DOCSLIB.ORG

Predation Upon Adalia Bipunctata and Harmonia Axyridis Eggs by Chrysoperla Carnea Larvae and Orius Laevigatus Adults

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Predation Upon Adalia Bipunctata and Harmonia Axyridis Eggs by Chrysoperla Carnea Larvae and Orius Laevigatus Adults Bulletin of Insectology 59 (1): 53-58, 2006 ISSN 1721-8861 Predation upon Adalia bipunctata and Harmonia axyridis eggs by Chrysoperla carnea larvae and Orius laevigatus adults Fabrizio SANTI, Stefano MAINI Dipartimento di Scienze e Tecnologie Agroambientali - Entomologia, Università di Bologna, Italy Abstract Intra-guild predation (IGP) between sucking predators in relation to eggs of the exotic ladybird Harmonia axyridis (Pallas) and native Adalia bipunctata (L.) (Coleoptera Coccinellidae) was studied in laboratory. The green lacewing Chrysoperla carnea (Ste- phens) (Neuroptera Chrysopidae) and the pirate bug Orius laevigatus (Fieber) (Rhynchota Anthocoridae) may share the same niche as the two Coccinellidae species. Intra-guild predation may occur in glasshouses and crops when several predator species are used in integrated releases for the biocontrol of arthropod pests. In experimental arenas, the two sucking predators were individu- ally offered the choice between eggs of the two ladybird species. Adult O. laevigatus reared on frozen Ephestia kuehniella Zel- ler eggs were not seen to feed on ladybird eggs, and immediately rejected this kind of food. Conversely, C. carnea larvae at- tacked the ladybird eggs without showing a preference for either species, although we observed that the A. bipunctata eggs were either completely eaten or more shrivelled than those of H. axyridis. In prey suitability experiments, C. carnea larvae that were allowed to develop by being fed an ad libitum supply of A. bipunctata eggs took longer to develop and had a lower survivorship compared to data (from literature) on E. kuehniella frozen eggs. H. axyridis eggs were not suitable for the larval development of C. carnea. We discuss the relevance of these results and intra-guild predation to the use of these species as biocontrol agents. Key words: green lacewing, multicoloured Asian ladybird, two spotted ladybird, pirate bug, intra-guild predation, IGP, Ephestia kuehniella. Introduction teractions between polyphagous predators. Inoculative or augmentative releases and the side effects of intro- Intra-guild predation (IGP) represents an extreme form ducing exotic generalist predators are other issues that of competition between species (Polis et al., 1989). require accurate analyses (van Lenteren et al., 2003). In When an insect predator from a specific trophic level at- Italian agroecosystems, the biological and IPM control tacks another entomophagous arthropod from the same techniques recommend the use of the larvae of the green trophic level, and both species eat the same prey or fight lacewing Chrysoperla carnea (Stephens) (Neuroptera each other, we can define this interaction as intra-guild Chrysopidae) and several species of ladybirds (Coleop- predation (Polis and Holt, 1992). At low densities, poly- tera Coccinellidae) as a means of controlling aphids, phagous predators may eat common prey such aphids, combined with the pirate bug Orius laevigatus (Fieber) lepidopteran eggs, and larvae, but when prey and (Rhynchota Anthocoridae) as a means of controlling predator densities increase, the predators may also show thrips. These beneficial species are commercially avail- negative intraspecific interactions such as cannibalism able from European biofactories. The exotic Asian la- (Coderre et al., 1987; Majerus, 1994, Lucas et al., 1997; dybird Harmonia axyridis (Pallas) is a potential com- Hironori and Katsuhiro, 1997; Burgio et al., 2002; Santi petitor of native Coccinellidae, but is not yet established et al., 2003; Burgio et al., 2005). Within the community, in Italy (as far as we know), which may in part be be- predation risk of individuals depends upon a large range cause releases of this species in greenhouses and the of factors: the risk experienced may be reduced with an open field have been stopped. Recently, the flightless increase in body size as observed in Orius spp. by strain (Gil et al., 2004) has been reared and commer- Tommasini et al. (2002), but this risk is also dependent cially produced for the biological control of aphids in upon factors such as their mobility and the semiochemi- French greenhouses. The two spotted ladybird A. cals (allomones) that they produce as demonstrated in bipunctata is another candidate for augmentative re- Coccinellidae (Felix and Soares, 2004; Omkar et al., leases in Italy and other regions of Europe (Kehrli and 2004). The egg masses of ladybirds are generally not Wyss, 2001). The mouthparts of C. carnea larvae and O. protected externally, and therefore can be easily preyed laevigatus nymphs and adults allow these species to per- upon (Polis et al., 1989). However, Hemptinne et al. forate the egg chorion, and then suck the contents from (2000) found that some alkaloids are present in Adalia the egg. In commercial insectaries, C. carnea larvae and bipunctata (L.) and Coccinella septempunctata L. eggs, O. laevigatus are usually reared on the same artificial which may contribute to reducing intra-guild predation prey, i.e. the frozen eggs of Ephestia kuehniella Zeller. as in other ladybird species (Omkar et al., 2004). The intra-guild predation between C. carnea and O. When beneficial insects are released as biocontrol laevigatus has not been investigated previously because agents into agroecosystems and habitats such as pro- they rarely interact in the environment, due to their dif- tected crops, it is important to evaluate the possible in- fering modes of egg deposition (i.e. inside the vegetal Class 1 Class 2 A B Class 3 Class 4 Figure 1. Classes of feeding effects by C. carnea larvae on ladybird eggs (A: H. axyridis; B: A. bipunctata). tissues the pirate bugs and on stalk the green lacewing), The experimental arena was a 12 cm diameter glass but these species may be competitors for opportunities Petri dish. The border of the dish was treated with 5 mm to feed upon eggs. In the open field, O. laevigatus, C. of Teflon to stop the predators escaping. Inside the dish, carnea and A. bipunctata are found in the same weeds 10 fresh eggs of A. bipunctata and 10 of H. axyridis and shrubs nearest to the crops, and therefore these were placed alternately on a filter paper grid of 20 predators are the major contributors to the natural con- points (5 x 4 points separated at 16 x 14 mm distance). trol of insect pests in Italian agroecosystems (Burgio et The eggs were gently removed from a fresh egg cluster al., 2004; Tommasini, 2004). using a smooth brush. The aim of this study was to investigate in the labora- 25 second instar and 25 third instar C. carnea larvae tory the intra-guild predation between sucking generalist were individually released into the arena after being predators (C. carnea and O. laevigatus) in relation to starved for 24 hours. After introduction, the behaviour the exotic species H. axyridis and the indigenous spe- of the larvae was observed for two hours under a bin- cies A. bipunctata. ocular microscope. The behaviour of the larvae to the eggs was designated using the following categories (figure 1): Materials and methods Class 1: the egg was rejected without mouth parts being inserted; The two ladybird species were reared in the laboratory Class 2: mouth parts were inserted, but the egg was under the conditions described by Burgio et al. (2002) immediately rejected; and Santi et al. (2003). The predators C. carnea and O. Class 3: mouth parts were inserted, with some of the laevigatus were supplied by a commercial producer egg contents