥发性物质种类.受小菜蛾取食后的芥蓝,分子量小的挥发性物质的种类和数量增加.昼夜释放节律研究表明,正常芥蓝的不同的挥发物表...     

水生植物轮藻特殊气味的分析研究

本实验采用热脱附气质联用技术(TCT-GC/MS)对山西省内三种轮藻的挥发性气味的化学成分(VOCs)进行了分析,共鉴定出43种物质,主要为烷烃类、酮类、醇类等物质,其中野生不连续轮藻、实验室培养的不连续轮藻和普生轮藻的挥发性物质组成基本相似,以烷烃类为主,而钝节拟丽藻的气味组成与它们存在较大差异,说明其存在属间差异;在轮藻的VOCs组成中,发现了苯并噻唑、青叶醛、α-蒎烯和为薄荷烯等有记载的对昆虫起趋避和杀灭作用的化合物,所以轮藻应具有杀虫活性;另外还在其VOCs组成中发现了苯系物的存在,说明轮藻对其有吸附作用,但这种吸附作用同样存在属间差异。     

一种热稳定的人胎盘源促细胞生长因子

胎盘细胞中含有丰富的生物学活性物质.通过在 90℃温度下酸性介质抽提、乙醇沉淀、DE-52阴离子交换层析、高效液相色谱层析,从人胎盘组织中分离纯化得到一种热稳定的小分子量促细胞生长因子.该物质对人羊膜细胞、小鼠成纤维细胞、小鼠骨髓瘤细胞等多种细胞有较高的刺激生长活性.这种物质被称为人胎盘源促细胞生长因子Ⅰ(Human Placental Growth Factor-I,简称HPGF-1),它是一种分子量为1900的肽类物质,是由一条含有10个氨基酸残基的肽链和非肽部分组成的化合物.肽链部分的分子量为1195,其氨基酸组成已被测定,N-末端残基为 Phe.非肽部分的分子量为692. 该因子的等电点为6.8.     

固相微萃取-气相色谱-质谱结合电子鼻技术分析发酵乳中挥发性风味物质

【背景】德氏乳杆菌保加利亚亚种(Lactobacillus delbrueckii subsp. bulgaricus)和嗜热链球菌(Streptococcus thermophilus)作为酸奶的常用发酵剂,在乳制品生产中的应用十分广泛。【目的】在前期研究基础上,以筛选出的具有良好风味的复配发酵剂(复配比为1:100)L.delbrueckiisubsp.bulgaricusIMAU20312与S.thermophilusIMAU80809为实验对象,分析牛乳在发酵及贮藏期间风味物质的动态变化规律,为发酵剂的开发与应用提供依据。【方法】采用固相微萃取-气相色谱-质谱联用(solid-phasemicroextraction-gaschromatography-mass spectrometry, SPME-GC-MS)结合电子鼻技术检测并解析新鲜牛乳在发酵及贮藏阶段所产生的挥发性风味物质。【结果】该发酵剂在牛乳发酵及贮藏期间产生酸类物质23种,醛类物质13种,醇类物质15种,酮类物质18种,酯类物质11种,烷烃类物质22种。香气活度值(odor activity value, OAV...     

植物挥发性次生物质在植食性昆虫、寄生植物和昆虫天敌关系中的作用机理

植物挥发性次生物质在植食性昆虫、寄生植物和昆虫天敌关系中的作用机理杜永均,严福顺（中国科学院动物研究所,北京１０００８０）植物挥发性次生物质是一些分子量在１００—２００的有机化学物质,包括烃类、醇类、醛类、酮类、有机酸、内酯、含氮化合物以及有机硫等化...     

光肩星天牛幼虫虫粪挥发物成分分析

天牛幼虫排出的虫粪所释放的挥发性物质成为天敌搜寻天牛所在微栖境的重要化学信息物质.本试验采用固相微萃取技术,提取光肩星天牛Anoplophora glabripennis(Motschulsky)取食垂柳和金丝柳后产生虫粪的挥发性物质,利用气相色谱-质谱联用仪(GC-MS)进行鉴定.结果表明,虫粪挥发性物质主要为萜烯类物质.两种虫粪挥发物中含共有物质19种,其中à-蒎烯的含量最高,该物质在垂柳虫粪挥发物中相对含量为51.60%,在金丝柳虫粪中的相对含量为28.84%.在金丝柳虫粪中检测到的挥发物种类稍多于垂柳虫粪中检测到的种类.     

