Bioassay evidence for a sex attractant pheromone in the large carpenter bee, Xylocopa varipuncta (Anthophoridae: Hymenoptera)

A field bioassay was conducted to test i˜hethercompoundsp roduced in the thoracic gland of male X. varipuncta are involved in long-range mate attraction. Filter paper impregnated with the two most abundant compounds of the male gland was placed in sites comparable to those used by territorial males during the time of day when mating activity occurs. Females visited these filter paper 'lures' as often as they visited unmanipulated males in the study area. Males with the chemical mixture added to their territories did not receive more matings than males at territories where we had not added the chemical mixture. These findings and other studies, summarized herein, support the hypothesis that the male gland produces a pheromone which functions as a long-range sex attractant.     

The sugarcane borer sex attractant

Investigations with the sugarcane borer sex pheromone have been conducted in the laboratory and field since 1964 to: (1) develop a suitable synthetic diet for rearing large numbers of larvae; (2) develop a reliable bioassay to aid chemical studies of the pheromone; (3) study male response in the field to the pheromone; (4) determine the effects on natural populations of trapping males in small field plots; and (5) identify the pheromone. More than 1,000,000D. saccharalis have been reared on synthetic diets during the past 4 years. Bioassay techniques for detecting active fractions separated during chemical studies have been developed. Statistically significant reductions in sugarcane borer infestations and damage to sugarcane have been attained in small replicated field plots. Male movement in the field has been studied utilizing marking and release techniques. About 1400 males of the bluegrass webworm,C. teterrellus, responded to cagedD. saccharalis females during two years of field work, thus providing evidence for a lack of species specificity of the pheromone.

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Résumé La découverte en 1964 d’une phéromone sexuelle efficace chez le foreur de la canne à sucre,Diatraea saccharalis (F.) a stimulé la recherche pour identifier et synthétiser la phéromone et faire l’étude de ses possibilités d’emploi dans la lutte contre ces ravageurs.D. saccharalis est le principal insecte nuisible à la canne à sucre en Louisiane où il cause environ 13% des pertes annuelles. Les femelles vierges commencent à émettre ce produit chimique après l’émergence et elles sont le plus attractives pendant les trois premiers jours de vie, ensuite l’attraction diminue avec l’age. Généralement les femelles cessent d’attirer les males après l’accouplement et la majorité des femelles s’accouplent seulement une fois dans la nature, où l’activité sexuelle a lieu entre une heure et quatre heures du matin. Plus d’un million de larves ont été élevées en laboratoire ces quatre dernières années. Environ 75% des abdomens des femelles obtenues ont été utilisés par les chimistes qui cherchent à identifier la phéromone. Des réductions significatives de l’infestation par le foreur et des préjudices à la canne à sucre ont été enregistrées dans de petites parcelles où étaient disposés 400 à 800 pièges par acre, chaque piège contenant une femelle vierge. Il n’y a pas eu de réductions significatives l’année suivante quand la densité des pièges a été réduite à 80 par acre, cependant les captures de males ont augmenté de presque 2,5 fois. Les nombres de males marqués recapturés au point de lacher ne diffèrent pas significativement si les lachers ont été faits à des distances de 40, 80, 160 et 320 pieds du piège renfermant les femelles vierges, et seulement 4,44 pour cent des males ont été recapturés. Ces phénomènes sont peut être dus à la dispersion des males à partir des points de lacher avant leur réponse à la phéromone. Le manque de spécificité de la phéromone a été déjà signalé. Pendant les deux ans d’essais dans la nature, les pièges avec les femelles vierges deD. saccharalis ont attiré beaucoup de males deCrambus teterrellus Zincken.

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Presented at the symposium OILB on borers of graminaceous plants. Paris, 24th sept. 1970.     