eaten; (Bioplanet, Cesena, Italy). Class 4: mouth parts were inserted, with most or all of the egg contents eaten, or the egg ended up totally Choice tests of C. carnea larvae and ladybird egg shrivelled. species The number of rejected and attacked eggs (including Experiments were performed as choice tests in a rear- the eggs partially or totally eaten) according to the ing room at temperature of 25 °C ± 2, 60-70 RH, and above mentioned classes, was analysed using a signed light 300-400 lux. rank Wilcoxon non-parametric test. 54 1.2 2.5 Adalia eggs ns Adalia eggs Harmonia eggs 1.0 z=0.48 Harmonia eggs 2.0 0.8 ns gs g gs ns e g z=0 51 . 1.5 e z=0.52 o . o 0.6 N N n a 1.0 e an e 0.4 M M ns 0.5 0.2 z=0.40 0.0 0.0 Attacked Class1 Attacked Class1 rejected rejected Figure 2a. Choice test between the two species of lady- Figure 3a. Choice test between the two species of lady- bird eggs (A. bipunctata and H. axyridis) and second bird eggs (A. bipunctata and H. axyridis) and third in- instar larvae of C. carnea. star larvae of C. carnea. n.s.: P > 0.05 (Wilcoxon signed rank non-parametric n.s.: P > 0.05 (Wilcoxon signed rank non-parametric test, data given as mean ± S.E.). test, data given as mean ± S.E.). 0.6 1.6 Adalia eggs Adalia eggs Harmonia eggs 1.4 Harmonia eggs * 0.5 * z=3,2 z=2.12 * 1.2 z=2,66 gs * gs g z=2,07 0.4 g e 1.0 e . o o N ns 0.3 N 0.8 z=0 an an e ns e 0.6 M 0.2 M z=1,24 0.4 0.1 0.2 0.0 0.0 Class 2 Class 3 Class 4 Class 2 Class 3 Class 4 Figure 2b. Choice test between the two species of lady- Figure 3b. Choice test between the two species of lady- bird eggs attacked (A. bipunctata and H. axyridis) and bird eggs attacked (A. bipunctata and H. axyridis) and second instar larvae of C. carnea. third instar larvae of C. carnea. *: P < 0.05; n.s.: P > 0.05 (Wilcoxon signed rank non- *: P < 0.05; n.s.: P > 0.05 (Wilcoxon signed rank non- parametric test, data given as mean ± S.E.).
Load more

Recommended publications
  • Intra-Guild Predation and Cannibalism of Harmonia Axyridis and Adalia Bipunctata in Choice Conditions
    Bulletin of Insectology 56 (2): 207-210, 2003 ISSN 1721-8861 Intra-guild predation and cannibalism of Harmonia axyridis and Adalia bipunctata in choice conditions Fabrizio SANTI, Giovanni BURGIO, Stefano MAINI Dipartimento di Scienze e Tecnologie Agroambientali - Entomologia, Università di Bologna, Italy Abstract A laboratory experiment was carried out to examine intra-guild predation and cannibalism of exotic Harmonia axyridis (Pallas) and the native species Adalia bipunctata L. (Coleoptera Coccinellidae) in choice condition. Experiments were carried out in glass petri dishes at 25°C, 70% RH, using a 5x4 grid with 10 eggs of exotic and 10 of natives arranged alternatively. One larva or adult of coccinellid was put in the arena and was observed for one hour. Each experiment was replicated 15 times. H. axyridis larvae and adults, and A. bipunctata adults, showed a preference to prey and eat their own eggs rather than interspecific eggs; these dif- ferences were detected for both naive and experienced females and larvae. For A. bipunctata larvae no differences were observed between IGP and CANN in choice conditions. The results indicate a tendency for both species to attack and eat their own eggs rather than interspecific eggs. The risk of introduction of exotic generalist predators is discussed, with particular attention to coc- cinellids. Laboratory experiments on intra-guild predation could give a preliminary indication of the potential for competition between an exotic ladybird and a native one. Key words: Adalia bipunctata, cannibalism, choice test, Harmonia axyridis, intra-guild predation, biological control. Introduction cinellidae) were examined in laboratory experiments in no choice condition on eggs and on larvae (Burgio et The Asiatic polyphagous ladybird Harmonia axyridis al., 2002; Burgio et al., submitted for publication).
