思茅松毛虫3个地理种群性信息素成分差异分析

[目的]分析思茅松毛虫雌成虫不同地理种群间性信息素成分、含量和比例差异,比较雄成虫触角敏感性和不同配比诱芯诱捕效果差异,开发不同地域有针对性的思茅松毛虫种群监测方法和诱捕防控技术。[方法]运用气相色谱(GC)分析思茅松毛虫湖南、云南和江西地理种群雌虫性信息素腺体提取物,利用触角电位仪(EAG)测定思茅松毛虫各地理种群雄蛾触角对性信息素标准品及其不同配比组分的电生理敏感性,然后进行林间生物测定,比较不同配比的性信息素成分诱蛾效果。[结果]思茅松毛虫性信息素腺体中含有顺5,反7-十二碳二烯乙酸酯(Z5,E7-12:OAc)、顺5,反7-十二碳二烯醇(Z5,E7-12:OH)和顺5-十二碳烯乙酸酯(Z5-12:OAc)3种成分,3个地理种群间这3种腺体成分含量和比例存在微小差异。3种成分以100:10:25或者100:10:10的比例配比,不同地理种群间均具有很好的触角电位活性和林间诱蛾活性。[结论]思茅松毛虫性信息素组分还没有发生明显的种下分化现象,3个地理种群间性信息素含量和比例的细微差异暗示着与地域差异、寄主植物差异和人为化学防控干扰等因素相关。     

金钱松小卷蛾性信息素的研究

本文对金钱松小卷蛾（ＣｅｌｙｐｈａｐｓｅｕｄｏｌａｘｉｃｏｌａＬｉｕ）雌性信息素进行了研究。室内观察的结果表明，在光周期为１４：１０的条件下，雌蛾求偶在黑暗４ｈ时达到高峰，求偶百分率达到８５％。对雌蛾性信息素腺体的正己洗抽提液用高效毛细管色谱仪进行分析，获得了五个信息素组分。利用乙酰化反应，色谱分析，标样对照以及色－质联用证实，鉴定出这五个化合物分别是１２：ＯＨ、Ｚ１０－１２：ＯＨ、１２：Ａｃ、Ｚ９－１２：Ａｃ和Ｚ１０－１２：Ａｃ。它们的比例是：６．８：５．４：２４．５６：１：２２．２９。在风洞中用雌蛾性信息素腺体抽提物、合成性信息素组分作为诱芯，均能引诱雄蛾产生从起飞、定向、到降落在信息素源这一系列性行为反应。林间生物试验亦证实了这一结果。     

灰斑古毒蛾性信息素研究

通过观察和研究表明,灰斑古毒蛾的处女雌蛾对林间雄蛾有较强的引诱作用,而雄蛾对林间的雌蛾没有引诱作用。林间的雄蛾对处女雌蛾的昼夜反应节律发生在全天,每天有两个反应高峰,强峰为8:00—9:00,弱峰为22:00—23:00。其他时段虽有趋性反应,但反应强度比较弱,认为雄蛾对处女雌蛾的昼夜节律为"双峰式-全天型"。顺6-二十一碳烯-11-酮对灰斑古毒蛾具有一定的引诱作用,可能是其性信息素组分之一,而且,在所有的供试剂量中,1 000μg的顺6-二十一碳烯-11-酮诱捕效果最好,为该虫的最佳剂量。利用信息素诱捕器对灰斑古毒蛾成虫发生期监测表明,第2代成虫扬飞的开始时间为9月13日,扬飞高峰期为9月17日,扬飞末期为10月22日,成虫扬飞的持续期为40天。     

皮暗斑螟性信息素研究

通过室内人工饲养与枣树林间定时定点观测相结合的方法,对皮暗斑螟的生殖生物学进行观测.傍晚(17-20时)羽化的成虫占总量的45.71%,交尾多于午夜后至凌晨前进行.在室内通过气相色谱与触角电位测定相结合的方法,测定皮暗斑螟雄蛾对来自雌蛾性腺的不同化合物的反应,通过应用全二维气相色谱飞行时间质谱分析技术,初步明确了皮暗斑螟性信息素组分为(Z9,E12)-十四碳-9,12-二烯-1-醇[(Z,E)-9,12-14:OH]和(Z9)-十四碳-9-烯-1醇(Z9-14:OH).对二组分及其同分异构体的单体和混合物进行了林间引诱试验,初步结果表明(Z,E)-9,12-14:OH的诱虫效果较好.5,50,500和1 000 μg不同剂量诱芯的田间引诱试验证明,500 μg剂量诱芯诱虫量最多.     

