非嗜食植物次生物质对小菜蛾产卵驱避和拒食作用的研究

基于植物与昆虫的协同进化理论,利用25科37种小菜蛾非嗜食植物的茎、叶、花或根的乙醇提取物,研究其对小菜蛾成虫的产卵驱避作用和对幼虫的拒食作用。结果表明,供试植物提取物对小菜蛾有不同程度的产卵驱避和拒食效果,羊蹄甲、细叶桉、飞扬草、假连翘、花椒、荷花玉兰、烟草的乙醇提取物对小菜蛾成虫产卵有较好的驱避效果,驱避率均达80％以上,一品红、构树、艾蒿、茶枯、垂柳、飞扬草、羊蹄甲、狗尾草的乙醇提取物对小菜蛾幼虫有较好的拒食作用,48h的拒食率达80％以上。     

印楝素的杀虫活性及其对烟粉虱的驱避作用

印楝素(azadirachtin)被认为是最有发展前景的植物源杀虫剂。文章主要介绍印楝素对昆虫的接触驱避、产卵驱避、拒食、毒杀、降低生殖力、生长调节等作用及其作用机理。同时也论述印楝素对烟粉虱Bemisia tabaci(Gennadius)寄主选择、产卵、孵化、若虫发育的影响。     

烟碱对假眼小绿叶蝉和茶尺蠖的忌避(拒食)活性

【目的】尼古丁是茄科植物的重要生物碱,本文首次确定了硫酸烟碱对假眼小绿叶蝉Empoasca vitis G?the的驱避作用和田间防效,以及不同浓度硫酸烟碱对茶尺蠖Ectropis obliqua Prout的拒食作用。【方法】使用Y形嗅觉仪和T形观测室研究了假眼小绿叶蝉对硫酸烟碱的行为反应,使用叶碟法测试了硫酸烟碱对茶尺蠖的拒食作用。【结果】硫酸烟碱600倍稀释液和800倍稀释液处理茶梢分别对叶蝉若虫的寄主选择行为和雌成虫的产卵具有显著的驱避作用;田间喷施硫酸烟碱对假眼小绿叶蝉的防治效果较好。此外,硫酸烟碱对茶尺蠖幼虫具有拒食作用,并且拒食作用随着取食时间的延长而增强,取食8 d以后,死亡率显著高于对照。【结论】本研究结果为开发茶树害虫的植物源忌避(拒食)剂提供一定的科学参考。     

介绍二种记录昆虫取食行为的电子装置

<正> 昆虫拒食剂在害虫防治上的作用随植物杀虫剂及植物抗虫性的研究愈来愈受到广泛的重视。拒食作用的测定则是研究这一类杀虫剂的重要方面。国外目前用于研究昆虫取食行为和寄主适食性的二种电子装置对正确评价拒食剂效果以及区别忌避与拒食将会有很大帮助。本文对其一般原理及构造作一介绍,供大家研究参考。 一、刺吸式口器昆虫取食记录装置 McLean等(1964)最早设计了一种电子测定系统(electronic measurement system)记录蚜虫的取食行为。后来,许多研究者对其进行     

芳香植物与“推-拉策略”

正关于植物与昆虫之间的互作关系,尤其是植物挥发性成分作用的探究,一直都是国内外关注的热点。芳香植物是一类新兴的经济作物,常用于食品工业、日化工业、医药和生物防治等领域。目前关于芳香植物、精油及单体挥发性成分对昆虫生物活性的研究主要集中在熏蒸、触杀、拒食、生长发育抑制、吸引和驱避等方面。     

