Differing Success of Defense Strategies in Two Parasitoid Wasps in Protecting Their Pupae Against a Secondary Hyperparasitoid
Harvey, J.A. ; Gols, R. ; Tanaka, T. - \ 2011
Annals of the Entomological Society Of America 104 (2011)5. - ISSN 0013-8746 - p. 1005 - 1011.
cotesia-glomerata l. - meteorus-pulchricornis - behavioral manipulation - separata lepidoptera - pseudaletia-separata - insect parasitoids - host caterpillars - life-history - braconidae - hymenoptera
During their larval development, endoparasitoids are known to dispose of host resources in several different ways. Some parasitoid wasps consume most or all tissues of the host, whereas others consume a small fraction of host resources and either ensure that the host moves away from the pupation site or allow the host to remain close to the parasitoid cocoon(s). Using a single host species, Mythimna separata Walker (Lepidoptera: Noctuidae), this study compares the success of the two pupation strategies in the solitary parasitoids Microplitis sp. and Meteorus pulchricornis Wesmael (Hymenoptera: Braconidae) against attack from a secondary hyperparasitoid, Gelis agilis F. (Hymenoptera: Ichneumonidae). The caudal appendages of M. separata caterpillars parasitized by Microplitis sp. remain physically attached to parasitoid cocoons and the caterpillars behave aggressively when disturbed. However, after Me. pulchricornis larvae emerge from caterpillars of their host, M. separata, the parasitoid larvae pupate in cocoons that are suspended by a single thick thread that hangs 1–2 cm from under a leaf. In choice tests conducted in petri dishes, significantly fewer cocoons of Microplitis sp. attended by caterpillars than unattended cocoons were hyperparasitized by G. agilis. By contrast, Me. pulchricornis cocoons that were hanging from corn, Zea mays L., plants were hyperparasitized as frequently as those which were attached to leaves. We discuss the potentially different selection pressures generated among natural enemies such as predators and hyperparasitoids in determining optimal pupal defense strategies in primary parasitoids.
The ‘usurpation hypothesis’ revisited: dying caterpillar repels attack from a hyperparasitoid wasp
Harvey, J.A. ; Tanaka, T. ; Kruidhof, M. ; Vet, L.E.M. ; Gols, R. - \ 2011
Animal Behaviour 81 (2011)6. - ISSN 0003-3472 - p. 1281 - 1287.
cotesia-glomerata l. - host behavior - developmental strategies - hymenoptera-braconidae - apanteles-melanoscelus - southwestern virginia - pseudaletia-separata - manipulation - parasitoids - lepidoptera
It has been posited that some parasitoid wasps ‘usurp’ their dying hosts as ‘bodyguards’ to protect the vulnerable parasitoid cocoons against attack from natural enemies such as predators or hyperparasitoids. Thus far, however, the hypothesis has been supported only in studies with insect predators. Two factors may account for this: first, hyperparasitoids, being more specialized than predators, are probably less easily rebuffed by the presence of an attending caterpillar; second, the host cocoon is used for reproduction by hyperparasitoids, but not by predators. We compared the survival of a solitary primary parasitoid, Microplitis sp., and successful parasitism by a secondary hyperparasitoid, Gelis agilis, from parasitoid cocoons with and without the presence of an ‘attending’ larva of the host, the armyworm, Mythimna separata. Mature Microplitis sp. larvae always emerge through the same host segment, leaving the posterior segments paralysed and attached to cocoons and the anterior segments freely moving. When disturbed by G. agilis females, M. separata larvae exhibited aggressive behaviour that repeatedly drove off approaching hyperparasitoids. In choice and no-choice experiments performed at 24 h intervals over 96 h, G. agilis successfully parasitized cocoons without attending caterpillars, but few cocoons with attending caterpillars were ever parasitized. Choice experiments, in which G. agilis wasps were released onto corn plants containing 24 h-old parasitoid cocoons with and without attending caterpillars, produced similar results. We provide the first experimental evidence that a solitary parasitoid usurps the behaviour of its host over several days as a ‘bodyguard’ against hyperparasitoids
Overall welfare assessment of laying hens: Comparing science-based, environmental-based and animal-based assessments
Shimmura, T. ; Bracke, M.B.M. ; Mol, R.M. de; Hirahara, S. ; Tanaka, T. - \ 2011
Animal Science journal 82 (2011)1. - ISSN 1344-3941 - p. 150 - 160.
