Factors affecting field performance of pheromone traps for tobacco beetle, <Emphasis Type="Italic">Lasioderma serricorne</Emphasis>, and tobacco moth, <Emphasis Type="Italic">Ephestia elutella</Emphasis>

Tobacco beetle, Lasioderma serricorne (F.) (Coleoptera: Anobiidae), is one of the most serious insect pests of stored tobacco, and traps baited with the female-produced sex pheromone, serricornin, are used for monitoring the pest. In two trapping experiments carried out in tobacco warehouses in Greece, two commercially available trap and lure systems for L. serricorne were found to be equally effective in terms of the numbers of beetles trapped. In contrast to previous reports, anhydroserricornin was unattractive and lures containing serricornin and anhydroserricornin were less attractive than lures containing serricornin only. The sex pheromone of the other main insect pest of tobacco, Ephestia elutella (Hübner) (Lepidoptera: Pyralidae), could be added to the lures without affecting the attractiveness of either pheromone to their respective species. Lures remained attractive for at least 4 weeks under field conditions, and, in laboratory tests, release of pheromone could still be detected after 30 days at 27 °C. The stereoisomeric composition of the serricornin in the two commercial lures was similar with high proportions of the attractive (4S,6S,7S)-isomer. The proportion of the (4S,6S,7R)-isomer was low, and this is known to reduce the attractiveness.     

Untersuchungen über die Verwendung von Pheromonfallen als Befallsindikatoren bei einigen vorratsschädlichen Zünslerarten (Lep., Pyraloidea)

In the Summer of 1983 experiments were carried out on moth trapping by help of pheromone baited traps (Detia moth indicators) in seven warehouses in West-Berlin (stocks: cocoa beans, dried vegetables and spices).Ephestia cautella (Walker),E. elutella (Hübner),E. kühniella Z. andPlodia interpunctella (Hübner) were caught. The traps baited with the pheromone TDA caught many times more moths than control traps did. So they seem especially suited as indicators for a slight infestation.     

Some aspects of the sexual behaviour of the Lepidoptera Pyralidae infesting stored-products

Research on moth sexual behaviour has focused primarily on female pheromones and male behavioural responses to them. Although several researches on moth sex pheromones have demonstrated that the complete sequence of courtship behaviour also involves male pheromones and other types of communication, relatively little work has been done on the connection between pheromones and extrusible organs or with sound production. Many insects have airborne sound receptors, which function primarily in intraspecific communication, whilst in others hearing serves to warn a potential threat from a predator. Certain pyralid moths infesting stored food, such as the GalleriinaeAchroia grisella F.,Galleria mellonella L., andCorcyra cephalonica (Staint.), and the PhycitinaeEphestia cautella (Walker),Ephestia kuebniella Zeller andPlodia interpunctella (Hübner) have acquired the additional ability to generate sounds by wing-fanning for intraspecific communication and pair forming. The courtship of these Lepidoptera Pyralidae has been examined and several studies have been made on the male orientation to the pheromone produced by the calling famale and also on the behaviour of the male after the female has been located. The paper gives details on the role of ultrasound production in the courtship behaviour and discusses the role of other signals in pair forming.     

Monitoring of stored tobacco insect pests by means of pheromones: the case ofEphestia elutella (Hübner) andLasioderma serricorne Fabricius in South Europe

Results obtained in the monitoring of stored tobacco pests by pheromones are reported. In GreeceEphestia elutella (Hübner) is likely to have at least 3 generations per year: the first one appears in early May, the second one during the last week of June and the third one— the most populated and the longer lasting—in August. In the same environmentsPlodia interpunctella (Hübner) has shown about 5 generations per year. The first on appeared in late May; the remaining 4—definitely overlapping—are placed in mid-June, in July, in early August and early September. In Italy four commercial pheromone dispensers effective in trappingLasioderma serricorne Fabricius have been compared. The results pointed out highly significant differences of the efficacy of the four different dispensers tested.L. serricorne was present in the tobacco store from June to October with a quite remarkable increase between August and early September.     