小木蠹蛾雄蛾对雌蛾性信息素提取物及合成标准化合物的电生理反应

小木蠹蛾 (ＨｏｌｃｏｃｅｒｕｓｉｎｓｕｌａｒｉｓＳｔａｕｄｉｎｇｅｒ)是北京、天津等地园林树木白蜡、国槐、丁香、银杏、海棠等主要蛀干害虫 ,据 1 979年对北京市行道树的调查 (高瑞桐等 ,1 983;蒋三登等 ,1 983) ,遭此虫危害严重的地方被害株率高达 80 %以上。 1 998年再次调查发现 ,虫害程度有增无减 ,在一根长 50ｃｍ、直径8ｃｍ白蜡树段内幼虫达 2 63头。受害树株常发生风折、枯枝甚至整株死亡。同时幼虫从树干内排出粪屑挂满树枝树干或飘落地上 ,有碍市容卫生。防治方法主要是修除被害树干和施用化学药剂 ,长期使用这些方法不仅…     

Studies on trapping of Fall Webworm moth,Hyphantria cunea (Drury) (Lepid., Arctiidae)

With the aim of optimizing the trapping ofHyphantria cunea (Drury) males through pheromones, the activity of various traps, doses of pheromone components and dispensers was investigated. The best degree of activity was obtained by funnel traps (Uni-traps) with high capture ability and satisfactory representation of the flight curve when the population of the moth is high. On the contrary, the sticky traps gave good results in low density population. Comparing the activity ofH. cunea to the pheromones, (3Z, 6Z, 9S 10R)-cis-9,10-epoxy-1,3,6-heneicosatriene (or TEP), (3Z, 6Z, 9S 10R)-cis-9,10-epoxy-3,6-heneicosatriene (or DEP) and linolenic aldehyde (or TAL), the results obtained showed different responses according to the areas considered. Blend 1∶1∶1 of DEP:TAL:TEP revealed better results in the Venezia area (north-east Italy), while the activity of the Japanese dispenser (2∶30∶1) was highest in the Novara area (north-west Italy); on the contrary no significant differences were noted in Bergamo, the middle area considered. These results denote that the Italian population ofH. cunea could be made up of different strains, introduced from different geographical areas, with the presence of pheromone dialects.     

Zur Überwachung des grünen Eichenwicklers,Tortrix viridana L. (Lep., Tortricidae) mittels synthetischen Sexualpheromons

In the period from 1986 to 1988 the synthetic sexual pheromone ofTortrix viridana L. and different types of traps were investigated in Slovakian oak forests. The dependence of male numbers per trap on the forest type groups was studied parallely as well as the attraction of pheromones for other moth species was tested, too. The pheromon TV83 (Z11-14: Ac+Z11-14: OH, 9∶1, 50 μg) and unsticky plastic trap with DDVP called “Mushroom” showed the highest effectivity. The pheromon monitoring confirmed the theory that the pest prefers the biotops with dominance ofQuercus pubescens andQ. robur. The optimum of pest was bound to forest type groups Carpineto-Quercetum und Ulmeto-Fraxinetum carpineum. The minimal number of other moth species was observed in traps with pheromons TV83 (?SFR) and Hoechst (FRG).     

Reflections on structure and function of pheromone glands in storage insect species