decision-support system - burmese red junglefowl - large furnished cages - housing systems - domestic hens - feather pecking - battery cages - dustbathing behavior - rearing environment - physical condition
To increase the validity of evaluations and facilitate expansion and maintenance of assessment systems, we constructed a database of studies on the welfare of laying hens around the world. On the basis of this database, we devised a science-based welfare assessment model. Our model includes measurements, levels and weightings based on the scientific studies in the database, and can clarify the advantages and disadvantages of housing systems for laying hens from the viewpoint of the five freedoms. We also evaluated the usefulness of our model by comparing it with environment-based Animal Needs Index (ANI), another science-based model called FOWEL, and animal-based measurements. Our model showed that freedom from injury, pain and disease, and freedom from discomfort were more secure in the cage system, while non-cage systems scored better for natural behavior and freedom from fear and distress. A significant strong-positive correlation was found between the animal-based assessment and the total scores of ANI (rs = 0.94, P <0.05), FOWEL (rs = 0.99, P <0.05) or our model (rs = 0.99, P <0.05), which indicate that these different approaches to welfare assessment may be used almost interchangeably to ‘measure’ a common property (‘overall laying hen welfare’). However, assessments using our model and FOWEL were more sensitive than ANI and can be applied to cage systems, which suggest that our model and FOWEL may have added value.
Functional and evolutionary insights from the genomes of three parasitoid nasonia species
Werren, John H. ; Richards, Stephen ; Desjardins, Christopher A. ; Niehuis, Oliver ; Gadau, Jurgen ; Colbourne, John K. ; Beukeboom, Leo W. ; Desplan, Claude ; Elsik, Christine G. ; Grimmelikhuijzen, Cornelis J.P. ; Kitts, Paul ; Lynch, Jeremy A. ; Murphy, Terence ; Oliveira, Deodoro C.S.G. ; Smith, Christopher D. ; Zande, Louis De Van; Worley, Kim C. ; Zdobnov, Evgeny M. ; Aerts, Maarten ; Albert, Stefan ; Anaya, Victor H. ; Anzola, Juan M. ; Barchuk, Angel R. ; Behura, Susanta K. ; Bera, Agata N. ; Berenbaum, May R. ; Bertossa, Rinaldo C. ; Bitondi, Márcia M.G. ; Bordenstein, Seth R. ; Bork, Peer ; Bornberg-Bauer, Erich ; Brunain, Marleen ; Cazzamali, Giuseppe ; Chaboub, Lesley ; Chacko, Joseph ; Chavez, Dean ; Childers, Christopher P. ; Choi, Jeong Hyeon ; Clark, Michael E. ; Claudianos, Charles ; Clinton, Rochelle A. ; Cree, Andrew G. ; Cristino, Alexandre S. ; Dang, Phat M. ; Darby, Alistair C. ; Graaf, Dirk C. De; Devreese, Bart ; Dinh, Huyen H. ; Edwards, Rachel ; Elango, Navin ; Elhaik, Eran ; Ermolaeva, Olga ; Evans, Jay D. ; Foret, Sylvain ; Fowler, Gerald R. ; Gerlach, Daniel ; Gibson, Joshua D. ; Gilbert, Donald G. ; Graur, Dan ; Gründer, Stefan ; Hagen, Darren E. ; Han, Yi ; Hauser, Frank ; Hultmark, Da ; Hunter Iv, Henry C. ; Hurst, Gregory D.D. ; Jhangian, Shalini N. ; Jiang, Huaiyang ; Johnson, Reed M. ; Jones, Andrew K. ; Junier, Thomas ; Kadowaki, Tatsuhiko ; Kamping, Albert ; Kapustin, Yuri ; Kechavarzi, Bobak ; Kim, Jaebum ; Kim, Jay ; Kiryutin, Boris ; Koevoets, Tosca ; Kovar, Christie L. ; Kriventseva, Evgenia V. ; Kucharski, Robert ; Lee, Heewook ; Lee, Sandra L. ; Lees, Kristin ; Lewis, Lora R. ; Loehlin, David W. ; Logsdon, John M. ; Lopez, Jacqueline A. ; Lozado, Ryan J. ; Maglott, Donna ; Maleszka, Ryszard ; Mayampurath, Anoop ; Mazur, Danielle J. ; McClure, Marcella A. ; Moore, Andrew D. ; Morgan, Margaret B. ; Muller, Jean ; Munoz-Torres, Monica C. ; Muzny, Donna M. ; Nazareth, Lynne V. ; Neupert, Susanne ; Nguyen, Ngoc B. ; Nunes, Francis M.F. ; Oakeshott, John G. ; Okwuonu, Geoffrey O. ; Pannebakker, Bart A. ; Pejaver, Vikas R. ; Peng, Zuogang ; Pratt, Stephen C. ; Predel, Reinhard ; Pu, Ling Ling ; Ranson, Hilary ; Raychoudhury, Rhitoban ; Rechtsteiner, Andreas ; Reese, Justin T. ; Reid, Jeffrey G. ; Riddle, Megan ; Robertson, I.I.H.M. ; Romero-Severson, Jeanne ; Rosenberg, Miriam ; Sackton, Timothy B. ; Sattelle, David B. ; Schlüns, Helge ; Schmitt, Thomas ; Schneider, Martina ; Schüler, Andreas ; Schurko, Andrew M. ; Shuker, David M. ; Simões, Zila L.P. ; Sinha, Saurabh ; Smith, Zachary ; Solovyev, Victor ; Souvorov, Alexandre ; Springauf, Andreas ; Stafflinger, Elisabeth ; Stage, Deborah E. ; Stanke, Mario ; Tanaka, Yoshiaki ; Telschow, Arndt ; Vattathil, Carol Trent Selina ; Verhulst, I.I.E.C. ; Viljakainen, Lumi ; Wanner, Kevin W. ; Waterhouse, Robert M. ; Whitfield, James B. ; Wilkes, Timothy E. ; Williamson, Michael ; Willis, Judith H. ; Wolschin, Florian ; Wyder, Stefan ; Yamada, Takuji ; Yi, Soojin V. ; Zecher, Courtney N. ; Zhang, Lan ; Gibbs, Richard A. - \ 2010
Science 327 (2010)5963. - ISSN 0036-8075 - p. 343 - 348.