Forest pest control by common redstart (Phoenicurus phoenicurus L.) near Antalya, Turkey

This research was conducted in two Mediterranean forest study plots (Bük-Lütfi Büyükyıldırım BL and Elmalı Cedarforest EZ) near Antalya, Turkey, between 2000 and 2002. Adult redstarts fed their nestlings exclusively with insects (79.5%). Three hundred and thirty seven prey items were identified of which 34.4% were Coleoptera, 17.2% Lepidoptera, 11.6% Diplopoda, 9.8% Diptera, 8.0 % Hymenoptera, 5% Heteroptera, 4.7% Arachnida, 2.7% Orthoptera, 1.8% Myriapoda, 1.2% zu Sedantaria, 0.6% each scorpions, Homoptera, and Dermaptera, and 0.3% each Chilopoda, Neuroptera, and earthworms (Lumbricus terrestris). Fourteen different forest pest species were identified of which seven species were Lepidoptera, four Coleoptera, two Hymenoptera and one Orthoptera.     

Bioactivities of <Emphasis Type="Italic">Cocos nucifera</Emphasis> L. (Arecales: Arecaceae) and <Emphasis Type="Italic">Terminalia catappa</Emphasis> L. (Myrtales: Combretaceae) leaf extracts as post-harvest grain protectants against four major stored product pests

Compounds extracted from the leaves of coconut palm, Cocos nucifera L. (Arecales: Arecaceae) and the Indian almond, Terminalia catappa L. (Myrtales: Combretaceae) were assessed as potential grain protectants against four major pests of stored grains, Sitophilus oryzae (L.) (Coleoptera: Curculionidae), Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae), Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), and Callosobruchus chinensis (L.) (Coleoptera: Bruchidae). The crude leaf extracts and their fractions were obtained by solvent elution and bioassayed in the laboratory, focusing on (a) the duration of protection and (b) their effects on progeny production. Results showed that adults of C. chinensis, S. oryzae, and T. castaneum were equally susceptible to the fumigant toxicity of C. nucifera and T. catappa crude extracts as well as their column eluted fractions. On the contrary, adults of R. dominica showed tolerance to all the extracts tested in both fumigation and contact mode bioassays. Cocos nucifera crude extracts were highly effective in offering long-term protection in residual toxicity trials and along with the crude extracts of T. catappa showed strong repellent properties against the tested species except for R. dominica in a Y-tube olfactometer. Generally, the chromatographic fractions of crude leaf extracts eluted with ethyl acetate were significantly more effective than methanol, chloroform or hexane-eluted fractions. Further, all the tested plant extracts demonstrated a negative impact on several biological parameters such as feeding activity and progeny production of the tested species. These results highlight the potential of C. nucifera and T. catapa extracts as potent insecticides, feeding deterrents and progeny production inhibitors and consequently are suitable for the control of pests in stored commodities.     

Arthropod pests and their natural enemies in stored crops in northern Namibia

A survey of stored product pests, their natural enemies, grain storage and pest management approaches in northern Namibia was conducted. The survey revealed five types of crop commodities (pearl millet, sorghum, cowpea, maize, feed mixture) stored in four types of grain stores (baskets, bag stags-flat stores, concrete bin, metal containers). No synthetic pesticides or plastic sheeting was recorded. Wooden-ash natural pesticide is the only protectant used. Ten insect pest species were found affiliated to the orders of Coleoptera (Attagenus fasciatus, Callosobruchus subinnotatus, Cryptolestes ferrugineus, Oryzaephilus surinamensis, Rhyzopertha dominica and Tribolium castaneum), Lepidoptera (Corcyra cephalonica, Sitotroga cerealella), Psocoptera (Liposcelis paeta) and Blattodea (Blattella germanica). Out of these, seven species were recognized as new stored-products pests for Namibia. Although listed for southern Africa region, no storage pest-mites (Acari) and Sitophilus spp., Prostephanus sp. or Trogoderma sp. beetles were traced. We found four new species of natural enemies of storage pests recruiting from insects (Habrobracon hebetor, Cephalonomia wattersoni, Brachymeria sp.) and mites (Blattisocius tarsalis). The occurrence of natural enemies indicates a potential for pest bio-control in Namibian grain stores.     

