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Sample records for attenuata sipk wipk

  1. MAPK-dependent JA and SA signalling in Nicotiana attenuata affects plant growth and fitness during competition with conspecifics

    Directory of Open Access Journals (Sweden)

    Meldau Stefan

    2012-11-01

    Full Text Available Abstract Background Induced defense responses to herbivores are generally believed to have evolved as cost-saving strategies that defer the fitness costs of defense metabolism until these defenses are needed. The fitness costs of jasmonate (JA-mediated defenses have been well documented. Those of the early signaling units mediating induced resistance to herbivores have yet to be examined. Early signaling components that mediate herbivore-induced defense responses in Nicotiana attenuata, have been well characterized and here we examine their growth and fitness costs during competition with conspecifics. Two mitogen-activated protein kinases (MAPKs, salicylic acid (SA-induced protein kinase (SIPK and wound-induced protein kinase (WIPK are rapidly activated after perception of herbivory and both kinases regulate herbivory-induced JA levels and JA-mediated defense metabolite accumulations. Since JA-induced defenses result in resource-based trade-offs that compromise plant productivity, we evaluated if silencing SIPK (irSIPK and WIPK (irWIPK benefits the growth and fitness of plants competiting with wild type (WT plants, as has been shown for plants silenced in JA-signaling by the reduction of Lipoxygenase 3 (LOX3 levels. Results As expected, irWIPK and LOX3-silenced plants out-performed their competing WT plants. Surprisingly, irSIPK plants, which have the largest reductions in JA signaling, did not. Phytohormone profiling of leaves revealed that irSIPK plants accumulated higher levels of SA compared to WT. To test the hypothesis that these high levels of SA, and their presumed associated fitness costs of pathogen associated defenses in irSIPK plants had nullified the JA-deficiency-mediated growth benefits in these plants, we genetically reduced SA levels in irSIPK plants. Reducing SA levels partially recovered the biomass and fitness deficits of irSIPK plants. We also evaluated whether the increased fitness of plants with reduced SA or JA levels

  2. MAPK-dependent JA and SA signalling in Nicotiana attenuata affects plant growth and fitness during competition with conspecifics

    Science.gov (United States)

    2012-01-01

    Background Induced defense responses to herbivores are generally believed to have evolved as cost-saving strategies that defer the fitness costs of defense metabolism until these defenses are needed. The fitness costs of jasmonate (JA)-mediated defenses have been well documented. Those of the early signaling units mediating induced resistance to herbivores have yet to be examined. Early signaling components that mediate herbivore-induced defense responses in Nicotiana attenuata, have been well characterized and here we examine their growth and fitness costs during competition with conspecifics. Two mitogen-activated protein kinases (MAPKs), salicylic acid (SA)-induced protein kinase (SIPK) and wound-induced protein kinase (WIPK) are rapidly activated after perception of herbivory and both kinases regulate herbivory-induced JA levels and JA-mediated defense metabolite accumulations. Since JA-induced defenses result in resource-based trade-offs that compromise plant productivity, we evaluated if silencing SIPK (irSIPK) and WIPK (irWIPK) benefits the growth and fitness of plants competiting with wild type (WT) plants, as has been shown for plants silenced in JA-signaling by the reduction of Lipoxygenase 3 (LOX3) levels. Results As expected, irWIPK and LOX3-silenced plants out-performed their competing WT plants. Surprisingly, irSIPK plants, which have the largest reductions in JA signaling, did not. Phytohormone profiling of leaves revealed that irSIPK plants accumulated higher levels of SA compared to WT. To test the hypothesis that these high levels of SA, and their presumed associated fitness costs of pathogen associated defenses in irSIPK plants had nullified the JA-deficiency-mediated growth benefits in these plants, we genetically reduced SA levels in irSIPK plants. Reducing SA levels partially recovered the biomass and fitness deficits of irSIPK plants. We also evaluated whether the increased fitness of plants with reduced SA or JA levels resulted from

  3. Up-regulation of MPK4 increases the feeding efficiency of the green peach aphid under elevated CO2 in Nicotiana attenuata.

    Science.gov (United States)

    Guo, Huijuan; Peng, Xinhong; Gu, Liyuan; Wu, Jianqiang; Ge, Feng; Sun, Yucheng

    2017-12-16

    Previous research has shown that elevated CO2 reduces plant resistance against insects and enhances the water use efficiency of C3 plants, which improves the feeding efficiency of aphids. Although plant mitogen-activated protein kinases (MAPKs) are known to regulate water relations and phytohormone-mediated resistance, little is known about the effect of elevated CO2 on MAPKs and the cascading effects on aphids. By using stably transformed Nicotiana attenuata plants silenced in MPK4, wound-induced protein kinase (WIPK), or salicylic acid-induced protein kinase (SIPK), we determined the functions of MAPKs in plant-aphid interactions and their responses to elevated CO2. The results showed that among all plant genotypes, inverted repeat MPK4 plants had the largest stomatal apertures, the lowest water content, the strongest jasmonic acid (JA)-dependent resistance, and the lowest aphid numbers, suggesting that MPK4 affects plant responses to aphids by regulating stomatal aperture and JA-dependent resistance. Regardless of aphid infestation, elevated CO2 up-regulated MPK4, but not WIPK or SIPK, in wild-type plants. Elevated CO2 increased the number, mean relative growth rate, and feeding efficiency of aphids on all plant genotypes except inverted repeat MPK4. We conclude that MPK4 is a CO2-responsive plant determinant that regulates the molecular interaction between plants and aphids. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  4. Iridoid constituents of Tarenna attenuata.

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    Yang, Xian-Wen; Ma, Yan-Ling; He, Hong-Ping; Wang, Yue-Hu; Di, Ying-Tong; Zhou, Hua; Li, Ling; Hao, Xiao-Jiang

    2006-06-01

    Members of a rare type of iridoid with two alpha,beta-unsaturated acid units were isolated from the whole plant of Tarenna attenuata, including a new compound, tarennin (1), an extraction artifact, and seven new glucosides, tarenninosides A-G (2-8), together with two known iridoid glucosides, ixoside and 10-methylixoside. The structures of 1-8 were elucidated by analysis of spectroscopic data including HMQC, HMBC, 1H-1H COSY, and ROESY NMR spectra and by comparison with known analogues. Antioxidant and cytotoxic activities were evaluated for these 10 compounds, but none showed positive activity.

  5. Mixed lignan-neolignans from Tarenna attenuata.

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    Yang, Xian-Wen; Zhao, Pei-Ji; Ma, Yan-Lin; Xiao, Hai-Tao; Zuo, Yi-Qing; He, Hong-Ping; Li, Ling; Hao, Xiao-Jiang

    2007-04-01

    Six new mixed lignan-neolignans and 20 known compounds were isolated from the whole plant of Tarenna attenuata. By analysis of physical and spectroscopic data, the structures of the new compounds were elucidated as (1R,5R,6R)-6-{4-O-[2-(1-(4-hydroxy-3-methoxyphenyl))glycerol]-3,5-dimethoxyphenyl}-3,7-dioxabicyclo[3.3.0]octan-2-one (1), 5' '-methoxyhedyotisol A (2), 4' '-O-(8-guaiacylglycerol)buddlenol A (3), 5' '-methoxy-4' '-O-(8-guaiacylglycerol)buddlenol A (4), 4,6-dimethoxy-5-hydroxy-3-hydroxymethyl-2-(3,4,5-trimethoxyphenyl)-2,3-dihydrobenzofuran (5), and 7-O-ethylguaiacylglycerol (6). Compounds 1, 5, 6, and 8 showed potent antioxidant activities against H2O2-induced impairment in PC12 cells, and compounds 1, 2, 5, and 7 scavenged DPPH radical strongly with IC50 values of 72, 87, 45, and 55 microM, respectively.

  6. Phytochemical and Biological Studies of Agave attenuata

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    Rizwan, Komal; Zubair, Muhammad; Rasool, Nasir; Riaz, Muhammad; Zia-Ul-Haq, Muhammad; de Feo, Vincenzo

    2012-01-01

    The present study was conducted to examine various biological activities of a methanol extract of Agave attenuata leaves. GC-MS analysis of the n-hexane fraction from the extract revealed the presence of 31 compounds, with mono-2-ethylhexyl phthalate (11.37%), 1,2-benzenedicarboxylic acid (6.33%), n-docosane (6.30%) and eicosane (6.02%) as the major components. The leaves contained appreciable levels of total phenolic contents (10.541–39.35 GAE, mg/100 g) and total flavonoid contents (43.35–304.8 CE, mg/100 g). The extract and some of its fractions showed moderate antimicrobial effects. Leaves extract and fractions also exhibited a good antioxidant potential when measured by DPPH radical scavenging activity and inhibition of lipid peroxidation assays. The hemolytic effect of the plant was found to be in a range of 1.01%–2.64%. From the present study it is concluded that this plant could be used as a source of natural antioxidants and functional food nutraceutical applications. PMID:22754375

  7. Description of the male sex of HElota attenuata Rits

    NARCIS (Netherlands)

    Ritsema Cz., C.

    1913-01-01

    Helota attenuata belongs, together with Dureli, Moutoni and Helleri, to the group of Helota rotundata (see my „Synopsis” in Notes Leyd. Mus. Vol. XIII, p. 227). It is easily recognizable among these species by the coarse punctuation on the pronotum and by the reddish testaceous colour of the elytral

  8. Multiple interactions of NaHER1 protein with abscisic acid signaling in Nicotiana attenuata plants

    OpenAIRE

    Dinh, Son Truong; Baldwin, Ian T; Gális, Ivan

    2013-01-01

    Previously, we identified a novel herbivore elicitor-regulated protein in Nicotiana attenuata (NaHER1) that is required to suppress abscisic acid (ABA) catabolism during herbivore attack and activate a full defense response against herbivores. ABA, in addition to its newly defined role in defense activation, mainly controls seed germination and stomatal function of land plants. Here we show that N. attenuata seeds silenced in the expression of NaHER1 by RNA interference (irHER1) accumulated l...

  9. Tarennane and tarennone, two novel chalcone constituents from Tarenna attenuata.

    Science.gov (United States)

    Yang, Xian-Wen; Wang, Jun-Song; Wang, Yue-Hu; Xiao, Hai-Tao; Hu, Xu-Jia; Mu, Shu-Zhen; Ma, Yan-Lin; Lin, Hua; He, Hong-Ping; Li, Ling; Hao, Xiao-Jiang

    2007-05-01

    Two novel chalcone constituents, tarennane (1) and tarennone (2), together with nine known compounds, were isolated from the whole plant of Tarenna attenuata. By analysis of physical and spectroscopic data, the structures of new compounds were elucidated as (E)-4-[3-(4-hydroxy-3-methoxyphenyl)-acryl]-3,4,5-trimethoxycyclohexa-2,5-dienone (1) and 1,2-bis(3,5-dimethoxy-4-hydroxyphenyl)-3-hydroxypropan-1-one (2). These two compounds were tested for antioxidant activities in the MTT and DPPH assays. Compound 1 revealed potent antioxidant activities against H2O2-induced impairment in PC12 cells, but neither of them showed DPPH radical-scavenging activity with IC50 values of 181.1 and 210.3 microM, respectively.

  10. Effects of pesticide formulations and active ingredients on the coelenterate Hydra attenuata (Pallas, 1766).

    Science.gov (United States)

    Demetrio, Pablo M; Bulus Rossini, Gustavo D; Bonetto, Carlos A; Ronco, Alicia E

    2012-01-01

    Lethal effects of active ingredients and formulations of widely used soybean pesticides were assessed with the Hydra attenuata toxicity test. Studied pesticides were insecticides chlorpyrifos and cypermethrin, and herbicide glyphosate. Results indicate the following toxicity trend: chlorpyrifos > cypermethrin > glyphosate. Tested active ingredients of insecticides and respective formulations did not significantly differ between them. Glyphosate formulation exhibited higher toxicity at low concentrations (LC(1-10)) respect to active ingredient, reversing this behavior at higher concentrations (LC(50-90)). Comparing H. attenuata sensitivity with existent toxicity data for aquatic organisms indicates that this species is poorly sensitive to tested insecticides and highly sensitive to the herbicide.

  11. Ecological costs and benefits correlated with trypsin protease inhibitor production in Nicotiana attenuata

    NARCIS (Netherlands)

    Glawe, G.A.; Zavala, J.A.; Kessler, A.; Van Dam, N.M.; Baldwin, I.T.

    2003-01-01

    Genotypes of the wild tobacco Nicotiana attenuata from different geographic regions in North America vary considerably in the level of constitutive and inducible trypsin protease inhibitors (TrypPIs), a potent direct defense, as well as in the production of herbivore-induced volatiles that function

  12. Nicotiana benthamiana MAPK-WRKY pathway confers resistance to a necrotrophic pathogen Botrytis cinerea.

    Science.gov (United States)

    Adachi, Hiroaki; Ishihama, Nobuaki; Nakano, Takaaki; Yoshioka, Miki; Yoshioka, Hirofumi

    2016-06-02

    MEK2-SIPK/WIPK cascade, a Nicotiana benthamiana mitogen-activated protein kinase (MAPK) cascade, is an essential signaling pathway for plant immunity and involved in hypersensitive response (HR) accompanied by cell death. WRKY transcription factors as substrates of SIPK and WIPK have been isolated and implicated in HR cell death. Here, we show virus-induced gene silencing of WRKY genes compromised constitutively active MEK2-triggered cell death in N. benthamiana leaves. In general, HR cell death enhances susceptibility to necrotrophic pathogens such as Botrytis cinerea. However, the WRKY gene silencing elevated susceptibility to B. cinerea. These findings suggest that downstream WRKYs of MEK2-SIPK/WIPK cascade are required for cell death-dependent and -independent immunities in N. benthamiana.

  13. [Sighting of Stenella attenuata, the spotted dolphin, in Culebra Bay, Costa Rica, 1999-2000].

    Science.gov (United States)

    Rodríguez Sáenz, Karina; Rodríguez-Fonseca, Javier

    2004-12-01

    Parallel to a zooplankton study (1999-2000) observations were made (from an inflatable boat), on the presence of dolphins along a transect (-8 km long) on the axis of Culebra Bay (24 km2), Gulf of Papagayo, Pacific coast of Costa Rica. Dolphins were found during 20 of the 31 boat surveys conducted. The only species of cetacean found in the bay was Stenella attenuata, the spotted dolphin. These sightings were more frequent during the rainy season, particularly during the month of May of both years. The presence of S. attenuata in Culebra Bay might be associated to the abundances of fish and mollusks (their presumed prey: for example, squids), as evidenced by fishery statistics available for this zone of the Pacific coast of Costa Rica.

  14. Changes in cytokinins are sufficient to alter developmental patterns of defense metabolites in Nicotiana attenuata

    Czech Academy of Sciences Publication Activity Database

    Bruetting, C.; Schaefer, N.; Vaňková, Radomíra; Gase, K.; Baldwin, I.T.; Meldau, S.

    2017-01-01

    Roč. 89, č. 1 (2017), s. 15-30 ISSN 0960-7412 R&D Projects: GA MŠk LD14120 Institutional support: RVO:61389030 Keywords : proteinase-inhibitor production * plant defense * arabidopsis-thaliana * leaf senescence * insect interactions * tobacco plant s * jasmonic acid * manduca-sexta * cis-zeatin * responses * cytokinins * optimal defense * herbivores * inducible defense * Nicotiana attenuata * Manduca sexta * plant development * immunosenescence * phytohormones Subject RIV: ED - Physiology Impact factor: 5.901, year: 2016

  15. A simple and efficient micrografting method for stably transformed Nicotiana attenuata plants to examine shoot-root signaling

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    Kim Sang-Gyu

    2011-10-01

    Full Text Available Abstract To adjust their development to the environment, plants rely on specific signals that travel from shoot to root and vice versa. Here we describe an efficient micrografting protocol for Nicotiana attenuata, a useful tool for identifying these signals and understanding their functions. Additionally we analyzed transcript accumulation profiles of scions and rootstocks of grafts performed with wild-type and stably transformed N. attenuata. Our results are consistent with the source-to-sink movement of an sRNA silencing signal.

  16. Host-plant-mediated effects of Nadefensin on herbivore and pathogen resistance in Nicotiana attenuata

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    Baldwin Ian T

    2008-10-01

    Full Text Available Abstract Background The adage from Shakespeare, "troubles, not as single spies, but in battalions come," holds true for Nicotiana attenuata, which is commonly attacked by both pathogens (Pseudomonas spp. and herbivores (Manduca sexta in its native habitats. Defense responses targeted against the pathogens can directly or indirectly influence the responses against the herbivores. Nadefensin is an effective induced defense gene against the bacterial pathogen Pseudomonas syringae pv tomato (PST DC3000, which is also elicited by attack from M. sexta larvae, but whether this defense protein influences M. sexta's growth and whether M. sexta-induced Nadefensin directly or indirectly influences PST DC3000 resistance are unknown. Results M. sexta larvae consumed less on WT and on Nadefensin-silenced N. attenuata plants that had previously been infected with PST DC3000 than on uninfected plants. WT plants infected with PST DC3000 showed enhanced resistance to PST DC3000 and decreased leaf consumption by M. sexta larvae, but larval mass gain was unaffected. PST DC3000-infected Nadefensin-silenced plants were less resistant to subsequent PST DC3000 challenge, and on these plants, M. sexta larvae consumed less and gained less mass. WT and Nadefensin-silenced plants previously damaged by M. sexta larvae were better able to resist subsequent PST DC3000 challenges than were undamaged plants. Conclusion These results demonstrate that Na-defensin directly mediates defense against PST DC3000 and indirectly against M. sexta in N. attenuata. In plants that were previously infected with PST DC3000, the altered leaf chemistry in PST DC3000-resistant WT plants and PST DC3000-susceptible Nadefensin-silenced plants differentially reduced M. sexta's leaf consumption and mass gain. In plants that were previously damaged by M. sexta, the combined effect of the altered host plant chemistry and a broad spectrum of anti-herbivore induced metabolomic responses was more

  17. Source parameter estimates of echolocation clicks from wild pygmy killer whales (Feresa attenuata) (L)

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    Madsen, P. T.; Kerr, I.; Payne, R.

    2004-10-01

    Pods of the little known pygmy killer whale (Feresa attenuata) in the northern Indian Ocean were recorded with a vertical hydrophone array connected to a digital recorder sampling at 320 kHz. Recorded clicks were directional, short (25 μs) transients with estimated source levels between 197 and 223 dB re. 1 μPa (pp). Spectra of clicks recorded close to or on the acoustic axis were bimodal with peak frequencies between 45 and 117 kHz, and with centroid frequencies between 70 and 85 kHz. The clicks share characteristics of echolocation clicks from similar sized, whistling delphinids, and have properties suited for the detection and classification of prey targeted by this odontocete. .

  18. HSPRO controls early Nicotiana attenuata seedling growth during interaction with the fungus Piriformospora indica.

    Science.gov (United States)

    Schuck, Stefan; Camehl, Iris; Gilardoni, Paola A; Oelmueller, Ralf; Baldwin, Ian T; Bonaventure, Gustavo

    2012-10-01

    In a previous study aimed at identifying regulators of Nicotiana attenuata responses against chewing insects, a 26-nucleotide tag matching the HSPRO (ORTHOLOG OF SUGAR BEET Hs1(pro)(-)(1)) gene was found to be strongly induced after simulated herbivory (Gilardoni et al., 2010). Here we characterized the function of HSPRO during biotic interactions in transgenic N. attenuata plants silenced in its expression (ir-hspro). In wild-type plants, HSPRO expression was not only induced during simulated herbivory but also when leaves were inoculated with Pseudomonas syringae pv tomato DC3000 and roots with the growth-promoting fungus Piriformospora indica. Reduced HSPRO expression did not affect the regulation of direct defenses against Manduca sexta herbivory or P. syringae pv tomato DC3000 infection rates. However, reduced HSPRO expression positively influenced early seedling growth during interaction with P. indica; fungus-colonized ir-hspro seedlings increased their fresh biomass by 30% compared with the wild type. Grafting experiments demonstrated that reduced HSPRO expression in roots was sufficient to induce differential growth promotion in both roots and shoots. This effect was accompanied by changes in the expression of 417 genes in colonized roots, most of which were metabolic genes. The lack of major differences in the metabolic profiles of ir-hspro and wild-type colonized roots (as analyzed by liquid chromatography time-of-flight mass spectrometry) suggested that accelerated metabolic rates were involved. We conclude that HSPRO participates in a whole-plant change in growth physiology when seedlings interact with P. indica.

  19. Changes in cytokinins are sufficient to alter developmental patterns of defense metabolites in Nicotiana attenuata.

    Science.gov (United States)

    Brütting, Christoph; Schäfer, Martin; Vanková, Radomíra; Gase, Klaus; Baldwin, Ian T; Meldau, Stefan

    2017-01-01

    Plant defense metabolites are well known to be regulated developmentally. The optimal defense (OD) theory posits that a tssue's fitness values and probability of attack should determine defense metabolite allocations. Young leaves are expected to provide a larger fitness value to the plant, and therefore their defense allocations should be higher when compared with older leaves. The mechanisms that coordinate development with defense remain unknown and frequently confound tests of the OD theory predictions. Here we demonstrate that cytokinins (CKs) modulate ontogeny-dependent defenses in Nicotiana attenuata. We found that leaf CK levels highly correlate with inducible defense expressions with high levels in young and low levels in older leaves. We genetically manipulated the developmental patterns of two different CK classes by using senescence- and chemically inducible expression of CK biosynthesis genes. Genetically modifying the levels of different CKs in leaves was sufficient to alter ontogenic patterns of defense metabolites. We conclude that the developmental regulation of growth hormones that include CKs plays central roles in connecting development with defense and therefore in establishing optimal patterns of defense allocation in plants. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  20. Rapid modification of the insect elicitor N-linolenoyl-glutamate via a lipoxygenase-mediated mechanism on Nicotiana attenuata leaves

    Directory of Open Access Journals (Sweden)

    VanDoorn Arjen

    2010-08-01

    Full Text Available Abstract Background Some plants distinguish mechanical wounding from herbivore attack by recognizing specific constituents of larval oral secretions (OS which are introduced into plant wounds during feeding. Fatty acid-amino acid conjugates (FACs are major constituents of Manduca sexta OS and strong elicitors of herbivore-induced defense responses in Nicotiana attenuata plants. Results The metabolism of one of the major FACs in M. sexta OS, N-linolenoyl-glutamic acid (18:3-Glu, was analyzed on N. attenuata wounded leaf surfaces. Between 50 to 70% of the 18:3-Glu in the OS or of synthetic 18:3-Glu were metabolized within 30 seconds of application to leaf wounds. This heat-labile process did not result in free α-linolenic acid (18:3 and glutamate but in the biogenesis of metabolites both more and less polar than 18:3-Glu. Identification of the major modified forms of this FAC showed that they corresponded to 13-hydroxy-18:3-Glu, 13-hydroperoxy-18:3-Glu and 13-oxo-13:2-Glu. The formation of these metabolites occurred on the wounded leaf surface and it was dependent on lipoxygenase (LOX activity; plants silenced in the expression of NaLOX2 and NaLOX3 genes showed more than 50% reduced rates of 18:3-Glu conversion and accumulated smaller amounts of the oxygenated derivatives compared to wild-type plants. Similar to 18:3-Glu, 13-oxo-13:2-Glu activated the enhanced accumulation of jasmonic acid (JA in N. attenuata leaves whereas 13-hydroxy-18:3-Glu did not. Moreover, compared to 18:3-Glu elicitation, 13-oxo-13:2-Glu induced the differential emission of two monoterpene volatiles (β-pinene and an unidentified monoterpene in irlox2 plants. Conclusions The metabolism of one of the major elicitors of herbivore-specific responses in N. attenuata plants, 18:3-Glu, results in the formation of oxidized forms of this FAC by a LOX-dependent mechanism. One of these derivatives, 13-oxo-13:2-Glu, is an active elicitor of JA biosynthesis and differential

  1. Jasmonoyl-L-isoleucine coordinates metabolic networks required for anthesis and floral attractant emission in wild tobacco (Nicotiana attenuata).

    Science.gov (United States)

    Stitz, Michael; Hartl, Markus; Baldwin, Ian T; Gaquerel, Emmanuel

    2014-10-01

    Jasmonic acid and its derivatives (jasmonates [JAs]) play central roles in floral development and maturation. The binding of jasmonoyl-L-isoleucine (JA-Ile) to the F-box of CORONATINE INSENSITIVE1 (COI1) is required for many JA-dependent physiological responses, but its role in anthesis and pollinator attraction traits remains largely unexplored. Here, we used the wild tobacco Nicotiana attenuata, which develops sympetalous flowers with complex pollination biology, to examine the coordinating function of JA homeostasis in the distinct metabolic processes that underlie flower maturation, opening, and advertisement to pollinators. From combined transcriptomic, targeted metabolic, and allometric analyses of transgenic N. attenuata plants for which signaling deficiencies were complemented with methyl jasmonate, JA-Ile, and its functional homolog, coronatine (COR), we demonstrate that (1) JA-Ile/COR-based signaling regulates corolla limb opening and a JA-negative feedback loop; (2) production of floral volatiles (night emissions of benzylacetone) and nectar requires JA-Ile/COR perception through COI1; and (3) limb expansion involves JA-Ile-induced changes in limb fresh mass and carbohydrate metabolism. These findings demonstrate a master regulatory function of the JA-Ile/COI1 duet for the main function of a sympetalous corolla, that of advertising for and rewarding pollinator services. Flower opening, by contrast, requires JA-Ile signaling-dependent changes in primary metabolism, which are not compromised in the COI1-silenced RNA interference line used in this study. © 2014 American Society of Plant Biologists. All rights reserved.

  2. MYB8 Controls Inducible Phenolamide Levels by Activating Three Novel Hydroxycinnamoyl-Coenzyme A:Polyamine Transferases in Nicotiana attenuata[W][OA

    NARCIS (Netherlands)

    Onkokesung, N.; Gaquerel, E.; Kotkar, H.; Kaur, H.; Baldwin, I.T.; Galis, I.

    2012-01-01

    A large number of plants accumulate N-acylated polyamines (phenolamides [PAs]) in response to biotic and/or abiotic stress conditions. In the native tobacco (Nicotiana attenuata), the accumulation of two major PAs, caffeoylputrescine and dicaffeoylspermidine (DCS), after herbivore attack is known to

  3. Differences in Nicotine Metabolism of Two Nicotiana attenuata Herbivores Render Them Differentially Susceptible to a Common Native Predator

    Science.gov (United States)

    Kumar, Pavan; Rathi, Preeti; Schöttner, Matthias; Baldwin, Ian T.; Pandit, Sagar

    2014-01-01

    Background Nicotiana attenuata is attacked by larvae of both specialist (Manduca sexta) and generalist (Spodoptera exigua) lepidopteran herbivores in its native habitat. Nicotine is one of N. attenuata's important defenses. M. sexta is highly nicotine tolerant; whether cytochrome P450 (CYP)-mediated oxidative detoxification and/or rapid excretion is responsible for its exceptional tolerance remains unknown despite five decades of study. Recently, we demonstrated that M. sexta uses its nicotine-induced CYP6B46 to efflux midgut-nicotine into the hemolymph, facilitating nicotine exhalation that deters predatory wolf spiders (Camptocosa parallela). S. exigua's nicotine metabolism is uninvestigated. Methodology/Principal Findings We compared the ability of these two herbivores to metabolize, tolerate and co-opt ingested nicotine for defense against the wolf spider. In addition, we analyzed the spider's excretion to gain insights into its nicotine metabolism. Contrary to previous reports, we found that M. sexta larvae neither accumulate the common nicotine oxides (cotinine, cotinine N-oxide and nicotine N-oxide) nor excrete them faster than nicotine. In M. sexta larvae, ingestion of nicotine as well as its oxides increases the accumulation of CYP6B46 transcripts. In contrast, S. exigua accumulates nicotine oxides and exhales less (66%) nicotine than does M. sexta. Spiders prefer nicotine-fed S. exigua over M. sexta, a preference reversed by topical or headspace nicotine supplementation, but not ingested or topically-coated nicotine oxides, suggesting that externalized nicotine but not the nicotine detoxification products deter spider predation. The spiders also do not accumulate nicotine oxides. Conclusions Nicotine oxidation reduces S. exigua's headspace-nicotine and renders it more susceptible to predation by spiders than M. sexta, which exhales unmetabolized nicotine. These results are consistent with the hypothesis that generalist herbivores incur costs of

  4. HSPRO Controls Early Nicotiana attenuata Seedling Growth during Interaction with the Fungus Piriformospora indica1[C][W][OA

    Science.gov (United States)

    Schuck, Stefan; Camehl, Iris; Gilardoni, Paola A.; Oelmueller, Ralf; Baldwin, Ian T.; Bonaventure, Gustavo

    2012-01-01

    In a previous study aimed at identifying regulators of Nicotiana attenuata responses against chewing insects, a 26-nucleotide tag matching the HSPRO (ORTHOLOG OF SUGAR BEET Hs1pro-1) gene was found to be strongly induced after simulated herbivory (Gilardoni et al., 2010). Here we characterized the function of HSPRO during biotic interactions in transgenic N. attenuata plants silenced in its expression (ir-hspro). In wild-type plants, HSPRO expression was not only induced during simulated herbivory but also when leaves were inoculated with Pseudomonas syringae pv tomato DC3000 and roots with the growth-promoting fungus Piriformospora indica. Reduced HSPRO expression did not affect the regulation of direct defenses against Manduca sexta herbivory or P. syringae pv tomato DC3000 infection rates. However, reduced HSPRO expression positively influenced early seedling growth during interaction with P. indica; fungus-colonized ir-hspro seedlings increased their fresh biomass by 30% compared with the wild type. Grafting experiments demonstrated that reduced HSPRO expression in roots was sufficient to induce differential growth promotion in both roots and shoots. This effect was accompanied by changes in the expression of 417 genes in colonized roots, most of which were metabolic genes. The lack of major differences in the metabolic profiles of ir-hspro and wild-type colonized roots (as analyzed by liquid chromatography time-of-flight mass spectrometry) suggested that accelerated metabolic rates were involved. We conclude that HSPRO participates in a whole-plant change in growth physiology when seedlings interact with P. indica. PMID:22892352

  5. The essential role of jasmonic acid in plant-herbivore interactions--using the wild tobacco Nicotiana attenuata as a model.