We report here genome sequences and comparative analyses of three closely related parasitoid wasps: Nasonia vitripennis, N. giraulti, and N. tongicomis. Parasitoids are important regulators of arthropod populations, including major agricultural pests and disease vectors, and Nasonia is an emerging genetic model, particularly for evolutionary and developmental genetics. Key findings include the identification of a functional DNA methylation tool kit; hymenopteran-spedfic genes including diverse venoms; lateral gene transfers among Pox viruses, Wolbachia, and Nasonia; and the rapid evolution of genes involved in nuclearmitochondrial interactions that are implicated in spedation. Newly developed genome resources advance Nasonia for genetic research, accelerate mapping and cloning of quantitative trait loci, and will ultimately provide tools and knowledge for further increasing the utility of parasitoids as pest insect-control agents.
Bioavailability of Xenobiotics in the Soil Environment
Katayama, A. ; Bhula, R. ; Burns, G.R. ; Carazo, E. ; Felsot, A. ; Hamilton, D. ; Harris, C. ; Kim, Y.H. ; Kleter, G.A. ; Koedel, W. ; Linders, J. ; Peijnenburg, J.G.M.W. ; Sabljic, A. ; Stephenson, R.G. ; Racke, D.K. ; Rubin, B. ; Tanaka, K. ; Unsworth, J. ; Wauchope, R.D. - \ 2010
In: Reviews of Environmental Contamination and Toxicology, Vol. 203 / Whitacre, D.M., New York : Springer - ISBN 9781441913517 - p. 1 - 86.
polycyclic aromatic-hydrocarbons - supercritical-fluid extraction - bound pesticide-residues - field-moist soils - artificially contaminated soils - persistent organic pollutants - earthworms eisenia-foetida - carbon-dioxide extraction - bacterial outer-membrane
When synthetic, xenobiotic compounds such as agrochemicals and industrial chemicals are utilized, they eventually reach the soil environment where they are subject to degradation, leaching, volatilization, sorption, and uptake by organisms. The simplest assumption is that such chemicals in soil are totally available to microorganisms, plant roots, and soil fauna via direct, contact exposure; subsequently these organisms are consumed as part of food web processes and bioaccumulation may occur, increasing exposures to higher organisms up the food chain. However, studies in the last two decades have revealed that chemical residues in the environment are not completely bioavailable, so that their uptake by biota is less than the total amount present in soil (Alexander 1995; Gevao et al. 2003; Paine et al. 1996). Therefore, the toxicity, biodegradability, and efficacy of xenobiotics are dependent on their soil bioavailability, rendering this concept profoundly important to chemical risk assessment and pesticide registration.
Electrostatic potentials of humic acid: Fluorescence quenching measurements and comparison with model calculations
Saito, T. ; Koopal, L.K. ; Nagasaki, S. ; Tanaka, S. - \ 2009
Colloids and Surfaces. A: Physicochemical and Engineering Aspects 347 (2009)1-3. - ISSN 0927-7757 - p. 27 - 32.
natural organic-matter - nica-donnan model - ion-binding - charge adjustments - proton binding - substances - adsorption - system - soft
Average electrostatic potentials of purified Aldrich humic acid (PAHA) are measured, based on quenching of the PAHA fluorescence by neutral and cationic quencher molecules with similar structures. The obtained negative potentials increased with increasing pH at a given salt concentration and weakly decreased with increasing salt concentration at given pH. The trends and the magnitudes of the potentials correspond with the few experimental results available in the literature. Comparison with potentials calculated by the electrostatic models from the charge of PAHA revealed that the average potentials obtained from the ion permeable sphere model and Donnan-EDL model agreed with the measured average potentials. With these two models it is assumed that a part of the PAHA charge is neutralized by the electrical double layer (EDL) around the PAHA particle in line with the view that humic acid is a nano-size particle partly permeable to small ions and solvent molecules. The potentials calculated by these two models are averages of the potential "inside" the particle (which governs the proton binding) and that in the EDL. The Donnan models, with both the fixed charges and the counter charges distributed over a volume that is greater than the particle volume itself, result in more negative potentials than the measured average potentials of PAHA. These observations suggest that the quenchers are located close to the functional groups but diffusely bound.