An aggregation attractant for the sugar-beet weevil, Bothynoderes punctiventris

During our screening studies, attractiveness of a ternary mixture of synthetic Grandlure I [racemic cis‐1‐methyl‐2‐(1‐methylenethenyl)‐cyclobutane ethanol], Grandlure II [(Z)‐2‐(3,3‐dimethyl)cyclohexylidene ethanol], and Grandlure III–IV [(Z)‐ and (E)‐2‐ochtodenal; (Z)‐ and (E)‐(3,3‐dimethyl)cyclohexylidene acetaldehyde] for the sugar‐beet weevil, Bothynoderes punctiventris Germar (Coleoptera: Curculionidae), was observed in field‐trapping tests at several sites in Hungary and Serbia. The mixture attracted both males and females. Later tests revealed that of the components in the ternary mixture, only Grandlure III–IV were responsible for attraction, and the addition of Grandlures I or II in varying percentages had no influence on trap captures. Traps baited with 50–50 000 µg of Grandlure III–IV on rubber or polyethylene dispensers yielded high catches of weevils. When testing synthetic samples enriched in the respective geometrical isomer, Grandlure IV had a tendency of catching more weevils, but differences were not significant from lower catches by a 1:1 Z:E blend or Grandlure III. In gas chromatography–flame ionization detection/electroantennographic detection studies, antennae of both female and male weevils were more responsive to the (E)‐ than to the (Z)‐isomer suggesting a more important role for Grandlure IV. Efforts to verify the presence of Grandlure III or IV in volatiles collected from either sex of live sugar‐beet weevils or body washings with pentane remained inconclusive. Traps baited with Grandlure III–IV can now be used as sensitive and powerful trapping tools in the control of the sugar‐beet weevil.     

Linyphid spider courtship: Releaser and attractant functions of a contact sex pheromone

Experiments with male bowl-and-doily spiders (Frontinella communis) on methanol-washed and unwashed female webs indicate that the courtship of males is chemically released. Parallel experiments on the webs of females of another linyphiid species and on immature F. communis webs indicate that the releaser pheromone is species specific and that it is produced only by mature females. The pheromone that releases male courtship also functions as an attractant, changing the male's orientation from negatively to positively geotactic. The presence or absence of a female on the test web has only a slight effect on the male's behaviour.     

性诱剂在沙棘木蠹蛾监测和控制中的应用

利用性诱剂在全国7个省9个地区对沙棘木蠹蛾Holcocerus hippophaecolus Hua,Chou,Fang etChen进行连续3年的野外监测和控制,结果表明：沙棘木蠹蛾性诱剂具有较好的野外监测和诱集效果,其中,平均诱蛾量最高的达26.6头/诱捕器,日诱蛾量最高的为45.9头/d,诱捕器之间的最佳设置距离为120 m,诱捕效率达50%以上。沙棘木蠹蛾性诱剂已成为沙棘木蠹蛾控制中最重要的措施之一,具有广阔的推广应用前景。     

Behavioral evidence for a female-produced sex attractant in Diaphorina citri

Diaphorina citri Kuwayama (Hemiptera: Psyllidae) is an important worldwide pest of citrus. It vectors three phloem-restricted bacteria in the genus Candidatus Liberibacter that cause huanglongbing (citrus greening disease). Studies were conducted to examine the behavioral responses of male and female D. citri to conspecifics of the same and opposite sex, with and without associated citrus host plants, in both open-air arena choice assays and Y-tube olfactometer assays. Virgin and mated male D. citri colonized citrus plants that were currently or had been previously colonized by virgin or mated female D. citri in greater numbers than control plants without females. However, males or females did not accumulate more on plants colonized by conspecifics of the same sex compared to uninfested plants, and females showed no preference for plants pre-infested with males compared with uninfested controls. In complementary Y-tube olfactometer assays, virgin and mated males chose arms with odor sources from mated females compared with blank controls in the absence of associated citrus host plant volatiles. In both behavioral assays, mated female D. citri appeared more attractive than virgin females. The vibrational calling behavior of male D. citri was reduced when males were challenged by the odors of conspecific mated females relative to when males were challenged by the odor of other males. Collectively, our results provide behavioral evidence for a female-produced volatile sex attractant pheromone in D. citri . Future identification and synthesis of a sex attractant pheromone will be an important contribution to current monitoring and management practices for D. citri .     