Über die Fichten-Silbermotten (Lepidoptera, Yponomeutidae, Argyresthiinae) in den Westkarpaten

Three species of the genusArgyresthia Hübner (A. bergiella Ratzeburg,A. amiantella Zeller andA. glabratella Zeller) were studied in Norway spruce forests at an elevation of 380–1550 m in the West Carpathian Mountains (central and western Slovakia). These species have distinct external pupal characteristics and feed marks. They occur together, being more abundant in the middle and upper canopy, and prefer forests at or above 1,000 m, often at the timber line. Their dependence on parent rock was not found. Abundance of these species differed greatly from year to year and any changes in abundance were mostly synchronised at various sites within the same mountain area.A. amiantella was the most abundant species. There is an indication that the outbreaks ofArgyresthia moths on Norway spruce might be short-term.

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Über die Fichten-Silbermotten (Lepidoptera, Yponomeutidae, Argyresthiinae) in den Westkarpaten

     

Insect inhabitants of old larval galleries of<Emphasis Type="Italic"> Saperda populnea</Emphasis> (L.) (Coleoptera: Cerambycidae) in Bulgaria

The complex of insect inhabitants of old larval galleries of Saperda populnea (L.) (Coleoptera: Cerambycidae) was studied during the period 2000–2003 in 18 localities in Bulgaria. As a result, 32 insect species were reared from old S. populnea galls: Metopoplax origani (Kolenati) (Heteroptera: Lygaeidae), Malachius sp. (Coleoptera: Malachiidae), Agrilus pratensis pratensis (Ratzeburg) (Coleoptera: Buprestidae), Xylocleptes bispinus (Duftschmidt) (Coleoptera: Scolytidae), Crossocerus cetratus (Shuckard), Crossocerus megacephalus (Rossi), Crossocerus nigritus (Lepeletier & Brullé), Crossocerus acanthophorus (Kohl), Passaloecus brevilabris Wolf, Passaloecus gracilis (Curtis), Psenulus schencki (Tournier), Solierella compedita compedita (Piccioli), Trypoxylon figulus figulus (Linnaeus), Trypoxylon fronticorne fronticorne Gussakovskij (Hymenoptera: Crabronidae), Cleptes schmidti Linsenmaiser, Trichrysis cyanea (Linnaeus) (Hymenoptera: Chrysididae), Clistopyga incitator (Fabricius), Ctenochira sanguinatoria (Ratzeburg), Liotryphon crassisetus (Thomson), Nemeritis fallax (Gravenhorst), Mesochorus georgievi Schwenke, Campoletis sp. (Hymenoptera: Ichneumonidae), Charmon extensor (Linnaeus) (Hymenoptera: Braconidae), Eupelmus urozonus Dalman (Hymenoptera: Eupelmidae), Perilampus aeneus (Rossius) (Hymenoptera: Perilampidae), Trichiocampus grandis (Lepeletier) (Hymenoptera: Tenthredinidae), Janus luteipes (Lepeletier) (Hymenoptera: Cephidae), Cydia corollana (Hübner) (Lepidoptera: Tortricidae), Fiebrigella brevibucca (Duda) (Diptera: Chloropidae), Eustolomyia hilaris (Fallén) (Diptera: Anthomyiidae), Senotaina sp. (Diptera: Sarcophagidae) and Heringia vitripennis (Meigen) (Diptera: Syrphidae). Amongst them, 27 species were established as new inhabitants of old S. populnea galls. Five species (C. schmidti, N. fallax, M. georgievi, P. aeneus and J. luteipes) were recorded for the first time in Bulgaria. The dwellers of old S. populnea galls belong to the following ecological groups: insects using galls as a place to develop (3 species); insects nidificating in empty galls (10 species); insects using old galls as a pupating place (1 species); insects using empty galls as overwintering shelters (3 species); predators and parasites of primary dwellers of empty galls (13 species); or insects with uncertain ecological status (2 species).     