    Science.gov (United States)

    Wang, Lei; Wu, Jianqiang

    2013-12-20

    The plant hormone jasmonic acid (JA) plays a central role in plant defense against herbivores. Herbivore damage elicits a rapid and transient JA burst in the wounded leaves and JA functions as a signal to mediate the accumulation of various secondary metabolites that confer resistance to herbivores. Nicotiana attenuata is a wild tobacco species that inhabits western North America. More than fifteen years of study and its unique interaction with the specialist herbivore insect Manduca sexta have made this plant one of the best models for studying plant-herbivore interactions. Here we review the recent progress in understanding the elicitation of JA accumulation by herbivore-specific elicitors, the regulation of JA biosynthesis, JA signaling, and the herbivore-defense traits in N. attenuata. Copyright © 2013. Published by Elsevier Ltd.

  6. A jasmonate ZIM-domain protein NaJAZd regulates floral jasmonic acid levels and counteracts flower abscission in Nicotiana attenuata plants.

    Science.gov (United States)

    Oh, Youngjoo; Baldwin, Ian T; Galis, Ivan

    2013-01-01

    Jasmonic acid is an important regulator of plant growth, development and defense. The jasmonate-ZIM domain (JAZ) proteins are key regulators in jasmonate signaling ubiquitously present in flowering plants but their functional annotation remains largely incomplete. Recently, we identified 12 putative JAZ proteins in native tobacco, Nicotiana attenuata, and initiated systematic functional characterization of these proteins by reverse genetic approaches. In this report, Nicotiana attenuata plants silenced in the expression of NaJAZd (irJAZd) by RNA interference were used to characterize NaJAZd function. Although NaJAZd transcripts were strongly and transiently up-regulated in the rosette leaves by simulated herbivory treatment, we did not observe strong defense-related phenotypes, such as altered herbivore performance or the constitutive accumulation of defense-related secondary metabolites in irJAZd plants compared to wild type plants, both in the glasshouse and the native habitat of Nicotiana attenuata in the Great Basin Desert, Utah, USA. Interestingly, irJAZd plants produced fewer seed capsules than did wild type plants as a result of increased flower abscission in later stages of flower development. The early- and mid-developmental stages of irJAZd flowers had reduced levels of jasmonic acid and jasmonoyl-L-isoleucine, while fully open flowers had normal levels, but these were impaired in NaMYB305 transcript accumulations. Previously, NaMYB305-silenced plants were shown to have strong flower abscission phenotypes and contained lower NECTARIN 1 transcript levels, phenotypes which are copied in irJAZd plants. We propose that the NaJAZd protein is required to counteract flower abscission, possibly by regulating jasmonic acid and jasmonoyl-L-isoleucine levels and/or expression of NaMYB305 gene in Nicotiana attenuata flowers. This novel insight into the function of JAZ proteins in flower and seed development highlights the diversity of functions played by jasmonates

  7. Avistamientos del delfín manchado, Stenella attenuata (Cetacea: Delphinidae en Bahía Culebra, Costa Rica, 1999-2000

    Directory of Open Access Journals (Sweden)

    Karina Rodríguez Sáenz

    2004-12-01

    Full Text Available Paralelo a un estudio de zooplancton (1999-2000, se hicieron observaciones a bordo de un bote inflable, sobre la presencia o ausencia de delfines a lo largo de un transecto (~8 km long en la parte central de Bahía Culebra (24 km² , Golfo de Papagayo. Se realizaron 34 muestreos en total y hubo avistamientos de delfines en 20 de ellos. La única especie de cetáceo observado en la Bahía fue el delfín manchado (Stenella attenuata. Estos avistamientos fueron más frecuentes durante la época lluviosa, en particular durante el mes de mayo de ambos años. La presencia de S. attenuata en Bahía Culebra podría estar asociada a la abundancia de presas potenciales como peces y moluscos (calamares, como se evidencia por las estadísticas pesqueras disponibles para la zona Pacífica de Costa RicaParallel to a zooplankton study (1999-2000 observations were made (from an inflatable boat, on the presence of dolphins along a transect (~8 km long on the axis of Culebra Bay (24 km² , Gulf of Papagayo, Pacific coast of Costa Rica. Dolphins were found during 20 of the 31 boat surveys conducted. The only species of cetacean found in the bay was Stenella attenuata, the spotted dolphin. These sightings were more frequent during the rainy season, particularly during the month of May of both years. The presence of S. attenuata in Culebra Bay might be associated to the abundances of fish and mollusks (their presumed prey: for example, squids, as evidenced by fishery statistics available for this zone of the Pacific coast of Costa Rica

  8. Modulation rate transfer functions from four species of stranded odontocete (Stenella longirostris, Feresa attenuata, Globicephala melas, and Mesoplodon densirostris).

    Science.gov (United States)

    Smith, Adam B; Pacini, Aude F; Nachtigall, Paul E

    2018-01-19

    Odontocete marine mammals explore the environment by rapidly producing echolocation signals and receiving the corresponding echoes, which likewise return at very rapid rates. Thus, it is important that the auditory system has a high temporal resolution to effectively process and extract relevant information from click echoes. This study used auditory evoked potential methods to investigate auditory temporal resolution of individuals from four different odontocete species, including a spinner dolphin (Stenella longirostris), pygmy killer whale (Feresa attenuata), long-finned pilot whale (Globicephala melas), and Blainville's beaked whale (Mesoplodon densirostris). Each individual had previously stranded and was undergoing rehabilitation. Auditory Brainstem Responses (ABRs) were elicited via acoustic stimuli consisting of a train of broadband tone pulses presented at rates between 300 and 2000 Hz. Similar to other studied species, modulation rate transfer functions (MRTFs) of the studied individuals followed the shape of a low-pass filter, with the ability to process acoustic stimuli at presentation rates up to and exceeding 1250 Hz. Auditory integration times estimated from the bandwidths of the MRTFs ranged between 250 and 333 µs. The results support the hypothesis that high temporal resolution is conserved throughout the diverse range of odontocete species.

  9. On the development of Cetacean extremities: II. Morphogenesis and histogenesis of the flippers in the spotted dolphin (Stenella attenuata).

    Science.gov (United States)

    Sedmera, D; Misek, I; Klima, M

    1997-04-01

    Externally, the flippers of Cetacea resemble fish fins, but their internal structure is entirely mammalian. They show, however, some adaptative deviations from the typical pattern of the mammalian extremities, the most striking of which is an increased number of phalanges. The aim of this study is to describe the course of the development of flippers in the spotted dolphin (Stenella attenuata) and compare its features with other similar species from an evolutionary perspective. Early stages of flipper development were studied histologically. Differentiation of cartilaginous anlagens of the skeleton progresses proximodistally, condensation in digital rays being evident sooner than chondrogenesis in the carpal region. In one specimen, the temporary presence of cartilaginous rudiments of two carpal elements, which are not found in adults, was observed. At all examined stages, phalangeal number progressively increases up to (radial to ulnar) 3, 7, 7, 5, 3 in the most advanced stage. The reason for this condition is the specialised function of these limb-like structures. It is a classical example of convergence, in which mammalian extremities change their form to emulate the fin function. A similar condition is found in another group of originally terrestrial animals secondarily fully adapted to the aquatic mode of life-Ichyosauria (Reptilia).

  10. Ectopic Terpene Synthase Expression Enhances Sesquiterpene Emission in Nicotiana attenuata without Altering Defense or Development of Transgenic Plants or Neighbors1[W

    Science.gov (United States)

    Schuman, Meredith C.; Palmer-Young, Evan C.; Schmidt, Axel; Gershenzon, Jonathan; Baldwin, Ian T.

    2014-01-01

    Sesquiterpenoids, with approximately 5,000 structures, are the most diverse class of plant volatiles with manifold hypothesized functions in defense, stress tolerance, and signaling between and within plants. These hypotheses have often been tested by transforming plants with sesquiterpene synthases expressed behind the constitutively active 35S promoter, which may have physiological costs measured as inhibited growth and reduced reproduction or may require augmentation of substrate pools to achieve enhanced emission, complicating the interpretation of data from affected transgenic lines. Here, we expressed maize (Zea mays) terpene synthase10 (ZmTPS10), which produces (E)-α-bergamotene and (E)-β-farnesene, or a point mutant ZmTPS10M, which produces primarily (E)-β-farnesene, under control of the 35S promoter in the ecological model plant Nicotiana attenuata. Transgenic N. attenuata plants had specifically enhanced emission of target sesquiterpene(s) with no changes detected in their emission of any other volatiles. Treatment with herbivore or jasmonate elicitors induces emission of (E)-α-bergamotene in wild-type plants and also tended to increase emission of (E)-α-bergamotene and (E)-β-farnesene in transgenics. However, transgenics did not differ from the wild type in defense signaling or chemistry and did not alter defense chemistry in neighboring wild-type plants. These data are inconsistent with within-plant and between-plant signaling functions of (E)-β-farnesene and (E)-α-bergamotene in N. attenuata. Ectopic sesquiterpene emission was apparently not costly for transgenics, which were similar to wild-type plants in their growth and reproduction, even when forced to compete for common resources. These transgenics would be well suited for field experiments to investigate indirect ecological effects of sesquiterpenes for a wild plant in its native habitat. PMID:25187528

  11. Multi-scale biomarker evaluation of the toxicity of a commercial azo dye (Disperse Red 1) in an animal model, the freshwater cnidarian Hydra attenuata.

    Science.gov (United States)

    de Jong, Laetitia; Pech, Nicolas; de Aragão Umbuzeiro, Gisela; Moreau, Xavier

    2016-06-01

    Acute (24 h, 48 h, 72 h) and chronic (7 days) tests have been performed to evaluate the effects of the commercial azo dye Disperse Red 1 (DR1) using various biomarkers in the freshwater invertebrate Hydra attenuata. Morphological changes have been selected to calculate ecotoxicological thresholds for sublethal and lethal DR1 concentrations. A multinomial logistic model showed that the probability of each morphological stage occurrence was function of concentration, time and interaction between both. Results of oxidative balance parameter measurements (72 h and 7 days) suggest that polyps set up defense mechanisms to limit lipid peroxidation caused by DR1. DR1 exposure at hormetic concentrations induces increase of asexual reproductive rates. This result suggests (1) an impact on the fitness-related phenotypical traits and (2) trade-offs between reproduction and maintenance to allow the population to survive harsher conditions. Changes in serotonin immuno-labeling in polyps showing alterations in feeding behavior suggest that chronic DR1 exposure impaired neuronal processes related to ingesting behavior in H. attenuata. This ecotoxicity study sheds light on the possible serotonin function in Hydra model and reports for the first time that serotonin could play a significant role in feeding behavior. This study used a multi-scale biomarker approach investigating biochemical, morphological, reproductive and behavioral endpoints in Hydra attenuata. This organism is proposed for a pertinent animal model to assess ecotoxicological impact of pollutant mixtures in freshwater environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Tarennanosides A-H, eight new lignan glucosides from Tarenna attenuata and their protective effect on H2O2-induced impairment in PC12 cells.

    Science.gov (United States)

    Yang, Xian-Wen; He, Hong-Ping; Du, Zhi-Zhi; Liu, Hai-Yang; Di, Ying-Tong; Ma, Yan-Lin; Wang, Fang; Lin, Hua; Zuo, Yi-Qing; Li, Ling; Hao, Xiao-Jiang

    2009-04-01

    Eight new lignan glucosides, tarennanosides A-H (1-8, resp.), were isolated from the whole plant of Tarenna attenuata, together with three known compounds, fernandoside, (-)-lyoniresinol, and (-)-isolariciresinol. The planar structures of new compounds were elucidated mainly by analysis of physical and spectroscopic data, and the absolute configurations were determined by acid hydrolysis as well as CD spectroscopy. Compounds 1 and 2 exhibited potent antioxidant activities against H2O2-induced impairment in PC12 cells. Preliminary mechanism study by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method showed that these two compounds could act as radical scavengers.

  13. Avistamientos del delfín manchado, Stenella attenuata (Cetacea: Delphinidae) en Bahía Culebra, Costa Rica, 1999-2000

    OpenAIRE

    Rodríguez Sáenz, Karina; Rodríguez-Fonseca, Javier

    2016-01-01

    Parallel to a zooplankton study (1999-2000) observations were made (from an inflatable boat), on the presence of dolphins along a transect (~8 km long) on the axis of Culebra Bay (24 km2), Gulf of Papagayo, Pacific coast of Costa Rica. Dolphins were found during 20 of the 31 boat surveys conducted. The only species of cetacean found in the bay was Stenella attenuata, the spotted dolphin. These sightings were more frequent during the rainy season, particularly during the month of May of both y...

  14. Avistamientos del delfín manchado, Stenella attenuata (Cetacea: Delphinidae) en Bahía Culebra, Costa Rica, 1999-2000

    OpenAIRE

    Karina Rodríguez Sáenz; Javier Rodríguez-Fonseca

    2004-01-01

    Paralelo a un estudio de zooplancton (1999-2000), se hicieron observaciones a bordo de un bote inflable, sobre la presencia o ausencia de delfines a lo largo de un transecto (~8 km long) en la parte central de Bahía Culebra (24 km² ), Golfo de Papagayo. Se realizaron 34 muestreos en total y hubo avistamientos de delfines en 20 de ellos. La única especie de cetáceo observado en la Bahía fue el delfín manchado (Stenella attenuata). Estos avistamientos fueron más frecuentes durante la época lluv...

  15. Presencia y patrones de comportamiento del delfín manchado costero, Stenella attenuata (Cetacea: Delphinidae) en el Golfo de Papagayo, Costa Rica

    OpenAIRE

    Laura May-Collado; Alvaro Morales Ramírez

    2014-01-01

    Los delfines se caracterizan por una increíble versatilidad, la cual les ha permitido responder a los cambios estacionales de su ambiente. Dicha variación estacional en los patrones de comportamiento se considera poco conocida en delfines que habitan aguas tropicales. El delfín manchado (forma costera) Stenella attenuata graffmani, parece ser la única especie de cetáceo residente en el Golfo de Papagayo, área que se caracteriza por una estacionalidad muy bien definida. El objetivo de este tra...

  16. Primeros registros de la Orca pigmea Feresa attenuata (Cetacea, delphinidae) y del Cachalote enano Kogia simus (Cetacea, physeteridae) en Ecuador continental

    OpenAIRE

    Félix, F; Haase, B.; Samaniego, J.

    1996-01-01

    Se presenta información sobre los primeros registros de la orca pigmea (Feresa attenuata) y del cachalote enano (Kogia simus) realizados en aguas costeras de Ecuador. La información se basa en un espécímen joven de orca pimea encontrado en la costa y en la cabeza colectada de un cachalote enano atrapado en una red agallera. Además se informa sobre el primer espécimen de un cachalote enano (K. simus) colectado en las islas Galápagos.

  17. Tissue specific diurnal rhythms of metabolites and their regulation during herbivore attack in a native tobacco, Nicotiana attenuata.

    Directory of Open Access Journals (Sweden)

    Sang-Gyu Kim

    Full Text Available Ecological performance is all about timing and the endogenous clock that allows the entrainment of rhythms and anticipation of fitness-determining events is being rapidly characterized. How plants anticipate daily abiotic stresses, such as cold in early mornings and drought at noon, as well as biotic stresses, such as the timing of pathogen infections, is being explored, but little is known about the clock's role in regulating responses to insect herbivores and mutualists, whose behaviors are known to be strongly diurnally regulated and whose attack is known to reconfigure plant metabolomes. We developed a liquid chromatography-mass spectrometry procedure and analyzed its output with model-based peak picking algorithms to identify metabolites with diurnal accumulation patterns in sink/source leaves and roots in an unbiased manner. The response of metabolites with strong diurnal patterns to simulated attack from the specialist herbivore, Manduca sexta larvae was analyzed and annotated with in-house and public databases. Roots and leaves had largely different rhythms and only 10 ions of 182 oscillating ions in leaves and 179 oscillating ions in roots were rhythmic in both tissues: root metabolites mainly peaked at dusk or night, while leaf metabolites peaked during the day. Many oscillating metabolites showed tissue-specific regulation by simulated herbivory of which systemic responses in unattacked tissues were particularly pronounced. Diurnal and herbivory-elicited accumulation patterns of disaccharide, phenylalanine, tyrosine, lyciumoside I, coumaroyl tyramine, 12-oxophytodienoic acid and jasmonic acid and those of their related biosynthetic transcripts were examined in detail. We conclude that oscillating metabolites of N. attenuata accumulate in a highly tissue-specific manner and the patterns reveal pronounced diurnal rhythms in the generalized and specialized metabolism that mediates the plant's responses to herbivores and mutualists. We

  18. The structure of the culturable root bacterial endophyte community of Nicotiana attenuata is organized by soil composition and host plant ethylene production and perception.

    Science.gov (United States)

    Long, Hoang Hoa; Sonntag, Dorothea G; Schmidt, Dominik D; Baldwin, Ian T

    2010-01-01

    *A plant's bacterial endophyte community is thought to be recruited from the rhizosphere, but how this recruitment is influenced by the plant's phytohormone signaling is unknown. Ethylene regulates plant-microbe interactions; here, we assess the role of ethylene in the recruitment of culturable endophytic bacteria from native soils. *We grew wild-type Nicotiana attenuata plants and isogenic transformed plants deficient in ethylene biosynthesis (ir-aco1) or perception (35S-etr1) in four native soils and quantified the extent of culturable bacterial endophyte colonization (by plate counting) and diversity (by amplified rDNA restriction analysis and 16S rDNA sequencing). *The endophyte community composition was influenced by soil type and ethylene signaling. Plants grown in organic (vs mineral) soils harbored a more diverse community and plants impaired in ethylene homeostasis harbored a less diverse community than wild-type plants. Wild-type and ethylene signaling-impaired plants fostered distinct bacteria in addition to common ones. In vitro re-colonization by common and genotype-specific isolates demonstrated the specificity of some associations and the susceptibility of 35S-etr1 seedlings to all tested bacterial isolates, suggesting an active process of colonization driven by plant- and microbe-specific genes. *We propose that soil composition and ethylene homeostasis play central roles in structuring the bacterial endophyte community in N. attenuata roots.

  19. HSPRO acts via SnRK1-mediated signaling in the regulation of Nicotiana attenuata seedling growth promoted by Piriformospora indica.

    Science.gov (United States)

    Schuck, Stefan; Baldwin, Ian T; Bonaventure, Gustavo

    2013-04-01

    Nicotiana attenuata HSPRO (NaHSPRO) is a negative regulator of seedling growth promoted by the fungus Piriformospora indica. Homologs of NaHSPRO in Arabidopsis thaliana (i.e., AtHSPRO1 and AtHSPRO2) are known to physically interact with the AKINβγ subunit of the SnRK1 complex. To investigate whether NaHSPRO is associated with SnRK1 function during the stimulation of seedling growth by P. indica, we studied N. attenuata plants silenced in the expression of NaGAL83 (as-gal83 plants)--a gene that encodes for the regulatory β-subunit of SnRK1--and plants silenced in the expression of both NaHSPRO and NaGAL83 (ir-hspro/as-gal83 plants). The results showed that P. indica differentially stimulated the growth of both as-gal83 and ir-hspro/as-gal83 seedlings compared with control seedlings, with a magnitude similar to that observed in ir-hspro seedlings. Thus, we showed that, similar to NaHSPRO, NaGAL83 is a negative regulator of seedling growth stimulated by P. indica. We propose that the effect of NaHSPRO on seedling growth is associated with SnRK1 signaling.

  20. Getting to know you: Identification of pygmy killer whales (Feresa attenuata and melon-headed whales (Peponocephala electra under challenging conditions

    Directory of Open Access Journals (Sweden)

    Salvatore Siciliano

    2015-12-01

    Full Text Available Abstract Melon-headed whale (Peponocephala electra and Pygmy killer whale (Feresa attenuata are very poorly known species and are often confused with each other. We examined in detail Figure 3 in MARIGO and GIFFONI (2010 who reported that two melon-headed whales were taken in a surface driftnet about 90 nm off Santos, Brazil. We concluded they were in fact pygmy killer whales and explain our reasoning. To aid in future identifications, we illustrate and describe some of the main differences between these two species of small cetaceans. The incident reported by MARIGO and GIFFONI (2010 might represent the 'tip of the iceberg' regarding the incidental catches of cetaceans by pelagic drift nets off Brazil. Offshore driftnetting operating along the south-southeastern coast of Brazil may threaten pygmy killer whales.

  1. Nicotiana attenuata α-DIOXYGENASE1 through its production of 2-hydroxylinolenic acid is required for intact plant defense expression against attack from Manduca sexta larvae.

    Science.gov (United States)

    Gaquerel, Emmanuel; Steppuhn, Anke; Baldwin, Ian T

    2012-10-01

    Nicotiana attenuata α-DIOXYGENASE1 (α-DOX1) is an oxylipin-forming gene elicited during herbivory by fatty acid amino acid conjugates (FACs) contained in oral secretions of Manduca sexta. To understand the roles of Naα-DOX1 and its major product, 2-hydroxylinolenic acid (2-hydroxylinolenic acid), in N. attenuata's anti-herbivore defenses, we used a transgenic line specifically silenced in Naα-DOX1 expression (ir-α-dox1) and monitored 2-HOT production in M. sexta-damaged tissues and its role in influencing the production of direct defense compounds and resistance to this insect. Attack by M. sexta larvae amplified 2-HOT formation at the feeding sites; a reaction probably facilitated by Naα-DOX1's high pH optimum which allows 2-HOT formation to occur in the more alkaline conditions at the feeding sites or potentially in the insect mouth parts after the leaf tissue is ingested. Manduca sexta larvae performed better on ir-α-dox1 plants than on wild-type (WT) plants as a result of attenuated herbivory-specific JA and 2-HOT bursts as well as JA-inducible well-established defenses (nicotine, caffeoylputrescine and trypsin proteinase inhibitors). Repeated applications of 2-HOT to wounds before insect feeding partly amplified JA-controlled defenses and restored the resistance of ir-α-dox1 plants. We conclude that 2-HOT, produced by attack-activated α-DOX1 activity, participates in defense activation during insect feeding. © 2012 The Authors New Phytologist © 2012 New Phytologist Trust.

  2. Presencia y patrones de comportamiento del delfín manchado costero, Stenella attenuata (Cetacea: Delphinidae en el Golfo de Papagayo, Costa Rica

    Directory of Open Access Journals (Sweden)

    Laura May-Collado

    2005-06-01

    Full Text Available Los delfines se caracterizan por una increíble versatilidad, la cual les ha permitido responder a los cambios estacionales de su ambiente. Dicha variación estacional en los patrones de comportamiento se considera poco conocida en delfines que habitan aguas tropicales. El delfín manchado (forma costera Stenella attenuata graffmani, parece ser la única especie de cetáceo residente en el Golfo de Papagayo, área que se caracteriza por una estacionalidad muy bien definida. El objetivo de este trabajo es determinar si esta estacionalidad influencia el tamaño del grupo, la presencia y patrones de comportamiento de esta especie de delfín en el golfo. Usando transectos en banda se recorrieron dos localidades del Golfo de Papagayo. El tamaño del grupo varío de uno a 50 individuos, con una media de 10.16 (DS =9.61. Las actividades alimentarias fueron más intensas que las interacciones sociales y de desplazamiento, las cuales siguieron un ordenamiento diario y estacional. Se describieron dos técnicas principales de forrajeo las cuales parecen estar asociadas con el tamaño del grupo y localidad dentro del golfo. La variación diaria en los patrones de comportamiento parecen estar relacionados con la disponibilidad, distribución, y arreglo espacial de las presas. De igual manera, la variación estacional de estas actividades probablemente esta asociada por la disponibilidad de alimento, tal como ha sido observado en un mayor número de grupos y una mayor inversión de tiempo en actividades de alimentación durante la época seca y finales de las lluviasOccurrence and behavioral patterns of the spotted coastal dolphin Stenella attenuata (Cetacea: Delphinidae in the Gulf of Papagayo, Costa Rica. Dolphins are characterized by a significant behavioral versatility, which allows them to respond to environmental seasonality. Seasonal variation in dolphin behavior in tropical waters is not well known. Stenella attenuata graffmani is a resident dolphin

  3. Small-scale estimation of relative abundance for the coastal spotted dolphins (Stenella attenuata in Costa Rica: the effect of habitat and seasonality

    Directory of Open Access Journals (Sweden)

    Laura J May-Collado

    2012-04-01

    Full Text Available The coastal spotted dolphin (Stenella attenuata graffmani is one of the most common species of dolphin in inshore Pacific waters of Costa Rica. We conducted surveys in protected waters of the Papagayo Gulf, Costa Rica, to determine relative abundance of dolphins in relation to environmental variables. We used Generalized Additive Models to investigate the influence of a particular set of environmental factors and determine inter-annual trends in relative abundance. School sizes ranged from 1 to 50 individuals ( mean 9.95, SD=10.28. The number of dolphins increased linearly with water depth and transparency, and non-linearly with the dissolved oxygen concentration. High variability in the relative abundance occurred during the dry season (January-April. A previous study on this population found that high number of groups are involved in foraging activities during the dry season. Seasonal changes in relative abundance probably are associated with food availability, a variable that we did not measure. Understanding local resident populations may have important implications for conservation and management strategies. Large-scale studies may overlook variables affecting the abundance of local resident populations that may be detected with studies on a smaller scale such as this one.

  4. A Nicotiana attenuata cell wall invertase inhibitor (NaCWII) reduces growth and increases secondary metabolite biosynthesis in herbivore-attacked plants.

    Science.gov (United States)

    Ferrieri, Abigail P; Arce, Carla C M; Machado, Ricardo A R; Meza-Canales, Ivan D; Lima, Eraldo; Baldwin, Ian T; Erb, Matthias

    2015-10-01

    Plant invertases are sucrolytic enzymes that are essential for the regulation of carbohydrate metabolism and source-sink relationships. While their activity has been well documented during abiotic and biotic stresses, the role of proteinaceous invertase inhibitors in regulating these changes is unknown. Here, we identify a putative Nicotiana attenuata cell wall invertase inhibitor (NaCWII) which is strongly up-regulated in a jasmonate (JA)-dependent manner following simulated attack by the specialist herbivore Manduca sexta. To understand the role of NaCWII in planta, we silenced its expression by RNA interference and measured changes in primary and secondary metabolism and plant growth following simulated herbivory. NaCWII-silenced plants displayed a stronger depletion of carbohydrates and a reduced capacity to increase secondary metabolite pools relative to their empty vector control counterparts. This coincided with the attenuation of herbivore-induced CWI inhibition and growth suppression characteristic of wild-type plants. Together our findings suggest that NaCWII may act as a regulatory switch located downstream of JA accumulation which fine-tunes the plant's balance between growth and defense metabolism under herbivore attack. Although carbohydrates are not typically viewed as key factors in plant growth and defense, our study shows that interfering with their catabolism strongly influences plant responses to herbivory. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  5. NaJAZh Regulates a Subset of Defense Responses against Herbivores and Spontaneous Leaf Necrosis in Nicotiana attenuata Plants[C][W][OA

    Science.gov (United States)

    Oh, Youngjoo; Baldwin, Ian T.; Gális, Ivan

    2012-01-01

    The JASMONATE ZIM DOMAIN (JAZ) proteins function as negative regulators of jasmonic acid signaling in plants. We cloned 12 JAZ genes from native tobacco (Nicotiana attenuata), including nine novel JAZs in tobacco, and examined their expression in plants that had leaves elicited by wounding or simulated herbivory. Most JAZ genes showed strong expression in the elicited leaves, but NaJAZg was mainly expressed in roots. Another novel herbivory-elicited gene, NaJAZh, was analyzed in detail. RNA interference suppression of this gene in inverted-repeat (ir)JAZh plants deregulated a specific branch of jasmonic acid-dependent direct and indirect defenses: irJAZh plants showed greater trypsin protease inhibitor activity, 17-hydroxygeranyllinalool diterpene glycosides accumulation, and emission of volatile organic compounds from leaves. Silencing of NaJAZh also revealed a novel cross talk in JAZ-regulated secondary metabolism, as irJAZh plants had significantly reduced nicotine levels. In addition, irJAZh spontaneously developed leaf necrosis during the transition to flowering. Because the lesions closely correlated with the elevated expression of programmed cell death genes and the accumulations of salicylic acid and hydrogen peroxide in the leaves, we propose a novel role of the NaJAZh protein as a repressor of necrosis and/or programmed cell death during plant development. PMID:22496510

  6. The Sesquiterpenes(E-ß-Farnesene and (E-α-Bergamotene Quench Ozone but Fail to Protect the Wild Tobacco Nicotiana attenuata from Ozone, UVB, and Drought Stresses.