植物次生代谢物质对蓟马的行为调控作用及其在蓟马防控中的应用

蓟马是多种农作物和园艺作物上的重要害虫,通过直接取食和间接传播病毒给作物造成巨大的经济损失。植物次生代谢物质在植物-昆虫互作中起到重要的作用,通过植物次生代谢物质调控害虫行为从而达到控制害虫的目的是一种害虫绿色防控的重要措施。本文综述了对蓟马类害虫具有引诱、驱避、抑制产卵、拒食、熏蒸毒性和毒杀作用的植物、植物提取物、植物精油和化合物,并讨论了植物次生代谢物质在蓟马防控中的应用潜能。对蓟马具有引诱作用的主要包括27科54种植物的挥发物或精油、29种苯环类、17种吡啶类和13萜烯类化合物,可开发为诱集植物和引诱剂;具有驱避作用的主要包括16科40种植物的挥发物或精油、20种萜烯类和6种苯环类化合物,可开发为驱避植物和驱避剂;具有抑制产卵、拒食、熏蒸毒性和毒杀作用的主要有20科42种植物的提取物或精油、6种生物碱类、15种萜烯类和5种苯环类化合物,可开发为植物源农药和熏蒸剂。本文最后讨论了应用植物次生代谢物质防控蓟马存在的作用效果不稳定、田间应用技术缺乏、作用机制不明确等问题,并展望了未来的研究方向,对基于植物次生代谢物质的蓟马绿色防控具有重要意义。     

十九种植物精油对茶丽纹象甲成虫的驱避和拒食活性

为了寻找茶丽纹象甲Myllocerinus aurolineatus Voss无公害防治新途径,采用行为生测法测定了19种植物精油对茶丽纹象甲的驱避和拒食活性。结果表明:大蒜油allitridi、芸香(Cantleyt corniculata(Becc)Howard)油、丹参(Salvia miltiorrhiza Bunge.)、穿心莲(Andrographis paniculata(Burm.f.)Nees)、艾叶(Artemisia argyi Levl.et Vant.)、薰衣草(Lavender angustifolia Mill.)、何首乌(Fallopia multiflora(Thunb.)Harald.)、苦参(Sophora flavescens Alt.)、黄岑(Scutellaria baicalensis Georgi)、益母草(Leonurus heterophyllus Sweet)和金银花(Lonicera Japonica Thunb.)提取物对象甲的雄性和(或)雌性具有驱避活性。其中,大蒜油、丹参、何首乌和苦参又分别对象甲的雌性或雄性具有显著的选择性拒食活性;与对照相比,芸香油和金银花提取物对象甲具有非选择性拒食活性,而大蒜油和益母草提取物会显著提高象甲的取食量。艾叶、薰衣草和黄岑提取物对象甲仅表现出一定的驱避活性,未表现出拒食活性。与对照相比,穿心莲提取物对象甲具有显著的引诱作用。本研究证明芸香油、丹参、何首乌、苦参和金银花5种物质对象甲具有多方面的作用活性,具有很好的研究价值和实践意义。     

薇甘菊对桔小实蝇的驱避试验初报

为了探索一种低毒、低残留的环保型驱避剂,分别在广州市番禺区杨桃园和广东省昆虫研究所大院内,以薇甘菊Mikania micrantha H.B.K对桔小实蝇Bactrocera dorsalis(Hendel)成虫进行驱避试验.结果表明,薇甘菊对桔小实蝇具有明显的驱避效果,在薇甘菊环境内诱杀桔小实蝇虫数明显低于正常环境诱杀虫数,全年1～12月薇甘菊环境内对桔小实蝇的驱避率为13.33～92.78%,全年平均驱避率为50.65%;杨桃园内,以薇甘菊甲醇提取物喷施的杨桃,可以把本地种杨桃的桔小实蝇为害率控制在50%以下,而对照的为害率超过80%.     

非嗜食植物中的昆虫产卵驱避物及其利用

产卵是植物性昆虫生命周期中的一个重要环节,它能反映昆虫与植物相互作用的某些特点以及植食性昆虫对植物利用的策略.植物中的驱避物质在调节昆虫产卵行为过程中起着十分重要的作用.大量研究结果表明:许多非嗜食植物含有对昆虫产卵有驱避作用的次生化合物.研究植物中的昆虫产卵驱避物质不仅能在理论上加深对植食性昆虫产卵机制,植食性昆虫与植物间的相互关系以及昆虫群落构建机制等的认识,同时在害虫综合治理中有广泛的应用前景.     