A laboratory study on the activity of <Emphasis Type="Italic">Steinernema feltiae</Emphasis> (Rhabditida: Steinernematidae) Rioja strain against horticultural insect pests

The potential of the entomopathogenic nematode Steinernema feltiae (Filipjev) (Rhabditida: Steinernematidae) Rioja strain was assessed under laboratory conditions. Last instar larvae of Leptinotarsa decemlineata Say (Coleptera: Chrysomelidae), Spodoptera littoralis Boisdouval (Lepidoptera: Noctuidae) and Trichoplusia ni Hübner (Lepidoptera: Noctuidae) were exposed to infective juveniles (IJs) under laboratory conditions. Larval mortality, days to larval death, infection cycle length, and reproductive potential were recorded. Efficacy was assessed performing dose–response experiments. The results indicate that control of L. decemlineata with S. feltiae Rioja strain is not economically profitable (LC₅₀ = 99.61 IJs/cm²), whereas results obtained for T. ni (LC₅₀ = 0.27 IJs/cm²) are promising. Due to the life cycle of this insect, the efficacy needs to be investigated in foliar application studies. The effects on S. littoralis (LC₅₀ = 0.69 IJs/cm²) was considered the most suitable for development of the Rioja strain as a biocontrol agent for soil application.     

Über die Verbreitung von Bacillus thuringiensis Berl. und einiger Sporozoen-Krankheiten bei vorratsschä dlichen Lepidopteren im Gebiet von Kosova,Jugoslawien

On the distribution of Bacillus thuringiensis Berl. and some Sporozoon diseases of store damaging Lepidoptera in the Kosova region, Yugoslavia The studies concerning the incidence and distribution ofBacillus thuringiensis Berl. and various Sporozoa, such asMattesia dispora Naville (Weiser, 1954),Nosema heterosporum Kellen & Lindengren,Telochania ephestiae Mattes andAdelina mesnili Perez, as well as the quantitative and qualitative relationships of both groups of pathogens to various store product destroying Lepidoptera, were carried out with specimens found in 57 watermills at 22 localities in the are of Kosova, Yugoslavia.A total of 3065 dead and living larvae ofEphestia kühniella infected withBacillus thuringiensis and Sporozoa were examined. Other larvae also examined after infection withB. thuringiensis included specimens ofE. elutella, Plodia interpunctella, Plutella maculipennis andPyralis farinalis.Regarding the relationships of the overall intensity of infection of theE. kühniella larvae to the portion of the insects examined (table 2), the following habitats displayed the highest percentage: Hulaj and Tekuli 100%, Prizreni 86% and Isniqi 80%. The intensity of the larvae infected withB. thuringiensis was highest at Istogu 35%, Radavci 33% and Isniqi 32%. The greatest incidence of Sporozoan infections was in the following habitats: WithMattesia dispora: Kabashi 80% and Strellci 74%; withNosema heterosporum: Peja (Pe) 39% and Rugova 35 %; withAdelina mesnili: Kashica 28%, Strellci and Gjakova 21%.Further data from table 3 indicate that theE. kühniella larvae infected withBacillus thuringiensis were spread relatively widely and evenly throughout all the examined habitats in the area of Kosova. But onlyEphestia kühniella was infected at all of 22 localities.     

The distribution of Phratora vulgatissima (Coleoptera: Chrysomelidae) on cultivated willows in Britain and Ireland

Insect samples were collected from the canopy of 24 willow short rotation coppice (SRC) sites on farmland in Britain and Ireland in 1995. The blue willow beetle Phratora (= Phyllodecta) vulgatissima (L.) (Coleoptera: Chrysomelidae), previously identified as the main defoliating pest of this crop, was recorded from 13 of these at varying levels of abundance. Data describing aspects of the environment at each site were also collected. These data were used to create potential explanatory variables for a regression analysis of beetle abundance. This analysis indicated that P. vulgatissima were most likely to occur and were more abundant at older willow sites on clay soils and at sites that bad certain free-living willow species growing nearby. Within sites, most willow clones sampled contained P. vulgatissima, although two, Salix burjatica‘Germany’ (‘Aquatica Gigantea’) and Salix mollissima‘Q83’ (Salix triandra × Salix viminalis), were avoided. Chrysomelid pest avoidance and clonal resistance could form part of an integrated pest management strategy for SRC crops.     