Several polyphagous coleopteran and lepidopterous species, presently known as storage insects, have presumably evolved from free-living ancestral species, being capable of growth and reproduction on stored, desiccated and often nutritionally deficient foodstuffs. These potentially harmful insect species have probably adapted themselves to the newly acquired storage biotope by means of a well-developed sensory equipment serving food acquisition, aggregation and mate finding.Information by molecules may be communicated among the individuals of an insect species by means of relatively volatile pheromones (Greek, pher=convey) being emitted by exocrine glands and mainly carried by moving air to the sensilla of responsive individuals, or among the internal organs of an insect by means of relativelynonvolatile hormones (Greek, horma=impel), secreted fromendocrine glands and transported by the haemolymph to the receptors of target organs. It was postulated that pheromones were among the first chemical messengers utilized during evolution of animal behaviour, and that the pheromones of primitive protozoans could have been precursors of the hormones of metazoans. Hormones of the neurosecretory cells and corpora allata were found to induce sex pheromone biosynthesis in femaleTenebrio molitor, while dietary intake of a juvenile hormone analogue was shown to significantly enhance the production of aggregation pheromones in the males of certain silvanid and cucujid species.Aggregation pheromones are usually produced by the longlived and feeding males of several coleopteran species (Table 2) which deposit those chemical messengers to the substrate, where they induce the formation of bisexual assemblies supporting feeding, mating and reproduction. Sex pheromones are mostly produced by the short-lived and non-feeding females of several coleopteran and lepidopterous species (Table 2); females of those species usually release their sex pheromones to the air space during calling, and thus attract conspecific males for mating (Fig. 5 a–c).In some dermestid species, pheromone emission differs from the above scheme. Females of the short-lived and non-feedingTrogoderma granarium andT. inclusum release a phromone acting as a sex attractant for conspecific males and—in synergistic combination with tactile stimuli—as an assembling scent for conspecific females (Figs. 1 a, b, 2 and Table 1), females of the short-lived and feedingAntbrenus verbasci, Attagenus megatoma andAtt. elongatulus produce a sex pheromone for conspecific males, while females of the long-lived and feedingAn. scrophulariae emit a sex pheromone which lures conspecific males.Males of the long-lived and non-feeding bruchid speciesAcanthoscelides obtectus release a sex pheromone which attracts conspecific females. Androconial pheromones are discharged during courtship from the alar scales and abdominal tufts found in males of several microlepidopteran species (Phycitidae) includingAnagasta kuebniella, Cadra cautella, Ephestia elutella andPlodia interpunctella (Fig. 6 b–c); those aphrodisiac pheromones are known to enhance the specific responsiveness of the females to their mates. Electrophysiological recordings revealed that aggregation pheromones elicit considerable receptor potentials in the antennal olfactory sensilla of both sexes, whereas sex pheromones induce high receptor potentials in the antennal olfactory sensilla of one sex only. It was assumed that aggregation pheromones may be the evolutionary precursors of sex pheromones.Pheromone-producingexocrine glands are essentially groups of modified epidermals cells which are found in different body regions of male and/or female storage insect species. A simple pheromone gland, consisting of a single layer of adjacent secretory cells beneath the endocuticle of the 5th visible abdominal sternite, occurs in femaleTrogoderma granarium (Fig. 3 a). A more complex design, comprising an intra-abdominal semiglobular pheromone gland with numerous secretory cells being connected to tubuli which lead to an invaginated cuticular cribellum, is available in maleDermestes maculatus (Figs. 3 c, d and 4 c). The cribellum, provided with a caudally curved brush of fluted brisles, occurs in the centre of the 4th visible abdominal sternite (Figs. 4 a, b and 7 b). An apodemous exocrine gland is found in the lumen of the second abdominal segment of femaleLasioderma serricorne (Fig. 3 b). This lobate gland comprises many secretory cells, being connected by numerous tubuli to a sheath-like conical duct enveloping a V-shaped skeletal apodeme, which terminates in the abdominal tip. In maleTribolium castaneum, the secretory cells of both pheromone glands are connected by tubuli to two cribella, being densely covered by fluted bristles, and found in the femora of both forelegs (Fig. 7 a). Females of the phycitid speciesAnagasta kuebniella, Cadra cautella, Ephestia elutella andPlodia interpunctella are equipped with an intersegmental pheromone gland, situated between the 8th and 9th abdominal segment near the genital opening. The exocrine gland of the four moth species consists of a single layer of columnar secretory cells, lined by a spongy cuticle which seems to be permeable to the sex pheromone (Fig. 6 a). The latter is disseminated by calling females (Fig. 5 a, b) while their exocrine glands are widely exposed. Males of the above phycitid species are furnished with alar and abdominal androconia which become exposed during courtship and discharge aphrodisiac pheromones. The base of each of the androconial bristles and scales is immersed to an underlying unicellular, pheromone-producing gland (Fig. 6 d, e). The aphrodisiac pheromones, being secreted by the above glandular cells, are passing the lumen and walls of the bristles and scales, and evaporate from the surface of the latter. For example, malePlodia interpunctella possess 2 pairs of scent tufts (a small and a large one) on both sides of the 8th abdominal tergiet as well as 2 pairs of scent tufts (a small and a large one) near the base of the costal margin of the forewings (Fig. 6 b, c). Females of several phycitid species respond to the aphrodisiac pheromone of conspecific males by a pronounced readiness to mate.In the course of time, about 3 dozens of insect species (3/4 coleopteran and 1/4 lepidopterous species) have undergone sympatric speciation by sharing desiccated food in stores as a common habitat. Fertile matings between such heterogeneous species are often prevented by morphological and anatomical incompatibilities as well as physiological and behavioural barriers. Most of the species living in the storage habitat are reproductively isolated due to the molecular structure and blend composition of their pheromones (Table 2). Interestingly, some species (listed below) deviate from the majority by sharing the structure of their main pheromone components (mentioned in parenthesis), and are thus poorly separated: the curculionidsSitophilus oryzae andS. zeamais ((4S,5R)-5-hydroxy-4-methyl-3-heptanone), the tenebrionidsTribolium castaneum andT. confusum ((4R,8R)-dimethyldecanal) as well as the dermestidsTrogoderma inclusum andT. variabile ((R,Z)-14-methyl-8-hexadecenal). Theinsufficient reproductive isolation of the above species is compensated, i.a., by additional availability of a sex pheromone in femaleTribolium confusum, by different calling periods and emission rates of (R,Z)-14-methyl-8-hexadecenal in females of the forementionedTrogodema species.Trogoderma glabrum andT. granarium areincompletely isolated by sharing (R,E)-14-methyl-8-hexadecenal as a pheromone component; they are indeed capable of cross-mating, but produce sterile hybrids. Moreover, maleOryzaepbilus mercator andO. surinamensis incorporate (Z,Z)-3,6-dodecadien-11R-olide as a common chiral component to their aggregation pheromones. The females of 5 phycitid species share (Z,E)-9,12-tetradecadien-1-yl acetate as their main pheromone component, while they are reproductively separated by additional emission of (Z)-9-tetradecen-1-yl acetate and (Z,E)-9,12-tetradecadien-1-ol as secondary pheromone components, by the production of different androconial pheromones in conspecific males as well as different circadian calling activities.In the course of their research engagement on pheromones of storage insect and mite species (during the past 2.5 decades), the authors enjoyed fruitful collaboration with several renowned investigators working in Athens, Berlin, Hamburg, New York, Pantnagar, Tiantsin, Tokyo, Wisconsin, Yokohama and Zürich (chapter 6).Motto ...In addition to the amazing range of physiological activities of which it is capable during the process of moulting and cuticle formation, the epidermal cell is potentially an embryonic cell, with latent powers of differentiating in several different directions. The ordinary epidermal cell may divide to give rise to a pair of oenocytes. It may divide into four and produce a dermal gland cell with associated cells that form the glandular duct. Or the four daughter cells may differentiate into the bristle-forming and socket-forming cells which give rise to the sensillum and into the sense cell with its neurilemma cell both of which grow inwards to become a part of the central nervous system ...V B. Wigglesworth, 1959With 2 tables and 7 figuresDedicated to the memory of Prof. Dr. Sir Vincent BrianWigglesworth who died on February 12th, 1994.     