Bioassay of three sulphur containing compounds as rat attractant admixed in cereal-based bait against Rattus rattus Linn

Three sulphur containing compounds, carbon disulphide, dimethyl disulphide and dimethyl sulphide were bioassayed for preference after admixing them in cereal base as ready bait block for use against commensal rat, R. rattus (wild type) in four way choice chamber system. Rat preference for different baits was also studied with automatic recording animal activity meter. Rats exhibited attractancy to the baits at 0.005% concentration of all the three compounds while at 0.01% concentration they have showed repellency. Dimethyl sulphide at 0.005% concentration showed better attractancy towards both sexes of rat.     

A two-component sex attractant for males of the geometrid moth Alsophila quadripunctata

The binary mixture of the hydrocarbons (3Z,6Z,9Z)-3,6,9-nonadecatriene and (6Z,9Z)-6,9-nonadecadiene is a sex attractant for males of Alsophila quadripunctata Esp. (Lepidoptera, Geometridae). Triene/diene ratios from 1:1 to 1:0.01 attracted males in the field, the ratios 1:1 and 1:0.7 were most effective. The triene on its own also attracted males, but in significantly lower numbers than the 1:1 mixture. In a dosage test the highest dose, 1800 g of 1:0.8 [triene:diene] mixture applied to rubber caps was most effective. This is the first report of a geometrid sex attractant with field activity containing more than one component.

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Zusammenfassung Die binäre Mischung der Kohlenwasserstoffe (3Z,6Z,9Z)-3,6,9-Nonadecatrien [ZZZ3,6,9-19:H] und (6Z,9Z)-6,9-Nonadecadien [ZZ6,9-19:H] in den Verhältnissen 1:1 bis 1:0.01 erwies sich im Freiland als Sexuallockstoff für Männchen von Alsophila quadripunctata (Geometridae, Lepidoptera). Dabei besaß die 1:1-Mischung die beste Fängigkeit, das Nonadecatrien allein lockte schlechter, während das C₁₉-Alkadien unwirksam war. Ein Dosiswirksamkeitstest ergab bei Köderbeladungen von 1.8 mg (Trien:Dien + 1:0.8) die besten Fangergebnisse. Im Verlauf der Untersuchungen wurden weitere zwölf geometrische-oder positionsisomere C₁₉-Polyenkohlenwasserstoffe getestet, wobei keine der geprüften Verbindungen Attraktant-oder Inhibitorwirkung zeigte.

     

Effects of combining microbial and chemical insecticides on mortality of the Pecan Weevil (Coleoptera: Curculionidae)

The pecan weevil, Curculio caryae (Horn), is a key pest of pecan [Carya illinoinensis (Wangenh.) K. Koch]. Current control recommendations are based on chemical insecticide applications. Microbial control agents such as the entomopathogenic nematode, Steinernema carpocapsae (Weiser) and the fungus Beauveria bassiana (Balsamo) Vuillemin occur naturally in southeastern U.S. pecan orchards and have shown promise as alternative control agents for C. caryjae. Conceivably, the chemical and microbial agents occur simultaneously within pecan orchards or might be applied concurrently. The objective of this study was to determine the interactions between two chemical insecticides that are used in commercial C. caryae control (i.e., carbaryl and cypermethrin applied below field rates) and the microbial agents B. bassiana and S. carpocapsae. In laboratory experiments, pecan weevil larval or adult mortality was assessed after application of microbial or chemical treatments applied singly or in combination (microbial + chemical agent). The nature of interactions (antagonism, additivity, or synergy) in terms of weevil mortality was evaluated over 9 d (larvae) or 5 d (adults). Results for B. bassiana indicated synergistic activity with carbaryl and antagonism with cypermethrin in C. caryae larvae and adults. For S. carpocapsae, synergy was detected with both chemicals in C. caryae larvae, but only additive effects were detected in adult weevils. Our results indicate that the chemical-microbial combinations tested are compatible with the exception of B. bassiana and cypermethrin. In addition, combinations that exhibited synergistic interactions may provide enhanced C. caryae control in commercial field applications; thus, their potential merits further exploration.     