    Directory of Open Access Journals (Sweden)

    Evan C Palmer-Young

    Full Text Available Among the terpenes, isoprene (C5 and monoterpene hydrocarbons (C10 have been shown to ameliorate abiotic stress in a number of plant species via two proposed mechanisms: membrane stabilization and direct antioxidant effects. Sesquiterpene hydrocarbons (C15 not only share the structural properties thought to lend protective qualities to isoprene and monoterpene hydrocarbons, but also react rapidly with ozone, suggesting that sesquiterpenes may similarly enhance tolerance of abiotic stresses. To test whether sesquiterpenes protect plants against ozone, UVB light, or drought, we used transgenic lines of the wild tobacco Nicotiana attenuata. The transgenic plants expressed a maize terpene synthase gene (ZmTPS10 which produced a blend of (E-ß-farnesene and (E-α-bergamotene, or a point mutant of the same gene (ZmTPS10M which produced (E-ß-farnesene alone,. (E-ß-farnesene exerted a local, external, and transient ozone-quenching effect in ozone-fumigated chambers, but we found no evidence that enhanced sesquiterpene production by the plant inhibited oxidative damage, or maintained photosynthetic function or plant fitness under acute or chronic stress. Although the sesquiterpenes (E-ß-farnesene and (E-α-bergamotene might confer benefits under intermittent heat stress, which was not tested, any roles in relieving abiotic stress may be secondary to their previously demonstrated functions in biotic interactions.

  7. The Sesquiterpenes(E)-ß-Farnesene and (E)-α-Bergamotene Quench Ozone but Fail to Protect the Wild Tobacco Nicotiana attenuata from Ozone, UVB, and Drought Stresses.

    Science.gov (United States)

    Palmer-Young, Evan C; Veit, Daniel; Gershenzon, Jonathan; Schuman, Meredith C

    2015-01-01

    Among the terpenes, isoprene (C5) and monoterpene hydrocarbons (C10) have been shown to ameliorate abiotic stress in a number of plant species via two proposed mechanisms: membrane stabilization and direct antioxidant effects. Sesquiterpene hydrocarbons (C15) not only share the structural properties thought to lend protective qualities to isoprene and monoterpene hydrocarbons, but also react rapidly with ozone, suggesting that sesquiterpenes may similarly enhance tolerance of abiotic stresses. To test whether sesquiterpenes protect plants against ozone, UVB light, or drought, we used transgenic lines of the wild tobacco Nicotiana attenuata. The transgenic plants expressed a maize terpene synthase gene (ZmTPS10) which produced a blend of (E)-ß-farnesene and (E)-α-bergamotene, or a point mutant of the same gene (ZmTPS10M) which produced (E)-ß-farnesene alone,. (E)-ß-farnesene exerted a local, external, and transient ozone-quenching effect in ozone-fumigated chambers, but we found no evidence that enhanced sesquiterpene production by the plant inhibited oxidative damage, or maintained photosynthetic function or plant fitness under acute or chronic stress. Although the sesquiterpenes (E)-ß-farnesene and (E)-α-bergamotene might confer benefits under intermittent heat stress, which was not tested, any roles in relieving abiotic stress may be secondary to their previously demonstrated functions in biotic interactions.

  8. Small-scale estimation of relative abundance for the coastal spotted dolphins (Stenella attenuata in Costa Rica: the effect of habitat and seasonality

    Directory of Open Access Journals (Sweden)

    Laura J May-Collado

    2012-04-01

    Full Text Available The coastal spotted dolphin (Stenella attenuata graffmani is one of the most common species of dolphin in inshore Pacific waters of Costa Rica. We conducted surveys in protected waters of the Papagayo Gulf, Costa Rica, to determine relative abundance of dolphins in relation to environmental variables. We used Generalized Additive Models to investigate the influence of a particular set of environmental factors and determine inter-annual trends in relative abundance. School sizes ranged from 1 to 50 individuals ( mean 9.95, SD=10.28. The number of dolphins increased linearly with water depth and transparency, and non-linearly with the dissolved oxygen concentration. High variability in the relative abundance occurred during the dry season (January-April. A previous study on this population found that high number of groups are involved in foraging activities during the dry season. Seasonal changes in relative abundance probably are associated with food availability, a variable that we did not measure. Understanding local resident populations may have important implications for conservation and management strategies. Large-scale studies may overlook variables affecting the abundance of local resident populations that may be detected with studies on a smaller scale such as this one.El delfín manchado costero (Stenella attenuata graffmani es una de las especies de delfines mas comunes de las aguas costeras del Pacifico de Costa Rica. En este estudio realizamos muestreos dentro de las aguas protegidas del Golfo de Papagayo para determinar su abundancia relativa en relación a características físico-químicas de su hábitat. Usamos modelos aditivos generalizados para investigar la influencia de un juego de variables ambientales y determinar tendencias inter-anuales en la abundancia relativa. El tamaño de los grupos varió de 1 a 50 individuos (promedio 9.95, SD=10.28. La cantidad de delfines aumentó linealmente con la profundidad y claridad del

  9. ISSR and AFLP analysis of the temporal and spatial population structure of the post-fire annual, Nicotiana attenuata, in SW Utah

    Directory of Open Access Journals (Sweden)

    Preston Catherine A

    2004-09-01

    Full Text Available Abstract Background The native annual tobacco, Nicotiana attenuata, is found primarily in large ephemeral populations (typically for less than 3 growing seasons after fires in sagebrush and pinyon-juniper ecosystems and in small persistent populations (for many growing seasons in isolated washes typically along roadsides throughout the Great Basin Desert of the SW USA. This distribution pattern is due to its unusual germination behavior. Ephemeral populations are produced by the germination of dormant seeds from long-lived seed banks which are stimulated to germinate by a combination of unidentified positive cues found in wood smoke and the removal of inhibitors leached from the unburned litter of the dominant vegetation. Persistent populations may result where these inhibitors do not exist, as in washes or along disturbed roadsides. To determine if this germination behavior has influenced population structure, we conducted an AFLP (244 individuals, ISSR (175 individuals and ISSR+ AFLP (175 individuals analysis on plants originating from seed collected from populations growing in 11 wash and burns over 11 years from the SW USA. Results Genetic variance as measured by both ISSR and AFLP markers was low among sites and comparatively higher within populations. Cluster analysis of the Utah samples with samples collected from Arizona, California, and Oregon as out-groups also did not reveal patterns. AMOVA analysis of the combined AFLP and ISSR data sets yielded significantly low genetic differentiation among sites (Φct, moderate among populations within sites (Φsc and higher genetic differentiation within populations (Φst. Conclusions We conclude that the seed dormancy of this post-fire annual and its resulting age structure in conjunction with natural selection processes are responsible for significantly low among sites and comparatively high within-population genetic variation observed in this species.

  10. Whistle characteristics and daytime dive behavior in pantropical spotted dolphins (Stenella attenuata) in Hawai'i measured using digital acoustic recording tags (DTAGs).

    Science.gov (United States)

    Silva, Tammy L; Mooney, T Aran; Sayigh, Laela S; Tyack, Peter L; Baird, Robin W; Oswald, Julie N

    2016-07-01

    This study characterizes daytime acoustic and dive behavior of pantropical spotted dolphins (Stenella attenuata) in Hawai'i using 14.58 h of data collected from five deployments of digital acoustic recording tags (DTAG3) in 2013. For each tagged animal, the number of whistles, foraging buzzes, dive profiles, and dive statistics were calculated. Start, end, minimum, and maximum frequencies, number of inflection points and duration were measured from 746 whistles. Whistles ranged in frequency from 9.7 ± 2.8 to 19.8 ± 4.2 kHz, had a mean duration of 0.7 ± 0.5 s and a mean of 1.2 ± 1.2 inflection points. Thirteen foraging buzzes were recorded across all tags. Mean dive depth and duration were 16 ± 9 m and 1.9 ± 1.0 min, respectively. Tagged animals spent the majority of time in the upper 10 m (76.9% ± 16.1%) of the water column. Both whistle frequency characteristics and dive statistics measured here were similar to previously reported values for spotted dolphins in Hawai'i. Shallow, short dive profiles combined with few foraging buzzes provide evidence that little spotted dolphin feeding behavior occurs during daytime hours. This work represents one of the first successful DTAG3 studies of small pelagic delphinids, providing rare insights into baseline bioacoustics and dive behavior.

  11. [Distribution and environmental conditions related to the behavior in the bottlenose dolphin (Tursiops truncatus) and the spotted dolphin (Stenella attenuata) (Cetacea: Delphinidae) in Golfo Dulce, Costa Rica].

    Science.gov (United States)

    Cubero-Pardo, Priscilla

    2007-06-01

    Habitat characteristics influencing behavior in animal species vary locally. The influence that a particular environmental characteristic can have on a species depends not only on other variables, but on morphological, physiological and social conditions of that species. In this study, developed from June 1996 to July 1997, I studied whether specific behaviors are related to particular distribution areas and environmental factors in the bottlenose (Tursiops truncatus) and the spotted dolphin (Stenella attenuata). The study area was covered along oblicuous linear transects, and the behavior of single groups was observed from 15 min to 5 h. Environmental factors such as depth, temperature, salinity and distance from shore, among others, were considered. For the bottlenose dolphin, foraging/feeding activities showed exclusive coincidence with river mouths, coral reef and mangrove areas, while social and milling activities where seen close to feeding areas. Traveling occurred along different points parallel to the coast, with a low percentage of cases across the gulf (16.56 %), suggesting that the bottlenose rarely crosses from one side to the other. In the spotted dolphin, several behaviors were observed simultaneously in the schools and it was not possible to associate areas with particular behaviors. The lack of significant relationships among activities and particular environmental variables (ANOVA tests) is attributed to three aspects: (a) transitions among activities generally occurred into a low variable area, (b) dolphins often traveled along large areas without changing activities and (c) environmental conditions in Golfo Dulce are homogeneous. In the two species the highest average in the number of individuals per group corresponded to the category of active socializing, followed by traveling, passive socializing and feeding. In the case of the bottlenose dolphin, the smallest group size was associated with feeding activities (ANOVA, F= 2.624, p=0.037, n=156

  12. Herbivore defense responses and associated herbivore defense mechanism as revealed by comparing a resistant wild soybean with a susceptible cultivar

    Directory of Open Access Journals (Sweden)

    Xiaoyi Wang

    2015-12-01

    Full Text Available Plants have evolved sophisticated defense mechanisms against herbivores to help them adapt to the environment. Understanding the defense mechanisms in plants can help us control insects in a more effective manner. In this study, we found that compared with Tianlong 2 (a cultivated soybean with insect susceptibility, ED059 (a wild soybean line with insect resistance contains sharper pubescence tips, as well as lower transcript levels of wound-induced protein kinase (WIPK and salicylic acid-induced protein kinase (SIPK, which are important mitogen-activated protein kinases involved in early defense response to herbivores. The observed lower transcript levels of WIPK and SIPK induced higher levels of jasmonic acid (JA, JA biosynthesis enzymes (AOC3 and some secondary metabolites in ED059. Functional analysis of the KTI1 gene via Agrobacterium-mediated transformation in Arabidopsis thaliana indicated that it plays an important role in herbivore defense in ED059. We further investigated the molecular response of third-instar Helicoverpa armigera (Hübner larvae to Tianlong 2 and ED059. We found apoptotic cells only in the midguts of larvae that fed on ED059. Compared with larvae reared on the susceptible cultivar Tianlong 2, transcript levels of catalase (CAT and glutathione S-transferase (GST were up-regulated, whereas those of CAR, CHSB, and TRY were down-regulated in larvae that fed on the highly resistant variety ED059. We propose that these differences underlie the different herbivore defense responses of ED059 and Tianlong 2.

  13. RNAi-mediated silencing of the HD-Zip gene HD20 in Nicotiana attenuata affects benzyl acetone emission from corollas via ABA levels and the expression of metabolic genes

    Science.gov (United States)

    2012-01-01

    Background The N. attenuata HD20 gene belongs to the homeodomain-leucine zipper (HD-Zip) type I family of transcription factors and it has been previously associated with the regulation of ABA accumulation in leaves and the emission of benzyl acetone (BA; 4-phenyl-2-butanone) from night flowers. In this study, N. attenuata plants stably reduced in the expression of HD20 (ir-hd20) were generated to investigate the mechanisms controlling the emission of BA from night flowers. Results The expression of HD20 in corollas of ir-hd20 plants was reduced by 85 to 90% compared to wild-type plants (WT) without affecting flower morphology and development. Total BA emitted from flowers of ir-hd20 plants was reduced on average by 60%. This reduction occurred mainly at the late phase of BA emission and it was correlated with 2-fold higher levels of ABA in the corollas of ir-hd20 plants. When a 2-fold decline in ABA corolla levels of these plants was induced by salt stress, BA emissions recovered to WT levels. Supplying ABA to WT flowers either through the cuticle or by pedicle feeding reduced the total BA emissions by 25 to 50%; this reduction occurred primarily at the late phase of emission (similar to the reduction observed in corollas of ir-hd20 plants). Gene expression profiling of corollas collected at 12 pm (six hours before the start of BA emission) revealed that 274 genes changed expression levels significantly in ir-hd20 plants compared to WT. Among these genes, more than 35% were associated with metabolism and the most prominent group was associated with the metabolism of aromatic compounds and phenylpropanoid derivatives. Conclusions The results indicated that regulation of ABA levels in corollas is associated with the late phase of BA emission in N. attenuata plants and that HD20 affects this latter process by mediating changes in both ABA levels and metabolic gene expression. PMID:22548747

  14. Using Genome-Wide SNPs to Detect Structure in High-Diversity and Low-Divergence Populations of Severely Impacted Eastern Tropical Pacific Spinner (Stenella longirostris And Pantropical Spotted Dolphins (S. attenuata

    Directory of Open Access Journals (Sweden)

    Matthew Steven Leslie

    2016-12-01

    Full Text Available Millions of spinner (Stenella longirostris and pantropical spotted dolphins (Stenella attenuata died since the 1960’s as bycatch in tuna nets in the eastern tropical Pacific Ocean. Despite three decades of protection, they show little-to-no sign of recovery (although recent fisheries-independent abundance estimates are not available. In efforts to establish biologically meaningful management boundaries for recovery, endemic subspecies and multiple stocks have been proposed. However, genetic differentiation among most of these units has been difficult to identify, possibly due to low statistical power stemming from large historical abundances, ongoing gene flow, and recent divergence. We tested for genetic structure at multiple hierarchical levels by analyzing the largest dataset to date brought to bear on these questions. Single nucleotide polymorphisms (SNPs were collected from nuclear DNA regions associated with the restriction enzyme site PstI from 72 spinner dolphins and 58 pantropical spotted dolphins using genotype-by-sequencing (GBS. Our results support the current subspecies for both species and indicate stock-level separation for Tres Marias spinner dolphins and the two offshore pantropical spotted dolphin stocks in this area. Although bycatch has been reduced a small fraction of pre-protection levels, incidental mortality continues to impact these populations. Our results are important for the ongoing management and recovery of these highly-impacted pelagic dolphins in the eastern tropical Pacific Ocean.

  15. Revealing complexity and specificity in the activation of lipase-mediated oxylipin biosynthesis: a specific role of the Nicotiana attenuata GLA1 lipase in the activation of jasmonic acid biosynthesis in leaves and roots.

    Science.gov (United States)

    Bonaventure, Gustavo; Schuck, Stefan; Baldwin, Ian T

    2011-09-01

    The activation of enzymatic oxylipin biosynthesis upon wounding, herbivory and pathogen attack depends on the biochemical activation of lipases that make polyunsaturated fatty acids (PUFAs) available to lipoxygenases (LOXs). The identity and number of the lipases involved in this process remain controversial and they probably differ among plant species. Analysis of transgenic Nicotiana attenuata plants (ir-gla1) stably reduced in the expression of the NaGLA1 gene showed that this plastidial glycerolipase is a major supplier of trienoic fatty acids for jasmonic acid (JA) biosynthesis in leaves and roots after wounding and simulated herbivory, but not during infection with the oomycete Phytophthora parasitica (var. nicotianae). NaGLA1 was not essential for the developmental control of JA biosynthesis in flowers and for the biosynthesis of C(6) volatiles by the hydroperoxide lyase (HPL) pathway; however, it affected the metabolism of divinyl ethers (DVEs) early during infection with P. parasitica (var. nicotianae) and the accumulation of NaDES1 and NaLOX1 mRNAs. Profiling of lysolipids by LC-MS/MS was consistent with a rapid activation of NaGLA1 and indicated that this lipase utilizes different lipid classes as substrates. The results revealed the complexity and specificity of the regulation of lipase-mediated oxylipin biosynthesis, highlighting the existence of pathway- and stimulus-specific lipases. © 2011 Blackwell Publishing Ltd.

  16. In vivo phosphorylation of WRKY transcription factor by MAPK.

    Science.gov (United States)

    Ishihama, Nobuaki; Adachi, Hiroaki; Yoshioka, Miki; Yoshioka, Hirofumi

    2014-01-01

    Plants activate signaling networks in response to diverse pathogen-derived signals, facilitating transcriptional reprogramming through mitogen-activated protein kinase (MAPK) cascades. Identification of phosphorylation targets of MAPK and in vivo detection of the phosphorylated substrates are important processes to elucidate the signaling pathway in plant immune responses. We have identified a WRKY transcription factor, which is phosphorylated by defense-related MAPKs, SIPK and WIPK. Recent evidence demonstrated that some group I WRKY transcription factors, which contain a conserved motif in the N-terminal region, are activated by MAPK-dependent phosphorylation. In this chapter, we describe protocols for preparation of anti-phosphopeptide antibodies, detection of activated MAPKs using anti-phospho-MAPK antibody, and activated WRKY using anti-phospho-WRKY antibody, respectively.

  17. Distribución y condiciones ambientales asociadas al comportamiento del delfín bufeo (Tursiops truncatus y el delfín manchado (Stenella attenuata (Cetacea: Delphinidae en el Golfo Dulce, Costa Rica

    Directory of Open Access Journals (Sweden)

    Priscilla Cubero-Pardo

    2007-06-01

    Full Text Available Las características del hábitat que influyen en las especies animales varían de un lugar a otro. Al mismo tiempo, toda especie es rodeada por una serie de factores ambientales que interactúan entre sí, pero la influencia que una característica ambiental particular pueda ejercer sobre una especie depende no sólo de las demás variables, sino de las condiciones morfológicas, fisiológicas y sociales de esa especie. En este estudio, desarrollado de junio 1996 a julio 1997, la pregunta fue enfocada a determinar si comportamientos específicos en el delfín bufeo (Tursiops truncatus y el delfín manchado (Stenella attenuata están relacionados con áreas de distribución y factores ambientales particulares. El área de estudio fue cubierta siguiendo transectos lineares oblicuos predeterminados y cada grupo fue observado de 15 min a 5 h. Las variables ambientales fueron medidas al inicio y al final de cada avistamiento junto con la determinación de la posición geográfica y el comportamiento llevado a cabo por los delfines. Para el bufeo, las actividades de forrajeo/ alimentación mostraron coincidencia exclusiva con bocas de ríos y áreas de coral y manglar, y las actividades sociales y de merodeo, se asociaron a áreas cercanas a los sitios de forrajeo. El desplazamiento ocurrió a lo largo de diferentes puntos paralelos a la costa, con un bajo porcentaje de casos a través del golfo (16.56 %, lo cual sugiere que el bufeo rara vez cruza el golfo. En el caso del manchado, no fue posible asociar zonas comportamientos particulares, pues todo el grupo se mueve junto; sin embargo, si fue observada la presencia de distintos comportamientos en un mismo momento, llevados a cabo por grupos específicos dentro de la manada. Se consideraron factores ambientales tales como la profundidad, la temperatura, la salinidad y la distancia respecto a la costa, entre otros. El ANDEVA de bloques no reveló una relación marcada entre actividades y zonas

  18. Mitogen-activated protein kinase kinase kinase (MAPKKK) 4 from rapeseed (Brassica napus L.) is a novel member inducing ROS accumulation and cell death

    Energy Technology Data Exchange (ETDEWEB)

    Li, Liang, E-mail: 18710470987@163.com; Ye, Chaofei, E-mail: yechaofei001@163.com; Zhao, Rui, E-mail: 571828628@qq.com; Li, Xin, E-mail: 1458272138@qq.com; Liu, Wu-zhen, E-mail: happywuzhenliu@163.com; Wu, Feifei, E-mail: 283915941@qq.com; Yan, Jingli, E-mail: yanjingli512@163.com; Jiang, Yuan-Qing, E-mail: jiangyq@nwafu.edu.cn; Yang, Bo, E-mail: yangwl@nwafu.edu.cn

    2015-11-27

    MAPKKK is the largest family of MAPK cascade, which is known to play important roles in plant growth, development and immune responses. So far, only a few have been functionally characterized even in the model plant, Arabidopsis due to the potential functional redundancy of MAPKKK. We previously identified and cloned a few MAPKKK family genes from rapeseed. In this study, BnaMAPKKK4 was characterized as a member in eliciting accumulation of reactive oxygen species (ROS) and hypersensitive response (HR)-like cell death. This is accompanied with accumulation of malondialdehyde (MDA), anthocyanin as well as nuclear DNA fragmentation. The transcript abundance of a series of ROS accumulation, cell death, and defense response related genes were up-regulated by the expression of MAPKKK4. Further investigation identified BnaMAPKKK4 elicited ROS through the downstream MPK3. These results indicate that BnaMAPKKK4 and its downstream components function in the ROS-induced cell death. - Highlights: • Expression of rapeseed MAPKKK4 induced ROS accumulation and cell death in leaves. • Cell death induced by MAPKKK4 is associated with membrane lipid peroxidation and DNA fragmentation. • MAPKKK4 interacts with MKK5 and MPK3. • MAPKKK4-induced ROS accumulation and cell death require downstream WIPK and SIPK. • MAPKKK4 is a novel MAPKKK modulating ROS accumulation and cell death.

  19. Heart Development in the Spotted Dolphin (Stenella attenuata)

    Czech Academy of Sciences Publication Activity Database

    Míšek, Ivan; Sedmera, D.; Klíma, M.; Thompson, R. P.

    2003-01-01

    Roč. 6, č. 5 (2003), s. 687-699 ISSN 0003-276X R&D Projects: GA AV ČR IAA7039901 Institutional research plan: CEZ:AV0Z5045916 Keywords : cardiac morphogenesis * compact myocardium * coronary vasculogenesis Subject RIV: ED - Physiology Impact factor: 1.587, year: 2002

  20. Benzoylsalicylic acid derivatives as defense activators in tobacco and Arabidopsis.

    Science.gov (United States)

    Kamatham, Samuel; Pallu, Reddanna; Pasupulati, Anil Kumar; Singh, Surya Satyanarayana; Gudipalli, Padmaja

    2017-11-01

    Systemic acquired resistance (SAR) is a long lasting inducible whole plant immunity often induced by either pathogens or chemical elicitors. Salicylic acid (SA) is a known SAR signal against a broad spectrum of pathogens in plants. In a recent study, we have reported that benzoylsalicylic acid (BzSA) is a SAR inducer in tobacco and Arabidopsis plants. Here, we have synthesized BzSA derivatives using SA and benzoyl chlorides of various moieties as substrates. The chemical structures of BzSA derivatives were elucidated using Infrared spectroscopy (IR), Nuclear magnetic spectroscopy (NMR) and High-resolution mass spectrometer (HRMS) analysis. The bioefficacy of BzSA derivatives in inducing defense response against tobacco mosaic virus (TMV) was investigated in tobacco and SA abolished transgenic NahG Arabidopsis plants. Interestingly, pre-treatment of local leaves of tobacco with BzSA derivatives enhanced the expression of SAR genes such as NPR1 [Non-expressor of pathogenesis-related (PR) genes 1], PR and other defense marker genes (HSR203, SIPK, WIPK) in systemic leaves. Pre-treatment of BzSA derivatives reduced the spread of TMV infection to uninfected areas by restricting lesion number and diameter both in local and systemic leaves of tobacco in a dose-dependent manner. Furthermore, pre-treatment of BzSA derivatives in local leaves of SA deficient Arabidopsis NahG plants induced SAR through AtPR1 and AtPR5 gene expression and reduced leaf necrosis and curling symptoms in systemic leaves as compared to BzSA. These results suggest that BzSA derivatives are potent SAR inducers against TMV in tobacco and Arabidopsis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Imposed glutathione-mediated redox switch modulates the tobacco wound-induced protein kinase and salicylic acid-induced protein kinase activation state and impacts on defence against Pseudomonas syringae

    Science.gov (United States)

    Matern, Sanja; Peskan-Berghoefer, Tatjana; Gromes, Roland; Kiesel, Rebecca Vazquez; Rausch, Thomas

    2015-01-01

    The role of the redox-active tripeptide glutathione in plant defence against pathogens has been studied extensively; however, the impact of changes in cellular glutathione redox potential on signalling processes during defence reactions has remained elusive. This study explored the impact of elevated glutathione content on the cytosolic redox potential and on early defence signalling at the level of mitogen-activated protein kinases (MAPKs), as well as on subsequent defence reactions, including changes in salicylic acid (SA) content, pathogenesis-related gene expression, callose depositions, and the hypersensitive response. Wild-type (WT) Nicotiana tabacum L. and transgenic high-glutathione lines (HGL) were transformed with the cytosol-targeted sensor GRX1-roGFP2 to monitor the cytosolic redox state. Surprisingly, HGLs displayed an oxidative shift in their cytosolic redox potential and an activation of the tobacco MAPKs wound-induced protein kinase (WIPK) and SA-induced protein kinase (SIPK). This activation occurred in the absence of any change in free SA content, but was accompanied by constitutively increased expression of several defence genes. Similarly, rapid activation of MAPKs could be induced in WT tobacco by exposure to either reduced or oxidized glutathione. When HGL plants were challenged with adapted or non-adapted Pseudomonas syringae pathovars, the cytosolic redox shift was further amplified and the defence response was markedly increased, showing a priming effect for SA and callose; however, the initial and transient hyperactivation of MAPK signalling was attenuated in HGLs. The results suggest that, in tobacco, MAPK and SA signalling may operate independently, both possibly being modulated by the glutathione redox potential. Possible mechanisms for redox-mediated MAPK activation are discussed. PMID:25628332

  2. Isomers of green leaf volatiles in Nicotiana attenuata and their role in plant-insect interactions

    NARCIS (Netherlands)

    Allmann, S.

    2012-01-01

    Omdat planten blootgesteld kunnen worden aan aanvallen van schadelijke insecten, hebben ze geavanceerde verdedigingssystemen ontwikkeld. Een belangrijke verdedigingsstrategie is de afgifte van geurstoffen die natuurlijke vijanden van het schadelijke insect aantrekken. Dit is een voorbeeld van een

  3. The Sesquiterpenes(E)-?-Farnesene and (E)-?-Bergamotene Quench Ozone but Fail to Protect the Wild Tobacco Nicotiana attenuata from Ozone, UVB, and Drought Stresses

    OpenAIRE

    Palmer-Young, Evan C.; Daniel Veit; Jonathan Gershenzon; Schuman, Meredith C

    2015-01-01

    Among the terpenes, isoprene (C5) and monoterpene hydrocarbons (C10) have been shown to ameliorate abiotic stress in a number of plant species via two proposed mechanisms: membrane stabilization and direct antioxidant effects. Sesquiterpene hydrocarbons (C15) not only share the structural properties thought to lend protective qualities to isoprene and monoterpene hydrocarbons, but also react rapidly with ozone, suggesting that sesquiterpenes may similarly enhance tolerance of abiotic stresses...

  4. Development of immature tiger-fly Coenosia attenuata (Stein) reared on larvae of the fungus gnat Bradysia impatiens (Johannsen) in coir substrate

    Science.gov (United States)

    The ability to rear a beneficial predatory insect is often required for its use in inoculative releases for classical biological control applications. However, affordable mass production is required before a beneficial predatory insect will be commercialized for large scale repetitive releases. The...

  5. A Nicotiana attenuata cell wall invertase inhibitor (NaCWII) reduces growth and increases secondary metabolite biosynthesis in herbivore‐attacked plants

    National Research Council Canada - National Science Library

    Ferrieri, Abigail P; Arce, Carla C. M; Machado, Ricardo A. R; Meza‐Canales, Ivan D; Lima, Eraldo; Baldwin, Ian T; Erb, Matthias

    2015-01-01

    ... . To understand the role of Na CWII in planta , we silenced its expression by RNA interference and measured changes in primary and secondary metabolism and plant growth following simulated herbivory. Na CWII...

  6. 77 FR 21539 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Sturgeon Research in the...

    Science.gov (United States)

    2012-04-10

    ... truncatus), Atlantic spotted dolphins (Stenella frontalis), pantropical spotted dolphins (S. attenuata), and striped dolphins (S. coeruleoalba). Specified Activities The USFWS is working with NMFS, the U.S...

  7. 76 FR 23570 - Incidental Taking of Marine Mammals; Taking of Marine Mammals Incidental to the Explosive Removal...