榆木蠹蛾性诱剂的合成及林间诱蛾试验

利用毛细管气相色谱分析榆木蠹蛾处女雌蛾性腺体提取物、化学合成相应的标准化合物并通过触角电位分析及林间诱蛾试验,旨在找到一种对榆木蠹蛾成虫具有强引诱活性的性诱剂.结果表明:提取物中存在反-3-十四碳烯醇(E3 - 14∶OH)、顺-3-十四碳烯醇(Z3 - 14∶ OH)、反-3 -十四碳烯醇乙酸酯(E3 - 14∶Ac)、顺-7-十四碳烯醇乙酸酯(Z7-14∶ Ac)和顺-3-反-5-十四碳烯醇乙酸酯(Z3E5 -14∶ Ac).榆木蠹蛾雄蛾对Z7-14∶ Ac产生最强的触角电位(EAG)反应,为4.95 mV,极显著高于其他化合物,其他依次是E3 - 14∶Ac、Z3E5 -14∶Ac、E3E5 -14∶ Ac、Z3 - 14∶Ac、腺体提取物、E7 - 14∶Ac,其中乙酸酯化合物EAG值极显著高于其相应的醇(P＜0.01).林间诱蛾活性试验表明:Z7- 14∶ Ac有诱蛾活性,E3 - 14∶Ac和Z3E5 - 14∶ Ac有显著的增效作用,Z7-14∶ Ac、E3 - 14∶Ac和Z3E5 - 14∶ Ac按10∶ 4∶4的比例配成每个含900 μg性诱剂的诱芯具有很好的诱蛾活性,单诱芯日平均诱蛾数达11.02头.     