棉铃虫二种性诱芯田间诱蛾效果比较

棉铃虫Helicoverpa armigera(Hübner)是我国最严重害虫之一。为了提高监测和诱捕效率,2009年在山西和新疆进行2种性诱芯诱捕棉铃虫的田间试验,2种性诱芯分别来自中国科学院动物研究所和北京中捷四方公司,2种诱芯处理分别重复2次和6次,诱捕器分别为水盆和笼罩。试验结果:在山西试点,动物所诱芯的诱蛾数是中捷四方公司的8.60倍;在新疆试点,则达到11.89倍。以上差异均达极显著水准(P<0.01)。同时,在山西试点,动物所诱芯的有效期长达62d,比中捷四方公司的长14d。据此认为动物所棉铃虫性诱芯值得应用推广。     

落叶松球果花蝇头胸和腹部粗提液阻碍与引诱作用的试验

将雌性落叶松和黑松球果花蝇头胸和腹部充分研磨 ,加入溶剂正己烷得到粗提液。应用该粗提液进行了球果花蝇产卵阻碍信息素和性引诱信息素的野外试验。初步结果显示球果花蝇有产卵阻碍信息素作用的存在 ,但还需进一步试验证明 ;同时结果未显示有性引诱效果。     

Endophyte fungus confers resistance to ryegrass: Argentine stem weevil larval studies

ABSTRACT.

• 1 Conferred insect resistance arises from a mutualistic relationship between claviciptaceous endophytic fungi and various grasses. A number of secondary compounds are responsible for the insect resistance. This paper describes studies of the relationship between the endophytic fungus Acremonium lolii Latch, Christensen & Samuels and the Argentine stem weevil Listronotus bonariensis (Kuschel) (Curculionidae); in particular, the effects on larval feeding behaviour, growth and survival.
• 2 Larvae are stem borers. Tunnel length and distance bored into the basal sheath zone of ryegrass was reduced when the plants were infected by A. lolii.
• 3 Lolitrem B, a potent mammalian neurotoxin, levels were highest in A. lolii infected grasses and ranged from 2.61 to 7.08 μg/g dry wt, the higher value being recorded in summer.
• 4 Lolitrem B extracted from A. lolii-infected perennial ryegrass reduced larval growth rates and survival.
• 5 Lolitrem B acted via the insect stomach rather than by absorption through the integument.
• 6 The potential role of endophytic fungi in plants is discussed briefly in relation to herbivory.

     

稻水象甲田间种群动态及化学控制技术

稻水象甲在福建省霞浦县长春镇田间种群发生动态的调查结果表明:5月中旬是稻水象甲越冬代成虫迁入稻田为害高峰期,5月下旬成虫种群数量迅速降低,并有少量幼虫开始为害水稻根部;6月初是幼虫发生为害高峰期,蛹高峰期出现在6月中旬,并开始有一代成虫羽化。药剂筛选试验结果表明:20%丁硫克百威乳油、48%毒死蜱乳油、40%三唑磷乳油、5%锐劲特悬浮剂对稻水象甲成虫具有良好的田间控制效果,药后7d防效均在92.31%—100%;5%丁硫克百威颗粒剂、15%乐斯本颗粒剂、3%呋喃丹颗粒剂施药后7d对稻水象甲幼虫的防效90.03%—93.56%。化学综合防治示范区水稻分蘖数和株高均显著大于对照区。     

Optimization of a chemical attractant for Epicometis (Tropinota) hirta Poda

In field trapping tests in Hungary cinnamyl alcohol (3-phenyl-2-propen-l-ol) and transanethole [(1-methoxy-4-(1-propenyl)benzene)] attracted significantly more adult Epicometis (Tropinota) hirta (Coleoptera, Scarabaeidae, Cetoniinae) when presented together in the same bait compared to the single compounds Best attraction was recorded by a 1:1 mixture. Addition of other common floral scent compounds, ie. 3-methyl eugenol, 4-methoxy-cinnamaldehyde, anisylacetone, beta-ionone, cinnamyl acetate, cinnamic aldehyde, eugenol, indole, 2-phenylethanol or phenylacetaldehyde did not influence catches. The binary cinnamyl alcohol/trans-anethole bait described in this study is recommended for use in traps of E. hirta for agricultural purposes.