    [Show full text]
  • THE USE of a WINGLESS TWO SPOT LADYBIRD Adalia Bipunctata (Coleoptera: Coccinellidae) AS a BIOLOGICAL CONTROL AGENT of APHIDS
    THE USE OF A WINGLESS TWO SPOT LADYBIRD Adalia bipunctata (Coleoptera: Coccinellidae) AS A BIOLOGICAL CONTROL AGENT OF APHIDS Ana Rita Chico Registration nr 770531 004 100 MSc. Organic Agriculture ENT 80439- Thesis Entomology Supervisor: Peter de Jong Examiner: Marcel Dicke Chairgroup Entomology Wageningen University Wageningen UR “If we knew what we were doing, it would not be called research, would it?” Albert Einstein 2 THE USE OF A WINGLESS TWO SPOT LADYBIRD Adalia bipunctata (Coleoptera: Coccinellidae) AS A BIOLOGICAL CONTROL AGENT OF APHIDS A.R. Chico November 2005 Chairgroup Entomology Wageningen University Binnenhaven 7 6709 PD, Wageningen 3 TABLE OF CONTENTS PREFACE.............................................................................................................................................................. 5 1. INTRODUCTION............................................................................................................................................. 6 1.1. BIOLOGICAL CONTROL OF APHIDS WITH PREDATORY LADYBIRDS ................................................................ 6 1.1.1. Ladybirds- an introduction.................................................................................................................. 6 1.1.2. Ladybirds as biological control agents of aphids................................................................................ 7 1.2. BACKGROUND STORY ON THE WINGLESS LADYBIRD .................................................................................... 8 1.3. SCIENTIFIC
    [Show full text]
  • Predation of Adalia Tetraspilota (Hope) (Coleoptera: Coccinellidae) on Green Peach Aphid (Myzus Persicae
    & Herpeto gy lo lo gy o : h C it u n r r r e O n Joshi et al., Entomol Ornithol Herpetol 2012, 1:1 , t y R g e o l s DOI:10.4172/2161-0983.1000101 o e a m r o c t h Entomology, Ornithology & Herpetology n E ISSN: 2161-0983 ResearchResearch Article Article OpenOpen Access Access Predation of Adalia tetraspilota (Hope) (Coleoptera: Coccinellidae) on Green Peach Aphid (Myzus persicae. Sulzer) Joshi PC2*, Khamashon L2 and Kaushal BR1 1Department of Zoology, D.S.B. Campus Kumaun University, Nainital, Uttarakhand, India 2Department of Zoology and Environmental Sciences, Gurukula Kangri University, Haridwar, India Abstract Studies on prey consumption of larvae and adults of Adalia tetraspilota (Hope) (Coleoptera: Coccinellidae) was conducted in the laboratory on green peach aphid, Myzus persicae (Sulzer) (Homoptera: Aphididae). In larval form 4th instar was the most efficient consumer with an average of 39.96 ± 1.04 aphids larva-1day-1 followed by 3rd instar with an average of 20.90 ± 0.58 larva-1day-1. Feeding potentials of adult coccinellids increased with increase in age. In female the highest consumption of aphids was recorded on the 23rd day of its emergence while in case of male it was recorded on 24th day. Female adult consumed more aphids (39.83 ± 11.39 aphids day-1) than male (31.70 ± 8.07 aphids day-1). Keywords: Coccinellidae; Adalia tetraspilota; Myzus persicae; Larva; Instar Age Number of aphids consumed Adult male; Adult female; Feeding (days) V1 V2 V3 V4 Mean ± SD First 1 2 3 3 2 2.50 ± 0.58 Introduction 2 4 4 5 5 4.50 ± 0.57 Mean 3 ± 1.41 3.5 ± 0.71 4 ± 1.41 3.5 ± 2.21 3.50 ± 0.41 Biological control is a component of integrated pest management Second 3 8 8 7 7 7.50 ± 0.57 strategy which consists of mostly the natural enemies of insect pests 4 10 11 11 12 11.00 ± 0.82 5 11 12 14 14 12.75 ± 1.5 i.e, predators, parasitoids and pathogen.