Multi-locus phylogeny of Pleosporales: a taxonomic, ecological and evolutionary re-evaluation
Zhang, Y. ; Schoch, C.L. ; Fournier, J. ; Crous, P.W. ; Gruyter, J. de; Woudenberg, J.H.C. ; Hirayama, K. ; Tanaka, K. ; Pointing, S.B. ; Spatafora, J.W. ; Hyde, K.D. - \ 2009
Studies in Mycology 64 (2009)1. - ISSN 0166-0616 - p. 85 - 102.
ribosomal dna-sequences - stagonospora-nodorum - molecular phylogeny - leptosphaeria-maculans - phaeosphaeria-nodorum - multigene phylogeny - multiple alignment - endophytic fungi - sp-nov - ascomycota
Five loci, nucSSU, nucLSU rDNA, TEF1, RPB1 and RPB2, are used for analysing 129 pleosporalean taxa representing 59 genera and 15 families in the current classification of Pleosporales. The suborder Pleosporineae is emended to include four families, viz. Didymellaceae, Leptosphaeriaceae, Phaeosphaeriaceae and Pleosporaceae. In addition, two new families are introduced, i.e. Amniculicolaceae and Lentitheciaceae. Pleomassariaceae is treated as a synonym of Melanommataceae, and new circumscriptions of Lophiostomataceae s. str, Massarinaceae and Lophiotrema are proposed. Familial positions of Entodesmium and Setomelanomma in Phaeosphaeriaceae, Neophaeosphaeria in Leptosphaeriaceae, Leptosphaerulina, Macroventuria and Platychora in Didymellaceae, Pleomassaria in Melanommataceae and Bimuria, Didymocrea, Karstenula and Paraphaeosphaeria in Montagnulaceae are clarified. Both ecological and morphological characters show varying degrees of phylogenetic significance. Pleosporales is most likely derived from a saprobic ancestor with fissitunicate asci containing conspicuous ocular chambers and apical rings. Nutritional shifts in Pleosporales likely occured from saprotrophic to hemibiotrophic or biotrophic.
A class-wide phylogenetic assessment of Dothideomycetes
Schoch, C.L. ; Crous, P.W. ; Groenewald, J.Z. ; Boehm, E.W.A. ; Burgess, T.I. ; Gruyter, J. de; Hoog, G.S. de; Dixon, L.J. ; Grube, M. ; Gueidan, C. ; Harada, Y. ; Hatakeyama, S. ; Hirayama, K. ; Hosoya, T. ; Huhndorf, S.M. ; Hyde, K.D. ; Jones, E.B.G. ; Kohlmeyer, J. ; Kruys, Å. ; Li, Y.M. ; Lücking, R. ; Lumbsch, H.T. ; Marvanová, L. ; Mbatchou, J.S. ; McVay, A.H. ; Miller, A.N. ; Mugambi, G.K. ; Muggia, L. ; Nelsen, M.P. ; Nelson, P. ; Owensby, C.A. ; Phillips, A.J.L. ; Phongpaichit, S. ; Pointing, S.B. ; Pujade-Renaud, V. ; Raja, H.A. ; Rivas Plata, E. ; Robbertse, B. ; Ruibal, C. ; Sakayaroj, J. ; Sano, T. ; Selbmann, L. ; Shearer, C.A. ; Shirouzu, T. ; Slippers, B. ; Suetrong, S. ; Tanaka, K. ; Volkmann-Kohlmeyer, B. ; Wingfield, M.J. ; Wood, A.R. ; Woudenberg, J.H.C. ; Yonezawa, H. ; Zhang, Y. ; Spatafora, J.W. - \ 2009
Studies in Mycology 64 (2009)1. - ISSN 0166-0616 - p. 1 - 15.
ribosomal dna-sequences - multigene phylogenies - molecular phylogeny - maximum-likelihood - multiple alignment - marine ascomycota - rdna sequences - fungi - evolution - classification
We present a comprehensive phylogeny derived from 5 genes, nucSSU, nucLSU rDNA, TEF1, RPB1 and RPB2, for 356 isolates and 41 families (six newly described in this volume) in Dothideomycetes. All currently accepted orders in the class are represented for the first time in addition to numerous previously unplaced lineages. Subclass Pleosporomycetidae is expanded to include the aquatic order Jahnulales. An ancestral reconstruction of basic nutritional modes supports numerous transitions from saprobic life histories to plant associated and lichenised modes and a transition from terrestrial to aquatic habitats are confirmed. Finally, a genomic comparison of 6 dothideomycete genomes with other fungi finds a high level of unique protein associated with the class, supporting its delineation as a separate taxon
Adsorption of heterogeneously charged nanoparticles on a variably charged surface by the extended surface complexation approach: Charge regulation, chemical heterogeneity, and surface complexation
Saito, T. ; Koopal, L.K. ; Nagasaki, S. ; Tanaka, S. - \ 2008
The Journal of Physical Chemistry Part B: Condensed Matter, Materials, Surfaces, Interfaces & Biophysical 112 (2008)5. - ISSN 1520-6106 - p. 1339 - 1349.