外源茉莉酸诱导植物反应对菜蛾绒茧蜂寄生选择行为的影响

茉莉酸是植物体内重要的伤信号分子,向植物施用外源茉莉酸后, 可诱导植物产生各种防卫反应, 如挥发物组成发生改变等, 进而影响植食性昆虫及其天敌。该文报道用不同浓度外源茉莉酸处理白菜和甘蓝后,诱导植物反应所产生的挥发物对菜蛾绒茧蜂搜索及寄生选择行为的影响。外源茉莉酸处理白菜和甘蓝后,处理植株的挥发物对菜蛾绒茧蜂的引诱力增强;与在对照植株上相比,该蜂对经茉莉酸处理后白菜植株上的小菜蛾幼虫的寄生数显著要高。表明茉莉酸处理白菜及甘蓝后,植物诱导反应导致其挥发物的作用发生变化,进而可提高该蜂的搜索和寄生效率。     

Effects of two neem insecticide formulations on the attractiveness, acceptability and suitability of diamondback moth larvae to the parasitoid, Diadegma mollipla (Holmgren) (Hym., Ichneumonidae)

Abstract:  Behavioural responses of female Diadegma mollipla to volatiles from cabbage plants and host-infested [ Plutella xylostella (L.)] cabbage plants sprayed with two neem insecticide formulations were investigated in a Y-tube olfactometer. Parasitoids were significantly more attracted to volatiles from cabbage and host-infested cabbage sprayed with the powder formulation than to clean air. In contrast, parasitoid response to volatiles from cabbage and host-infested cabbage sprayed with the oil formulation was not significantly different from clean air. In choice tests between infested plants sprayed with water (control) or the powder formulation, parasitoids showed no preference for volatiles from either of the treatments. In similar tests with the oil formulation, parasitoids showed a preference for volatiles from control plants over plants sprayed with the oil formulation. In host acceptance and suitability tests, parasitism rates in the neem- and water-sprayed hosts were, with one exception, not significantly different. However, the neem-sprayed larvae died earlier than control larvae and were therefore not able to support parasitoid development. The implication of these findings for the combined use of neem insecticides and parasitoids in the management of P. xylostella is discussed.     

小菜蛾幼虫对不同寄主的取食嗜好性及其适宜性

对不同寄主种类、不同寄主形态和不同寄主饲喂的小菜蛾(Plutella xylostella)幼虫之间的取食嗜好性比较试验表明,小菜蛾幼虫优先取食大白菜、萝卜或菜心幼苗,其次为油菜和甘蓝幼苗,在大白菜与油菜幼苗之间的取食选择比例是93.33%和6.67％;在甘蓝与菜心幼苗之间的取食选择比例是16.67%和83.33%.小菜蛾幼虫的取食嗜好性受饲喂寄主种类的影响,偏食大白菜或菜心幼苗.小菜蛾幼虫选择寄主取食的次序与寄主体内可溶性糖或淀粉含量没有明显关系,但与两者的相对量呈一定的负相关.取食大白菜或菜心幼苗的小菜蛾生长良好,单头取食达0.583～0.637 cm², 单头体重达2.07～2.18 mg, 与取食甘蓝或油菜幼苗的幼虫在取食量、个体发育方面有明显差异.小菜蛾幼虫也喜好取食已经被虫危害过的幼苗.     