Effect of host plants on life-history traits of <Emphasis Type="Italic">Spodoptera exigua</Emphasis> (Lepidoptera: Noctuidae)

Host plants play an important role in population increases and outbreaks of cosmopolitan polyphagous insect pest, such as Spodoptera exigua (Hübner; Lepidoptera: Noctuidae). We investigated the impact of various host plants (cauliflower, peas, and wheat) on fitness and relative growth rate of S. exigua and intrinsic rate of population increase. The S. exigua population was collected from cauliflower fields from Multan, Pakistan. Comparison of various life-history traits on three different host plants revealed significant differences that might be correlated with the fitness costs. The mean number of eggs laid by female reared on cauliflower was significantly greater than on peas or wheat. Similarly, eggs viability, intrinsic rate of population increase, adult eclosion, and adult’s longevity were significantly higher on cauliflower than on peas and wheat. The low survival on peas and wheat suggest the unsuitability of these host plants, while the higher pupal weight on cauliflower suggest that it provides better food quality to S. exigua compared with peas and wheat. On peas and wheat, fitness declined with each generation suggesting that the average fitness of individuals may decline due to the elimination of insects with higher fitness. Our results suggest that cauliflower was the most nutritive and preferred host plant. Such results could be useful to design cultural management strategies, which may include trap cropping.     

Beitrag zur Kenntnis der Entomofauna der Fichtenzapfen,Picea abies (L.) Karst. in Norwegen

Zusammenfassung Aus 61 Fichtenzapfen,Picea abies (L.) Karst., gesammelt im September 1985 in Arendal, Norwegen, wurden 20 Arten Insekten (449 Individuen) aus den Ordnungen: Hymenoptera, Lepidoptera und Diptera gewonnen (Tab. 1). Dabei tratGaurax strobilum Karps (Dipt., Chloropidae) als neue Art für Norwegens Fauna auf.Es wird der Schlüpfverlauf vonKaltenbachiola strobi (Winn.) (Dipt., Cecidomyiidae) und seiner Parasiten (Abb. 1) dargestellt, nämlich:Anogmus vala (Walk.) (Pteromalidae),Platygaster contorticornis (Ratz.) (Platygasteridae),Tetrastichus strobilanae (Ratz.) (Eulophidae),Torymus azureus Boh. undT. caudatus Boh. (Torymidae).

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Contribution to the knowledge of entomofauna of the spruce cones,Picea abies (L.) Karst. in Norway

Information on 20 species (a total of 449 individuals) of insects, belonging to orders Hymenoptera, Lepidoptera and Diptera, are given. Insects were obtained from cones of spruce,Picea abies (L.) Karst. collected in Norway in 1985.

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Mit einer Abbildung und einer Tabelle     

Diversity and dominant species of arthropods in different forests of Aershan, Inner Mongolia

Taking different forests in Aershan of Inner Mongolia as sample plots,diversity and dominant species of arthropods were studied.The results show that two classes,17 orders,68 families,130 species and 3742 individuals were identified and 92.31% of total species appeared in natural forests,and 75.38% of total species appeared in plantations.The orders of Lepidoptera,Coleop-tera,Diptera and Hymenoptera covered most of the collected arthropods.In different forest types,diversity indices is natural mixed forests...     