    [Show full text]
  • Arthropod Pest Management in Greenhouses and Interiorscapes E
    Arthropod Pest Management in Greenhouses and Interiorscapes E-1011E-1011 OklahomaOklahoma CooperativeCooperative ExtensionExtension ServiceService DivisionDivision ofof AgriculturalAgricultural SciencesSciences andand NaturalNatural ResourcesResources OklahomaOklahoma StateState UniversityUniversity Arthropod Pest Management in Greenhouses and Interiorscapes E-1011 Eric J. Rebek Extension Entomologist/ Ornamentals and Turfgrass Specialist Michael A. Schnelle Extension Ornamentals/ Floriculture Specialist ArthropodArthropod PestPest ManagementManagement inin GreenhousesGreenhouses andand InteriorscapesInteriorscapes Insects and their relatives cause major plant ing a hand lens. damage in commercial greenhouses and interi- Aphids feed on buds, leaves, stems, and roots orscapes. Identification of key pests and an un- by inserting their long, straw-like, piercing-suck- derstanding of appropriate control measures are ing mouthparts (stylets) and withdrawing plant essential to guard against costly crop losses. With sap. Expanding leaves from damaged buds may be tightening regulations on conventional insecti- curled or twisted and attacked leaves often display cides and increasing consumer sensitivity to their chlorotic (yellow-white) speckles where cell con- use in public spaces, growers must seek effective tents have been removed. A secondary problem pest management alternatives to conventional arises from sugary honeydew excreted by aphids. chemical control. Management strategies cen- Leaves may appear shiny and become sticky from tered around
    [Show full text]
  • References Affiliations
    Cover Page The handle http://hdl.handle.net/1887/20872 holds various files of this Leiden University dissertation. Author: Lommen, Suzanne Theresia Esther Title: Exploring and exploiting natural variation in the wings of a predatory ladybird beetle for biological control Issue Date: 2013-05-16 References Abouheif E (2004) A framework for studying the evolution of gene networks underlying polyphenism: insights from winged and wingless ant castes. In: Hall BK (ed) Environment, development, and evolution. MIT Press, pp. 125-137 Abouheif E, Wray GA (2002) Evolution of the gene network underlying wing polyphenism in ants. Science 297:249-252 Adachi-Hagimori T, Shibao M, Tanaka H, Seko T, Miura K (2011) Control of Myzus persicae and Lipaphis erysimi (Hemiptera: Aphididae) by adults and larvae of a flightless strain of Harmonia axyridis (Coleoptera: Coccinellidae) on non-heading Brassica cultivars in the greenhouse. BioControl 56:207-213 Agarwala BK, Dixon AFG (1992) Laboratory study of cannibalism and interspecific predation in ladybirds. Ecol. Entomol. 17:303-309 Anbesse SA, Strauch O, Ehlers R-U (2012) Genetic improvement of the biological control nematode Heterorhabditis bacteriophora (Rhabditidomorpha: Heterorhabditidae): heterosis effect enhances desiccation but not heat tolerance. Biocontrol Sci. Technol. 22:1035-1045 Arnaud L, Spinneux Y, Haubruge E (2003) Preliminary observations of sperm storage in Adalia bipunctata (Coleoptera : Coccinellidae): sperm size and number. Appl. Entomol. Zoolog. 38:301-304 Atallah J, Dworkin I, Cheung U, Greene A, Ing B, Leung L, Larsen E (2004) The environmental and genetic regulation of obake expressivity: morphogenetic fields as evolvable systems. Evol. Dev. 6:114-122 Bakker FM, Klein ME, Mesa NC, Braun AR (1993) Saturation deficit tolerance spectra of phytophagous mites and their phytoseiid predators on cassava.
    [Show full text]
  • Temperature-Dependent Development of the Two-Spotted Ladybeetle
    Journal of Insect Science: Vol. 10 | Article 124 Jalali et al. Temperature-dependent development of the two-spotted ladybeetle, Adalia bipunctata, on the green peach aphid, Myzus persicae, and a factitious food under constant temperatures Mohammad. Amin. Jalali1,2, Luc Tirry1, Abbas Arbab3 and Patrick De Clercq1a 1Department of Crop Protection, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium 2Current Address: Department of Crop Protection, Vali-e Asr University, P.O.Box 771393641, Rafsanjan, Iran 3Department of Plant Protection, Islamic Azad University, Takestan Branch P.O. Box: 34819-49479 Takestan- IRAN Abstract The ability of a natural enemy to tolerate a wide temperature range is a critical factor in the evaluation of its suitability as a biological control agent. In the current study, temperature- dependent development of the two-spotted ladybeetle A. bipunctata L. (Coleoptera: Coccinellidae) was evaluated on Myzus persicae (Sulzer) (Hemiptera: Aphididae) and a factitious food consisting of moist bee pollen and Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs under six constant temperatures ranging from 15 to 35° C. On both diets, the developmental rate of A. bipunctata showed a positive linear relationship with temperature in the range of 15-30° C, but the ladybird failed to develop to the adult stage at 35° C. Total immature mortality in the temperature range of 15-30° C ranged from 24.30-69.40% and 40.47-76.15% on the aphid prey and factitious food, respectively. One linear and two non- linear models were fitted to the data. The linear model successfully predicted the lower developmental thresholds and thermal constants of the predator.