    Science.gov (United States)

    2011-04-27

    ...), Atlantic spotted dolphins (Stenella frontalis), pantropical spotted dolphins (Stenella attenuata), Clymene dolphins (Stenella clymene), striped dolphins (Stenella coeruleoalba), spinner dolphins (Stenella...

  8. 77 FR 33443 - Marine Mammals; File No. 16473

    Science.gov (United States)

    2012-06-06

    ... spotted (Stenella frontalis), Risso's (Grampus griseus), Fraser's (Lagenodelphis hosei), rough-toothed (Steno bredanensis), pantropical spotted (S. attenuata), striped (S. coeruleoalba), clymene (S. clymene...

  9. Distribución y condiciones ambientales asociadas al comportamiento del delfín bufeo (Tursiops truncatus) y el delfín manchado (Stenella attenuata) (Cetacea: Delphinidae) en el Golfo Dulce, Costa Rica

    OpenAIRE

    Priscilla Cubero-Pardo

    2007-01-01

    Las características del hábitat que influyen en las especies animales varían de un lugar a otro. Al mismo tiempo, toda especie es rodeada por una serie de factores ambientales que interactúan entre sí, pero la influencia que una característica ambiental particular pueda ejercer sobre una especie depende no sólo de las demás variables, sino de las condiciones morfológicas, fisiológicas y sociales de esa especie. En este estudio, desarrollado de junio 1996 a julio 1997, la pregunta fue enfocada...

  10. Insights into the diet of a poorly known species: pygmy killer whale ...

    African Journals Online (AJOL)

    Despite having a worldwide distribution in tropical waters, knowledge on pygmy killer whales Feresa attenuata, including diet, is poor, with only a few studies carried out to date. The presence of otoliths and beaks in stomachs that have been examined indicate that the diet of F. attenuata includes squid, octopus and fish.

  11. Role of brassinosteroid signaling in modulating Tobacco mosaic virus resistance in Nicotiana benthamiana

    Science.gov (United States)

    Deng, Xing-Guang; Zhu, Tong; Peng, Xing-Ji; Xi, De-Hui; Guo, Hongqing; Yin, Yanhai; Zhang, Da-Wei; Lin, Hong-Hui

    2016-01-01

    Plant steroid hormones, brassinosteroids (BRs), play essential roles in plant growth, development and stress responses. However, mechanisms by which BRs interfere with plant resistance to virus remain largely unclear. In this study, we used pharmacological and genetic approaches in combination with infection experiments to investigate the role of BRs in plant defense against Tobacco Mosaic Virus (TMV) in Nicotiana benthamiana. Exogenous applied BRs enhanced plant resistance to virus infection, while application of Bikinin (inhibitor of glycogen synthase kinase-3), which activated BR signaling, increased virus susceptibility. Silencing of NbBRI1 and NbBSK1 blocked BR-induced TMV resistance, and silencing of NbBES1/BZR1 blocked Bikinin-reduced TMV resistance. Silencing of NbMEK2, NbSIPK and NbRBOHB all compromised BR-induced virus resistance and defense-associated genes expression. Furthermore, we found MEK2-SIPK cascade activated while BES1/BZR1 inhibited RBOHB-dependent ROS production, defense gene expression and virus resistance induced by BRs. Thus, our results revealed BR signaling had two opposite effects on viral defense response. On the one hand, BRs enhanced virus resistance through MEK2-SIPK cascade and RBOHB-dependent ROS burst. On the other hand, BES1/BZR1 inhibited RBOHB-dependent ROS production and acted as an important mediator of the trade-off between growth and immunity in BR signaling. PMID:26838475

  12. Nucleocytoplasmic partitioning of tobacco N receptor is modulated by SGT1.

    Science.gov (United States)

    Hoser, Rafał; Zurczak, Marek; Lichocka, Małgorzata; Zuzga, Sabina; Dadlez, Michal; Samuel, Marcus A; Ellis, Brian E; Stuttmann, Johannes; Parker, Jane E; Hennig, Jacek; Krzymowska, Magdalena

    2013-10-01

    SGT1 (Suppressor of G2 allele of SKP1) is required to maintain plant disease Resistance (R) proteins with Nucleotide-Binding (NB) and Leucine-Rich Repeat (LRR) domains in an inactive but signaling-competent state. SGT1 is an integral component of a multi-protein network that includes RACK1, Rac1, RAR1, Rboh, HSP90 and HSP70, and in rice the Mitogen-Activated Protein Kinase (MAPK), OsMAPK6. Tobacco (Nicotiana tabacum) N protein, which belongs to the Toll-Interleukin Receptor (TIR)-NB-LRR class of R proteins, confers resistance to Tobacco Mosaic Virus (TMV). Following transient expression in planta, we analyzed the functional relationship between SGT1, SIPK - a tobacco MAPK6 ortholog - and N, using mass spectrometry, confocal microscopy and pathogen assays. Here, we show that tobacco SGT1 undergoes specific phosphorylation in a canonical MAPK target-motif by SIPK. Mutation of this motif to mimic SIPK phosphorylation leads to an increased proportion of cells displaying SGT1 nuclear accumulation and impairs N-mediated resistance to TMV, as does phospho-null substitution at the same residue. Forced nuclear localization of SGT1 causes N to be confined to nuclei. Our data suggest that one mode of regulating nucleocytoplasmic partitioning of R proteins is by maintaining appropriate levels of SGT1 phosphorylation catalyzed by plant MAPK. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  13. Effect of seismic operations on cetaceans sightings off-shore Akwa ...

    African Journals Online (AJOL)

    66.78%) sightings of whales and 94 (33.22%) sightings of dolphins. Four species of cetaceans were identified, bottlenose dolphins (Tursiops truncatus) were the most abundant followed by pantropical spotted dolphins (Stenella attenuata).

  14. A new Maculotriton

    NARCIS (Netherlands)

    Bayer, Ch.

    1933-01-01

    Drupa (Maculotriton) buitendijki n. sp. (Pl. I, fig. 1). Testa parvula, tenuis, elongato-turrita, nitidula. Anfractus 10, apice laevi anfractibus 3l/2 annumerata, liris subtilimis, longitudinalibus et transversis ad decussationem nodulosis reticulata Varices 10. Apertura ovata, utrinque attenuata,

  15. F-15E Beddown at Seymour Johnson AFB, North Carolina

    Science.gov (United States)

    1988-03-01

    forficatus) "* Carolina lilaeopsis ( Lilaeopsis carolinensis) "* Sensitive joint-vetch (Aeschvnomene virainica) "* Pine barrens treefrog (Hyla andersonii...tomentos) SRS Carolina Lilaeopsis ( Lilaeopsis carolinensis T (=L. attenuata)) Southern Twayblade (Listera australis) SRS Winged Seedbox (Ludwigia alata

  16. 76 FR 35856 - Incidental Taking of Marine Mammals; Taking of Marine Mammals Incidental to the Explosive Removal...

    Science.gov (United States)

    2011-06-20

    ... during EROS activities are bottlenose dolphins (Tursiops truncatus), Atlantic spotted dolphins (Stenella frontalis), pantropical spotted dolphins (Stenella attenuata), Clymene dolphins (Stenella clymene), striped dolphins (Stenella coeruleoalba), spinner dolphins (Stenella longirostris), rough-toothed dolphins (Steno...

  17. 76 FR 76950 - Marine Mammals; File No. 16473

    Science.gov (United States)

    2011-12-09

    ... bottlenose (Tursiops truncatus), 5,000 Atlantic spotted (Stenella frontalis), 2,500 Risso's (Grampus griseus... (S. attenuata), 500 striped (S. coeruleoalba), 250 clymene (S. clymene), 100 spinner (S. longirostris...

  18. 50 CFR 218.21 - Permissible methods of taking.

    Science.gov (United States)

    2010-10-01

    ... (Stenella attenuata)—100 (an average of 20 annually); (iii) Clymene dolphin (S. clymene)—150 (an average of...) Striped dolphin (S. coeruleoalba)—100 (an average of 20 annually); (vi) Spinner dolphin (S. longirostris...

  19. 50 CFR 218.11 - Permissible methods of taking.

    Science.gov (United States)

    2010-10-01

    ... dolphin (Stenella attenuata)—100 (an average of 20 annually); (iii) Clymene dolphin (S. clymene)—100 (an...) Striped dolphin (S. coeruleoalba)—100 (an average of 20 annually); (vi) Risso's dolphin (Grampus griseus...

  20. 78 FR 40698 - Takes of Marine Mammals Incidental to Specified Activities; Office of Naval Research Acoustic...

    Science.gov (United States)

    2013-07-08

    ... macrorhynchus. Sperm Whale Physeter macrocephalus.... Endangered/Depleted. Spinner Dolphin Stenella longirostris. Stejneger's Beaked Whale Mesoplodon stejnegeri. Striped Dolphin Stenella coeruleoalba. Pinnipeds Hawaiian.... Pacific White-sided Dolphin Lagenorhynchus obliquidens. Pantropical Spotted Dolphin Stenella attenuata...

  1. Dos especies nuevas de calathea (Marantaceae) de la Amozonia Colombiana

    OpenAIRE

    Suárez Stella; Galeano Gloria

    2000-01-01

    Two new species of Marantaceae from Amazonian Colombia are described and illustrated: Calathea caquetensis and C. compacta. C. caquetensis is apparently related to C. attenuata and C. silvosa. C. compacta seems to be related to C. ecuminata, C. pearcei and C. schunkei.Se describen e ilustran dos especies nuevas de Marantaceae de la Amazonia colombiana: Calathea caquetensís y C. compacta. C. caquetensis está aparentemente relacionada con C. attenuata y C. silvosa. C compacta parece estar relac...

  2. Dos especies nuevas de calathea (Marantaceae de la Amozonia Colombiana

    Directory of Open Access Journals (Sweden)

    Suárez Stella

    2000-07-01

    Full Text Available Two new species of Marantaceae from Amazonian Colombia are described and illustrated: Calathea caquetensis and C. compacta. C. caquetensis is apparently related to C. attenuata and C. silvosa. C. compacta seems to be related to C. ecuminata, C. pearcei and C. schunkei.Se describen e ilustran dos especies nuevas de Marantaceae de la Amazonia colombiana: Calathea caquetensís y C. compacta. C. caquetensis está aparentemente relacionada con C. attenuata y C. silvosa. C compacta parece estar relacionada con C. acuminata, C. pearcei y C. schunkei.

  3. Untitled

    Indian Academy of Sciences (India)

    of male and female gametophytes, endosperm and embryo development in. Cryptostegia grandiflora and Caralluma attenuata. Biswas (1957) studied the embryology of Daemia extensa. MATERIALS AND METHODs. The material of Hemidesmus indicus was collected at Tirupati hills,. Cynanchun callialata at Anantagiri ...

  4. AcEST: BP919922 [AcEST

    Lifescience Database Archive (English)

    Full Text Available =Bambusa oldhamii ... 59 2e-07 tr|Q5IA15|Q5IA15_AGAAE Ribosomal protein S1 (Fragment) OS=Agave ... 59 2e-07 ...4 STKT 23 T+T Sbjct: 208 QTRT 211 >tr|Q5IA15|Q5IA15_AGAAE Ribosomal protein S1 (Fragment) OS=Agave attenuata

  5. A new species of Roupala (proteaceae) in Suriname

    NARCIS (Netherlands)

    Mennega, Alberta M.W.

    1967-01-01

    Arbor 8 m alta, altitudine pectoris 20 cm diam.; ramuli teretes, glabri. Folia coriacea, glabra, plana, late elliptica vel late obovata, apice obtusa, rotundata vel subacuminata, basi attenuata et in petiolum decurrentia, 9-12 cm longa, 5-7½ cm lata, statu sicco supra viridia, leviter nitida, infra

  6. Ectoparasites from the South American sea lion (Otaria flavescens from Peruvian coast

    Directory of Open Access Journals (Sweden)

    Luis A. Gomez-Puerta

    2015-10-01

    Full Text Available Two species of ectoparasites were collected from a South American sea lion (Otaria flavescens found stranded on the beaches of Chorrillos in Lima, Peru. The ectoparasites were identified as Antarctophthirus microchir (Phthiraptera and Orthohalarachne attenuata (Acari. Some morphological characteristics are described in this report. The finding of these ectoparasites is the first records in Peru.

  7. A new species of Medinilla (Melastomataceae) from Sumatra and notes on allied species

    NARCIS (Netherlands)

    Nayar, M.P.

    1970-01-01

    Frutex. Ramis junioribus subangulatis, puberubs, vetustioribus teretibus glabratis. Folia opposita, elliptico-lanceolata, 6—10 cm longa, 1.5—2.8 cm lata, basi cuneata, apice longe acuminato-attenuata, margine integra, supra glabra, subtus minute puberula, 3-nervia, venulis transversis indistinctis,

  8. Bombesin-like immunoreactivity in the nervous system of hydra

    DEFF Research Database (Denmark)

    Grimmelikhuijzen, C J; Dockray, G J; Yanaihara, N

    1981-01-01

    With immunocytochemical methods, nerve cells have been detected in Hydra attenuata containing bombesin-like immunoreactivity. These nerve cells are located in ectoderm of all body regions of the animal and are especially abundant in basal disk and tentacles. Radioimmunoassay of extracts of hydra ...

  9. Relationship between sea surface temperatures and dolphin-associated fishing activities by the Mexican tuna fleet

    OpenAIRE

    Gomez-Muñoz, V.M.

    1992-01-01

    Data from the Mexican purse seiner fleet operating in the eastern Tropical Pacific, for the year 1985-1990, are used to show that the fraction of surface schools of yellowfin tuna Thunnus albacares associated with dolphins (Stenella attenuata and others) increases with sea surface temperature. Possible reasons for this correlation are briefly discussed.

  10. New xenophytes from Gran Canaria (Canary Islands, Spain), with emphasis on naturalized and (potentially) invasive species

    OpenAIRE

    Verloove, F.

    2013-01-01

    Trabajos recientes de campo en Gran Canaria han facilitado el descubrimiento de nuevas localidades para plantas vasculares no nativas. Agave attenuata, Antigonon leptopus, Atriplex nummularia, Cascabela thevetia, Cenchrus echinatus, Cuscuta campestris, Diplachne fusca subsp. uninervia, Diplotaxis tenuifolia, Dysphania anthelmintica (hasta ahora confundida con D. ambrosioides), Eclipta prostrata, Euphorbia pulcherrima, Fagopyrum esculentum, Gossypium barbadense, Lablab purpureus, Lemna minuta,...

  11. 75 FR 49465 - Marine Mammals; File No. 14682

    Science.gov (United States)

    2010-08-13

    ... determine aspects of the behavior and use of the acoustic environment by large whales, and to determine the... whale (Ziphius cavirostris), killer whale (Orcinus orca), humpback whale (Megaptera novaeangliae), dwarf... macrorhynchus), false killer whale (Pseudorca crassidens), pygmy killer whale (Feresa attenuata), melon- headed...

  12. In vitro shoot multiplication and conservation of Caralluma ...

    African Journals Online (AJOL)

    Jane

    2011-03-30

    Mar 30, 2011 ... Venkatesh S, Reddy GD, Reddy BM, Ramesh M, Rao AVNA (2003). Antihyperglycemic activity of Caralluma attenuata. Fitoterapia, 74: 274-279. Wadood A, Wadood N, Shah SA (1989). Effects of Acacia arabica and. Caralluma edulis on blood glucose levels of normal and alloxan diabetic rabbits. J. Pak.

  13. Browse Title Index - African Journals Online

    African Journals Online (AJOL)

    Items 501 - 550 of 1027 ... Vol 37, No 3 (2015), Insights into the diet of a poorly known species: pygmy killer whale Feresa attenuata from Cape Verde, West Africa, Abstract ... Vol 19 (1998), Investigation on the effects of different levels of effort and of the closed season in the jig fishery for chokka squid loligo vulgaris reynaudii ...

  14. 50 CFR 216.242 - Permissible methods of taking.

    Science.gov (United States)

    2010-10-01

    ...). (J) Striped dolphin (Stenella coeruleoalba)—873620 (an average of 174274 annually). (K) Common... (Stenella attenuata)—696530 (an average of 139306 annually). (G) Atlantic spotted dolphin (Stenella frontalis)—1881805 (an average of 376361 annually). (H) Spinner dolphin (Stenella longirostris)—105775 (an...

  15. 50 CFR 218.181 - Permissible methods of taking.

    Science.gov (United States)

    2010-10-01

    ... (Stenella frontalis)—2,355 (an average of 471 annually); (v) Pantropical spotted dolphin (S. attenuata)—115 (an average of 23 annually); (vi) Striped dolphin (S. coeruleoalba)—25 (an average of 5 annually...) Atlantic spotted dolphin (Stenella frontalis)—10 (an average of 2 annually); (iii) Pantropical spotted...

  16. 50 CFR 216.272 - Permissible methods of taking.

    Science.gov (United States)

    2010-10-01

    ... 1516 annually) (J) Pan-tropical spotted dolphin (Stenella attenuata)—100 (an average of 20 annually) (K) Spinner dolphin (Stenella longirostris)—100 (an average of 20 annually) (L) Striped dolphin (Stenella coeruleoalba)—9190 (an average of 1838 annually) (M) Long-beaked common dolphin (Delphinus capensis)—23145 (an...

  17. 50 CFR 218.102 - Permissible methods of taking.

    Science.gov (United States)

    2010-10-01

    ... (an average of 1,289 annually); (L) Striped dolphin (Stenella coeruleoalba)—44,290 (an average of 8... average of 4,615 annually); (Q) Pantropical spotted dolphin (Stenella attenuata)—162,495 (an average of 32...) Spinner dolphin (Stenella longirostris)—10,720 (an average of 2,144 annually); and (T) Unidentified...

  18. Nitric oxide and salicylic acid signaling in plant defense

    Science.gov (United States)

    Klessig, Daniel F.; Durner, Jörg; Noad, Robert; Navarre, Duroy A.; Wendehenne, David; Kumar, Dhirendra; Zhou, Jun Ma; Shah, Jyoti; Zhang, Shuqun; Kachroo, Pradeep; Trifa, Youssef; Pontier, Dominique; Lam, Eric; Silva, Herman

    2000-01-01

    Salicylic acid (SA) plays a critical signaling role in the activation of plant defense responses after pathogen attack. We have identified several potential components of the SA signaling pathway, including (i) the H2O2-scavenging enzymes catalase and ascorbate peroxidase, (ii) a high affinity SA-binding protein (SABP2), (iii) a SA-inducible protein kinase (SIPK), (iv) NPR1, an ankyrin repeat-containing protein that exhibits limited homology to IκBα and is required for SA signaling, and (v) members of the TGA/OBF family of bZIP transcription factors. These bZIP factors physically interact with NPR1 and bind the SA-responsive element in promoters of several defense genes, such as the pathogenesis-related 1 gene (PR-1). Recent studies have demonstrated that nitric oxide (NO) is another signal that activates defense responses after pathogen attack. NO has been shown to play a critical role in the activation of innate immune and inflammatory responses in animals. Increases in NO synthase (NOS)-like activity occurred in resistant but not susceptible tobacco after infection with tobacco mosaic virus. Here we demonstrate that this increase in activity participates in PR-1 gene induction. Two signaling molecules, cGMP and cyclic ADP ribose (cADPR), which function downstream of NO in animals, also appear to mediate plant defense gene activation (e.g., PR-1). Additionally, NO may activate PR-1 expression via an NO-dependent, cADPR-independent pathway. Several targets of NO in animals, including guanylate cyclase, aconitase, and mitogen-activated protein kinases (e.g., SIPK), are also modulated by NO in plants. Thus, at least portions of NO signaling pathways appear to be shared between plants and animals. PMID:10922045

  19. Antarctic sponges (Porifera, Demospongiae of the South Shetland Islands and vicinity: part I. Spirophorida, Astrophorida, Hadromerida, Halichondrida and Haplosclerida Esponjas Antárticas (Porifera, Demospongiae das Ilhas Shetland do Sul e áreas próximas: parte I. Spirophorida, Astrophorida, Hadromerida, Halichondrida e Haplosclerida

    Directory of Open Access Journals (Sweden)

    Maurício Campos

    2007-01-01

    Full Text Available The aim of this work is to redescribe 11 species of sponges collected through the Brazilian Antarctic Program (PROANTAR, at the South Shetland Islands and vicinity. New information is provided on the Antarctic sponge fauna, in regard to species richness and the geographical and bathymetric distributions of identified species. The following species were identified and are here illustrated and fully described: Cinachyra antarctica (Carter, 1872, Cinachyra barbata Sollas, 1886, Craniella leptoderma (Sollas, 1886, Tethyopsis longispinum (Lendenfeld, 1907, Polymastia invaginata Kirkpatrick, 1907, Homaxinella balfourensis (Ridley & Dendy, 1886, Suberites montiniger Carter, 1880, Halichondria (Eumastia attenuata (Topsent, 1915, Haliclona (Soestella chilensis (Thiele, 1905, Hemigellius bidens (Topsent, 1901 and Calyx arcuarius (Topsent, 1913. Two new records are given for the Antarctic continent: Halichondria (Eumastia attenuata (Topsent, 1915 and Haliclona (Soestella chilensis (Thiele, 1905. Tethyopsis longispinum (Lendenfeld, 1907, Suberites montiniger Carter, 1880 and Hemigellius bidens (Topsent, 1901 represent the first records for this sector of the continent. Bathymetric data are extended for T. longispinum and H. attenuata.O objetivo deste trabalho é redescrever 11 espécies de esponjas coletadas através do Programa Antártico Brasileiro (PROANTAR, nas Is. Shetland do Sul e áreas próximas. Nnovas informações são fornecidas acerca do conhecimento da fauna de poríferos da Antártica, tanto para a riqueza específica como para os dados referentes às distribuições geográfica e batimétrica das espécies identificadas. As seguintes espécies foram identificadas e são aqui ilustradas e amplamente descritas: Cinachyra antarctica (Carter, 1872, Cinachyra barbata Sollas, 1886, Craniella leptoderma (Sollas, 1886, Tethyopsis longispinum (Lendenfeld, 1907, Polymastia invaginata Kirkpatrick, 1907, Homaxinella balfourensis (Ridley & Dendy, 1886

  20. AFLP analysis and zebra disease resistance identification of 40 sisal genotypes in China.

    Science.gov (United States)

    Gao, Jianming; Luoping; Guo, Chaoming; Li, Jinzhi; Liu, Qiaolian; Chen, Helong; Zhang, Shiqing; Zheng, Jinlong; Jiang, Chenji; Dai, Zhenzhen; Yi, Kexian

    2012-05-01

    Sisal is the most important fiber crop in tropical and subtropical areas in China and the world. Zebra disease is a serious threat to the main cultivar Agave hybrid No.11648 (H.11648) worldwide. To select germplasm materials with zebra disease resistance for breeding, the fluorescent amplified fragment length polymorphism (AFLP) technique was used to make a cluster analysis of the genetic relationships of 40 sisal genotypes grown in China, and Phytophthora nicotianae was used to inoculate the 40 genotypes to identify their resistance to zebra disease. As a result, the similarity coefficient among 40 sisal genotypes was found to be 0.44-0.83 and the 40 genotypes show different levels of disease resistance. According to the AFLP analysis, the disease resistance and chromosomal ploidy, it can be reasoned that, A. attenuata var. marginata, Dong 109, Nan ya 1 and A. attenuata are suitable for hybridization with H.11648 to breed a new disease-resistant variety.

  1. Four New Records of Holaxonia (Anthozoa: Octocorallia: Alcyonacea from Korea

    Directory of Open Access Journals (Sweden)

    Kim, Min-Sun

    2014-04-01

    Full Text Available The four species of the suborder Holaxonia, Anthogorgia japonica Studer, 1889 of family Acanthogorgiidae, Astrogorgia rubra (Thomson & Henderson, 1906, Euplexaura attenuata (Nutting, 1910, and E. erecta (Kukenthal, 1908 of family Plexauridae have been newly recorded in Korea. They were collected from intertidal and sublittoral zones in the western and southern coasts and Jeju-do Island of Korea by SCUBA diving and fishing nets from 1969 to 2010. This study approaches holaxonians by focusing on external and internal morphologies including size, form, and color of colonies, branches, polyps, coenenchyme, axis, and spicules. Anthogorgia japonica is characterized by its planar growth form, dichotomously branched form, non-retractile polyps, and Astrogorgia rubra by arrangement of calyxes being situated in lateral side at stems and alternately in all sides at branches. Euplexaura attenuata is sparsely and laterally branched colony, and has straight wand-like stems. Euplexaura erecta has branches which run parallel to the main stem.

  2. Aquatic ecotoxicity assessment of a new natural formicide.

    Science.gov (United States)

    Testolin, Renan C; Tischer, Vinícius; Lima, Andre O S; Cotelle, Sylvie; Férard, Jean-François; Radetski, Claudemir M

    2012-07-01

    Agrochemicals could reach aquatic ecosystems and damage ecosystem functionality. Natural formicide could be an alternative to use in comparison with the more toxic formicides available on the market. Thus, the objective of this study was to assess the ecotoxicity of the new natural formicide Macex® with a battery of classical aquatic ecotoxicity tests. Bacteria (Aliivibrio fischeri), algae (Pseudokirchneriella subcapitata), hydra (Hydra attenuata), daphnids (Daphnia magna), and fish (Danio rerio) tests were performed in accordance with international standardized methodologies. In the range of formicide concentrations tested (0.03 to 2.0 g L(-1)) EC(50) values varied from 0.49 to >2.0 g L(-1), with P. subcapitata being the most sensitive species and H. attenuata and D. rerio the most tolerant species to this product in aqueous solutions. This new formicide preparation can be classed as a product of low toxicity compared to the aquatic ecotoxicity of the most common commercialized formicides.

  3. Study of the Oriental genus Alishania Vilbaste (Hemiptera: Cicadellidae: Deltocephalinae) from China with description of one new species.

    Science.gov (United States)

    Lu, Lin; Zhang, Yalin

    2016-11-23

    The Oriental leafhopper genus Alishania Vilbaste, is reviewed and includes A. formosana, A. fodingensis, A. attenuata and a new species, A. quadrilamina sp. nov., found during a survey of leafhoppers in Xizang and described here. A key to males of Alishania species, together with descriptions, a checklist and figures are provided. Based on the structure of the aedeagus, Alishania is here transferred from subtribe Opsiina to subtribe Circuliferina of tribe Opsiini.

  4. African Journal of Marine Science - Vol 37, No 3 (2015)

    African Journals Online (AJOL)

    Insights into the diet of a poorly known species: pygmy killer whale Feresa attenuata from Cape Verde, West Africa · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. P.R. O'Dwyer, S Berrow, P López-Suárez, C.O. Lamao, 427-430. http://dx.doi.org/10.2989/1814232X.

  5. Movements and Spatial Use of Odontocetes in the Western Main Hawaiian Islands: Results of a Three-Year Study Off Oahu and Kauai

    Science.gov (United States)

    2013-11-08

    group size, location, and behavior of all odontocetes encountered. Species encountered infrequently (e.g., false killer whales , and pygmy killer ...on five species: pygmy killer whales , false killer whales , bottlenose dolphins, rough-toothed dolphins, and short-finned pilot whales . For all five...6.5 cm) darts, depending on species (e.g., short darts for pygmy killer whales [Feresa attenuata], rough-toothed, and bottlenose dolphins, long

  6. Evaluacion preliminar de toxicidad, genotoxicidad y actividad antimicrobiana de Sida rhombifolia L

    National Research Council Canada - National Science Library

    Bruges, Keile; Reguero Reza, Maria Teresa

    2007-01-01

    ... la planta Sida rhombifolia L. a la cual se le realizo la evaluacion de la toxicidad de extractos y fracciones utilizando como organismos de prueba Daphnia magna, Hydra attenuata y Artemia salina. La actividad biologica fue evaluada mediante la prueba de sensibilidad a antimicrobianos y la genotoxicidad con el ensayo Cometa. Los ensayos de toxicidad aguda con los organismos de prueba muestran que los extractos acuosos son practicamente no toxicos (C[L.sub.50] >1000 ppm), lo cual sugiere que su us...

  7. Native bacterial endophytes promote host growth in a species-specific manner; phytohormone manipulations do not result in common growth responses.

    Science.gov (United States)

    Long, Hoang Hoa; Schmidt, Dominik D; Baldwin, Ian T

    2008-07-16

    All plants in nature harbor a diverse community of endophytic bacteria which can positively affect host plant growth. Changes in plant growth frequently reflect alterations in phytohormone homoeostasis by plant-growth-promoting (PGP) rhizobacteria which can decrease ethylene (ET) levels enzymatically by 1-aminocyclopropane-1-carboxylate (ACC) deaminase or produce indole acetic acid (IAA). Whether these common PGP mechanisms work similarly for different plant species has not been rigorously tested. We isolated bacterial endophytes from field-grown Solanum nigrum; characterized PGP traits (ACC deaminase activity, IAA production, phosphate solubilization and seedling colonization); and determined their effects on their host, S. nigrum, as well as on another Solanaceous native plant, Nicotiana attenuata. In S. nigrum, a majority of isolates that promoted root growth were associated with ACC deaminase activity and IAA production. However, in N. attenuata, IAA but not ACC deaminase activity was associated with root growth. Inoculating N. attenuata and S. nigrum with known PGP bacteria from a culture collection (DSMZ) reinforced the conclusion that the PGP effects are not highly conserved. We conclude that natural endophytic bacteria with PGP traits do not have general and predictable effects on the growth and fitness of all host plants, although the underlying mechanisms are conserved.