spherical colloidal particles - double-layer interaction - electrical double-layer - electrostatic free-energy - poisson-boltzmann theory - natural organic-matter - humic substances - polyelectrolyte adsorption - protein adsorption - ion-binding
Adsorption of randomly branched polyelectrolytes, hairy particles and internally structured macromolecules, collectively denoted as heterogeneously charged nanoparticles, on charged surfaces is important in. many technological and natural processes. In this paper, we will focus on (1) the charge regulation of both the nanoparticle and the surface and (2) the surface complexation between the particle functional groups and the surface sites and will theoretically study the adsorption using the extended surface complexation approach. The model explicitly considers the electrochemical potential of a nanoparticle with an average (smeared-out) structure and charge both in bulk solution and on the surface to obtain the equilibrium adsorption. The chemical heterogeneity of the particle is described by a distribution of the protonation constant. Detailed analysis of the chemical potential of the adsorbed nanoparticle reveals that the pH and salt dependence of the adsorption can be largely explained by the balance between an energy gain resulting from the particle and surface charge regulation and the surface complexation and an energy loss from the unfavorable interparticle electrostatic repulsion close to the surface. This conclusion is also supported by the strong impacts that the chemical heterogeneity of the particle functional groups, the magnitude of the surface complexation, the number of the functional groups, and the size of the particle have on the adsorption.
Interannual variation of water balance and summer evapotranspiration in an eastern Siberian larch forest over a 7-year period (1998-2006)
Ohta, T. ; Maximov, T.C. ; Dolman, A.J. ; Nakai, T. ; Molen, M.K. van der; Kononov, A.V. ; Maximov, T. ; Hiyama, T. ; Iijima, Y. ; Moors, E.J. ; Tanaka, H. - \ 2008
Agricultural and Forest Meteorology 148 (2008)12. - ISSN 0168-1923 - p. 1941 - 1953.
surface-energy balance - boreal aspen forest - long-term - vegetation - exchange - fluxes - carbon - transpiration - conductance - closure
Water vapor, energy fluxes, and environmental conditions were measured in an eastern Siberian larch forest for 7 water years, from 1998 to 2006, to understand the water-balance characteristics and interannual variation (IAV). The latent heat flux accounted for 38¿67% of the sum of turbulent heat fluxes in June, July, and August, a relatively moderate fraction was compared to values measured at mid- and low latitudes. More than 70% of the annual precipitation evaporated during May to September. Annual evapotranspiration, including interception loss, was relatively steady at 169¿220 mm compared with the wide range in annual precipitation (111¿347 mm year¿1). The evapotranspiration rate was 1.49¿2.30 mm day¿1 on a daily basis from May to September above a dry canopy. This feature is one of the remarkable characteristics of the water balance in eastern Siberian forests. The thawing depth of the permafrost has been rapidly deepening since 2004, such that the maximal thawing depth varied from 127 cm before 2003 to over 200 cm after 2004. At the same time, there was a very large increase in the moisture content of the surface soil. This increase could not be explained by the amount of annual precipitation alone and may have been due to inflow from the deeper thawing layer. The IAV of evapotranspiration was small, but the yearly evapotranspiration coefficient (the ratio of evapotranspiration to potential evaporation) ranged from 0.30 to 0.45. These results indicate that the IAV of evapotranspiration is controlled by regulation of the land surface rather than by atmospheric demand. Soil-moisture content was the most important variable among the factors determining the evapotranspiration coefficient at an interannual temporal scale. This result differs somewhat from previous satellite-based findings that air temperature was a major variable for plant activity. This difference might result from the fact that the IAV of soil water content did not correspond to that of the precipitation amount because of the presence of the permafrost. By contrast, the soil water content was strongly affected by precipitation in the previous summer.