Differential parasitism of Plutella xylostella (Lepidoptera: Plutellidae) larvae by the parasitoid Cotesia plutellae (Hymenoptera: Braconidae) on two host plant species

Laboratory experiments were conducted to examine host selection by Cotesia plutellae Kurdjumov when larvae of its host, Plutella xylostella (Linnaeus), fed on Chinese cabbage, Brassica campestris L. ssp. pekinensis and those fed on common cabbage, Brassica oleracea L. var. capitata were provided simultaneously, and to investigate the roles of plant and host volatiles in mediating host selection. When C. plutellae were provided with equal numbers of host larvae on plants of the two species in one arena, the parasitoid parasitized 4- to 15-fold more host larvae on Chinese cabbage than on common cabbage. This preference changed little with host density. However, an experience of searching coupled with an oviposition in a host larva on a leaf of the less-preferred plant, common cabbage, significantly increased the preference for parasitizing host larvae on this plant and resulted in twice as many host larvae parasitized on this plant than on Chinese cabbage. Dual choice tests with a Y-tube olfactometer showed that plant volatiles from Chinese cabbage were more attractive to female C. plutellae than those from common cabbage when plants of both species were either intact or infested. In parallel to the increased parasitism on common cabbage following experience, oviposition in a host larva on this less-preferred plant significantly increased the response to volatiles emanating from that plant. These results indicate that host plants may strongly influence the foraging behaviour of C. plutellae, but their differential attractiveness to the parasitoid may be altered by experience of the parasitoid.     

Laboratory evaluations of a wild crucifer Barbarea vulgaris as a management tool for the diamondback moth Plutella xylostella (Lepidoptera: Plutellidae)

The term 'dead-end trap cropping' has recently been proposed to identify a plant that is highly attractive for oviposition by an insect pest, but on which offspring of the pest cannot survive. The potential of the wild crucifer Barbarea vulgaris R. Br. to allure and serve as a dead-end trap crop for the diamondback moth Plutella xylostella (L.), an important pest of cruciferous crops worldwide, was examined in laboratory experiments. When P. xylostella adults were provided with a dual-choice of plants of B. vulgaris, and Chinese cabbage Brassica campestris (L.), in one arena, adult moths laid 2.5-6.8 times more eggs on the former than on the latter. When P. xylostella adults were provided with a dual-choice of plants of B. vulgaris and common cabbage Brassica oleracea L., adult moths laid virtually all their eggs on the former and ignored the latter. Nearly all P. xylostella eggs laid on the three species of plants hatched successfully, but nearly all individuals on plants of B. vulgaris died as neonates or early instar larvae, while 87-100% of the larvae on Chinese cabbage and common cabbage survived to pupation. Dual choice tests with a Y-tube olfactometer showed that volatiles from B. vulgaris were much more attractive to P. xylostella adults than those from common cabbage. The results demonstrate that B. vulgaris has a great potential as a dead-end trap crop for improving management of P. xylostella. Factors that may influence the feasibility of using B. vulgaris as a trap crop in the field are discussed, and ways to utilize this plant are proposed.     

上海青对小菜蛾取食胁迫的生理反应(英文)

上海青遭受小菜蛾取食为害后 ,0 .5小时内叶片的超氧化物歧化酶 (SOD)、过氧化氢酶 (CAT)、过氧化物酶 (POD)、多酚氧化酶 (PPO)和总酚含量发生变化。就一天内的变化趋势而言 ,受害叶片的SOD、CAT、POD、PPO活力和总酚含量总体上比正常叶片低。但在 1 5:0 0时 ,正常叶片的SOD、CAT和POD活力最低时 ,受害叶片这三种酶的活力却明显上升 ;在 1 1 :0 0时 ,正常叶片的PPO活力为最低值时 ,受害叶片的PPO活力却上升至最高。这可能是由于小菜蛾取食对叶片的过度胁迫造成的结果。正常叶片的PPO活力与总酚量为负相关 ,但受害叶片没有这种关系 ,可见小菜蛾取食还引起了青菜生理的紊乱。受害植株的未受害叶的酶活力也不同程度地发生变化 ,可见上海青对小菜蛾的取食胁迫的应激生理反应是系统性的。总而言之 ,当上海青的直接防御体系被小菜蛾破坏时 ,上海青可能有其它防御小菜蛾的机制     