  8. Native bacterial endophytes promote host growth in a species-specific manner; phytohormone manipulations do not result in common growth responses.

    Directory of Open Access Journals (Sweden)

    Hoang Hoa Long

    Full Text Available BACKGROUND: All plants in nature harbor a diverse community of endophytic bacteria which can positively affect host plant growth. Changes in plant growth frequently reflect alterations in phytohormone homoeostasis by plant-growth-promoting (PGP rhizobacteria which can decrease ethylene (ET levels enzymatically by 1-aminocyclopropane-1-carboxylate (ACC deaminase or produce indole acetic acid (IAA. Whether these common PGP mechanisms work similarly for different plant species has not been rigorously tested. METHODOLOGY/PRINCIPAL FINDINGS: We isolated bacterial endophytes from field-grown Solanum nigrum; characterized PGP traits (ACC deaminase activity, IAA production, phosphate solubilization and seedling colonization; and determined their effects on their host, S. nigrum, as well as on another Solanaceous native plant, Nicotiana attenuata. In S. nigrum, a majority of isolates that promoted root growth were associated with ACC deaminase activity and IAA production. However, in N. attenuata, IAA but not ACC deaminase activity was associated with root growth. Inoculating N. attenuata and S. nigrum with known PGP bacteria from a culture collection (DSMZ reinforced the conclusion that the PGP effects are not highly conserved. CONCLUSIONS/SIGNIFICANCE: We conclude that natural endophytic bacteria with PGP traits do not have general and predictable effects on the growth and fitness of all host plants, although the underlying mechanisms are conserved.

  9. Two MAPK cascades, NPR1, and TGA transcription factors play a role in Pto-mediated disease resistance in tomato.

    Science.gov (United States)

    Ekengren, Sophia K; Liu, Yule; Schiff, Michael; Dinesh-Kumar, S P; Martin, Gregory B

    2003-12-01

    The tomato Pto kinase confers resistance to the causative agent of bacterial speck disease, Pseudomonas syringae pv. tomato, by recognizing the pathogen effector proteins AvrPto or AvrPtoB. Pto-mediated resistance requires multiple signal transduction pathways and has been shown to activate many defense responses including an oxidative burst, rapid changes in the expression of over 400 genes, and localized cell death. We have tested the role in Pto-mediated resistance in tomato of a set of 21 genes from other species known to be involved in defense-related signaling. Expression of each gene was suppressed by virus-induced gene silencing (VIGS) and the effect on disease symptoms and bacterial growth during the tomato-Pseudomonas incompatible interaction was determined. We found that Pto-mediated resistance was compromised by silencing of genes encoding two mitogen-activated protein (MAP) kinase kinases, MEK1 and MEK2, two MAP kinases, NTF6 and wound-induced protein kinase (WIPK), a key regulator of systemic acquired resistance (SAR), NPR1, and two transcription factors, TGA1a and TGA2.2. A lesser impact on Pto-mediated resistance was observed in plants silenced for RAR1 and COI1. The identification of nine genes that play a role in resistance to bacterial speck disease both advances our knowledge of Pto signal transduction and demonstrates the conservation of many defense signaling components among diverse plant species.

  10. The aquatic impact of ionic liquids on freshwater organisms.

    Science.gov (United States)

    Costa, Susana P F; Pinto, Paula C A G; Saraiva, M Lúcia M F S; Rocha, Fábio R P; Santos, Joyce R P; Monteiro, Regina T R

    2015-11-01

    Ionic liquids (ILs), also known as liquid electrolytes, are powerful solvents with a wide variety of academic and industrial applications. Bioassays with aquatic organisms constitute an effective tool for the evaluation of ILs' toxicity, as well as for the prediction and identification of possible moieties that act as toxicophores. In this work, the acute toxicity of six ILs and two commonly used organic solvents was evaluated using freshwater organisms: Daphnia magna, Raphidocelis subcapitata and Hydra attenuata. The bioassays were performed by exposing the organisms to increasing concentrations of the ILs and observing D. magna immobilization, R. subcapitata growth inhibition, and the morphological or mortality effects in H. attenuata. The results demonstrate that the tested organisms are not equally susceptible to the ILs, e.g., bmpyr [BF4] was the least toxic compound for R. subcapitata, N1,1 [N1,1,1OOH] for D. magna and emim [Tf2N] for H. attenuata. This highlights the importance of applying a battery of assays in toxicological analysis. Additionally, Hydra proved to be the most tolerant species to the tested ILs. According to their hazard rankings, the tested ILs are considered practically harmless or moderately toxic, except (Hex)3(TDec)P [Cl], which was classified as highly toxic. The ILs were revealed to be more harmful to aquatic systems than the tested organic solvents, reaffirming the need to analyze carefully the (eco)toxicological impact of these compounds. The present study provides additional data in the evaluation of the potential hazard and the impact of ILs in the environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Claves de las especies del género Agave L. cultivadas como ornamentales en la Península Ibérica e Islas Baleares. Keys to the Agave L. species cultivated as ornamental in Spain

    OpenAIRE

    Guillot Ortiz, Daniel; Van der Meer, Piet

    2006-01-01

    En el siguiente artículo presentamos unas claves dicotómicas para los taxones cultivados como ornamentales del género Agave L. en la Península Ibérica e Islas Baleares, incluyendo numerosos taxones ampliamente cultivados y conocidos como A. americana L., A. sisalana Perrine o A. attenuata Salm.-Dyck, junto a otros muy raros en cultivo en colecciones europeas, como A. avellanidens Trelease, A. nizadensis Cutak, A. neomexicana Wooton & Standley etc., y taxones descritos recientemente en la Pení...

  12. Dicty_cDB: Contig-U15463-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 1 |pid:none) Targionia hypophylla mitochondrial... 270 8e-71 DQ268932_1( DQ268932 |pid:none) Lophocolea hete...|pid:none) Cupriavidus taiwanensis str. LM... 269 1e-70 DQ268931_1( DQ268931 |pid:none) Lepicolea attenuata ...000707 |pid:none) Trichocolea tomentella mitochondri... 270 5e-71 CP001358_1636( CP001358 |pid:none) Desulfo...Q268916 |pid:none) Conocephalum salebrosum NADH dehyd... 270 5e-71 AJ000707_1( AJ

  13. Five new species of Lachenalia (Hyacinthaceae from arid areas of Namibia and South Africa

    Directory of Open Access Journals (Sweden)

    G. Duncan

    1998-12-01

    Full Text Available Five new species of  Lachenalia are described:  L. nutans G.D.Duncan from southwestern Namibia,  L. attenuata W.F.Barker ex G.D Duncan from the Roggeveld Plateau. Little Karoo and southern Cape; L doleritica G.D.Duncan from the Bokkeveld Plateau;  L lactosa G.D.Duncan from the Lowland Fvnbos of the Hermanus District, and  L leipoldtii G D Duncan from the Olifants River Valley and Little Karoo

  14. Jasmonate-dependent depletion of soluble sugars compromises plant resistance to Manduca sexta.

    Science.gov (United States)

    Machado, Ricardo A R; Arce, Carla C M; Ferrieri, Abigail P; Baldwin, Ian T; Erb, Matthias

    2015-07-01

    Jasmonates regulate plant secondary metabolism and herbivore resistance. How they influence primary metabolites and how this may affect herbivore growth and performance are not well understood. We profiled sugars and starch of jasmonate biosynthesis-deficient and jasmonate-insensitive Nicotiana attenuata plants and manipulated leaf carbohydrates through genetic engineering and in vitro complementation to assess how jasmonate-dependent sugar accumulation affects the growth of Manduca sexta caterpillars. We found that jasmonates reduce the constitutive and herbivore-induced concentration of glucose and fructose in the leaves across different developmental stages. Diurnal, jasmonate-dependent inhibition of invertase activity was identified as a likely mechanism for this phenomenon. Contrary to our expectation, both in planta and in vitro approaches showed that the lower sugar concentrations led to increased M. sexta growth. As a consequence, jasmonate-dependent depletion of sugars rendered N. attenuata plants more susceptible to M. sexta attack. In conclusion, jasmonates are important regulators of leaf carbohydrate accumulation and this determines herbivore growth. Jasmonate-dependent resistance is reduced rather than enhanced through the suppression of glucose and fructose concentrations, which may contribute to the evolution of divergent resistance strategies of plants in nature. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  15. Trophic relationships and habitat preferences of delphinids from the southeastern Brazilian coast determined by carbon and nitrogen stable isotope composition.

    Directory of Open Access Journals (Sweden)

    Tatiana Lemos Bisi

    Full Text Available To investigate the foraging habitats of delphinids in southeastern Brazil, we analyzed stable carbon (δ(13C and nitrogen (δ(15N isotopes in muscle samples of the following 10 delphinid species: Sotalia guianensis, Stenella frontalis, Tursiops truncatus, Steno bredanensis, Pseudorca crassidens, Delphinus sp., Lagenodelphis hosei, Stenella attenuata, Stenella longirostris and Grampus griseus. We also compared the δ(13C and δ(15N values among four populations of S. guianensis. Variation in carbon isotope results from coast to ocean indicated that there was a significant decrease in δ(13C values from estuarine dolphins to oceanic species. S. guianensis from Guanabara Bay had the highest mean δ(13C value, while oceanic species showed significantly lower δ(13C values. The highest δ(15N values were observed for P. crassidens and T. truncatus, suggesting that these species occupy the highest trophic position among the delphinids studied here. The oceanic species S. attenuata, G. griseus and L. hosei had the lowest δ(15N values. Stable isotope analysis showed that the three populations of S. guianensis in coastal bays had different δ(13C values, but similar δ(15N results. Guiana dolphins from Sepetiba and Ilha Grande bays had different foraging habitat, with specimens from Ilha Grande showing more negative δ(13C values. This study provides further information on the feeding ecology of delphinids occurring in southeastern Brazil, with evidence of distinctive foraging habitats and the occupation of different ecological niches by these species in the study area.

  16. Pseudoderbesia, nuevo género de algas marinas (Bryopsidaceae, Chlorophyta Pseudoderbesia, nuevo género de algas marinas (Bryopsidaceae, Chlorophyta

    Directory of Open Access Journals (Sweden)

    Calderon Eduardo

    1991-06-01

    Full Text Available Se aislaron cuatro clones de Pseudoderbesia y se mantuvieron como cultivos unialgales: dos provenientes de la Costa Colombiana del Caribe (P. arbuscula y dos de las Islas Canarias en el Océano Atlántico (Pseudoderbesia sp.. Aunque se conoce solo la fase gametofítica, hay razones suficientes para el establecimiento de un nuevo género. Se describe y discute el crecimiento, variabilidad, producción bajo condiciones de cultivo. Se sugiere la posibilidad que ciertas especies de Derbesia que poseen ramificación dicotómica y filamentos gradualmente atenuados, como D. fastigiata, D. attenuata y D. padinae, sean realmente miembros de Pseudoderbesia. Pseudoderbesia is described as a new genus within the Bryopsidaceae. Four clones of Pseudoderbesia were isolated and kept as unialgal cultures: two from the Caribbean coast of Colombia (P. arbuscula and two from the Canary Islands, Atlantic Ocean (Pseudoderbesia sp.. Although only the gametophytic phase is known, it is distinct enough for the establishement of a new genus. Growth, variability and swarmer production, under culture conditions, are described and discussed. It is suggested, that some little known species of Derbesia with dichotomous branching and gradually attenuated filaments, like D. fastigiata, D. attenuata and D. padinae, could actually be members of Pseudoderbesia.

  17. Analysis of Plant-Bacteria Interactions in Their Native Habitat: Bacterial Communities Associated with Wild Tobacco Are Independent of Endogenous Jasmonic Acid Levels and Developmental Stages

    Science.gov (United States)

    Santhanam, Rakesh; Groten, Karin; Meldau, Dorothea G.; Baldwin, Ian T.

    2014-01-01

    Jasmonic acid (JA) mediates defense responses against herbivores and necrotrophic pathogens but does it influence the recruitment of bacterial communities in the field? We conducted field and laboratory experiments with transformed Nicotiana attenuata plants deficient in jasmonate biosynthesis (irAOC) and empty vector controls (EV) to answer this question. Using both culture-dependent and independent techniques, we characterized root and leaf-associated bacterial communities over five developmental stages, from rosette through flowering of plants grown in their natural habitat. Based on the pyrosequencing results, alpha and beta diversity did not differ among EV and irAOC plants or over ontogeny, but some genera were more abundant in one of the genotypes. Furthermore, bacterial communities were significantly different among leaves and roots. Taxa isolated only from one or both plant genotypes and hence classified as ‘specialists’ and ‘generalists’ were used in laboratory tests to further evaluate the patterns observed from the field. The putative specialist taxa did not preferentially colonize the jasmonate-deficient genotype, or alter the plant's elicited phytohormone signaling. We conclude that in N. attenuata, JA signaling does not have a major effect on structuring the bacterial communities and infer that colonization of plant tissues is mainly shaped by the local soil community in which the plant grows. PMID:24728407

  18. Downregulation of net phosphorus-uptake capacity is inversely related to leaf phosphorus-resorption proficiency in four species from a phosphorus-impoverished environment.

    Science.gov (United States)

    de Campos, Mariana C R; Pearse, Stuart J; Oliveira, Rafael S; Lambers, Hans

    2013-03-01

    Previous research has suggested a trade-off between the capacity of plants to downregulate their phosphorus (P) uptake capacity and their efficiency of P resorption from senescent leaves in species from P-impoverished environments. To investigate this further, four Australian native species (Banksia attenuata, B. menziesii, Acacia truncata and A. xanthina) were grown in a greenhouse in nutrient solutions at a range of P concentrations [P]. Acacia plants received between 0 and 500 µm P; Banksia plants received between 0 and 10 µm P, to avoid major P-toxicity symptoms in these highly P-sensitive species. For both Acacia species, the net P-uptake rates measured at 10 µm P decreased steadily with increasing P supply during growth. In contrast, in B. attenuata, the net rate of P uptake from a solution with 10 µm P increased linearly with increasing P supply during growth. The P-uptake rate of B. menziesii showed no significant response to P supply in the growing medium. Leaf [P] of the four species supported this finding, with A. truncata and A. xanthina showing an increase up to a saturation value of 19 and 21 mg P g(-1) leaf dry mass, respectively (at 500 µm P), whereas B. attenuata and B. menziesii both exhibited a linear increase in leaf [P], reaching 10 and 13 mg P g(-1) leaf dry mass, respectively, without approaching a saturation point. The Banksia plants grown at 10 µm P showed mild symptoms of P toxicity, i.e. yellow spots on some leaves and drying and curling of the tips of the leaves. Leaf P-resorption efficiency was 69 % (B. attenuata), 73 % (B. menziesii), 34 % (A. truncata) and 36 % (A. xanthina). The P-resorption proficiency values were 0·08 mg P g(-1) leaf dry mass (B. attenuata and B. menziesii), 0·32 mg P g(-1) leaf dry mass (A. truncata) and 0·36 mg P g(-1) leaf dry mass (A. xanthina). Combining the present results with additional information on P-remobilization efficiency and the capacity to downregulate P-uptake capacity for two other

  19. Tissue concentrations of four Taiwanese toothed cetaceans indicating the silver and cadmium pollution in the western Pacific Ocean.

    Science.gov (United States)

    Chen, Meng-Hsien; Zhuang, Ming-Feng; Chou, Lien-Siang; Liu, Jean-Yi; Shih, Chieh-Chih; Chen, Chiee-Young

    2017-11-30

    Muscle, lung, kidney and liver tissues of 45 bycatch and stranded cetaceans, including 14 Grampus griseus (Gg), 7 Kogia simus (Ks), 10 Lagenodelphis hosei (Lh), and 14 Stenella attenuata (Sa), were collected in the waters off Taiwan from 1994 to 1995, and from 2001 to 2012. Baseline concentrations (in μgg(-1) dry weight) of the cetaceans were lung (liver (0.43±0.28) for Ag, and muscle (0.03±0.03)=lung (0.22±0.19)liver (3.82±3.50)liver-Ag and kidney-Cd were found in two Lh. These Taiwanese cetaceans indicate marked Ag and Cd pollution in the recent two decades in the western Pacific Ocean. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. No junctional communication between epithelial cells in hydra

    DEFF Research Database (Denmark)

    de Laat, S W; Tertoolen, L G; Grimmelikhuijzen, C J

    1980-01-01

    Diffusion gradients of morphogens have been inferred as a basis for the control of morphogenesis in hydra, and morphogenetic substances have been found which, on the basis of their molecular weight (MW), should be able to pass gap junctions. There have been several reports of the presence of gap...... junctions between epithelial cells of hydra. However, until now, there has been no report published on whether these junctions enable the epithelial cells to exchange molecules of small molecular weight, as has been described in other organisms. Therefore we decided to investigate the communicative...... properties of the junctional membranes by electrophysiological methods and by intracellular-dye iontophoresis. We report here that no electrotonic coupling is detectable between epithelial cells of Hydra attenuata in: (1) intact animals, (2) head-regenerating animals, (3) cell re-aggregates, and (4) hydra...

  1. Cetacean diversity on the Parnaiba Delta, Maranhão state, northeastern Brazil

    Directory of Open Access Journals (Sweden)

    FA. Magalhães

    Full Text Available The increase in the research of cetacean surveys on the Brazilian coast has brought new data on the distribution of species never reported before. The present work reviews the current knowledge on cetaceans species and extends this knowledge with an analysis of cetaceans stranded in the Parnaiba Delta, on the coast of Maranhão State, Brazil. The studies on cetacean diversity on the coast of the Parnaíba Delta were made from August 2004 to August 2006. Fourteen strandings were reported, representing six distinct species, such as the estuarine dolphin (Sotalia guianensis, humpback whale (Megaptera novaeangliae, Bryde's whales (Balaenoptera edeni, dwarf minke whale (Balaenoptera acutorostrata, pigmy killer whale (Feresa attenuata, sperm whale (Physeter macrocephalus and two specimens which have not yet been identified. The significant degree of cetacean diversity in the region shows that the Parnaíba Delta is, possibly, of an important area for cetacean studies in Brasil.

  2. Los mamíferos marinos en la costa central de Oaxaca Marine mammals along the central coast of Oaxaca

    Directory of Open Access Journals (Sweden)

    Juan Meraz

    2008-06-01

    Full Text Available Con la finalidad de conocer las especies de mamíferos marinos que se encuentran en la costa central de Oaxaca, se elaboró un listado comentando las características de los registros obtenidos. Se incluyeron las observaciones hechas a lo largo de 30 recorridos por mar, entre junio de 1999 y enero de 2004, realizadas entre las bahías de Huatulco y la playa de La Escobilla. Adicionalmente se incluyeron registros de animales varados, así como observaciones realizadas desde la costa. Se presentan comentarios sobre el registro de 8 especies en la zona, incluyendo las localidades y fechas de los avistamientos. Stenella attenuata es la especie más abundante, y la zona de Zipolite-Isla Roca Blanca la localidad con el mayor número de avistamientos. Dado el crecimiento turístico del lugar, es importante contar con este tipo de registros ya que es poco lo que se sabe sobre estas especies en esta porción de la costa oaxaqueña.With the aim of documenting the species of marine mammals that occur along the central coast of Oaxaca, a list with the characteristics of the records was elaborated based on observations made throughout 30 surveys from Huatulco Bays to La Escobilla beach between June 1999 and January 2004. Additional records from stranded animals are included, as well observations from the coast. Comments on 8 species are presented, including localities and dates of sightings. Stenella attenuata is the most abundant species. Zipolite-Roca Blanca island was the locality with the highest number of sightings. This records are important to promote conservation due growth of tourism in the area, given that Oaxaca coast is poorly known regarding marine mammals.

  3. Natural history-driven, plant-mediated RNAi-based study reveals CYP6B46’s role in a nicotine-mediated antipredator herbivore defense

    Science.gov (United States)

    Kumar, Pavan; Pandit, Sagar S.; Steppuhn, Anke; Baldwin, Ian T.

    2014-01-01

    Manduca sexta (Ms) larvae are known to efficiently excrete ingested nicotine when feeding on their nicotine-producing native hostplant, Nicotiana attenuata. Here we describe how ingested nicotine is co-opted for larval defense by a unique mechanism. Plant-mediated RNAi was used to silence a midgut-expressed, nicotine-induced cytochrome P450 6B46 (CYP6B46) in larvae consuming transgenic N. attenuata plants producing MsCYP6B46 dsRNA. These and transgenic nicotine-deficient plants were planted into native habitats to study the phenotypes of larvae feeding on these plants and the behavior of their predators. The attack-behavior of a native wolf spider (Camptocosa parallela), a major nocturnal predator, provided the key to understanding MsCYP6B46’s function: spiders clearly preferred CYP6B46-silenced larvae, just as they had preferred larvae fed nicotine-deficient plants. MsCYP6B46 redirects a small amount (0.65%) of ingested nicotine from the midgut into hemolymph, from which nicotine is exhaled through the spiracles as an antispider signal. CYP6B46-silenced larvae were more susceptible to spider-attack because they exhaled less nicotine because of lower hemolymph nicotine concentrations. CYP6B46-silenced larvae were impaired in distributing ingested nicotine from midgut to hemolymph, but not in the clearing of hemolymph nicotine or in the exhalation of nicotine from hemolymph. MsCYP6B46 could be a component of a previously hypothesized pump that converts nicotine to a short-lived, transportable, metabolite. Other predators, big-eyed bugs, and antlion larvae were insensitive to this defense. Thus, chemical defenses, too toxic to sequester, can be repurposed for defensive functions through respiration as a form of defensive halitosis, and predators can assist the functional elucidation of herbivore genes. PMID:24379363

  4. Natural history-driven, plant-mediated RNAi-based study reveals CYP6B46's role in a nicotine-mediated antipredator herbivore defense.

    Science.gov (United States)

    Kumar, Pavan; Pandit, Sagar S; Steppuhn, Anke; Baldwin, Ian T

    2014-01-28

    Manduca sexta (Ms) larvae are known to efficiently excrete ingested nicotine when feeding on their nicotine-producing native hostplant, Nicotiana attenuata. Here we describe how ingested nicotine is co-opted for larval defense by a unique mechanism. Plant-mediated RNAi was used to silence a midgut-expressed, nicotine-induced cytochrome P450 6B46 (CYP6B46) in larvae consuming transgenic N. attenuata plants producing MsCYP6B46 dsRNA. These and transgenic nicotine-deficient plants were planted into native habitats to study the phenotypes of larvae feeding on these plants and the behavior of their predators. The attack-behavior of a native wolf spider (Camptocosa parallela), a major nocturnal predator, provided the key to understanding MsCYP6B46's function: spiders clearly preferred CYP6B46-silenced larvae, just as they had preferred larvae fed nicotine-deficient plants. MsCYP6B46 redirects a small amount (0.65%) of ingested nicotine from the midgut into hemolymph, from which nicotine is exhaled through the spiracles as an antispider signal. CYP6B46-silenced larvae were more susceptible to spider-attack because they exhaled less nicotine because of lower hemolymph nicotine concentrations. CYP6B46-silenced larvae were impaired in distributing ingested nicotine from midgut to hemolymph, but not in the clearing of hemolymph nicotine or in the exhalation of nicotine from hemolymph. MsCYP6B46 could be a component of a previously hypothesized pump that converts nicotine to a short-lived, transportable, metabolite. Other predators, big-eyed bugs, and antlion larvae were insensitive to this defense. Thus, chemical defenses, too toxic to sequester, can be repurposed for defensive functions through respiration as a form of defensive halitosis, and predators can assist the functional elucidation of herbivore genes.

  5. New xenophytes from Gran Canaria (Canary Islands, Spain, with emphasis on naturalized and (potentially invasive species

    Directory of Open Access Journals (Sweden)

    Verloove, F.

    2013-12-01

    Full Text Available Trabajos recientes de campo en Gran Canaria han facilitado el descubrimiento de nuevas localidades para plantas vasculares no nativas. Agave attenuata, Antigonon leptopus, Atriplex nummularia, Cascabela thevetia, Cenchrus echinatus, Cuscuta campestris, Diplachne fusca subsp. uninervia, Diplotaxis tenuifolia, Dysphania anthelmintica (hasta ahora confundida con D. ambrosioides, Eclipta prostrata, Euphorbia pulcherrima, Fagopyrum esculentum, Gossypium barbadense, Lablab purpureus, Lemna minuta, Opuntia leucotricha, Passiflora edulis, Pennisetum glaucum, Phaseolus acutifolius, Pluchea carolinensis, Prosopis juliflora, Salvia microphylla, Schinus terebinthifolius, Senna spectabilis, Solanum chrysotrichum, Tecoma stans, Tipuana tipu, Urochloa mutica, U. plantaginea y Washingtonia se citan por primera vez para las Islas Canarias, mientras que Alopecurus myosuroides, Amaranthus blitoides, Bothriochloa ischaemum var. songarica, Cardamine flexuosa subsp. debilis, Heliotropium curassavicum, Leonotis nepetifolia, Medicago lupulina, Parkinsonia aculeata, Physalis peruviana, Phytolacca americana y Turnera ulmifolia son nuevas para la flora de la isla de Gran Canaria. Finalmente, se confirma la presencia de Paspalum vaginatum, P. distichum y Cortaderia selloana en Gran Canaria.Trabajos recientes de campo en Gran Canaria han facilitado el descubrimiento de nuevas localidades para plantas vasculares no nativas. Agave attenuata, Antigonon leptopus, Atriplex nummularia, Cascabela thevetia, Cenchrus echinatus, Cuscuta campestris, Diplachne fusca subsp. uninervia, Diplotaxis tenuifolia, Dysphania anthelmintica (hasta ahora confundida con D. ambrosioides, Eclipta prostrata, Euphorbia pulcherrima, Fagopyrum esculentum, Gossypium barbadense, Lablab purpureus, Lemna minuta, Opuntia leucotricha, Passiflora edulis, Pennisetum glaucum, Phaseolus acutifolius, Pluchea carolinensis, Prosopis juliflora, Salvia microphylla, Schinus terebinthifolius, Senna spectabilis, Solanum

  6. Taxonomic uncertainty and the loss of biodiversity on Christmas Island, Indian Ocean.

    Science.gov (United States)

    Eldridge, Mark D B; Meek, Paul D; Johnson, Rebecca N

    2014-04-01

    The taxonomic uniqueness of island populations is often uncertain which hinders effective prioritization for conservation. The Christmas Island shrew (Crocidura attenuata trichura) is the only member of the highly speciose eutherian family Soricidae recorded from Australia. It is currently classified as a subspecies of the Asian gray or long-tailed shrew (C. attenuata), although it was originally described as a subspecies of the southeast Asian white-toothed shrew (C. fuliginosa). The Christmas Island shrew is currently listed as endangered and has not been recorded in the wild since 1984-1985, when 2 specimens were collected after an 80-year absence. We aimed to obtain DNA sequence data for cytochrome b (cytb) from Christmas Island shrew museum specimens to determine their taxonomic affinities and to confirm the identity of the 1980s specimens. The Cytb sequences from 5, 1898 specimens and a 1985 specimen were identical. In addition, the Christmas Island shrew cytb sequence was divergent at the species level from all available Crocidura cytb sequences. Rather than a population of a widespread species, current evidence suggests the Christmas Island shrew is a critically endangered endemic species, C. trichura, and a high priority for conservation. As the decisions typically required to save declining species can be delayed or deferred if the taxonomic status of the population in question is uncertain, it is hoped that the history of the Christmas Island shrew will encourage the clarification of taxonomy to be seen as an important first step in initiating informed and effective conservation action. © 2013 Society for Conservation Biology.

  7. Assessing the potential toxicity of resuspended sediment

    Energy Technology Data Exchange (ETDEWEB)

    Bonnet, C.; Babut, M.; Ferard, J.F.; Martel, L.; Garric, J.

    2000-05-01

    Two moderately contaminated freshwater sediments (Sorel Harbour, St. Lawrence River, Canada) were subjected to a suspension event. The objective was to assess the environmental impact of the disposal of dredged material in water, in particular, the short-term effects of dumping on the water column and the long-term effects of dredged sediment deposits. In a series of microcosms, the sediments were left to stand for 25 d under flow-through conditions. In a second series of microcosms, sediments were vigorously suspended for 15 min before being left to settle and were submitted to the same treatment as reference sediments during the following 25 d. Physicochemical and biological parameters (Daphnia magna and Hydra attenuata survival) were measured in overlying water throughout the experiment. Sediment toxicity was assessed with Chironomus tentans and Hyalella azteca exposed to sediments collected at both the beginning and end of the 25-d period. Pore-water toxicity was evaluated with D. magna. During the suspension process, in the Sorel Harbour mixed sediment overlying water, the authors observed effects on H. attenuata survival and ammonia and metals (chromium, copper, and zinc) releases. Meanwhile, in reference (nonmixed) and mixed sediments as well as in associated pore waters, there were no significant chemical modifications no biological effects after the 25-d experiments. The developed approach, which attempts to simulate a dumping process, aims at allowing the assessment of the short- and long-term hazards resulting from a resuspension process in overlying water and in resettled sediments using both chemical and biological measurements.