Comparing the physiological effects and function of larval feeding in closely-related endoparasitoids (Braconidae: Microgastrinae)
Harvey, J.A. ; Bezemer, T.M. ; Gols, R. ; Nakamatsu, Y. ; Tanaka, T. - \ 2008
Physiological Entomology 33 (2008)3. - ISSN 0307-6962 - p. 217 - 225.
wasp cotesia-congregata - hornworm manduca-sexta - 4 trophic levels - tobacco hornworm - parasitic wasp - developmental strategies - insect parasitoids - host behavior - growth - hymenoptera
The larvae of most endoparasitoid wasps consume virtually all host tissues before pupation. However, in some clades, the parasitoid larvae primarily consume haemolymph and fat body and emerge through the side of the host, which remains alive and active for up to several days. The evolutionary significance of this host-usage strategy has attracted attention in recent years. Recent empirical studies suggest that the surviving larva guards the parasitoid broods against natural enemies such as predators and hyperparasitoids. Known as the 'usurpation hypothesis', the surviving larvae bite, regurgitate fluids from the gut, and thrash the head capsule when disturbed. In the present study, the 'usurpation hypothesis' is tested in the association involving Manduca sexta, its parasitoid Cotesia congregata, and a secondary hyperparasitoid Lysibia nana. Percentage parasitoid survival is higher and hyperparasitism lower when cocoons of C. congregata are attached to the dorsum of M. sexta caterpillars. Fat body contents in several associations involving solitary and gregarious parasitoids feeding on haemolymph and fat body are also compared. The amount of fat body retained in parasitized caterpillars varies considerably from one association to another. In M. sexta and Pieris brassicae, considerable amounts of fat body remain after parasitoid emergence whereas, in Cotesia kariyai and Cotesia rufricus, virtually all of the fat body is consumed by the parsasitoid larvae. The length of post-egression survival of parasitized caterpillars differs considerably in several tested associations. In Pseudeletia separata, most larvae die within a few hours of parasitoid emergence whereas, in M. sexta, parasitized larvae live up to 2 weeks after parasitoid emergence. Larvae in other associations parasitized by gregarious and solitary endoparasitoids live for intermediate periods. The results are discussed in relation to the adaptive significance of different feeding strategies of immature parasitoids and of the costs and benefits of retaining the parasitized caterpillar in close proximity with the parasitoid cocoons
Do Parasitized caterpillars protect their parasitoids from hyperparasitoids? A test of the 'usurpation hypothesis'
Harvey, J.A. ; Kos, M. ; Nakamatsu, Y. ; Tanaka, T. ; Dicke, M. ; Vet, L.E.M. ; Brodeur, J. ; Bezemer, T.M. - \ 2008
Animal Behaviour 76 (2008)3. - ISSN 0003-3472 - p. 701 - 708.
host behavior - insect parasitoids - wasp - manipulation - braconidae - predation - selection - quality - snail - larva
Caterpillars that are attacked by some species of parasitoid wasps are known to survive for several days after the parasitoid larvae emerge and pupate. It has been argued that the behaviour of the parasitized larva is `usurped¿ by the parasitoid and that it `guards¿ the parasitoid cocoons against their own natural enemies such as hyperparasitoids (the `usurpation hypothesis'). We tested this hypothesis in the association involving a gregarious endoparasitoid, the wasp Cotesia glomerata; caterpillars of its host, the large cabbage white butterfly Pieris brassicae; and a pupal hyperparasitoid, the wasp Lysibia nana. In laboratory experiments, we presented cocoon broods of C. glomerata to single females of L. nana in arenas for 6 h. We tested several treatments for rates of primary parasitoid survival, including variation in the position of the caterpillar and the presence or absence of an additional silk web spun by parasitized caterpillars. Parasitized P. brassicae larvae survived longer than the period necessary for C. glomerata adults to emerge. Rates of parasitoid survival were, however, unaffected by the presence of a P. brassicae larva on the cocoon brood, although significantly more parasitoids emerged when the silk web was present. Analyses of the foraging behaviour of individual L. nana females in arenas, performed using Observer software, revealed that the wasps showed a greater tendency to leave cocoons when caterpillars and silk were present. The laboratory experiments only partially support the usurpation hypothesis. In nature, usurpation of the host of the primary parasitoid may be a more effective strategy against generalist predators than against more specialized and better-adapted hyperparasitoids
Trends in Pesticide Use on Transgenic versus Conventional Crops
Kleter, G.A. ; Bhula, R. ; Bodnaruk, K. ; Carazo, E. ; Felsot, A.S. ; Harris, C.A. ; Katayama, A. ; Kuiper, H.A. ; Racke, K.D. ; Rubin, B. ; Shevah, Y. ; Stephenson, G.R. ; Tanaka, K. ; Unsworth, J. ; Wauchope, R.D. ; Wong, S.S. - \ 2008
ISB News Report 2008 (2008)8. - p. 5 - 8.