Freilanduntersuchungen zur Nahrungsökologie der Spinnen: Beobachtungen aus der Region Zürich

Zusammenfassung Von 1974–1980 wurden in der Umgebung von Zürich (Schweiz) Beobachtungen über die Nahrungsökologie von Spinnen durchgeführt. Die Resultate lassen sich wie folgt zusammenfassen: Sämtliche untersuchten Spinnenarten fraßen ausschließlich an Evertebraten (Insecta, Arachnida, Isopoda, Myriapoda, Lumbricidae). Bei den meisten untersuchten Spinnen bestand die Nahrung zu>90% aus Insekten. Kleine Fluginsekten (Dipteren, Blattläuse) stellen für zahlreiche Spinnen der Vegetationsschicht die Hauptnahrungsquelle dar. Kleine, weichhäutige Insekten (Collembolen, Blattläuse, Dipteren) sind die Nahrungsbasis der dominanten Spinnen der Bodenoberfläche. Ein vom Durchschnitt abweichendes Beutespektrum besitzen die ArtenArgiope bruennichi (Prädator von Heuschrecken u. Bienen),Xysticus cristatus (epigäisch: Prädator von Ameisen u. Spinnen),Achaearanea riparia (Prädator von Amesien u. Käfern),Coelotes terrestris (Prädator von Käfern),Pholcus phalangioides (Prädator von Asseln, Spinnen, Opilioniden etc.). Die untersuchten Spinnenarten weisen unterschiedlich breite Nahrungsspektren auf. So ist beispielsweise das Nahrungsspektrum bei den Trichterspinnen der GattungAgelena weit aufgefächert (polyphag). Im Vergleich dazu hat die TrichterspinneC. terrestris ein enges Beutespektrum (oligophag). Während bei den meisten Spinnenarten die Beutegröße der Räubergröße angepaßt ist (Beutegröße Räubergröße), erlegen einige Spinnenarten (v. a. Familien Thomisidae und Theridiidae) gelegentlich Beutetiere, die größer als sie selber sind. Die Spinnen sind überwiegend Sekundärkonsumenten innerhalb von Herbivoren-Nahrungsketten. Die auf Waldböden lebenden Wolfspinnen greifen zusätzlich auch in Detritus-Nahrungsketten ein. In Flußuferbiotopen ernähren sich Skorpionsfliegen (GattungPanorpa) häufig von Beutetieren in Spinnennetzen (Nahrungsdiebstahl).

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Field studies on the feeding ecology of spiders: Observations in the region of Zurich (Switzerland)

The results of studies on the feeding ecology of spiders from 1974–1980 can be summed up as follows: All species of spiders examined fed exclusively on evertebrates (Insecta, Arachnida, Isopoda, Myriapoda, Lumbricidae). In most cases, more than 90% of the food consisted of insects.Numerous spiders living in the vegetation stratum feed mainly on small flying insects, such as Diptera and aphids. The same is true for the dominant spiders living on the surface of the soil, though their prey spectrum is supplemented by Collembola and apterous aphids. Thus in the average prey spectrum of spiders small insects with a soft cuticle dominate. Exceptions are found withArgiope bruennichi, a predator of grasshoppers and bees,Agelena spp. feeding mainly on relatively large insects,Xysticus cristatus, which, when hunting on the ground, preys on ants and spiders,Achaearanea riparia, preying on ants and beetles,Coelotes terrestris, a specialized predator of beetles, andPholcus phalangioides, preying on wood-lice, spiders, opilionides etc. The prey spectra of the spider species examined vary considerably in breadth. So the food spectrum of the funnel-web spiders of the polyphagous genusAgelena is large compared to that of the oligophagousC. terrestris. Whereas in most spider species the size of their prey is relatively small or only reaches the size of the predator (size of prey size of predator), some species, mainly of Thomisidae and Theridiidae, prey at times upon prey larger than they are.Spiders are secondary consumers belonging predominantly to herbivor food chains. Wolf spiders living on forest grounds intervene also in detritus food chains. Scorpionflies (genusPanorpa) often feed on prey animals in spider webs (food robbery).

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Ausgeführt mit Unterstützung durch den Schweizerischen Nationalfonds zur Förderung der Wissenschaftlichen Forschung.     