  8. The roots of plant defenses: integrative multivariate analyses uncover dynamic behaviors of gene and metabolic networks of roots elicited by leaf herbivory.

    Science.gov (United States)

    Gulati, Jyotasana; Baldwin, Ian T; Gaquerel, Emmanuel

    2014-03-01

    High-throughput analyses have frequently been used to characterize herbivory-induced reconfigurations in plant primary and secondary metabolism in above- and below-ground tissues, but the conclusions drawn from these analyses are often limited by the univariate methods used to analyze the data. Here we use our previously described multivariate time-series data analysis to evaluate leaf herbivory-elicited transcriptional and metabolic dynamics in the roots of Nicotiana attenuata. We observed large, but transient, systemic responses in the roots that contrasted with the pattern of co-linearity observed in the up- and downregulation of genes and metabolites across the entire time series in treated and systemic leaves. Using this newly developed approach for the analysis of whole-plant molecular responses in a time-course multivariate data set, we simultaneously analyzed stress responses in leaves and roots in response to the elicitation of a leaf. We found that transient systemic responses in roots resolved into two principal trends characterized by: (i) an inversion of root-specific semi-diurnal (12 h) transcript oscillations and (ii) transcriptional changes with major amplitude effects that translated into a distinct suite of root-specific secondary metabolites (e.g. alkaloids synthesized in the roots of N. attenuata). These findings underscore the importance of understanding tissue-specific stress responses in the correct day-night phase context and provide a holistic framework for the important role played by roots in above-ground stress responses. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  9. A rapid and sensitive method for the simultaneous analysis of aliphatic and polar molecules containing free carboxyl groups in plant extracts by LC-MS/MS

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    Bonaventure Gustavo

    2009-11-01

    Full Text Available Abstract Background Aliphatic molecules containing free carboxyl groups are important intermediates in many metabolic and signalling reactions, however, they accumulate to low levels in tissues and are not efficiently ionized by electrospray ionization (ESI compared to more polar substances. Quantification of aliphatic molecules becomes therefore difficult when small amounts of tissue are available for analysis. Traditional methods for analysis of these molecules require purification or enrichment steps, which are onerous when multiple samples need to be analyzed. In contrast to aliphatic molecules, more polar substances containing free carboxyl groups such as some phytohormones are efficiently ionized by ESI and suitable for analysis by LC-MS/MS. Thus, the development of a method with which aliphatic and polar molecules -which their unmodified forms differ dramatically in their efficiencies of ionization by ESI- can be simultaneously detected with similar sensitivities would substantially simplify the analysis of complex biological matrices. Results A simple, rapid, specific and sensitive method for the simultaneous detection and quantification of free aliphatic molecules (e.g., free fatty acids (FFA and small polar molecules (e.g., jasmonic acid (JA, salicylic acid (SA containing free carboxyl groups by direct derivatization of leaf extracts with Picolinyl reagent followed by LC-MS/MS analysis is presented. The presence of the N atom in the esterified pyridine moiety allowed the efficient ionization of 25 compounds tested irrespective of their chemical structure. The method was validated by comparing the results obtained after analysis of Nicotiana attenuata leaf material with previously described analytical methods. Conclusion The method presented was used to detect 16 compounds in leaf extracts of N. attenuata plants. Importantly, the method can be adapted based on the specific analytes of interest with the only consideration that the

  10. A rapid and sensitive method for the simultaneous analysis of aliphatic and polar molecules containing free carboxyl groups in plant extracts by LC-MS/MS.

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    Kallenbach, Mario; Baldwin, Ian T; Bonaventure, Gustavo

    2009-11-25

    Aliphatic molecules containing free carboxyl groups are important intermediates in many metabolic and signalling reactions, however, they accumulate to low levels in tissues and are not efficiently ionized by electrospray ionization (ESI) compared to more polar substances. Quantification of aliphatic molecules becomes therefore difficult when small amounts of tissue are available for analysis. Traditional methods for analysis of these molecules require purification or enrichment steps, which are onerous when multiple samples need to be analyzed. In contrast to aliphatic molecules, more polar substances containing free carboxyl groups such as some phytohormones are efficiently ionized by ESI and suitable for analysis by LC-MS/MS. Thus, the development of a method with which aliphatic and polar molecules -which their unmodified forms differ dramatically in their efficiencies of ionization by ESI- can be simultaneously detected with similar sensitivities would substantially simplify the analysis of complex biological matrices. A simple, rapid, specific and sensitive method for the simultaneous detection and quantification of free aliphatic molecules (e.g., free fatty acids (FFA)) and small polar molecules (e.g., jasmonic acid (JA), salicylic acid (SA)) containing free carboxyl groups by direct derivatization of leaf extracts with Picolinyl reagent followed by LC-MS/MS analysis is presented. The presence of the N atom in the esterified pyridine moiety allowed the efficient ionization of 25 compounds tested irrespective of their chemical structure. The method was validated by comparing the results obtained after analysis of Nicotiana attenuata leaf material with previously described analytical methods. The method presented was used to detect 16 compounds in leaf extracts of N. attenuata plants. Importantly, the method can be adapted based on the specific analytes of interest with the only consideration that the molecules must contain at least one free carboxyl group.

  11. Gastrointestinal parasites of free-living Indo-Pacific bottlenose dolphins (Tursiops aduncus) in the Northern Red Sea, Egypt.

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    Kleinertz, S; Hermosilla, C; Ziltener, A; Kreicker, S; Hirzmann, J; Abdel-Ghaffar, F; Taubert, A

    2014-04-01

    The present study represents the first report on the gastrointestinal parasite fauna infecting the free-living and alive Indo-Pacific bottlenose dolphins (Tursiops aduncus) inhabiting waters of the Red Sea at Hurghada, Egypt. A total of 94 individual faecal samples of the examined bottlenose dolphins were collected during several diving expeditions within their natural habitats. Using classical parasitological techniques, such as sodium acetate acetic acid formalin method, carbol fuchsin-stained faecal smears, coproantigen ELISA, PCR and macroscopical analyses, the study revealed infections with 21 different parasite species belonging to protozoans and metazoans with some of them bearing zoonotic and/or pathogenic potential. Four identified parasite species are potential zoonotic species (Giardia spp., Cryptosporidium spp., Diphyllobothrium spp., Ascaridida indet.); three of them are known to have high pathogenic potential for the examined dolphin species (Nasitrema attenuata, Zalophotrema spp. and Pholeter gastrophilus) and some appear to be directly associated with stranding events. In detail, the study indicates stages of ten protozoan species (Giardia spp., Sarcocystis spp., Isospora (like) spp., Cystoisospora (like) spp., Ciliata indet. I and II, Holotricha indet., Dinoflagellata indet., Hexamita (like) spp., Cryptosporidium spp.), seven trematode species (N. attenuata, Nasitrema spp. I and II, Zalophotrema curilensis, Zalophotrema spp., Pholeter gastrophilus, Trematoda indet.), one cestode species (Diphyllobothrium spp.), two nematode species (Ascaridida indet, Capillaria spp.) and one crustacean parasite (Cymothoidae indet.). Additionally, we molecularly identified adult worms of Anisakis typica in individual dolphin vomitus samples by molecular analyses. A. typica is a common parasite of various dolphin species of warmer temperate and tropical waters and has not been attributed as food-borne parasitic zoonoses so far. Overall, these parasitological findings

  12. Macroalgas submareales de la bahía de Todos Santos, Baja California, México Submareal macroalgae of the Todos Santos Bay, Baja California, Mexico

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    Raúl Aguilar-Rosas

    2010-12-01

    Full Text Available Con el fin de identificar y caracterizar la composición de especies de la zona submareal de la bahía de Todos Santos, Baja California, México; se realizaron muestreos de macroalgas marinas bentónicas en 7 sitios durante 1995-2000. Como resultado de 25 buceos Scuba entre 3 y 33 m de profundidad se encontraron 150 especies de macroalgas para el área de estudio; 10 son Chlorophyta, 26 Phaeophyta y 114 Rhodophyta. Del total, 47 son registros nuevos para el área de estudio y 2 de éstos, Faucheocolax attenuata Setchell y Minium parvum R.L. Moe, son nuevos para la flora marina del Pacífico de México. Se incluye una revisión de las investigaciones en las que se han considerado las macroalgas presentes en la bahía de Todos Santos y una discusión sobre la composición de las especies encontradas, su distribución vertical y reproducción, así como sobre las especies epífitas y parásitas del área.In order to identify and characterize the species composition of the subtidal zone of the Todos Santos Bay, Baja California, Mexico, benthic marine macroalgae were sampled at 7 sites from 1995 to 2000. As a result of 25 scuba at derds for the study area, of which Faucheocolax attenuata Setchell and R.L Moe Minium parvum are new to the marine flora of Pacific Mexico. We include a research that consider the macroalpths between 3 and 33 m we found a total of 150 species of macroalgae for the study area, of which 10 are Chlorophyta, 26 Phaeophyta and 114 Rhodophyta; 47 species represent new recogae in the Todos Santos Bay and a discussion on the composition of species found, its vertical distribution and reproduction, particularly the species epiphytes and parasites present in the study area.

  13. Herbivore perception decreases photosynthetic carbon assimilation and reduces stomatal conductance by engaging 12-oxo-phytodienoic acid, mitogen-activated protein kinase 4 and cytokinin perception.

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    Meza-Canales, Ivan D; Meldau, Stefan; Zavala, Jorge A; Baldwin, Ian T

    2017-07-01

    Herbivory-induced changes in photosynthesis have been documented in many plant species; however, the complexity of photosynthetic regulation and analysis has thwarted progress in understanding the mechanism involved, particularly those elicited by herbivore-specific elicitors. Here, we analysed the early photosynthetic gas exchange responses in Nicotiana attenuata plants after wounding and elicitation with Manduca sexta oral secretions and the pathways regulating these responses. Elicitation with M. sexta oral secretions rapidly decreased photosynthetic carbon assimilation (A C ) in treated and systemic (untreated, vascularly connected) leaves, which were associated with changes in stomatal conductance, rather than with changes in Rubisco activity and 1-5 ribulose-1,5-bisphosphate turnover. Phytohormone profiling and gas exchange analysis of oral secretion-elicited transgenic plants altered in phytohormone regulation, biosynthesis and perception, combined with micrografting techniques, revealed that the local photosynthetic responses were mediated by 12-oxo-phytodienoic acid, while the systemic responses involved interactions among jasmonates, cytokinins and abscisic acid signalling mediated by mitogen-activated protein kinase 4. The analysis also revealed a role for cytokinins interacting with mitogen-activated protein kinase 4 in CO 2 -mediated stomatal regulation. Hence, oral secretions, while eliciting jasmonic acid-mediated defence responses, also elicit 12-oxo-phytodienoic acid-mediated changes in stomatal conductance and A C , an observation illustrating the complexity and economy of the signalling that regulates defence and carbon assimilation pathways in response to herbivore attack. © 2016 John Wiley & Sons Ltd.

  14. A Bayesian integrated population dynamics model to analyze data for protected species

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    Hoyle, S. D.

    2004-06-01

    Full Text Available Managing wildlife-human interactions demands reliable information about the likely consequences of management actions. This requirement is a general one, whatever the taxonomic group. We describe a method for estimating population dynamics and decision analysis that is generally applicable, extremely flexible, uses data efficiently, and gives answers in a useful format. Our case study involves bycatch of a protected species, the Northeastern Offshore Spotted Dolphin (Stenella attenuata, in the tuna fishery of the eastern Pacific Ocean. Informed decision-making requires quantitative analyses taking all relevant information into account, assessing how bycatch affects these species and how regulations affect the fisheries, and describing the uncertainty in analyses. Bayesian analysis is an ideal framework for delivering information on uncertainty to the decision-making process. It also allows information from other populations or species or expert judgment to be included in the analysis, if appropriate. Integrated analysis attempts to include all relevant data for a population into one analysis by combining analyses, sharing parameters, and simultaneously estimating all parameters, using a combined objective function. It ensures that model assumptions and parameter estimates are consistent throughout the analysis, that uncertainty is propagated through the analysis, and that the correlations among parameters are preserved. Perhaps the most important aspect of integrated analysis is the way it both enables and forces consideration of the system as a whole, so that inconsistencies can be observed and resolved.

  15. Uptake and dissipation of neonicotinoid residues in nectar and foliage of systemically treated woody landscape plants.

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    Mach, Bernadette M; Bondarenko, Svetlana; Potter, Daniel A

    2017-10-28

    Systemic neonicotinoid insecticides used in urban arboriculture could pose a risk to bees and other pollinators foraging on treated plants. We measured uptake and dissipation of soil-applied imidacloprid and dinotefuran in nectar and leaves of 2 woody plant species, a broadleaf evergreen tree (Ilex × attenuata) and a deciduous shrub (Clethra alnifolia), to assess concentrations to which pollinators and pests might be exposed in landscape settings. Three application timings, autumn (postbloom), spring (prebloom), and summer (early postbloom), were evaluated to see if taking advantage of differences in the neonicotinoids' systemic mobility and persistence might enable pest control while minimizing transference into nectar. Nectar and tissue samples were collected from in-ground plants and analyzed for residues by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) in 2 successive years. Concentrations found in nectar following autumn or spring applications ranged from 166 to 515 ng/g for imidacloprid and from 70 to 1235 ng/gg for dinotefuran, depending on plant and timing. These residues exceed concentrations shown to adversely affect individual- and colony-level traits of bees. Summer application mitigated concentrations of imidacloprid (8-31 ng/g), but not dinotefuran (235-1191 ng/g), in nectar. Our data suggest that dinotefuran may be more persistent than is generally believed. Implications for integrated pest and pollinator management in urban landscapes are discussed. Environ Toxicol Chem 2017;9999:1-11. © 2017 SETAC. © 2017 SETAC.

  16. Evaluation of sugar-cane vinasse treated with Pleurotus sajor-caju utilizing aquatic organisms as toxicological indicators.

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    Ferreira, Luiz F Romanholo; Aguiar, Mario M; Messias, Tamara G; Pompeu, Georgia B; Lopez, Ana M Queijeiro; Silva, Daniel P; Monteiro, Regina T

    2011-01-01

    Toxicity tests with aquatic organisms constitute an effective tool in the evaluation, prediction and detection of the potential effect of pollutants from environmental samples in living organisms. Vinasse, a highly colored effluent, is a sub-product rich in nutrients, mainly organic matter, with high pollutant potential when disposed in the environment. Assays for vinasse decolorization were performed using the fungus Pleurotus sajor-caju CCB020 in vinasse biodegradation study, were occurred reductions of 82.8% in COD, 75.3% in BOD, 99.2% in the coloration and 99.7% in turbidity. The vinasse toxicity reduction was determined by the exposition to the following organisms: Pseudokirchneriella subcapitata, Daphnia magna, Daphnia similis and Hydra attenuata. This work concluded that the systematic combination of P. sajor-caju and vinasse can be applied in the bioprocess of color reduction and degradation of complex vinasse compounds, with reduction in the toxicity and improving its physical-chemical properties. Copyright © 2010 Elsevier Inc. All rights reserved.

  17. Selection of a bioassay battery to assess toxicity in the affluents and effluents of three water-treatment plants

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    Paola Bohórquez-Echeverry

    2012-08-01

    Full Text Available The assessment of water quality includes the analysis of both physical-chemical and microbiological parameters. However,none of these evaluates the biological effect that can be generated in ecosystems or humans. In order to define the most suitable organismsto evaluate the toxicity in the affluent and effluent of three drinking-water treatment plants, five acute toxicity bioassays were used,incorporating three taxonomic groups of the food chain. Materials and methods. The bioassays used were Daphnia magna and Hydraattenuata as animal models, Lactuca sativa and Pseudokirchneriella subcapitata as plant models, and Photobacterium leioghnathi asbacterial model. To meet this objective, selection criteria of the organisms evaluated and cluster analysis were used to identify the mostsensitive in the affluent and effluent of each plant. Results. All organisms are potentially useful in the assessment of water quality bymeeting four essential requirements and 17 desirable requirements equivalent to 100% acceptability, except P. leioghnathi which doesnot meet two essential requirements that are the IC50 for the toxic reference and the confidence interval. The animal, plant and bacterialmodels showed different levels of sensitivity at the entrance and exit of the water treatment systems. Conclusions. H. attenuata, P.subcapitata and P. leioghnathi were the most effective organisms in detecting toxicity levels in the affluents and D. magna, P. subcapitataand P. leioghnathi in the effluents.

  18. Reverse genetics in ecological research.

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    Jens Schwachtje

    Full Text Available By precisely manipulating the expression of individual genetic elements thought to be important for ecological performance, reverse genetics has the potential to revolutionize plant ecology. However, untested concerns about possible side-effects of the transformation technique, caused by Agrobacterium infection and tissue culture, on plant performance have stymied research by requiring onerous sample sizes. We compare 5 independently transformed Nicotiana attenuata lines harboring empty vector control (EVC T-DNA lacking silencing information with isogenic wild types (WT, and measured a battery of ecologically relevant traits, known to be important in plant-herbivore interactions: phytohormones, secondary metabolites, growth and fitness parameters under stringent competitive conditions, and transcriptional regulation with microarrays. As a positive control, we included a line silenced in trypsin proteinase inhibitor gene (TPI expression, a potent anti-herbivore defense known to exact fitness costs in its expression, in the analysis. The experiment was conducted twice, with 10 and 20 biological replicates per genotype. For all parameters, we detected no difference between any EVC and WT lines, but could readily detect a fitness benefit of silencing TPI production. A statistical power analyses revealed that the minimum sample sizes required for detecting significant fitness differences between EVC and WT was 2-3 orders of magnitude larger than the 10 replicates required to detect a fitness effect of TPI silencing. We conclude that possible side-effects of transformation are far too low to obfuscate the study of ecologically relevant phenotypes.

  19. Phytochemical and Biological Studies of Agave attenuata

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    Vincenzo de Feo

    2012-05-01

    Full Text Available The present study was conducted to examine various biological activities of a methanol extract of Agave attenuata leaves. GC-MS analysis of the n-hexane fraction from the extract revealed the presence of 31 compounds, with mono-2-ethylhexyl phthalate (11.37%, 1,2-benzenedicarboxylic acid (6.33%, n-docosane (6.30% and eicosane (6.02% as the major components. The leaves contained appreciable levels of total phenolic contents (10.541–39.35 GAE, mg/100 g and total flavonoid contents (43.35–304.8 CE, mg/100 g. The extract and some of its fractions showed moderate antimicrobial effects. Leaves extract and fractions also exhibited a good antioxidant potential when measured by DPPH radical scavenging activity and inhibition of lipid peroxidation assays. The hemolytic effect of the plant was found to be in a range of 1.01%–2.64%. From the present study it is concluded that this plant could be used as a source of natural antioxidants and functional food nutraceutical applications.

  20. Nicotine's defensive function in nature.

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    Anke Steppuhn

    2004-08-01

    Full Text Available Plants produce metabolites that directly decrease herbivore performance, and as a consequence, herbivores are selected for resistance to these metabolites. To determine whether these metabolites actually function as defenses requires measuring the performance of plants that are altered only in the production of a certain metabolite. To date, the defensive value of most plant resistance traits has not been demonstrated in nature. We transformed native tobacco(Nicotiana attenuata with a consensus fragment of its two putrescine N-methyl transferase (pmt genes in either antisense or inverted-repeat (IRpmt orientations. Only the latter reduced (by greater than 95% constitutive and inducible nicotine. With D(4-nicotinic acid (NA, we demonstrate that silencing pmt inhibits nicotine production, while the excess NA dimerizes to form anatabine. Larvae of the nicotine-adapted herbivore Manduca sexta (tobacco hornworm grew faster and, like the beetle Diabrotica undecimpunctata, preferred IRpmt plants in choice tests. When planted in their native habitat, IRpmt plants were attacked more frequently and, compared to wild-type plants, lost 3-fold more leaf area from a variety of native herbivores, of which the beet armyworm, Spodoptera exigua, and Trimerotropis spp. grasshoppers caused the most damage. These results provide strong evidence that nicotine functions as an efficient defense in nature and highlights the value of transgenic techniques for ecological research.

  1. Identification of novel Bartonella spp. in bats and evidence of Asian gray shrew as a new potential reservoir of Bartonella.

    Science.gov (United States)

    Lin, Jen-Wei; Hsu, Yuan-Man; Chomel, Bruno B; Lin, Liang-Kong; Pei, Jai-Chyi; Wu, Sheng-Hai; Chang, Chao-Chin

    2012-04-23

    Many studies indicated that small mammals are important reservoirs for Bartonella species. Using molecular methods, several studies have documented that bats could harbor Bartonella. This study was conducted to investigate the relationship of Bartonella spp. identified in bats and small mammals living in the same ecological environment. During May 2009 and March 2010, a total of 102 blood specimens were collected. By whole blood culture and molecular identification, a total of 6 bats, 1 rodent and 9 shrews were shown to be infected by Bartonella species. After sequencing and phylogenetic analyses of the sequences of gltA, ftsZ, rpoB and ribC genes, these specific isolates from bats were not similar to the known Bartonella species (the similarity values were less than 91.2%, 90.5%, 88.8%, and 82.2%, respectively); these isolates formed an independent clade away from other known Bartonella type strains. The Bartonella spp. isolated from small mammals, which were closely related to Bartonella tribocorum, Bartonella elizabethae, Bartonella grahamii, Bartonella rattimassiliensis and Bartonella queenslandensis, were similar to the findings in previous studies worldwide. Therefore, the results implied that the species of Bartonella strains isolated from small mammals were different from those identified in bats. Our results strongly suggested that the bat isolate could be a new Bartonella species. This study is also the first one to isolate Bartonella organisms from Asian gray shrews, Crocidura attenuata tanakae. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Chemical and ecotoxicological assessments of water samples before and after being processed by a Water Treatment Plant

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    Regina Teresa Rosim Monteiro

    2014-01-01

    Full Text Available Physicochemical and ecotoxicological measurements were employed to appraise the water quality of the Corumbataí River raw water (RW intake, and that of its filtered (FW and treated (TW waters, processed by the Water Treatment Plant (WTP of Piracicaba (SP, Brazil during 2010. Some herbicides: ametrine, atrazine, simazine and tebuthiuron, were measured, with levels ranging from 0.01 to 10.3 µg L-1 . These were lower than those required to produce ecotoxicological effects to aquatic life based on published literature. Similarly, trihalomethanes, such as chloroform and bromodichloromethane produced as a result of the WTP process were also shown to be present in concentrations that would neither harm environmental nor human health. Elevated free chlorine concentrations found in FW and TW were credibly responsible for toxicity effects observed in algae and daphnids. (Pseudokirchneriella subcapitata and Daphnia magna. In contrast, results of toxicity testing conducted with Hydra attenuata suggested that this organism is resistant to free chorine and could be used for drinking water evaluations. Coupling bioassays with chemical analyses proved valuable to uncover putative cause-effect relationships existing between physical, chemical and toxic results, as well as in optimizing data interpretation of water quality.

  3. Degradation of textile dyes by cyanobacteria

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    Priscila Maria Dellamatrice

    Full Text Available Abstract Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black, and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds.

  4. Plant defense phenotypes determine the consequences of volatile emission for individuals and neighbors

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    Schuman, Meredith C; Allmann, Silke; Baldwin, Ian T

    2015-01-01

    Plants are at the trophic base of terrestrial ecosystems, and the diversity of plant species in an ecosystem is a principle determinant of community structure. This may arise from diverse functional traits among species. In fact, genetic diversity within species can have similarly large effects. However, studies of intraspecific genetic diversity have used genotypes varying in several complex traits, obscuring the specific phenotypic variation responsible for community-level effects. Using lines of the wild tobacco Nicotiana attenuata genetically altered in specific well-characterized defense traits and planted into experimental populations in their native habitat, we investigated community-level effects of trait diversity in populations of otherwise isogenic plants. We conclude that the frequency of defense traits in a population can determine the outcomes of these traits for individuals. Furthermore, our results suggest that some ecosystem-level services afforded by genetically diverse plant populations could be recaptured in intensive monocultures engineered to be functionally diverse. DOI: http://dx.doi.org/10.7554/eLife.04490.001 PMID:25873033

  5. Refractory sampling links efficiency and costs of sensory encoding to stimulus statistics.

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    Song, Zhuoyi; Juusola, Mikko

    2014-05-21

    Sensory neurons integrate information about the world, adapting their sampling to its changes. However, little is understood mechanistically how this primary encoding process, which ultimately limits perception, depends upon stimulus statistics. Here, we analyze this open question systematically by using intracellular recordings from fly (Drosophila melanogaster and Coenosia attenuata) photoreceptors and corresponding stochastic simulations from biophysically realistic photoreceptor models. Recordings show that photoreceptors can sample more information from naturalistic light intensity time series (NS) than from Gaussian white-noise (GWN), shuffled-NS or Gaussian-1/f stimuli; integrating larger responses with higher signal-to-noise ratio and encoding efficiency to large bursty contrast changes. Simulations reveal how a photoreceptor's information capture depends critically upon the stochastic refractoriness of its 30,000 sampling units (microvilli). In daylight, refractoriness sacrifices sensitivity to enhance intensity changes in neural image representations, with more and faster microvilli improving encoding. But for GWN and other stimuli, which lack longer dark contrasts of real-world intensity changes that reduce microvilli refractoriness, these performance gains are submaximal and energetically costly. These results provide mechanistic reasons why information sampling is more efficient for natural/naturalistic stimulation and novel insight into the operation, design, and evolution of signaling and code in sensory neurons. Copyright © 2014 Song and Juusola.

  6. Degradation of textile dyes by cyanobacteria.

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    Dellamatrice, Priscila Maria; Silva-Stenico, Maria Estela; Moraes, Luiz Alberto Beraldo de; Fiore, Marli Fátima; Monteiro, Regina Teresa Rosim

    Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black), and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  7. SYNTAXONOMY OF TUNDRA, CRYOPHYTIC STEPPE, NIVAL AND ALPINE MEADOWS IN THE HIGHLANDS OF THE SOUTHEAST ALTAI

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    M. Yu. Telyatnikov

    2015-04-01

    Full Text Available The material in this article supplements the results of the studies carried out by us earlier in the high mountains of the south-eastern Altai. Ten associations and 13 subassociations were described that are assigned to six classes of eco-floristic classification. Six associations and 13 subassociations are described the first time. Tundra vegetation is confined to northern slopes of ridges, while steppes occupy southern slopes of the mountains. Alpine altitudinal zone is dominated by Kobresia and Dryas tundra (associations Rhytidio rugosi-Oxytropidetum alpinae. In the subalpine zone dwarf birch thicket (ass. Hylocomio splendentis-Caricetum sabynensis and dwarf birch tundra (ass. Aulacomnio turgidi-Lagotidetum integrifoliae are common. This zone is also characterized by nival meadows (ass. Anthoxantho alpini-Schulzietum crinitae. Cryo-steppe belt is dominated by graminoid steppes (ass. Carici rupestris-Festucetum krylovianae in its upper part, while in the lower part forb graminoid cryophytic steppes (ass. Poo attenuatae-Festucetum tschujensis prevail. For the cryo-steppe belt species-rich alpine meadows (ass. Thalictro alpini-Trollietum asiatici, ass. Antennario dioicae-Pulsatilletum patentis are also typical.

  8. Cetáceos de las aguas costeras del Pacífico norte y sur de Costa Rica

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    Damián Martínez-Fernández

    2011-03-01

    Full Text Available De las 29 especies de cetáceos presentes en Costa Rica, se han realizado investigaciones exhaustivas solamente para tres especies. Lo anterior evidencia la poca información general existente sobre cetáceos, a pesar de que Costa Rica posee un notable crecimiento de actividades de avistamiento. Debido al uso que se está generando en las zonas costeras, cada vez se hace más necesario determinar la ocurrencia de cetáceos en zonas de alta actividad turística, con el fin de proponer medidas de conservación. En el presente estudio, se determinaron variables ambientales que estaban relacionadas con la presencia de especies registradas, a partir de 166 avistamientos entre el 2005 y 2006. Las especies con mayor proporción de avistamientos fueron Stenella attenuata (68%, seguida por Megaptera novaeangliae (13% y Tursiops truncatus (10%. La presencia del delfín manchado se relaciona con cambios de salinidad y trasparencia del agua, mientras que la de la ballena jorobada estuvo relacionada con el oleaje y la temperatura superficial del agua. Se confirma la presencia de 7 especies de cetáceos en dos zonas costeras del Pacífico de Costa Rica, de las cuales tres están presentes a lo largo del año. Se encontraron variables ambientales relacionadas con la presencia de al menos dos especies.