云杉球果小卷蛾性外激素的诱捕试验

1992～1993年在牡丹江柴河林业局红皮云杉母树林和大兴安岭红皮云杉天然林对为害云杉球果的云杉球果小卷蛾Cydiastrobilella进行了性外激素诱捕试验。该性外激素于1991年实验合成，共有8种成份组合不同的诱芯，诱捕结果表明第6号诱芯［(100μgZ8-12OH+100μgE8-12OH+100μgZ8E10-12OH)×60］效果最好。同时也用该性外激素对为害兴安落叶松球果的东北小卷蛾C．illutanadahuricolana进行了诱捕尝试。     

沙柳木蠹蛾性诱剂的化学合成与林间生物活性评价

采用气相色谱仪分析,发现沙柳木蠹蛾雌虫性信息素腺体中存在顺-7-十四碳烯醇(Z7-14:OH)、顺-5-十四碳烯醇乙酸酯(Z5-14:Ac)、顺-7-十四碳烯醇乙酸酯(Z7-14:Ac)和顺-9-十六碳烯醇乙酸酯(Z9-16:Ac)4种成分。通过化学合成获得相应的化合物,对这些标准品进行室内触角电位测定和林间生物测定,评价其对沙柳木蠹蛾的生物活性。结果表明:Z7-14:Ac和Z5-14:Ac按一定比例复配后有明显的引诱活性,在此二者的复配物中加入少量Z7-14:OH,诱蛾量稍有增加;将Z7-14:Ac,Z5-14:Ac和Z7-14:OH以10∶8∶1的比例配制成总含量为760μg的诱芯,与三角形诱捕器结合可用于对沙柳木蠹蛾进行诱杀。     

合成性信息素对枣镰翅小卷蛾雄蛾田间诱捕试验

１９８１～１９８４年中国科学院上海有机化学研究所和山西农业大学激素研究室合作,对枣镰翅小卷蛾（ＡｎｃｙｌｉｓｓａｔｉｖａＬｉｕ）性信息素的成分、结构进行了测定,证明其成分为Ｅ９１２∶Ａｃ和Ｚ９１２∶Ａｃ,二者以Ｅ／Ｚ为８∶２比例在田间的诱蛾效果...     

Synthetische Sexual-Pheromone und deren Inhibitoren für Choristoneura murinana Hbn. (Tannentriebwickler. Lepidoptera: Tortricidae)

In a specific field-screening test it could be shown that (Z)-11-tetradecenylacetate is an attractant for males ofCh. murinana. (Z)-11-tetradecenylacetate in combination with (Z)-11-tetradecenol, (Z)-11-tetradecenal or (E)-11-tetradecenal showed synergistic effects. (E)-11-tetradecenylacetate (and to some extent (E)-11-tetradecenylacetate. (Z)-11-tetradecenylacetate alone or in combination with its synergists could be used in integrated pest management programmes of European forests.

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Mit einer Abbildung und 3 Tabellen

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Hoechst Aktiengesellschaft.     

(+)-柠檬烯和1-甲氧基-2-丙醇对云杉八齿小蠹虫对信息素混合物反映的影响(英文)