Altered pesticide use on transgenic crops and the associated general impact from an environmental perspective
Kleter, G.A. ; Bhula, R. ; Bodnaruk, K. ; Carazo, E. ; Felsot, A.S. ; Harris, C.A. ; Katayama, A. ; Kuiper, H.A. ; Racke, K.D. ; Rubin, B. ; Shevah, Y. ; Stephenson, G.R. ; Tanaka, K. ; Unsworth, J. ; Wauchope, R.D. ; Wong, S.S. - \ 2007
Pest Management Science 63 (2007)11. - ISSN 1526-498X - p. 1107 - 1115.
farm-level - cotton - india
The large-scale commercial cultivation of transgenic crops has undergone a steady increase since their introduction 10 years ago. Most of these crops bear introduced traits that are of agronomic importance, such as herbicide or insect resistance. These traits are likely to impact upon the use of pesticides on these crops, as well as the pesticide market as a whole. Organizations like USDA-ERS and NCFAP monitor the changes in crop pest management associated with the adoption of transgenic crops. As part of an IUPAC project on this topic, recent data are reviewed regarding the alterations in pesticide use that have been observed in practice. Most results indicate a decrease in the amounts of active ingredients applied to transgenic crops compared with conventional crops. In addition, a generic environmental indicator - the environmental impact quotient (EIQ) - has been applied by these authors and others to estimate the environmental consequences of the altered pesticide use on transgenic crops. The results show that the predicted environmental impact decreases in transgenic crops. With the advent of new types of agronomic trait and crops that have been genetically modified, it is useful to take also their potential environmental impacts into account.
Analysis of copper binding in the ternary system Cu2+/Humic Acid/Goethite at neutral to acidic pH
Saito, T. ; Koopal, L.K. ; Nagasaki, S. ; Tanaka, S. - \ 2005
Environmental Science and Technology 39 (2005)13. - ISSN 0013-936X - p. 4886 - 4893.
metal-ion binding - adsorbed humic substances - natural organic-matter - competitive adsorption - exchange properties - charge adjustments - exafs spectroscopy - fulvic-acid - goethite - model
Binding of heavy metal and actinide ions to natural colloids, such as humic substances (HSs) and metal (hydr)oxides, plays an important role in the ecotoxicological behavior of these ions. Several thermodynamic models have been constructed to predict the speciation of these ions in metal/HS or metal/oxide binary systems. However, in natural environments the adsorption of HSs on oxides can influence the binding of target metals, leading to deviation from the additivity of calibrated binary models. In this study binding of copper (Cu 2+) to the purified Aldrich humic acid (PAHA)/goethite complex in the neutral to acidic pH region was investigated by measuring Cu2+ binding isotherms. The measured isotherms were compared with the results obtained for the binary systems under similar conditions. The comparison revealed that Cu2+ binding in the ternary system is enhanced with respect to the sum of Cu2+ binding in the corresponding binary systems. From the analysis of the charging behavior of the adsorbed PAHA as well as the smeared-out potential profile near the PAHA/goethite interface, the increase of Cu2+ binding to the complex was mainly attributed to the decrease of proton competition to the functional groups of the adsorbed PAHA and the change of the electrostatic potential in the vicinity of the goethite surface
|The effect of the cultivation of genetically modified crops on the use of pesticides and the impact thereof on the environment
Kleter, G.A. ; Bhula, R. ; Bodnaruk, K. ; Carazo, E. ; Felsot, A.S. ; Harris, C.A. ; Katayama, A. ; Kuiper, H.A. ; Racke, K. ; Rubin, B. ; Shevah, Y. ; Stephenson, G.R. ; Tanaka, K. ; Unsworth, J. ; Wong, S.S. - \ 2005
In: International workshop on crop protection chemistry in Latin America : harmonized approaches for environmental assessment and regulation 14 - 17 February, 2005, San Jose, Costa Rica Oxford : IUPAC - p. 49 - 76.
Electrostatic interaction models for ion binding to humic substances
Saito, T. ; Nagasaki, S. ; Tanaka, S. ; Koopal, L.K. - \ 2005
Colloids and Surfaces. A: Physicochemical and Engineering Aspects 265 (2005)1-3. - ISSN 0927-7757 - p. 104 - 113.