    [Show full text]
  • Polymorphism in the 2-Spot Ladybird, Adalla Bipunctata (Coleoptera, Coccinellidae)
    Heredity 70(1993)172—178 Received 5 June 1992 Genetical Society of Great Britain Sperm competition and melanic polymorphism in the 2-spot ladybird, Adalla bipunctata (Coleoptera, Coccinellidae) PETER W. DE JONG*, MICHELLE D. VERHOOG & PAUL M. BRAKEFIELD Section of Evolutionary Biology, Department of Population Biology, University of Leiden, Schelpenkade 14a, 2313 ZT Leiden, The Netherlands Spermprecedence was investigated in the 2-spot ladybird, Ada/ia bipunctata by utilizing a di-allelic colour marker gene. Non-melanic (homozygous recessive) virgin females were mated once with a non-melanic male and after subsequent laying of fertile eggs they were mated with a melanic male of known genotype. Frequencies of colour morphs in the offspring provided evidence for almost complete second male sperm precedence, although the data from certain matings do not completely exclude the possibility of first male sperm precedence. The results are discussed in the light of the hypothesis of thermal melanism. Keywords:Ada/iabipunctata, female rejection, sexual selection, sperm competition, thermal melanism. Introduction mined by a dominant allele (Lus, 1928, 1932; M. E. N. Majerus & P. M. Brakefield, unpublished data), are Spermcompetition has been defined as the competi- black with red spots. Field data have provided tion within a single female between sperm from two or evidence for different forms of sexual selection as so- more males for the fertilization of the ova (Parker, ciated with the different colour morphs: (i) a female 1970). It is, therefore, of particular significance in preference for melanic males has been described in species in which females mate more than once. Many some British populations (Majerus et at., 1982; different patterns of sperm use in the successful fertili- O'Donald & Majerus, 1988; but see Kearns et al., zation of eggs from different male mating partners have 1990, 1992); (ii) a frequency-dependent mating advan- been described in insects (Walker, 1980; Thornhill & tage for melanics has been recorded (Muggleton, 1979; Alcock, 1983).
    [Show full text]
  • Quoted, May Be Found in Marriner (1926, 1939A and B), Bayford (1947), Allen (Sg) and Conway (1958)
    GEOGRAPHIC VARIATION IN THE TWO-SPOT LADYBiRD IN ENGLAND AND WALES E. R. CREED Genetics Laboratory, DepartmentofZoology, Oxford Received6.v.65 1.INTRODUCTION Twoof the most variable species of ladybird in this country are Adalia bipunctata and A. decempunctata. Hawkes (5920, 5927) drew attention to the differences in frequency of the varieties of A. bipunctata in this country, mainly around Birmingham; she found that the black forms predominated in the city while they were less common or rare else- where. In London the black forms comprised only a few per cent, of the population. Further information, though figures are not always quoted, may be found in Marriner (1926, 1939a and b), Bayford (1947), Allen (sg) and Conway (1958). Theinsect has also attracted attention in Europe, but more so in some countries than others. It was in this species that Timofeeff- Ressovsky (i 94oa, i 94ob) demonstrated the action of strong selection in Berlin. He found that the black varieties had a higher mortality than the red during hibernation, but that their relative numbers increased again during the summer. Lusis (ig6i) has reviewed the distribution of the varieties of A. bipunctata in Europe and western Russia and suggests that two conditions tend to favour the black ones: (x) in places with a maritime, more humid climate the percentage of black forms in the populations of Adalia bipunctata L. is as a rule higher than in places with a more continental climate, and (2) in large cities, especially in those with highly developed industry, the percentage of black forms irs the adalia-populations is higher than in towns and in the countryside with similar climate." Unfortunately the only figures for the British Isles apparently available to Lusis were those in Hawkes' second paper (5927), and some of these he disregards.