对利用信息素诱捕云杉八齿小蠹的策略进行了对比分析,尤其是雄性小蠹的诱捕。第一种策略是障碍法,在林分的周围密集的布置捕捉陷阱,使用交互式信息素分别诱捕雄性小蠹和雌性小蠹。第二种策略是单一诱捕法,广阔使用投有相同诱饵诱捕陷阱,以捕捉最大数量的雄性小蠹为目的,而不包含雌性小蠹的捕捉。在带有低含量的(4S)一反式马鞭草烯醇诱饵混合物中,用0%,1%,10%,35%,60%and90%的(+)-柠檬烯逐步取代α-蒎烯。这种替换对雄性小蠹的反映数量没有影响,但对雄性小蠹的捕捉量稍有影响。在有高含量(4S)-反式马鞭草烯醇捕捉雌性小蠹的引诱剂混合物中,用1-甲氧基-2-丙醇取代2-甲基-3-丁烯-2-醇,对雌性小蠹的捕捉率没有影响。因而,在具有反式马鞭草烯醇和(4县)-2-甲基-6-甲基-2,7-辛-4-醇的混合物中使用1-甲氧基-2-丙醇,捕捉效果没有明显的变化。在单一捕捉的引诱剂混合物中,用(+)-柠檬烯取代α-蒎烯,用1-甲氧基-2-丙醇取代2-甲基-3-丁烯-2-醇,α-蒎烯被代替后对雄性小蠹的捕捉率轻微的影响,但2-甲基-3-丁烯-2-醇被代替后,将不会没有明显地降低捕捉效果。     

Control ofEphestia kuehniella Zell. by sex pheromones in the flour mills

The possibility of controlling ofEphestia kuebniella Zell. by mass-trapping, mating-disruption and attracticide method was investigated in Northern Italy from 1986 to 1992.Considerable progress has been made in these years in controlling of mediterranean flour moth with sex pheromone (Z9E12-14Ac or TDA). The utilization of synthetic pheromone could lead to a drastic reduction of chemical treatments with consequent economic and qualitative advantages, protecting goods from residual products noxious to consumers and improving the image of the firm.

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Zusammenfassung Es wurden von 1986 bis 1992 in norditalienischen Mühlen Versuche zur Bekämpfung vonEphestia kuehniella durch Massenfang, Kopulationsverhinderung und Anlockung/Vergiftung durchgeführt. Es ergaben sich beachtliche Erfolge mit dem Sexualpheromon Z9E12-14Ac (=TDA). Es konnte damit eine drastische Verminderung der chemischen Bekämpfung erreicht werden, woraus wirtschaftliche Vorteile und ein besseres Image bei den Verbrauchern resultierten.

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With 5 figures     

杨树分月扇舟蛾性信息素研究

分月扇舟蛾ＣｌｏｓｔｅｒａａｎａｓｔｏｍｏｓｉｓＬｉｎｎ．是危害杨树的重要害虫之一．为了做好防治该虫的基础工作，首先对雌蛾求偶特性及雄蛾风洞行为进行了观察，然后采用毛细管气相色谱及ＧＣ－ＭＳ分析对雌蛾性信息素进行了研究．结果表明：在光周期Ｌ∶Ｄ＝１４∶１０的条件下，黑暗８ｈ的性信息素抽提物已具有引诱活性，雌蛾求偶在黑暗９ｈ达高峰，求偶率高达９０％；雄蛾风洞行为反应以２日龄的反应较强；比较黑暗６～９ｈ雌蛾性信息素腺体的正已烷抽提液的气相色谱图，从色谱峰的消长并综合考虑风洞试验及求偶规律，确定了活性峰；微量化学反应及ＧＣ－ＭＳ分析结果表明，分月扇舟蛾性信息素活性组分为含有两个双键的Ｃ１４醛．     

Monitoring and efficacy of selected insecticides for European corn borer (<Emphasis Type="Italic">Ostrinia nubilalis</Emphasis> Hubn., Lepidoptera: Crambidae) control

The European corn borer (ECB), Ostrinia nubilalis (H?bner) (Lepidoptera: Crambidae), is the major arthropod pest of corn in Croatia. However, chemical control is carried out only in maize for seed production, and in sweet corn. A 3-year investigation was carried out in corn fields in northwest Croatia to establish the most attractive pheromone lure for ECB monitoring, the optimal timing of insecticide applications, and the efficacy of selected insecticides against ECB. During each of the 3 years, the pheromone lures E, Z and E/Z («Isagro») were evaluated in the field from May to July. Insecticides were sprayed 14–20 days after the maximal capture in 2002 and 2003. In 2004, three different trials were set up: one trial with one early treatment (when corn was in the R49 development stage according to the extended BBCH scale); one with one late treatment (when corn was in the R65 development stage according to the BBCH scale); and one with two treatments in both stages. In the trials studying Bacillus thuringiensis var. kurstaki (B.t.k.), insect growth regulators (IGR), spinosad and classical chemical insecticides were applied. Pheromone lure E was the most attractive for monitoring ECB flights throughout 2 years of investigation. Insecticide efficacy depended on application timing. The insecticides most suitable for integrated pest management (IPM) programs, including spinosad, B.t.k. and IGR, resulted in high (spinosad) to moderate (B.t.k.) efficacy. The efficacy of IGRs indicates the need for earlier application. The efficacy of chemical insecticides depended on the year and the insecticide. The organophosphate (OP) insecticides and pyrethroids gave moderate to good results; imidacloprid did not provide significant efficacy. One application of all insecticides based on proper (early) timing resulted in the same efficacy as two applications of the same insecticides.     