植物乙醇提取物对三化螟控制作用研究

研究了30种植物乙醇提取物对三化螟Scirpophaga incertulas(Walker)的产卵驱避效果,并用产卵驱避率及干扰作用控制指数(IIPC)对这些效果进行评价.结果表明,处理后48 h,10种植物乙醇提取物对三化螟产卵有显著的驱避作用,其中海芋Alocasia macrorrhiza产卵驱避率最高,达到82.79%,蜜柚Citrus grandis、三叶鬼针草Bidenspilosa、马蔸铃Aristolo chiachampionii、白蝴蝶Syngonium podophyllum 4种植物的产卵驱避率为75%以上,llPC低于0.13.非选择性的试验结果同样表明海芋和屿蔸铃的乙醇提取物对三化螟具有明显的产卵驱避作用.测定结果还表明,海芋乙醇提取物处理后三化螟初孵幼虫的钻人时间是对照的2.60倍,马蔸铃是对照的1.07倍;海芋乙醇提取物处理后三化螟的钻蛀率为40%,马蔸铃乙醇提取物则为58%,两者都明显低于对照钻蛀率98.33%.此外,海芋乙醇提取物对二化螟幼虫存活率的影响不明显,但是马蔸铃乙醇提取物对幼虫存活率的影响与对照相比差异显著.     

Insecticidal and antifeedant activities of proteins secreted by entomopathogenic fungi against Spodoptera littoralis (Lep., Noctuidae)

Abstract:  Entomopathogenic fungi are a poorly exploited source of insecticidal proteins, which may be used for the development of new natural insecticides and as alternative molecules for transgenic deployment. The crude soluble protein extracts in Adamek's liquid medium of 25 fungal isolates belonging to the fungal species Metarhizum anisopliae , Beauveria bassiana , Beauveria brongniartii and Scopulariopsis brevicaulis were screened by per os toxicity on Spodoptera littoralis larvae. Whilst extracts from two M. anisopliae and two B. bassiana isolates gave significant mortalities when applied either on alfalfa leaf discs or incorporated into artificial diet, the one from M. anisopliae 01/58-Su isolate was the only most toxic that showed promise for S. littoralis control. In leaf disc assays, this extract exhibited strong dose-related toxic and antifeedant activity against the larvae. At 10, 20 and 40  μ g protein/insect, the extract gave 61.3%, 96.6% and 100.0% mortality, respectively, and average survival time of 5.7, 4.3 and 3.1 days respectively. Not only the antifeeding index was dose-related, but it significantly increased over time in a dose-related manner. Longer exposure times led to a dose-related significant increase in larval mortality. The exposure times for 50% mortality were 91.3 h and 62.1 h for 20 and 40  μ g protein/insect respectively. The crude extract when exposed to higher temperature or protease treatment lost toxicity, indicating that toxicity was protein mediated. In addition, the liquid medium composition did not influence its insecticidal activity. The effects of the protein extract on midgut cells of second instar larvae of S. littoralis were investigated by using both light and electron microscopy. A progressive bleeding of the midgut epithelium into the gut lumen was observed along with lysis of the epithelium and deterioration of the microvilli.     

Isolation of Bacillus strains from the rhizosphere of cereals and in vitro screening for antagonism against phytopathogenic, food-borne pathogenic and spoilage micro-organisms

Bacillus strains were isolated from the rhizosphere of cereals in order to be used as natural biocontrol agents (BCAs). They were screened for antagonism in vitro against various test micro-organisms. The isolates showing antagonism were identified to species level. A combination of techniques was employed for the isolation of Bacillus species. Using the direct method, only one of the 25 isolates screened showed antagonistic properties. This strain (IFS-01) was identified by means of API test strips and the ATB Plus computer programme. It proved to be Bacillus subtilis and consequently has been designated as Bacillus subtilis IFS-01. This strain produced either a broad spectrum antimicrobial compound or several compounds with different activities. The fungi and Gram-positive bacteria were more sensitive to the antagonistic isolate than the Gram-negative bacteria. A Bacillus strain producing BCAs which can be used as biopesticides or organic preservatives has been isolated and identified.     