    [Show full text]
  • Is the Coccinellid Adalia Bipunctata
    Hilbeck et al. Environmental Sciences Europe 2012, 24:10 http://www.enveurope.com/content/24/1/10 RESEARCH Open Access A controversy re-visited: Is the coccinellid Adalia bipunctata adversely affected by Bt toxins? Angelika Hilbeck1*, Joanna M McMillan1, Matthias Meier2, Anna Humbel1, Juanita Schläpfer-Miller1 and Miluse Trtikova1 Abstract Background: In 2008/2009, Schmidt and colleagues published a study reporting lethal effects of the microbial Bt toxins Cry1Ab and Cry3Bb on the coccinellid biological control organisms Adalia bipunctata. Based on this study, in concert with over 30 other publications, Mon810 cultivation was banned in Germany in 2009. This triggered two commentaries and one experimental study all published in the journal ‘Transgenic Research’ that question the scientific basis of the German ban or claim to disprove the adverse effects of the Bt toxins on A. bipunctata reported by Schmidt and colleagues, respectively. This study was undertaken to investigate the underlying reasons for the different outcomes and rebuts the criticism voiced by the two other commentaries. Results: It could be demonstrated that the failure to detect an adverse effect by Alvarez-Alfageme and colleagues is based on the use of a significantly different testing protocol. While Schmidt and colleagues exposed and fed larvae of A. bipunctata continuously, Alvarez-Alfageme and colleagues applied an exposure/recovery protocol. When this exposure/recovery protocol was applied to a highly sensitive target insect, Ostrinia nubilalis, the lethal effect was either significantly reduced or disappeared altogether. When repeating the feeding experiments with the Bt toxin Cry1Ab using a combined protocol of both previous studies, again, a lethal effect on A.
    [Show full text]
  • Functional Response of Adalia Tetraspilota (Hope) (Coleoptera: Coccinellidae) on Cabbage Aphid, Brevicoryne Brassicae (L.) (Hemiptera: Aphididae)
    J. Biol. Control, 23(3): 243–248, 2009 Functional response of Adalia tetraspilota (Hope) (Coleoptera: Coccinellidae) on cabbage aphid, Brevicoryne brassicae (L.) (Hemiptera: Aphididae) A. A. KHAN Division of Entomology, Sher–e–Kashmir University of Agricultural Sciences and Technology (K), Shalimar Campus, Srinagar 191121, Jammu and Kashmir, India. E-mail: [email protected] ABSTRACT: A study was conducted to assess the functional response of different life stages of the predacious coccinellid, Adalia tetraspilota (Hope) feeding on various densities of cabbage aphid, Brevicoryne brassicae (L.) under controlled conditions. It revealed that all stages of A. tetraspilota exhibit Type II functional response curve (a curvilinear rise to plateau) as B. brassicae densities increase and the curve predicted by Holling’s disk equation did not differ significantly from the observed functional response curve. The fourth instar larva consumed more aphids (28.40 aphids / day) followed by adult female (25.06 aphids / day), third instar larva (24.06 aphids / day), second instar larva (21.73 aphids / day), adult male (20.06 aphids / day) and first instar (13.06 aphids / day). The maximum search rate with shortest handling time was recorded for fourth instar larva (0.6383) followed by adult female (0.6264). The results suggest that the fourth instar larva are best suited for field releases for the management ofB. brassicae. However, further field experiments are needed for confirming its potential. KEY WORDS: Adalia tetraspilota, Aphididae, Brevicoryne brassicae, Coccinellidae, functional response, handling time, predation, search rates INTRODUCTION (Type I), decreasing (Type II), increasing (Type III). This could further be simplified in terms of density dependence The cabbage aphid, Brevicoryne brassicae (L.) as constant (I), decreasing (II) and increasing (III) rates (Hemiptera: Aphididae) is an important worldwide pest of prey consumption and yield density dependent prey of cruciferous vegetables in temperate region.