  9. Activated carbon from pyrolysed sugarcane bagasse: Silver nanoparticle modification and ecotoxicity assessment.

    Science.gov (United States)

    Gonçalves, Suely Patrícia C; Strauss, Mathias; Delite, Fabrício S; Clemente, Zaira; Castro, Vera L; Martinez, Diego Stéfani T

    2016-09-15

    Activated carbon from pyrolysed sugarcane bagasse (ACPB) presented pore size ranges from 1.0 to 3.5nm, and surface area between 1200 and 1400m(2)g(-1) that is higher than commonly observed to commercial activated carbon. The ACPB material was successfully loaded with of silver nanoparticles with diameter around 35nm (0.81wt.%). X-ray photoelectron spectroscopy (XPS) analyses showed that the material surface contains metallic/Ag(0) (93.60wt.%) and ionic/Ag(+) states (6.40wt.%). The adsorption capacity of organic model molecules (i.e. methylene blue and phenol) was very efficient to ACPB and ACPB loaded with silver nanoparticles (ACPB-AgNP), indicating that the material modification with silver nanoparticles has not altered its adsorption capacity. ACPB-AgNP inhibited bacteria growth (Escherichia coli), it is a promising advantage for the use of these materials in wastewater treatment and water purification processes. However, ACPB-AgNP showed environmental risks, with toxic effect to the aquatic organism Hydra attenuata (i.e. LC50 value of 1.94mgL(-1)), and it suppressed root development of Lycopersicum esculentum plant (tomato). Finally, this work draw attention for the environmental implications of activated carbon materials modified with silver nanoparticles. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Intraspecific combinations of flower and leaf volatiles act together in attracting hawkmoth pollinators.

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    Zsolt Kárpáti

    Full Text Available Insects pinpoint mates, food and oviposition sites by olfactory cues. Recognizing and localizing a suitable target by olfaction is demanding. Odor sources emit characteristic blends of compounds that have to be identified against an environmentally derived olfactory background. This background, however, does not necessarily disturb the localization of a source. Rather, the contrary. Sex pheromones become more attractive to male moths when being presented against a relevant plant background. Here we asked whether such olfactory coaction also characterizes foraging cues. The tobacco hornworm Manduca sexta feeds on nectar from wild tobacco Nicotiana attenuata and sacred datura Datura wrightii flowers. We tested how leaf-derived volatile blends as a background affect the moths' approach to flower blends. We found coaction when a flower blend was presented against a conspecific leaf volatile background but not when the blend was presented against volatiles emitted by the other host plant or by a non-host plant. Hence, our results reveal a species-specific coaction between flower blend and leaf volatile background. The ability to integrate information from different odor sources on one plant might provide the moth with a fine-grained analysis of food site quality.

  11. Full establishment of arbuscular mycorrhizal symbiosis in rice occurs independently of enzymatic jasmonate biosynthesis.

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    Caroline Gutjahr

    Full Text Available Development of the mutualistic arbuscular mycorrhiza (AM symbiosis between most land plants and fungi of the Glomeromycota is regulated by phytohormones. The role of jasmonate (JA in AM colonization has been investigated in the dicotyledons Medicago truncatula, tomato and Nicotiana attenuata and contradicting results have been obtained with respect to a neutral, promotive or inhibitory effect of JA on AM colonization. Furthermore, it is currently unknown whether JA plays a role in AM colonization of monocotyledonous roots. Therefore we examined whether JA biosynthesis is required for AM colonization of the monocot rice. To this end we employed the rice mutant constitutive photomorphogenesis 2 (cpm2, which is deficient in JA biosynthesis. Through a time course experiment the amount and morphology of fungal colonization did not differ between wild-type and cpm2 roots. Furthermore, no significant difference in the expression of AM marker genes was detected between wild type and cpm2. However, treatment of wild-type roots with 50 μM JA lead to a decrease of AM colonization and this was correlated with induction of the defense gene PR4. These results indicate that JA is not required for AM colonization of rice but high levels of JA in the roots suppress AM development likely through the induction of defense.

  12. Full establishment of arbuscular mycorrhizal symbiosis in rice occurs independently of enzymatic jasmonate biosynthesis.

    Science.gov (United States)

    Gutjahr, Caroline; Siegler, Heike; Haga, Ken; Iino, Moritoshi; Paszkowski, Uta

    2015-01-01

    Development of the mutualistic arbuscular mycorrhiza (AM) symbiosis between most land plants and fungi of the Glomeromycota is regulated by phytohormones. The role of jasmonate (JA) in AM colonization has been investigated in the dicotyledons Medicago truncatula, tomato and Nicotiana attenuata and contradicting results have been obtained with respect to a neutral, promotive or inhibitory effect of JA on AM colonization. Furthermore, it is currently unknown whether JA plays a role in AM colonization of monocotyledonous roots. Therefore we examined whether JA biosynthesis is required for AM colonization of the monocot rice. To this end we employed the rice mutant constitutive photomorphogenesis 2 (cpm2), which is deficient in JA biosynthesis. Through a time course experiment the amount and morphology of fungal colonization did not differ between wild-type and cpm2 roots. Furthermore, no significant difference in the expression of AM marker genes was detected between wild type and cpm2. However, treatment of wild-type roots with 50 μM JA lead to a decrease of AM colonization and this was correlated with induction of the defense gene PR4. These results indicate that JA is not required for AM colonization of rice but high levels of JA in the roots suppress AM development likely through the induction of defense.

  13. Stand structure of a primate rich rainforest region in the central Western Ghats of southern India

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    K. Roy

    2010-06-01

    Full Text Available The Western Ghats of southern India are one of the most important biodiversity regions in the world, not only due to their faunal diversity and abundance but also due to different habitat types, floral diversity and the presence of several endemic plant species. The rainforests in the central Western Ghats are inhabited by several primate species. We investigated the vegetation pattern and tree species occupancy of one of the prime primate habitats in the central Western Ghats. Lion-tailed Macaque (Macaca silenus, Bonnet Macaque (Macaca radiata, Hanuman Langur (Semnopithecus entellus achates and Malabar Slender Loris (Loris lydekkerianus malabaricus inhabit the study area. We studied the density, dominance, frequency and Importance Value Index (IVI of different tree species, using the belt transect method on randomly selected plots covering 4.1ha. We found that all the plant species that emerged to be the most dominant species with high IVI in the forest were also used by the diurnal primates for foraging. Knema attenuata and Syzygium gardneri were found to be the ‘keystone’ species. Since the forests of the study area do not come under the ‘protected area network’ for wildlife, the data obtained during this study will be helpful in the forestry management practices with a view for wildlife conservation of the region.

  14. Herbivory-induced jasmonates constrain plant sugar accumulation and growth by antagonizing gibberellin signaling and not by promoting secondary metabolite production.

    Science.gov (United States)

    Machado, Ricardo A R; Baldwin, Ian T; Erb, Matthias

    2017-07-01

    Plants respond to herbivory by reconfiguring hormonal networks, increasing secondary metabolite production and decreasing growth. Furthermore, some plants display a decrease in leaf energy reserves in the form of soluble sugars and starch, leading to the hypothesis that herbivory-induced secondary metabolite production and growth reduction may be linked through a carbohydrate-based resource trade-off. In order to test the above hypothesis, we measured leaf carbohydrates and plant growth in seven genetically engineered Nicotiana attenuata genotypes that are deficient in one or several major herbivore-induced, jasmonate-dependent defensive secondary metabolites and proteins. Furthermore, we manipulated gibberellin and jasmonate signaling, and quantified the impact of these phytohormones on secondary metabolite production, sugar accumulation and growth. Simulated herbivore attack by Manduca sexta specifically reduced leaf sugar concentrations and growth in a jasmonate-dependent manner. These effects were similar or even stronger in defenseless genotypes with intact jasmonate signaling. Gibberellin complementation rescued carbohydrate accumulation and growth in induced plants without impairing the induction of defensive secondary metabolites. These results are consistent with a hormonal antagonism model rather than a resource-cost model to explain the negative relationship between herbivory-induced defenses, leaf energy reserves and growth. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  15. Cetacean records along São Paulo state coast, Southeastern Brazil

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    Marcos César de Oliveira Santos

    2010-06-01

    Full Text Available The São Paulo state (SP coast (23º18'S, 44º42'W; 25º14'S, 48º01'W is of approximately 600 km in length, bordering the Western Atlantic Ocean, in southeastern Brazil. Cetacean sightings and strandings have long been observed throughout this area. Scattered data from scientific publications, skeletal remains in museums, photographs and articles from newspaper files, universities and aquaria have been organised and updated since 1993. Field investigations on strandings and sightings have also been conducted. A total of 29 cetacean species have been recorded, including 7 baleen whales (Mysticeti and 22 toothed whales (Odontoceti, as follows: Balaenoptera physalus, B. borealis, B. edeni, B. acutorostrata, B. bonaerensis, Megaptera novaeangliae, Eubalaena australis, Physeter macrocephalus, Kogia breviceps, K. sima, Berardius arnuxii, Mesoplodon europaeus, M. mirus, Ziphius cavirostris, Orcinus orca, Feresa attenuata, Globicephala melas, G. macrorhynchus, Pseudorca crassidens, Delphinus capensis, Lagenodelphis hosei, Steno bredanensis, Tursiops truncatus, Stenella frontalis, S. longirostris, S. coeruleoalba, Lissodelphis peronii, Sotalia guianensis and Pontoporia blainvillei. Several species have been observed only once and include strays from their areas of common distribution, as well as species with known preferences for offshore distribution. Others, such as P. blainvillei and S. guianensis, are common coastal dwellers year-round. Z. cavirostris, P. crassidens and L. hosei are reported for the first time on the SP coast.A costa do Estado de São Paulo (SP (23º18'S, 44º42'O; 25º14'S, 48º01'O apresenta aproximadamente 600 km de extensão voltada para o Oceano Atlântico Ocidental no sudeste do Brasil. Registros de encalhes e de avistamentos de cetáceos vêm sendo realizados ao longo desse litoral. Desde 1993, dados obtidos em literatura científica, material osteológico encontrado em museus, fotografias e artigos de arquivos de jornais

  16. Actividad molusquicida del Piquerol A aislado de Piqueria trinervia (compositae sobre ocho especies de caracoles pulmonados The molluscicide activity of Piquerol A isolated from Piqueria trinervia (Compositae against eight species of pulmonate snails

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    Alejandro Cruz-Reys

    1989-03-01

    Full Text Available De las partes aéreas de la planta Piqueria trinervia (Compositae colectada en diveresas áereas de México, se aisló el Piquerol A. Este compuesto se probó como agente molusquicida contra ocho especies de caracoles pulmonados: Fossaria (Fossaria humilis, F. (Bakerilymnae sp., Pseudosuccinea columella, Stagnicola attenuata, de México; F. (B. cubensis y Physacubensis, de Cuba; P. Columella y Biomphalaria glabrata, de Brasil; B glabrata, de Puerto Rico; S. elodes, de Estados Unidos. Se utilizaron tres concentraciones 50, 25 y 5 ppm para cada una de las especies y 2 períodos de exposición, 6 y 24 horas, a 20-22ºC. En 50 ppm, después de 6 horas, y 25 ppm, después de 24 horas los ejemplares de todas las especies murieron. En 5 ppm después de 24 horas, se observaron mortalidades de 60 a 100%. En ningún caso se observó recuperación después de la exposición por 24 horas. El piquerol A es un terpeno biodegradable que presenta otras actividades biológicas. No se han hecho pruebas de toxicidad en otros animales ni pruebas de campo. Sin embargo, es una substacia con alto potencial de uso como molusquicida en zonas de transmisión focal. Es la primera que en México se hacen estudios sistemáticos sobre molusquicidas de origen vegetal.In laboratory trials an aqueous solution of Piquerol A from Piqueria trinervia, collected in several regions of Mexico, showed a molluscicide action on the adults of eight different pulmonates snails species. Fossaria (Fossaria humilis, F. (Bakerilymnaea sp., Pseudosuccinea columella and Stagnicola attenuata from Mexico; F. (B. cubensis and Physa cubensis from Cuba; P. columella and Biomphalaria glabrata from Brazil; B. glabrata from Puerto Rico; and S. elodes from USA. The solution was tested at 50, 25 and 5 ppm concentration, for two periods of 6 and 24 hours, at room temperature (20-22ºC. A 100% mortality was obtained for all species at 50 ppm concentration after 6 hours of exposure; the same percentage at 25

  17. Patterns of cetacean sighting distribution in the Pacific Exclusive Economic Zone of Costa Rica based on data collected from 1979-2001

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    Laura May-Collado

    2005-06-01

    Full Text Available Nineteen species of cetaceans (families Balaenopteridae, Kogiidae, Physeteridae, Ziphiidae and Delphinidae occur in the Costa Rican Pacific Exclusive Economic Zone (EEZ. Based on data recorded from the EEZ by the Southwest Fisheries Service Center, Cascadia Research Collective, and CIMAR between 1979- 2001, we mapped the distribution of 18 cetacean species. Our results suggest that the majority of the cetacean species use primarily oceanic waters, particularly those species within the families Balaenopteridae, Kogiidae, Physeteridae and Ziphiidae. Members of the family Delphinidae showed a wide variety of distribution patterns: seven species are widespread throughout the EEZ, four appear to be exclusively pelagic, and two are primarily coastal. Overall, three cetacean species appear to have populations concentrated in coastal waters: Stenella attenuata graffmani, Tursiops truncatus, and Megaptera novaeangliae. These three may be more susceptible to human activities due to the overlap of their ranges with fishery areas (tuna and artisanal fisheries, and an uncontrolled increase of touristic whale watching activities in several parts of their range. The distribution maps represent the first comprehensive representation of cetacean species that inhabit Costa Rican Pacific waters. They provide essential base-line information that may be used to initiate conservation and management efforts of the habitats where these animals reproduce and forage. Rev. Biol. Trop. 53(1-2:249-263.Epub 2005 Jun 24Diecinueve especies de cetáceos distribuídos en cinco familias (Balaenopteridae, Kogiidae, Physeteridae, Ziphiidae and Delphinidae habitan en la Zona Económica Exclusiva del Pacífico de Costa Rica (ZEEP. Con base a datos tomados en esta zona por el Southwest Fisheries Service Center, Cascadia Research Collective y CIMAR entre 1979 y 2001 construímos mapas de distribución de avistamientos para 18 especies. Nuestros resultados sugieren que la mayoría de

  18. Cetáceos de las aguas costeras del Pacífico norte y sur de Costa Rica

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    Damián Martínez-Fernández

    2011-03-01

    Full Text Available De las 29 especies de cetáceos presentes en Costa Rica, se han realizado investigaciones exhaustivas solamente para tres especies. Lo anterior evidencia la poca información general existente sobre cetáceos, a pesar de que Costa Rica posee un notable crecimiento de actividades de avistamiento. Debido al uso que se está generando en las zonas costeras, cada vez se hace más necesario determinar la ocurrencia de cetáceos en zonas de alta actividad turística, con el fin de proponer medidas de conservación. En el presente estudio, se determinaron variables ambientales que estaban relacionadas con la presencia de especies registradas, a partir de 166 avistamientos entre el 2005 y 2006. Las especies con mayor proporción de avistamientos fueron Stenella attenuata (68%, seguida por Megaptera novaeangliae (13% y Tursiops truncatus (10%. La presencia del delfín manchado se relaciona con cambios de salinidad y trasparencia del agua, mientras que la de la ballena jorobada estuvo relacionada con el oleaje y la temperatura superficial del agua. Se confirma la presencia de 7 especies de cetáceos en dos zonas costeras del Pacífico de Costa Rica, de las cuales tres están presentes a lo largo del año. Se encontraron variables ambientales relacionadas con la presencia de al menos dos especies.Inshore cetaceans from the North and South Pacific coast of Costa Rica. Twenty nine cetacean species occur in Costa Rican waters but extensive research has been conducted only for three species. The latter shows there is a lack of general and local information about these mammals, even when the country, has shown a remarkable growth in whale watching activities. The increasing use of marine resources in coastal areas has also developed the need to determine the occurrence of cetaceans in areas showing high tourist presence, in order to propose sound conservation measures. In this study, environmental variables were determined and subsequently related to the

  19. A Rapid and Reliable Method for Total Protein Extraction from Succulent Plants for Proteomic Analysis.

    Science.gov (United States)

    Lledías, Fernando; Hernández, Felipe; Rivas, Viridiana; García-Mendoza, Abisaí; Cassab, Gladys I; Nieto-Sotelo, Jorge

    2017-08-01

    Crassulacean acid metabolism plants have some morphological features, such as succulent and reduced leaves, thick cuticles, and sunken stomata that help them prevent excessive water loss and irradiation. As molecular constituents of these morphological adaptations to xeric environments, succulent plants produce a set of specific compounds such as complex polysaccharides, pigments, waxes, and terpenoids, to name a few, in addition to uncharacterized proteases. Since all these compounds interfere with the analysis of proteins by electrophoretic techniques, preparation of high quality samples from these sources represents a real challenge. The absence of adequate protocols for protein extraction has restrained the study of this class of plants at the molecular level. Here, we present a rapid and reliable protocol that could be accomplished in 1 h and applied to a broad range of plants with reproducible results. We were able to obtain well-resolved SDS/PAGE protein patterns in extracts from different members of the subfamilies Agavoideae (Agave, Yucca, Manfreda, and Furcraea), Nolinoideae (Dasylirion and Beucarnea), and the Cactaceae family. This method is based on the differential solubility of contaminants and proteins in the presence of acetone and pH-altered solutions. We speculate about the role of saponins and high molecular weight carbohydrates to produce electrophoretic-compatible samples. A modification of the basic protocol allowed the analysis of samples by bidimensional electrophoresis (2DE) for proteomic analysis. Furostanol glycoside 26-O-β-glucosidase (an enzyme involved in steroid saponin synthesis) was successfully identified by mass spectrometry analysis and de novo sequencing of a 2DE spot from an Agave attenuata sample.

  20. Diversity and Distribution Patterns of Cetaceans in the Subtropical Southwestern Atlantic Outer Continental Shelf and Slope.

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    Juliana Couto Di Tullio

    Full Text Available Temporal and spatial patterns of cetacean diversity and distribution were investigated through eight ship-based surveys carried out during spring and autumn between 2009 and 2014 on the outer continental shelf (~150m and slope (1500m off southeastern and southern Brazil (~23°S to ~34°S. The survey area was divided into southeast and south areas according to their oceanographic characteristics. Twenty-one species were observed in 503 sightings. The overall number of species was similar between the two areas, though it was higher in the spring in the south area. Five species were dominant and diversity varied more seasonally than spatially. ANOVA and kernel analyses showed that overall cetacean densities were higher in spring compared to autumn. Physeter macrocephalus, the most frequent species, concentrated throughout the south area at depths over 1000m in both seasons. Despite the overlapped occurrence at a broader scale, small delphinids presented latitudinal and in-offshore gradients as well as seasonal variation in distribution patterns, which could indicate habitat partitioning between some species. Delphinus delphis was only recorded in the south and its density decreased in areas where the presence of Stenella frontalis increased, mainly beyond the 250m isobath. Densities of S. longirostris and S. attenuata increased in lower latitudes and beyond the shelf break. The large delphinids Tursiops truncatus and Globicephala melas formed mixed groups in many occasions and were observed along the study area around depths of 500m. Grampus griseus was twice as frequent in the south area and densities increased in waters deeper than 600m. As expected, densities of both small and large migratory whales were higher during spring, over the continental slope, in the southeast area. The results presented here provided strong evidence on the importance of the outer continental shelf and slope to a diverse community of cetaceans occurring in the

  1. Diversity and Distribution Patterns of Cetaceans in the Subtropical Southwestern Atlantic Outer Continental Shelf and Slope.

    Science.gov (United States)

    Di Tullio, Juliana Couto; Gandra, Tiago B R; Zerbini, Alexandre N; Secchi, Eduardo R

    2016-01-01

    Temporal and spatial patterns of cetacean diversity and distribution were investigated through eight ship-based surveys carried out during spring and autumn between 2009 and 2014 on the outer continental shelf (~150m) and slope (1500m) off southeastern and southern Brazil (~23°S to ~34°S). The survey area was divided into southeast and south areas according to their oceanographic characteristics. Twenty-one species were observed in 503 sightings. The overall number of species was similar between the two areas, though it was higher in the spring in the south area. Five species were dominant and diversity varied more seasonally than spatially. ANOVA and kernel analyses showed that overall cetacean densities were higher in spring compared to autumn. Physeter macrocephalus, the most frequent species, concentrated throughout the south area at depths over 1000m in both seasons. Despite the overlapped occurrence at a broader scale, small delphinids presented latitudinal and in-offshore gradients as well as seasonal variation in distribution patterns, which could indicate habitat partitioning between some species. Delphinus delphis was only recorded in the south and its density decreased in areas where the presence of Stenella frontalis increased, mainly beyond the 250m isobath. Densities of S. longirostris and S. attenuata increased in lower latitudes and beyond the shelf break. The large delphinids Tursiops truncatus and Globicephala melas formed mixed groups in many occasions and were observed along the study area around depths of 500m. Grampus griseus was twice as frequent in the south area and densities increased in waters deeper than 600m. As expected, densities of both small and large migratory whales were higher during spring, over the continental slope, in the southeast area. The results presented here provided strong evidence on the importance of the outer continental shelf and slope to a diverse community of cetaceans occurring in the subtropical Southwestern

  2. Activated carbon from pyrolysed sugarcane bagasse: Silver nanoparticle modification and ecotoxicity assessment

    Energy Technology Data Exchange (ETDEWEB)

    Gonçalves, Suely Patrícia C., E-mail: suely.goncalves@lnnano.cnpem.br [Brazilian Nanotechnology National Laboratory (LNNano), Brazilian Center for Research in Energy and Materials (CNPEM), CEP 13083-970 Campinas, SP (Brazil); Strauss, Mathias; Delite, Fabrício S. [Brazilian Nanotechnology National Laboratory (LNNano), Brazilian Center for Research in Energy and Materials (CNPEM), CEP 13083-970 Campinas, SP (Brazil); Clemente, Zaira [Brazilian Nanotechnology National Laboratory (LNNano), Brazilian Center for Research in Energy and Materials (CNPEM), CEP 13083-970 Campinas, SP (Brazil); Laboratory of Ecotoxicology and Biosafety, Embrapa, CEP 13820-000 Jaguariúna, SP (Brazil); Castro, Vera L. [Laboratory of Ecotoxicology and Biosafety, Embrapa, CEP 13820-000 Jaguariúna, SP (Brazil); Martinez, Diego Stéfani T., E-mail: diego.martinez@lnnano.cnpem.br [Brazilian Nanotechnology National Laboratory (LNNano), Brazilian Center for Research in Energy and Materials (CNPEM), CEP 13083-970 Campinas, SP (Brazil); School of Technology, University of Campinas (UNICAMP), CEP 13484-332 Limeira, SP (Brazil)

    2016-09-15

    Activated carbon from pyrolysed sugarcane bagasse (ACPB) presented pore size ranges from 1.0 to 3.5 nm, and surface area between 1200 and 1400 m{sup 2} g{sup −1} that is higher than commonly observed to commercial activated carbon. The ACPB material was successfully loaded with of silver nanoparticles with diameter around 35 nm (0.81 wt.%). X-ray photoelectron spectroscopy (XPS) analyses showed that the material surface contains metallic/Ag{sup 0} (93.60 wt.%) and ionic/Ag{sup +} states (6.40 wt.%). The adsorption capacity of organic model molecules (i.e. methylene blue and phenol) was very efficient to ACPB and ACPB loaded with silver nanoparticles (ACPB-AgNP), indicating that the material modification with silver nanoparticles has not altered its adsorption capacity. ACPB-AgNP inhibited bacteria growth (Escherichia coli), it is a promising advantage for the use of these materials in wastewater treatment and water purification processes. However, ACPB-AgNP showed environmental risks, with toxic effect to the aquatic organism Hydra attenuata (i.e. LC50 value of 1.94 mg L{sup −1}), and it suppressed root development of Lycopersicum esculentum plant (tomato). Finally, this work draw attention for the environmental implications of activated carbon materials modified with silver nanoparticles. - Highlights: • Production of very efficient activated carbon by pyrolysis process of sugarcane bagasse. • Modification of activated carbon with silver nanoparticles to environmental remediation and water purification. • Activated carbon modified with silver nanoparticles showed acute ecotoxic effects.

  3. Using the knowns to discover the unknowns: MS-based dereplication uncovers structural diversity in 17-hydroxygeranyllinalool diterpene glycoside production in the Solanaceae.

    Science.gov (United States)

    Heiling, Sven; Khanal, Santosh; Barsch, Aiko; Zurek, Gabriela; Baldwin, Ian T; Gaquerel, Emmanuel

    2016-02-01

    Exploring the diversity of plant secondary metabolism requires efficient methods to obtain sufficient structural insights to discriminate previously known from unknown metabolites. De novo structure elucidation and confirmation of known metabolites (dereplication) remain a major bottleneck for mass spectrometry-based metabolomic workflows, and few systematic dereplication strategies have been developed for the analysis of entire compound classes across plant families, partly due to the complexity of plant metabolic profiles that complicates cross-species comparisons. 17-hydroxygeranyllinalool diterpene glycosides (HGL-DTGs) are abundant defensive secondary metabolites whose malonyl and glycosyl decorations are induced by jasmonate signaling in the ecological model plant Nicotiana attenuata. The multiple labile glycosidic bonds of HGL-DTGs result in extensive in-source fragmentation (IS-CID) during ionization. To reconstruct these IS-CID clusters from profiling data and identify precursor ions, we applied a deconvolution algorithm and created an MS/MS library from positive-ion spectra of purified HGL-DTGs. From this library, 251 non-redundant fragments were annotated, and a workflow to characterize leaf, flower and fruit extracts of 35 solanaceous species was established. These analyses predicted 105 novel HGL-DTGs that were restricted to Nicotiana, Capsicum and Lycium species. Interestingly, malonylation is a highly conserved step in HGL-DTG metabolism, but is differentially affected by jasmonate signaling among Nicotiana species. This MS-based workflow is readily applicable for cross-species re-identification/annotation of other compound classes with sufficient fragmentation knowledge, and therefore has the potential to support hypotheses regarding secondary metabolism diversification. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  4. Circadian rhythms in floral scent emission

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    Myles eFenske

    2016-04-01

    Full Text Available To successfully recruit pollinators, plants often release attractive floral scents at specific times of day to coincide with pollinator foraging. This timing of scent emission is thought to be evolutionarily beneficial to maximize resource efficiency while attracting only useful pollinators. Temporal regulation of scent emission is tied to the activity of the specific metabolic pathways responsible for scent production. Although floral volatile profiling in various plants indicated a contribution by the circadian clock, the mechanisms by which the circadian clock regulates timing of floral scent emission remained elusive. Recent studies using two species in the Solanaceae family provided initial insight into molecular clock regulation of scent emission timing. In Petunia hybrida, the benzenoid/phenylpropanoid (FVBP pathway is the major metabolic pathway that produces floral volatiles. Three MYB-type transcription factors, ODORANT1 (ODO1, EMISSION OF BENZENOIDS I (EOBI, and EOBII, all of which show diurnal rhythms in mRNA expression, act as positive regulators for several enzyme genes in the FVBP pathway. Recently, in P. hybrida and Nicotiana attenuata, homologs of the Arabidopsis clock gene LATE ELONGATED HYPOCOTYL (LHY have been shown to have a similar role in the circadian clock in these plants, and to also determine the timing of scent emission. In addition, in P. hybrida, PhLHY directly represses ODO1 and several enzyme genes in the FVBP pathway during the morning as an important negative regulator of scent emission. These findings facilitate our understanding of the relationship between a molecular timekeeper and the timing of scent emission, which may influence reproductive success.

  5. Microscale ecotoxicity testing of Moselle river watershed (Lorraine Province, France sediments

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    Jean François Férard

    2015-06-01

    Full Text Available The ecotoxic potential of seven Moselle river watershed sediments was assessed with a battery of bioassays comprised of rapid phototrophic [LuminoTox solid phase (L-SPA and elutriate (L-ELU assays] and bacterial [Microtox solid phase assay (M-SPA] exposure tests, as well as with two micro-invertebrate solid phase tests conducted with Hydra attenuata (lethal and sublethal effects solid phase assay, HL-SPA and HSL-SPA and Chironomus riparius. Measured effects of sediments and their elutriates were varied and reflected responses that were ecotoxicity test-, endpoint- and site-dependent, suggesting some degree of risk toward benthic and water column organisms, respectively, at specific sites. Correlation analysis demonstrated that L-SPA and M-SPA ecotoxicity responses were significantly linked with the Hydra HSL-SPA assay, indicating their ability to predict ecotoxicity towards an invertebrate taxonomic group representing secondary consumers. While the L-SPA and M-SPA assays hold promise as rapid screens for sediment ecotoxicity, correlation analysis with grain size (L-SPA: r=-0.795, P=0.033; M-SPA: r=-0.73, P=0.07 points out that their responses can be influenced by the presence of fines (i.e., sediment particles ≤0.063 mm in size and that this information is essential to properly interpret ecotoxicity data generated with these assays. Finally, notable differences observed in trophic level sensitivities once again recall the importance of employing a test battery to adequately appraise the ecotoxicity of sediments.