The effects of 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one on two species of <Emphasis Type="Italic">Spodoptera</Emphasis> and the growth of <Emphasis Type="Italic">Setosphaeria turcica</Emphasis> in vitro

Maize seedlings contain high amounts of glucosidically bound 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA). The effects of DIMBOA on the feeding behaviour and performance of two noctuids, Spodoptera exigua Hübner and S. frugiperda Smith, were compared. The question was raised whether S. frugiperda, preferring maize and other Poaceae, is better adapted to DIMBOA than S. exigua. In addition, the effects of DIMBOA on the mycelial growth of the plant pathogen Setosphaeria turcica Leonard et Suggs (causal agent of northern corn leaf blight) was assessed in vitro. DIMBOA had an antifeedant effect on S. exigua but stimulated feeding in S. frugiperda in dual-choice experiments. In a no-choice setup, larvae of S. exigua gained less biomass and had a prolonged development when feeding on an artificial diet containing DIMBOA. However, pupal weight was not significantly different between treatments. In contrast, larvae of S. frugiperda were not affected by DIMBOA. Strong detrimental effects of DIMBOA were found on the mycelial growth of the pathogen S. turcica.     

First evidence of deuterotokous parthenogenesis in the tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)

The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), originates from South America and is now considered to be one of the most damaging invasive pests of tomatoes in the Mediterranean Basin countries of Europe and North Africa. The preventing pest mating control methods include: (1) the use of synthetic pheromones for male attraction and annihilation inside insecticide-containing traps; (2) mating disruption by saturating the atmosphere with sex pheromones which alter the ability of males to locate females; and (3) massive applications of sterile males to alter the overall reproductive success of the pest population. However, all these methods achieve only a poor success rate in controlling T. absoluta populations under greenhouse conditions. Sex pheromone management and sterile insect techniques are both based on an important biological trait: the insect must breed through sexual reproduction. Here, we report for the first time laboratory evidence of deuterotokous parthenogenesis, an asexual reproduction where both males and females are produced from unfertilized eggs. We discuss the consequences for T. absoluta control strategies.     

Effect of (+)-limonene and 1-methoxy-2-propanol on Ips typographus response to pheromone blends

We compared two different strategies to increase the catches of Ips typographus (L.), particularly males, in pheromone-baited traps. The first of these strategies, the barrier approach, used alternating pheromone blends, targeting males and females respectively, in closely-spaced traps forming a barrier around forest stands. The second strategy, the single trap approach, used widely-spaced traps that were all baited with the same lure and intended to trap the highest possible numbers of males without compromising trapping of females. In the blend used for the barrier traps targeting primarily males, with a lower percentage of (4S)-cis-verbenol (cV), the (−)-α-pinene was replaced step wise with (+)-limonene at rates of 0%, 1%, 10%, 35%, 60% and 90%. This replacement had no significant effect on the numbers of responding I. typographus males, but there was a slight effect on the percentage of males caught. In the attractant blend for the barrier traps targeting females, with a higher percentage of cV, the 2-methyl-3-buten-2-ol (MB) was replaced with 1-methoxy-2-propanol (MP) in a similar fashion as for the male-specific blends. The replacement did not significantly affect the catch of females. Thus, it is possible to use the MP in the blend with cV and ipsdienol without significant change in catch efficacy. In the blends for single traps, the (−)-α- pinene was replaced with (+)-limonene and MB with MP. The replacement of (−)-α-pinene had only a slight effect on the percentage of males, but the results suggest that replacing MB with MP in the blend will not significantly reduce trapping efficacy. Foundation project: The research was supported by Slovak Research and Development Agency (APVV-51-P06005 and APVV-27-P05205) and by the Scientific Grant Agency of the Ministry of Education of the Slovak Republic and the Slovak Academy of Sciences (2/6153/26)