proton binding - chemical-composition - molecular-size - acids - parameters - adsorption - matter
Preferably, the description of ion binding to humic substances (HSs) is done with thermodynamic constants that do not depend on the environmental conditions. To solve this problem, models have to be made that describe the electrostatic and specific interactions. With a given electrostatic model the charge/pH curves of HS at different salt levels can be re-plotted as a function of the local pH near the sites (pHloc) of HSs. If the model is appropriate, the charge/pHloc curves will merge into a master curve (MC). In this study five electrostatic models were investigated to obtain pHloc for purified Aldrich humic acid (PAHA): rigid sphere (RS), ion-permeable sphere, Donnan (NICA), Donnan-EV, and Donnan-EDL. The RS model is tested in two versions; one based on the measured hydrodynamic radius (RS-a h) and the other on an optimized radius (RS-aopt). The ion-permeable sphere model uses the hydrodynamic radius and provides the potential distribution; as characteristic potential the radial average inside the sphere is used. In the Donnan (NICA) model the volume of the sphere, V D, in which the charge of PAHA is neutralized, is optimized with a constraint between VD and ionic strength, and in the Donnan-EV model VD is calculated by setting the radius of the gel as the sum of the hydrodynamic radius of PAHA and the Debye length. The Donnan-EDL model uses the hydrodynamic particle radius and is based on a combination of the Donnan model and the diffuse electrical double layer model. Only the RS-aopt, Donnan (NICA), and Donnan-EV models give adequate MCs. The positions of the MCs differ with respect to each other. This means that the discrimination between electrostatic and intrinsic interactions is model-dependent and therefore arbitrary. The Donnan (NICA) model has a practical advantage over the other two models because this model needs no measurements of the size of HS. For the purpose of the routine fitting of ion-binding data to an ion-binding isotherm equation that includes the electrostatics, this advantage is quite important
Application of the NICADonnan model for proton, copper and uranyl binding to humic acid
Saito, T. ; Nagasaki, S. ; Tanaka, S. ; Koopal, L.K. - \ 2004
Radiochimica Acta 92 (2004)9-11. - ISSN 0033-8230 - p. 567 - 574.
metal-ion binding - fulvic-acids - humate interactions - substances - complexation - adsorption - parameters - heterogeneity - uranium(vi) - goethite
Humic acids are natural organic materials that play an important role in the migration of heavy metal and actinide ions in aquatic and soil systems. In the present study, the binding of protons, copper ions and uranyl ions to the purified Aldrich humic acid (PAHA) is investigated and the results are modeled with the Non-Ideal Competitive Adsorption (NICA) model extended with electrostatic interactions according to the Donnan model (NICA-Donnan model). The NICA part of the model enables one to describe the competitive ion binding to a heterogeneous substrate taking into account a different stoichiometry per ion. The NICA-Donnan model can describe the binding of the ions to PAHA in large concentration ranges (3
Adsorption of humic acid on goethite: Isotherms, charge adjustments and potential profiles
Saito, T. ; Koopal, L.K. ; Riemsdijk, W.H. van; Nagasaki, S. ; Tanaka, S. - \ 2004
Langmuir 20 (2004)3. - ISSN 0743-7463 - p. 689 - 700.
natural organic-matter - oxide-water interface - metal-ion binding - donnan model parameters - fulvic-acid - iron-oxide - polyelectrolyte adsorption - weak polyelectrolytes - humate interactions - surface ionization
The adsorption of natural organic matter (NOM) on mineral (hydr)oxide plays an important role in the evaluation of the speciation of toxic metal ions in the environment. Because both NOM and mineral oxide have variable charges that adjust upon adsorption, a good understanding of proton binding is required before the binding of metal ions can be understood. In this study, the adsorption of purified Aldrich humic acid (PAHA) on goethite was examined as a function of the environmental conditions (pH, salt concentration, and free concentration of PAHA) together with the proton adsorption to PAHA, goethite, and their mixtures. The induced charges on both components were separated on the basis of the difference between the charge/pH curves of the mixture and those of the single components. The electrostatic potential profile across the adsorbed layer was obtained as a numerical solution of the Poisson-Boltzmann equation using the charge density of the adsorbed PAHA and the goethite surface. From the quantitative evaluation of the induced charge on both components, it is revealed that the degree of the charge adjustment is related to the electrostatic affinity between the PAHA segments and the goethite surface, the electrostatic repulsion between the PAHA segments, and the electrostatic shielding by salt ions. Considering the charge distribution of the adsorbed PAHA at the goethite surface, it is concluded that the change of the charge adjustment is sensitive to that of the conformation of the adsorbed PAHA. From the detailed inspection of the assumptions made and the comparison with the reported theoretical calculations, the obtained potential profiles are considered to broadly reflect the true potential profiles. Because a charge adjustment is not frequently considered in detail in relation to the NOM adsorption on metal (hydr)oxides, the obtained results can form the basis for the further development of modeling of the adsorption of NOM on (hydr)oxide surfaces.
Monolithic silica-based capillary reversed-phase liquid chromatography/electrospray mass spectrometry for plant metabolomics
Tolstikov, V.V. ; Lommen, A. ; Nakanishi, K. ; Tanaka, N. ; Fiehn, O. - \ 2003
Analytical Chemistry 75 (2003)23. - ISSN 0003-2700 - p. 6737 - 6740.
functional genomics - polar compounds - ionization - columns - identification - validation - efficiency - flavonoids
Application of C18 monolithic silica capillary columns in HPLC coupled to ion trap mass spectrometry detection was studied for probing the metabolome of the model plant Arabidopsis thaliana. It could be shown that the use of a long capillary column is an easy and effective approach to reduce ionization suppression by enhanced chromatographic resolution. Several hundred peaks could be detected using a 90-cm capillary column for LC separation and a noise reduction and automatic peak alignment software, which outperformed manual inspection or commercially available mass spectral deconvolution software.