Rice straw-decomposing fungi and their cellulolytic and xylanolytic enzymes

Filamentous fungi colonizing rice straw were collected from 11 different sites in Korea and were identified based on characterization of their morphology and molecular properties. The fungi were divided into 25 species belonging to 16 genera, including 14 ascomycetes, one zygomycete, and one basidiomycete. Fungal cellulolytic and xylanolytic enzymes were assessed through a two-step process, wherein highly active cellulase- and/or hemicellulaseproducing fungi were selected in a first screening step followed by a second step to isolate the best enzymeproducer. Twenty-five fungal species were first screened for the production of total cellulase (TC), endo-beta-1,4 glucanase (EG), and endo-beta-1,4 xylanase (XYL) using solid-state fermentation with rice straw as substrate. From this screening, six species, namely, Aspergillus niger KUC5183, A. ochraceus KUC5204, A. versicolor KUC5201, Mucor circinelloides KUC6014, Trichoderma harzianum 1 KUC5182, and an unknown basidiomycete species, KUC8721, were selected. These six species were then incubated in liquid Mandels' media containing cellulose, glucose, rice straw, or xylan as the sole carbon source and the activities of six different enzymes were measured. Enzyme production was highly influenced by media conditions and in some cases significantly increased. Through this screening process, Trichoderma harzianum 1 KUC5182 was selected as the best enzyme producer. Rice straw and xylan were good carbon sources for the screening of cellulolytic and xylanolytic enzymes.     

A preliminary study of the occurrence of actidione-resistant fungi in sediments of Catalonian river mouths (Spain). I. Keratinolytic fungi and related Onygenales

Sediments from eight river mouths along the Catalonian coast (Spain) were surveyed for keratinolytic fungi and related Onygenales. The actidione plating technique was employed. Of 532 actidione-treated sediment samples, 268 (50.3%) were positive for the fungi. Altogether, 384 fungal strains from 35 species were isolated from the samples. Narasimhella marginospora, Aphanoascus fulvescens, Neoarachnotheca keratinophila with its anamorph Myriodontium keratinophilum, Narasimhella hyalinospora, Beauveria alba, Sporothrix schenckii, Chrysosporium lobatum and Gymnoascus littoralis were the predominant species in sediments. Abundance of N. marginospora was clearly correlated with the degree of water pollution with sewage. This revised version was published online in June 2006 with corrections to the Cover Date.     

海南文昌清澜港红树林真菌抗B16肿瘤细胞活性菌株的筛选

从海南文昌清澜港红树林采集78份植物组织和土壤样品。对样品进行真菌分离, 共分离得到真菌608株, 采用目测法对其体外抗肿瘤细胞活性进行检测, 发现81株红树林真菌对小鼠黑色素瘤B16细胞有不同程度的抑制作用, 占总分离菌株的13.32%。结果表明, 从红树植物杯萼海桑中分离得到真菌菌株的数量最多, 而从红树植物银叶树分离得到的抗肿瘤细胞活性菌株数量最多。     

海南文昌清澜港红树林真菌抗B16肿瘤细胞活性菌株的筛选

从海南文昌清澜港红树林采集78份植物组织和土壤样品。对样品进行真菌分离, 共分离得到真菌608株, 采用目测法对其体外抗肿瘤细胞活性进行检测, 发现81株红树林真菌对小鼠黑色素瘤B16细胞有不同程度的抑制作用, 占总分离菌株的13.32%。结果表明, 从红树植物杯萼海桑中分离得到真菌菌株的数量最多, 而从红树植物银叶树分离得到的抗肿瘤细胞活性菌株数量最多。     