    [Show full text]
  • Effects of Food and Temperature on Development, Fecundity and Life-Table Parameters of Adalia Bipunctata (Coleoptera: Coccinellidae) M
    J. Appl. Entomol. Effects of food and temperature on development, fecundity and life-table parameters of Adalia bipunctata (Coleoptera: Coccinellidae) M. A. Jalali, L. Tirry & P. De Clercq Laboratory of Agrozoology, Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium Keywords Abstract Acyrthosiphon pisum, Myzus persicae, alternative vs. essential foods, biological Development, reproduction and life tables of Adalia bipunctata (L.) were control, factitious food, two-spot ladybird studied at three temperatures (19, 23 and 27°C) on a mixture of frozen pollen and Ephestia kuehniella Zeller eggs as a factitious food and on the Correspondence aphids Myzus persicae (Sulzer) and Acyrthosiphon pisum (Harris) as natural Patrick De Clercq (corresponding author), foods. Development time of A. bipunctata on all tested diets decreased Laboratory of Agrozoology, Department of with increasing temperature. Mortality was lowest at 23°C, averaging Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure links 44.5%, 42.6% and 24.3% on factitious food, A. pisum and M. persicae 653, B-9000 Ghent, Belgium. respectively. The shortest developmental time from egg to adult at this E-mail: [email protected] temperature was observed on factitious food (18.55 days). However, the factitious food was inferior to the aphid diets in terms of reproduction, Received: September 16, 2008; accepted: yielding the longest pre-oviposition period, shortest oviposition period March 22, 2009. and lowest fecundity. The mean oviposition rate at 23°C varied from ) 19.94 to 25.03 eggs day 1 on factitious food and M. persicae respectively. doi: 10.1111/j.1439-0418.2009.01408.x The intrinsic rate of increase (rm) on different foods increased with increasing temperature and ranged from a minimum of 0.08 females/ female/day on factitious food (19°C) to a maximum of 0.18 females/ female/day on A.
    [Show full text]
  • Integrative Taxonomy Reveals Hidden Species Within a Common Fungal Parasite of Ladybirds Received: 19 April 2018 Danny Haelewaters 1,2, André De Kesel3 & Donald H
    www.nature.com/scientificreports OPEN Integrative taxonomy reveals hidden species within a common fungal parasite of ladybirds Received: 19 April 2018 Danny Haelewaters 1,2, André De Kesel3 & Donald H. Pfster1 Accepted: 8 October 2018 Our understanding of fungal diversity is far from complete. Species descriptions generally focus on Published: xx xx xxxx morphological features, but this approach may underestimate true diversity. Using the morphological species concept, Hesperomyces virescens (Ascomycota, Laboulbeniales) is a single species with global distribution and wide host range. Since its description 120 years ago, this fungal parasite has been reported from 30 species of ladybird hosts on all continents except Antarctica. These host usage patterns suggest that H. virescens could be made up of many diferent species, each adapted to individual host species. Using sequence data from three gene regions, we found evidence for distinct clades within Hesperomyces virescens, each clade corresponding to isolates from a single host species. We propose that these lineages represent separate species, driven by adaptation to diferent ladybird hosts. Our combined morphometric, molecular phylogenetic and ecological data provide support for a unifed species concept and an integrative taxonomy approach. What is a species? Tis is a perennial question in evolutionary biology. Te answer is complex and has been intensely argued for decades. Diferent species concepts corresponding to multiple biological properties pro- vide a means to recognize, delineate and describe species. Tese properties include diferences in morphological traits, nucleotide divergence and monophyly, reproductive isolation, ecological niches or adaptive zones, mate recognition or mating systems, geographic range, exclusive coalescence of alleles, etc. However, biologists from various research felds have advocated diferent and sometimes incompatible species concepts, leading to varying conclusions regarding delimitation of species and their numbers.
    [Show full text]