小菜蛾取食后上海青的保护酶活力变化

上海青遭受小菜蛾取食为害后,0.5小时内叶片的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)、多酚氧化酶(PPO)和总酚含量发生变化。就一天内的变化趋势而言,受害叶片的SOD、CAT、POD、PPO活力和总酚含量总体上比正常叶片低,但在15：00时,正常叶片的SOD、CAT和POD活力最低时,受害叶片的三种酶活力却明显上升,在11：00时,正常叶片PPO活力为最低值时,受害叶片的PPO活力达最高,这可能是过度胁迫造成的,正常叶片的PPO活力与总酚量负相关,但受害叶片不呈现这种关系,此外,受害植株的未受害叶的保护酶活力也不同程度地发生变化,可见上海青对小菜蛾的取食胁迫后保护酶的反应是系统性的。     

亚麻荠对小菜蛾幼虫取食和成虫行为反应的影响

亚麻荠是一种很少有害虫危害的油料作物。用室内生测和Y 型嗅觉仪研究了亚麻荠对小菜蛾Plutella xylostella幼虫取食和成虫行 为反应的影响。以甘蓝作对照,用亚麻荠叶片喂养的小菜蛾初孵幼虫3天后校正死亡率为79 .2%,显示了较强的致死作用;喂养小菜蛾3龄幼虫至化蛹,其存活率、化蛹率、蛹重及成 虫寿命都显著降低,表明亚麻荠对小菜蛾幼虫的生长发育有不利影响。在幼虫的取食选择实 验中,有甘蓝叶供选择时,小菜蛾幼虫不取食亚麻荠;在无可选择的情况下,小菜蛾幼虫也 取 食亚麻荠叶片,但取食量很小,与取食甘蓝叶的量相比,差异极显著。行为反应测试表明, 小菜蛾成虫对甘蓝和亚麻荠植株的挥发物都有明显的趋性反应,与对照（净化空气）相比, 差异极显著,而在甘蓝和亚麻荠之间无选择性。说明小菜蛾成虫对亚麻荠植株的挥发物具有 较强的定向反应。     

Effects of specialist parasitoids on oviposition preference of phytophagous insects: encounter–dilution effects in a tritrophic interaction

Abstract.  1. Host plant preferences of the female diamondback moth Plutella xylostella were studied.
2. Female moths preferred conspecific-damaged cabbage plants over undamaged cabbage plants. The performance of P. xylostella larvae on conspecific-infested plants did not differ significantly from that of larvae on undamaged plants.
3.  Cotesia plutellae , the specialist parasitoid wasp of P. xylostella larvae, displayed equal preference for plants with differing levels of host-larvae damage, and the wasp attacked only one or two hosts on average before leaving an infested plant, irrespective of the number of hosts on the plant. It is hypothesised that the oviposition preferences of P. xylostella females for host plants already damaged by conspecific larvae demonstrate an encounter–dilution effect against C. plutellae .     

Non-host plant extracts reduce oviposition of Plutella xylostella (Lepidoptera: Plutellidae) and enhance parasitism by its parasitoid Cotesia plutellae (Hymenoptera: Braconidae)

Botanical preparations, usually from non-host plants, can be used to manipulate the behaviour of insect pests and their natural enemies. In this study, the effects of extracts of Chrysanthemum morifolium, a non-host plant of the diamondback moth, Plutella xylostella (Linnaeus), on the olfactory and oviposition responses of this phytophagous insect and on levels of parasitism by its specialist parasitoid Cotesia plutellae (Kurdjumov) were examined, using Chinese cabbage Brassica campestris L. ssp. pekinensis as the test host plant. Olfactometer tests showed that volatiles of chrysanthemum extract-treated host plants were less attractive to P. xylostella females than those from untreated host plants; and in contrast, volatiles of the chrysanthemum extract-treated host plants were more attractive to females of its parasitoid C. plutellae than those from untreated host plants. Oviposition preference tests showed that P. xylostella females laid only a small proportion of their eggs on chrysanthemum extract-treated host plants, while ovipositing parasitoid females parasitized a much higher proportion of host larvae feeding on the treated host plants than on untreated host plants. These results suggest that certain non-host plant compounds, when applied onto a host plant, may render the plant less attractive to a phytophagous insect but more attractive to its parasitoids. Application of such non-host plant compounds can be explored to develop push-pull systems to reduce oviposition by a pest insect and at the same time enhance parasitism by its parasitoids in crops.