A survey of the Agrothereutes hospes, an ectoparasitoid on wax moth Galleria mellonella

Agrothereutes hospes (Tschek.) (Ichneumonidae, Cryptinae), a solitary ectoparasitoid, is redescribed. Details of tyloids on male flagellum are presented and discussed. Investigations on the development of the parasitoid on wax moth host Galleria mellonella (L.) (Lepidoptera) were made. Longevity of A. hospes females is between 10 days and 40 days, while in males it is 7–20 days. The egg productivity and the hatching of eggs were in maximum between 6 days and 15 days. The maximal pupae ratio was between 1 days and 15 days, and average of sex ratio was 2:1.     

Einsatz von Prallmaschinen zur Bekämpfung der MehlmotteEphestia kuehniella Zeller (Lepidoptera: Pyralidae) in Mehl und Grieß

Zusammenfassung Durch den Einsatz eines Doppelrotors konnte die Durchsatzleistung beim Prallvorgang von Mehlen von 7 t/h auf 12 t/h bei gleichzeitiger vollständiger Abtötung der Eier vonEphestia kuehniella gesteigert werden.Bei der Prallung von Grießen in Prallmaschinen kann durch Verringerung der Umlaufgeschwindigkeiten der Prallbolzen eine unerwünschte Verfeinerung des Produktes vermieden werden. Eine Abtötung von Mehlmotteneiern ist bei Leistungen von mindestens 12 t/h weiterhin gewährleistet.

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Use of impact machines to control the Mediterranean Flour MothEphestia kuehniella (Lepidoptera: Pyralidae) in flour and semolina

By using a double rotor system in impact machines for flour treatment the capacity can be increased from 7 t/h to 12 t/h and still showing 100% mortality of eggs from the Mediterranean Flour MothEphestia kuehniella.By semolina treatment in impact machines the velocity of the bolts can be reduced to insure that the granulation of the treated product is not influenced to an unacceptable degree. A 100% kill ofE. kuehniella eggs can be reached for a capacity of at least 12 t/h.

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Mit 3 Tabellen     

Insect pests of some exotic and indigenous browse species in southeastern Nigeria

During the period February to July 1992 the incidence of attacks by insect pests on ten cultivated browse species was studied at Obio Akpa, located in humid southeastern Nigeria. Two of the browse speciesGliricidia sepium andLeucaena leucocephala were exotic and eightAlchornia cordifolia, Baphia nitida, Rauvolfia vomitoria, Diallum guineensis, Ficus capensis, Glyphaea brevis, Homalium aylmeri andManniophytum fulvum indigenous. Forty insect pests were collected and 33 identified. Those identified belonged to either the order Coleoptera, Heteroptera, Lepidoptera or Orthoptera. Some of the insects were browse-specific, while others attacked several browse species. None of the browse species was free from insect attacks.     

Asymmetry of mating behaviour affects copulation success in two stored-product beetles

Lateralization (i.e. left–right asymmetries in the brain and behaviour) has been documented in all vertebrate classes, while evidences for invertebrates are limited. To the best of our knowledge, there is no information about behavioural asymmetries in the order Coleoptera. In this research, we investigated the lateralization of mating traits in two major pests of stored products: the rice weevil, Sitophilus oryzae (Coleoptera: Curculionidae), and the confused flour beetle, Tribolium confusum (Coleoptera: Tenebrionidae). Both T. confusum and S. oryzae males showed population-level left-biased copulation approaches of potential mates. Interestingly, T. confusum and S. oryzae males performing left-biased copulation attempts achieved higher mating success over right-biased males. Furthermore, S. oryzae males periodically exhibited a typical head wagging behaviour, which consists of waving the rostrum laterally across the female thorax and then resting the rostrum on the mid thorax. This behaviour was right-biased, even in the majority of males that previously showed left-biased copulation attempts. The quantification of mating displays could allow comparisons with other strains, in order to evaluate the impact of a given host or of the rearing methods on the mating traits of S. oryzae and T. confusum. Overall, this is the first report of lateralization of mating traits in Coleoptera. Furthermore, this research adds basic knowledge to the reproductive behaviour of S. oryzae and T. confusum.