Hydroxylations of Biphenyl by Fungi

Sixty-six species of fungi were screened for their ability to hydroxylate biphenyl. Thin-layer and gas chromatographic analyses indicated that seven organisms actively hydroxylated this substrate. Of particular interest were Cunninghamella echinulata ATCC 9244 which produced 4-hydroxybiphenyl as the major metabolite, Helicostylum piriforme QM 6945 which produced exclusively 2-hydroxybiphehyl, and Aspergillus parasiticus ATCC 15517 which produced a good yield of 4, 4'-dihydroxybiphenyl. These results were confirmed by isolation of the phenolic metabolites following preparative-scale conversions and comparisons of the isolated phenols with authentic reference materials.     

Interactions between Lotus japonicus genotypes and arbuscular mycorrhizal fungi

Abstract

Interactions between three genotypes (Ljsym 71-1, Ljsym 71-2 and Ljsym 72) of Lotus japoicus and one isolate from each of four species of arbuscular mycorrhizal fungi (Glomus sp. R-10, Glomus intraradices, Glomus etunicatum, and Gigaspora margarita) were investigated and compared with the wild-type ‘Gifu’ B-129. All the three genotypes showed no or defective internal colonization after inoculation with these AM fungi. In Ljsym72 mutant, the AM fungi produced deformed appressoria on the root surface, but failed to form any internal structures (internal hyphae, arbuscules and vesicles) except only in Glomus intraradices. The Ljsym71-1 and Ljsym71-2 mutants had more deformed appressoria and occasionally formed internal hyphae, arbuscules and vesicles, depending on AM fungi used. Wild-type ‘Gifu’ (nod⁺myc⁺) plants had typical colonization. The colonization of mutants by several fungi varied and provides a basis for studying recognition and compatibility between plants and mycorrhizal fungal species. These mutants also will be useful in studies of the genetics of the symbiosis between plant species and AM fungi.     

Bioactivities of seven chrysanthemum species flowers powder on Spodoptera littoralis (Boiduval) larvae

We have screened seven Chrysanthemum species, collected from different biotope in Tunisia for the antifeeding and growth regulatory activity against S. littoralis (Lepidoptera: Noctuidae) an insect pest of tomato. The flowers powder was added to the Poitout and Bues (1974) artificial diet at three concentrations: 4, 8, and 16%. After ten days of treatment, the consumed quantity determination revelled that these species have an antifeeding activity proportional to the concentration, more considerable for the C. fuscatum and C. Myconis flowers powder. At the concentration of 16% the larvae weight was significantly delayed in the average time to the control, these results were compared to the effect of Cestrum parquii on S. littoralis and Pieris brassicae The moulting date determination showed an elongation of the third, fourth and fifth stages at the high concentration probably due to the presence of juvenile hormones Analogues.     

Some characteristics of ammonia fungi 1. In relation to their ligninolytic enzyme activities

Twenty-six species of ammonia fungi comprising 71 strains were screened for ligninolytic activity using agar plate tests. The tests comprised a wood powder plate test, the Bavendamm reactions, and a Remazol Brilliant blue R (RBBR) decolorization test. The wood powder plate test detected phenol oxidases of Coprinus spp., whereas this method obviously detected no activities from facultative mycorrhizal fungi, such as Hebeloma radicosoides and ectomycorrhiza: H. spoliatum and H. vinosophyllum. With quantitative assays of ligninolytic activity, Coprinus phlyctidosporus, C. echinosporus, Lyophyllum tylicolor, Lepista nuda, L. tarda, Calocybe leucocephala, and Crucispora rhombisperma, which grow on oak-leaf litter, the major phenol-oxidizing enzyme was a laccase. The concentration of urea affected laccase activity; however, urea was not the obligate nitrogen source for the laccase production.