  6. Illuminating a plant's tissue-specific metabolic diversity using computational metabolomics and information theory.

    Science.gov (United States)

    Li, Dapeng; Heiling, Sven; Baldwin, Ian T; Gaquerel, Emmanuel

    2016-11-22

    Secondary metabolite diversity is considered an important fitness determinant for plants' biotic and abiotic interactions in nature. This diversity can be examined in two dimensions. The first one considers metabolite diversity across plant species. A second way of looking at this diversity is by considering the tissue-specific localization of pathways underlying secondary metabolism within a plant. Although these cross-tissue metabolite variations are increasingly regarded as important readouts of tissue-level gene function and regulatory processes, they have rarely been comprehensively explored by nontargeted metabolomics. As such, important questions have remained superficially addressed. For instance, which tissues exhibit prevalent signatures of metabolic specialization? Reciprocally, which metabolites contribute most to this tissue specialization in contrast to those metabolites exhibiting housekeeping characteristics? Here, we explore tissue-level metabolic specialization in Nicotiana attenuata, an ecological model with rich secondary metabolism, by combining tissue-wide nontargeted mass spectral data acquisition, information theory analysis, and tandem MS (MS/MS) molecular networks. This analysis was conducted for two different methanolic extracts of 14 tissues and deconvoluted 895 nonredundant MS/MS spectra. Using information theory analysis, anthers were found to harbor the most specialized metabolome, and most unique metabolites of anthers and other tissues were annotated through MS/MS molecular networks. Tissue-metabolite association maps were used to predict tissue-specific gene functions. Predictions for the function of two UDP-glycosyltransferases in flavonoid metabolism were confirmed by virus-induced gene silencing. The present workflow allows biologists to amortize the vast amount of data produced by modern MS instrumentation in their quest to understand gene function.

  7. Wild tobacco genomes reveal the evolution of nicotine biosynthesis.

    Science.gov (United States)

    Xu, Shuqing; Brockmöller, Thomas; Navarro-Quezada, Aura; Kuhl, Heiner; Gase, Klaus; Ling, Zhihao; Zhou, Wenwu; Kreitzer, Christoph; Stanke, Mario; Tang, Haibao; Lyons, Eric; Pandey, Priyanka; Pandey, Shree P; Timmermann, Bernd; Gaquerel, Emmanuel; Baldwin, Ian T

    2017-06-06

    Nicotine, the signature alkaloid of Nicotiana species responsible for the addictive properties of human tobacco smoking, functions as a defensive neurotoxin against attacking herbivores. However, the evolution of the genetic features that contributed to the assembly of the nicotine biosynthetic pathway remains unknown. We sequenced and assembled genomes of two wild tobaccos, Nicotiana attenuata (2.5 Gb) and Nicotiana obtusifolia (1.5 Gb), two ecological models for investigating adaptive traits in nature. We show that after the Solanaceae whole-genome triplication event, a repertoire of rapidly expanding transposable elements (TEs) bloated these Nicotiana genomes, promoted expression divergences among duplicated genes, and contributed to the evolution of herbivory-induced signaling and defenses, including nicotine biosynthesis. The biosynthetic machinery that allows for nicotine synthesis in the roots evolved from the stepwise duplications of two ancient primary metabolic pathways: the polyamine and nicotinamide adenine dinucleotide (NAD) pathways. In contrast to the duplication of the polyamine pathway that is shared among several solanaceous genera producing polyamine-derived tropane alkaloids, we found that lineage-specific duplications within the NAD pathway and the evolution of root-specific expression of the duplicated Solanaceae-specific ethylene response factor that activates the expression of all nicotine biosynthetic genes resulted in the innovative and efficient production of nicotine in the genus Nicotiana Transcription factor binding motifs derived from TEs may have contributed to the coexpression of nicotine biosynthetic pathway genes and coordinated the metabolic flux. Together, these results provide evidence that TEs and gene duplications facilitated the emergence of a key metabolic innovation relevant to plant fitness.

  8. Navigating natural variation in herbivory-induced secondary metabolism in coyote tobacco populations using MS/MS structural analysis.

    Science.gov (United States)

    Li, Dapeng; Baldwin, Ian T; Gaquerel, Emmanuel

    2015-07-28

    Natural variation can be extremely useful in unraveling the determinants of phenotypic trait evolution but has rarely been analyzed with unbiased metabolic profiling to understand how its effects are organized at the level of biochemical pathways. Native populations of Nicotiana attenuata, a wild tobacco species, have been shown to be highly genetically diverse for traits important for their interactions with insects. To resolve the chemodiversity existing in these populations, we developed a metabolomics and computational pipeline to annotate leaf metabolic responses to Manduca sexta herbivory. We selected seeds from 43 accessions of different populations from the southwestern United States--including the well-characterized Utah 30th generation inbred accession--and grew 183 plants in the glasshouse for standardized herbivory elicitation. Metabolic profiles were generated from elicited leaves of each plant using a high-throughput ultra HPLC (UHPLC)-quadrupole TOFMS (qTOFMS) method, processed to systematically infer covariation patterns among biochemically related metabolites, as well as unknown ones, and finally assembled to map natural variation. Navigating this map revealed metabolic branch-specific variations that surprisingly only partly overlapped with jasmonate accumulation polymorphisms and deviated from canonical jasmonate signaling. Fragmentation analysis via indiscriminant tandem mass spectrometry (idMS/MS) was conducted with 10 accessions that spanned a large proportion of the variance found in the complete accession dataset, and compound spectra were computationally assembled into spectral similarity networks. The biological information captured by this networking approach facilitates the mining of the mass spectral data of unknowns with high natural variation, as demonstrated by the annotation of a strongly herbivory-inducible phenolic derivative, and can guide pathway analysis.

  9. Navigating natural variation in herbivory-induced secondary metabolism in coyote tobacco populations using MS/MS structural analysis

    Science.gov (United States)

    Li, Dapeng; Baldwin, Ian T.; Gaquerel, Emmanuel

    2015-01-01

    Natural variation can be extremely useful in unraveling the determinants of phenotypic trait evolution but has rarely been analyzed with unbiased metabolic profiling to understand how its effects are organized at the level of biochemical pathways. Native populations of Nicotiana attenuata, a wild tobacco species, have been shown to be highly genetically diverse for traits important for their interactions with insects. To resolve the chemodiversity existing in these populations, we developed a metabolomics and computational pipeline to annotate leaf metabolic responses to Manduca sexta herbivory. We selected seeds from 43 accessions of different populations from the southwestern United States—including the well-characterized Utah 30th generation inbred accession—and grew 183 plants in the glasshouse for standardized herbivory elicitation. Metabolic profiles were generated from elicited leaves of each plant using a high-throughput ultra HPLC (UHPLC)-quadrupole TOFMS (qTOFMS) method, processed to systematically infer covariation patterns among biochemically related metabolites, as well as unknown ones, and finally assembled to map natural variation. Navigating this map revealed metabolic branch-specific variations that surprisingly only partly overlapped with jasmonate accumulation polymorphisms and deviated from canonical jasmonate signaling. Fragmentation analysis via indiscriminant tandem mass spectrometry (idMS/MS) was conducted with 10 accessions that spanned a large proportion of the variance found in the complete accession dataset, and compound spectra were computationally assembled into spectral similarity networks. The biological information captured by this networking approach facilitates the mining of the mass spectral data of unknowns with high natural variation, as demonstrated by the annotation of a strongly herbivory-inducible phenolic derivative, and can guide pathway analysis. PMID:26170304

  10. Príspevok k topografickému výskumu malakofauny okresu Levice

    Directory of Open Access Journals (Sweden)

    Jozef Šteffek

    2005-11-01

    Full Text Available The paper brings new information on mollusc distribution of Levice District in southern part of Central Slovakia. The data were obtained from 14 localities, which lie mainly in the vicinity of the Ipeľ River and southern slopes of Štiavnické vrchy Mts. Together 78 mollusc species (50 land species and 28 fresh-water species were found. From 9 localities a litter sample from 1m2 was analyzed for quantitative evaluation of snail assemblages. Malacocoenoses of thermophilous forest mollusc species were determined in the area of Štiavnické vrchy Mts. foothill (localities 2, 7, 8. The species Limacus flavus, Euconulus praticola, Pisidium amnicum and Unio crassus albensis are important from the viewpoint of nature conservation and geographical distribution. Carpathian species Bythinella austriaca, Vestia turgida, Bielzia coerulans and also European forest species Merdigera obscura reach the southern boundary of their natural area of occurrence. Typical for this region are malacocoenoses of xeric biotopes, composed from species of 4–6 ecoelement – Cecilioides acicula, Cepaea vindobonensis, Granaria frumentum, Chondrula tridens, Xerolenta obvia, Truncatellina cylindrica, Cochlicopa lubricella and Monacha cartusiana. High diversity was observed by freshwater malacocoenoses. Anodonta anatina attenuata, A. cygnea solearis, Unio tumidus zelebori, Radix ampla are typical for stagnant water biotopes (abandoned ‘paleopotamon’ side arms. In slow flowing waters of the Ipeľ River beside the common species also rare species like Anisus septemgyratus and Pisidium amnicum were detected. Interesting is also the occurrence of strong population of invasive species of Asian mussel Sinanodonta woodiana, which is known to infiltrate into a number of streams all around Slovakia.

  11. Histological, immunohistochemical and pathological features of the pituitary gland of odontocete cetaceans from the Western gulf of Mexico.

    Science.gov (United States)

    Cowan, D F; Haubold, E M; Tajima, Y

    2008-01-01

    Pituitary glands were recovered from dolphins and small whales found stranded along the Texas coast of the Gulf of Mexico over a 15-year period (1991-2006). One hundred animals of 14 species were found to be suitable for inclusion in this study. Of these, 72 were Atlantic bottlenose dolphins (Tursiops truncatus). Other species included were the melon-headed whale (Peponocephala electra), spinner dolphin (Stenella longirostris), striped dolphin (Stenella coeruleoalba), pantropical spotted dolphin (Stenella attenuata), pygmy sperm whale (Kogia breviceps), dwarf sperm whale (Kogia sima), Risso's dolphin (Grampus griseus), the short finned pilot whale (Globicephala macrorhyncha), false killer whale (Pseudorca crassidens), Fraser's dolphin (Lagenorhynchus hosei), rough-tooth dolphin (Steno bredanensis), Gervais's beaked whale (Mesoplodon europaeus) and an infant sperm whale (Physeter catodon). The pituitary weights in T. truncatus ranged from 0.69 g in a 109-cm long neonate to 3.44 g in a large (277 cm) male. More typical weights were in the range of 0.95-2.35 g (mean=1.65+/-0.70 g) The cetacean pituitary consisted of two distinct parts, the adenohypophysis and the neurohypophysis, which were separated by a thin fibrous membrane in all species examined, in contrast to terrestrial mammals in which the parts are apposed and joined through a pars intermedia. Cell types were identified with conventional stains and immunohistochemistry. Cells positive for adrenocorticotropic hormone, follicle stimulating hormone, growth hormone, melanocyte stimulating hormone, luteinizing hormone and prolactin were identified with appropriate antibodies. Lesions, which were few, included one pituicytoma of the pars nervosa and a squamous cyst in T. truncatus, and colloid cysts in several species. Nodular aggregates of single cell types were common, probably representing a physiological variant.

  12. Efecto de sedimentos naturales enriquecidos con zinc, en modelos aislados y en microcosmos, sobre tres especies de invertebrados bentónicos

    Directory of Open Access Journals (Sweden)

    Marcela Galar Martínez

    2006-06-01

    Full Text Available En los cuerpos acuáticos la disponibilidad de los tóxicos es limitada por las características fisicoquímicas de los sedimentos y agua, así como por las interacciones entre los diversos xenobióticos y entre las especies que los habitan. Por lo anterior, el objetivo del presente trabajo fue relacionar el efecto producido por el zinc (Zn sembrado en sedimentos del embalse Ignacio Ramírez (PIR, en modelos aislados y en microcosmos, sobre el ATP de tres organismos bentónicos con la biodisponibilidad del metal. Las especies seleccionadas fueron: Hyalella azteca, Limnodrilus hoffmeisteri y Stagnicola attenuata, dado que se encuentran en altas proporciones en el embalse y ocupan espacios diferentes en el bentos. Las muestras de sedimentos y organismos se colectaron en la estación de sequía (febrero de 1999. A los primeros se les determinó el pH, textura, tamaño de partícula, nitrógeno total, materia orgánica y concentración de metales (Zn, Fe, Cu y Ni. Posteriormente se realizó un estudio de toxicidad subletal utilizando dos tipos de sistemas estáticos (organismos aislados y en microcosmos. Ambos modelos contenían sedimentos de la PIR enriquecidos con Zn (concentración nominal de 0.8129 mg/kg y agua sintética en una proporción de 1:4. Los organismos de prueba fueron adicionados una vez alcanzado el equilibrio (2 hr considerando la cantidad de biomasa con respecto al volumen (1.0 g de organismo por cada 100 ml de agua:sedimento. Después de 0, 12, 24, 36, 48 y 72 hr de exposición se tomaron muestras del sedimento y de los hidrobiontes, a los cuales se les cuantificó el contenido de Zn por absorción atómica. A los organismos también se les determinó la concentración de ATP. Los resultados obtenidos muestran que el efecto producido por los sedimentos naturales enriquecidos se ve potenciado por la presencia de más de una especie en el sistema (microcosmos. Con respecto a los niveles de Zn, dos de los organismos (L. hoffmeisteri

  13. Feeding ecology of the Stomiiformes (Pisces) of the northern Mid-Atlantic Ridge. 1. The Sternoptychidae and Phosichthyidae

    Science.gov (United States)

    Carmo, Vanda; Sutton, Tracey; Menezes, Gui; Falkenhaug, Tone; Bergstad, Odd Aksel

    2015-01-01

    Comprehensive trophic studies in the vast mid-oceanic regions are rare compared to coastal and fisheries-oriented investigations. Field sampling conducted by the multidisciplinary, international Census of Marine Life project MAR-ECO, namely the 2004 G.O. Sars cruise, has generated one of the largest open ocean deep-pelagic sample collections ever obtained. With the overall goal of understanding carbon flow processes within and through the deep-pelagic nekton associated with the northern Mid-Atlantic Ridge system (N MAR), quantitative trophic analyses were conducted in order to identify the major intraspecific patterns in diet of characteristic members of the midwater fish community. Diets of five abundant species of zooplanktivorous fishes were examined in detail in terms of prey taxonomy and variability in space, ontogeny and diel cycle. Two major patterns of feeding were identified. Pattern 1 included three species preying primarily on copepods, Argyropelecus hemigymnus, Maurolicus muelleri and Vinciguerria attenuata, the former two of which revealed spatial differences in diet with latitude, mostly likely related to latitudinal prey distributions and densities. Maurolicus demonstrated ecological differences in diet that mirrored phenotypic variation North and South of the Subpolar Front, an 'oceanic species concept' question that warrants further research. Pattern 2 included two species feeding primarily on amphipods, Argyropelecus aculeatus and Sternoptyx diaphana, both of which showed ontogenetic variability in feeding primarily related to specific amphipod taxon sizes, rather than prey switching to other major prey taxa. This is the first study that highlights the importance of amphipods in the diets of these species. All fish species showed selectivity in prey choice, possibly related to competition with the other major nekton components along the N MAR, namely the Myctophidae and other zooplanktivorous Stomiiformes. Daily ration fell within the expected

  14. Response of marine copepods to a changing tropical environment: winners, losers and implications

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    Li Lee Chew

    2016-05-01

    Full Text Available Background. Climate change concurrent with anthropogenic disturbances can initiate serial changes that reverberate up the food chain with repercussions for fisheries. To date, there is no information available concerning the combined effects of global warming and human impacts on tropical marine food webs. While temperate copepods respond differently to warming and environmental stressors, the extent to which tropical copepods can adapt to rising temperature of already warm waters remains unknown. We hypothesize that sea warming and other anthropogenic disturbances over the long term will have the greatest impact on the copepod community in nearshore waters where their effects are accentuated, and therefore vulnerable and resilient species could be identified. Methods. Zooplankton samples were collected during two time periods (1985–86 and 2014–15 interposed by marked anthropogenic disturbances, and at the same five stations located progressively from inshore to offshore in Klang Strait, Malaysia, following the asymmetrical before-after-control-impact (BACI design. Copepods were identified to species, and results were interpreted by univariate (ANOVA and multivariate (PERMANOVA, PCO analyses of the computed species abundance and diversity measures. Results. Copepod total abundance was not significantly different among stations but higher after disturbance than before disturbance. However, changes in the abundance of particular species and the community structure between time periods were dramatic. Coastal large-bodied calanoid species (e.g., Acartia spinicauda, Calanopia thompsoni, Pseudodiaptomus bowmani and Tortanus forcipatus were the most vulnerable group to disturbance. This however favored the opportunistic species (e.g., Oithona simplex, O. attenuata, Hemicyclops sp., Pseudomacrochiron sp. and Microsetella norvegica. Small-bodied copepods (e.g., Paracalanus sp., Parvocalanus crassirostris and Euterpina acutifrons were unaffected

  15. Response of marine copepods to a changing tropical environment: winners, losers and implications.

    Science.gov (United States)

    Chew, Li Lee; Chong, Ving Ching

    2016-01-01

    Background. Climate change concurrent with anthropogenic disturbances can initiate serial changes that reverberate up the food chain with repercussions for fisheries. To date, there is no information available concerning the combined effects of global warming and human impacts on tropical marine food webs. While temperate copepods respond differently to warming and environmental stressors, the extent to which tropical copepods can adapt to rising temperature of already warm waters remains unknown. We hypothesize that sea warming and other anthropogenic disturbances over the long term will have the greatest impact on the copepod community in nearshore waters where their effects are accentuated, and therefore vulnerable and resilient species could be identified. Methods. Zooplankton samples were collected during two time periods (1985-86 and 2014-15) interposed by marked anthropogenic disturbances, and at the same five stations located progressively from inshore to offshore in Klang Strait, Malaysia, following the asymmetrical before-after-control-impact (BACI) design. Copepods were identified to species, and results were interpreted by univariate (ANOVA) and multivariate (PERMANOVA, PCO) analyses of the computed species abundance and diversity measures. Results. Copepod total abundance was not significantly different among stations but higher after disturbance than before disturbance. However, changes in the abundance of particular species and the community structure between time periods were dramatic. Coastal large-bodied calanoid species (e.g., Acartia spinicauda, Calanopia thompsoni, Pseudodiaptomus bowmani and Tortanus forcipatus) were the most vulnerable group to disturbance. This however favored the opportunistic species (e.g., Oithona simplex, O. attenuata, Hemicyclops sp., Pseudomacrochiron sp. and Microsetella norvegica). Small-bodied copepods (e.g., Paracalanus sp., Parvocalanus crassirostris and Euterpina acutifrons) were unaffected. Centropages

  16. Coating carbon nanotubes with humic acid using an eco-friendly mechanochemical method: Application for Cu(II) ions removal from water and aquatic ecotoxicity.

    Science.gov (United States)

    Côa, Francine; Strauss, Mathias; Clemente, Zaira; Rodrigues Neto, Laís L; Lopes, Josias R; Alencar, Rafael S; Souza Filho, Antônio G; Alves, Oswaldo L; Castro, Vera Lúcia S S; Barbieri, Edison; Martinez, Diego Stéfani T

    2017-12-31

    In this work, industrial grade multi-walled carbon nanotubes (MWCNT) were coated with humic acid (HA) for the first time by means of a milling process, which can be considered an eco-friendly mechanochemical method to prepare materials and composites. The HA-MWCNT hybrid material was characterized by atomic force microscopy (AFM), scanning electron microscopies (SEM and STEM), X-ray photoelectron spectroscopy (XPS), termogravimetric analysis (TGA), and Raman spectroscopy. STEM and AFM images demonstrated that the MWCNTs were efficiently coated by the humic acid, thus leading to an increase of 20% in the oxygen content at the nanotube surface as observed by the XPS data. After the milling process, the carbon nanotubes were shortened as unveiled by SEM images and the values of ID/IG intensity ratio increased due to shortening of the nanotubes and increasing in the number defects at the graphitic structure of carbon nanotubes walls. The analysis of TGA data showed that the quantity of the organic matter of HA on the nanotube surface was 25%. The HA coating was responsible to favor the dispersion of MWCNTs in ultrapure water (i.e. -42mV, zeta-potential value) and to improve their capacity for copper removal. HA-MWCNTs hybrid material adsorbed 2.5 times more Cu(II) ions than oxidized MWCNTs with HNO3, thus evidencing that it is a very efficient adsorbent material for removing copper ions from reconstituted water. The HA-MWCNTs hybrid material did not show acute ecotoxicity to the tested aquatic model organisms (Hydra attenuata, Daphnia magna, and Danio rerio embryos) up to the highest concentration evaluated (10mgL-1). The results allowed concluding that the mechanochemical method is effective to coat carbon nanotubes with humic acid, thus generating a functional hybrid material with low aquatic toxicity and great potential to be applied in environmental nanotechnologies such as the removal of heavy metal ions from water. Copyright © 2017 Elsevier B.V. All rights

  17. Studies on the community structures of meiofauna and marine nematode at six stations in the Southern Yellow Sea, China

    Science.gov (United States)

    Huang, Yong; Zhang, Zhinan; Liu, Xiaoshou

    2005-01-01

    Meiofauna (0.031-0.5 mm) were sampled and studied at a grid of six stations during the cruise of investigation for over winter ground of anchovy ( Engraulis japonicus) in the Southern Yellow Sea, China in January 2003. Total meiofauna individuals averaged (1.162±0.347) × 106 ind m-2 and the corresponding biomass 1.748 ± 0.72 g dwt m-2 with the maximum 2.35g dwt m-2 at Station 9594 and the minimum 0.537g dwt m-2 at Station 11794. A total of fourteen taxa were identified. Free living marine nematodes were the most dominant group with an average abundance of (1.026 ± 0.206) × 106 ind m-2, accounting for 88.5% of total numbers, and an average of 85.4% lived in the surface layer (0-2 cm) of sediments. The individual dry weight was calculated, which ranges from O.Ol µg to 31.32f*g with an average of 0.261 µg. One hundred and forty two species or taxa of free-living marine nematodes belonging to 89 genera, 24 families and 4 orders were identified. Six of them were new species. The common dominant species were Dorylaimopsis rabalaisi, Sphaerolaimus balticus, Sphaerolaimus minitus, Metalinhomoeus longicauda, Prochromadorella attenuata., Campylaimus sp. 1, Vasostoma sp. 1, Daptonema normandicum, Paramonohystera riemanni, and Promonhystera sp.1. According to cluster analysis of Primer 5.0, the six stations were clustered into 2 groups with similar species composition at 40% similarity. The species diversity index (J), evenness index (d) and species richness index (d) of nematode were calculated and analyzed. Correlation analysis with respect to environmental factors showed that the abundance of meiofauna had a significant correlation with the median diameter of sediment (Mdø). The species richness of nematodes had a highly significant correlation with Chl-a and significant correlations with Pha-a and Chl-a + Pha-a.

  18. High-throughput quantification of more than 100 primary- and secondary-metabolites, and phytohormones by a single solid-phase extraction based sample preparation with analysis by UHPLC-HESI-MS/MS.

    Science.gov (United States)

    Schäfer, Martin; Brütting, Christoph; Baldwin, Ian T; Kallenbach, Mario

    2016-01-01

    Plant metabolites are commonly functionally classified, as defense- or growth-related phytohormones, primary and specialized metabolites, and so forth. Analytical procedures for the quantifications of these metabolites are challenging because the metabolites can vary over several orders of magnitude in concentrations in the same tissues and have very different chemical characteristics. Plants clearly adjust their metabolism to respond to their prevailing circumstances in very sophisticated ways that blur the boundaries among these functional or chemically defined classifications. But if plant biologists want to better understand the processes that are important for a plant's adaptation to its environment, procedures are needed that can provide simultaneous quantifications of the large range of metabolites that have the potential to play central roles in these adjustments in a cost and time effective way and with a low sample consumption. Here we present a method that combines well-established methods for the targeted analysis of phytohormones, including jasmonates, salicylic acid, abscisic acid, gibberellins, auxins and cytokinins, and extends it to the analysis of inducible and constitutive defense compounds, as well as the primary metabolites involved in the biosynthesis of specialized metabolites and responsible for nutritional quality (e.g., sugars and amino acids). The method is based on a single extraction of 10-100 mg of tissue and allows a broad quantitative screening of metabolites optimized by their chemical characteristics and concentrations, thereby providing a high throughput analysis unbiased by the putative functional attributes of the metabolites. The tissues of Nicotiana attenuata which accumulate high levels of nicotine and diterpene glycosides, provide a challenging matrix that thwarts quantitative analysis; the analysis of various tissues of this plant are used to illustrate the robustness of the procedure. The method described has the

  19. Revision of the funnel-web spider genus Novalena (Araneae: Agelenidae).

    Science.gov (United States)

    Maya-Morales, Julieta; Jiménez, María Luisa

    2017-05-05

    The Western Hemisphere genus Novalena Chamberlin & Ivie 1942 (Araneae: Agelenidae) is revised. The genus now includes a total of 53 species, of which 40 are new species from USA, Mexico, Guatemala, and Costa Rica: N. ajusco sp. nov. (♀), N. alamo sp. nov. (♂), N. alvarezi sp. nov. (♀), N. atzimbo sp. nov. (♀), N. bosencheve sp. nov. (♂), N. chamberlini sp. nov. (♂ ♀), N. cieneguilla sp. nov. (♀), N. cintalapa sp. nov. (♂ ♀), N. clara sp. nov. (♂ ♀), N. comaltepec sp. nov. (♀), N. creel sp. nov. (♂ ♀), N. dentata sp. nov. (♂ ♀), N. divisadero sp. nov. (♀), N. durango sp. nov. (♀), N. franckei sp. nov. (♂ ♀), N. garnica sp. nov. (♂ ♀), N. gibarrai sp. nov. (♂ ♀), N. irazu sp. nov. (♀), N. iviei sp. nov. (♂), N. ixtlan sp. nov. (♂), N. jiquilpan sp. nov. (♀), N. leonensis sp. nov. (♂ ♀), N. mexiquensis sp. nov. (♂ ♀), N. oaxaca sp. nov. (♂ ♀), N. paricutin sp. nov. (♀), N. perote sp. nov. (♂ ♀), N. plata sp. nov. (♀), N. poncei sp. nov. (♂ ♀), N. popoca sp. nov. (♀), N. prieta sp. nov. (♀), N. puebla sp. nov. (♂ ♀), N. punta sp. nov. (♂ ♀), N. rothi sp. nov. (♂ ♀), N. saltoensis sp. nov. (♀), N. sinaloa sp. nov. (♀), N. tacana sp. nov. (♂ ♀), N. triunfo sp. nov. (♀), N. valdezi sp. nov. (♂ ♀), N. victoria sp. nov. (♀), and N. volcanes sp. nov. (♀). Nine are previously described species: N. annamae (Gertsch & Davis 1940), N. attenuata (F.O. Pickard-Cambridge 1902), N. bipartita (Kraus 1955), N. calavera Chamberlin & Ivie 1942, N. costata (F.O. Pickard-Cambridge 1902), N. laticava (Kraus 1955), N. orizaba (Banks 1898), N. shlomitae (García-Villafuerte 2009), and N. simplex (F.O. Pickard-Cambridge 1902). Four new synonyms are proposed: N. pina Chamberlin & Ivie 1942 = N. intermedia (Chamberlin & Gertsch 1930); N. idahoana (Gertsch 1934) and N. wawona Chamberlin & Ivie 1942 = N. lutzi (Gertsch 1933); N. tolucana (Gertsch & Davis 1940) = N. approximata

  20. Myxomycete diversity of the Patagonian Steppe and bordering areas in Argentina

    Directory of Open Access Journals (Sweden)

    Lado, Carlos

    2014-06-01

    Full Text Available Biodiversity surveys for myxomycetes (Amoebozoa were carried out in three consecutive years (2009 to 2011 in the cold arid Patagonian Steppe, Argentina. The surveys, the first to cover such an extensive area in South America, form part of the Myxotropic project funded by the Spanish Government. Specimens were collected in 174 localities in four different provinces (Neuquén, Río Negro, Chubut and Santa Cruz, between 36° and 52° S latitudes. The most common types of substrate investigated were the dominant shrubs and grasses of the Patagonian steppe, and the Nothofagus forests, characteristic of the transition areas, but other plants such as small cacti and cushion plants were also included in the survey. A total of 133 different species and 5 varieties of myxomycetes representing 31 genera were identified in the 1134 specimens collected either in the field, or from moist chamber cultures prepared with samples of plant material obtained from the same collecting sites. The results include one species new to science, Perichaena nigra, and 17 species and two varieties that were previously unknown for either the Neotropics or South America, Badhamia armillata, Dianema mongolicum, Didymium annulisporum, D. leptotrychum, D. orthonemata, D. sturgisii, Echinostelium coelocephalum, Licea deplanata, L. nannengae, Macbrideola argentea, M. oblonga, Oligonema aurantium, Perichaena luteola, P. madagascariensis, Physarum luteolum, Protophysarum phloiogenum, Trichia contorta var. attenuata, T. contorta var. iowensis, T. erecta. An additional 19 species are new records for Argentina. These additions make Argentina the country in South America, at present, with the greatest number of myxomycetes catalogued having more than 50% of the species cited from the whole Neotropics. Diversity and biogeographic distribution of these organisms are discussed, and taxonomic comments on rare or unusual species are included and illustrated with photographs by LM and SEM. The

  1. Larval fish distribution and their relationship with environmental factors in the southern Tyrrhenian Sea (central Mediterranean during two years of sampling

    Directory of Open Access Journals (Sweden)

    Adriana Profeta

    2014-06-01

    , Vi_a (Vinciguerria attenuata. Fig. 2. Results of CCA analysis for larval fish species and sampled stations during June 2006. Two first axes (CCA1 and CCA2 are represented . Species abbreviations in alphabetical order: Acto_ris (Arctozenus risso, Arno_tho (Arnoglossus thori, Boop_boo (Boops boops, Auxi_roc Cara_acu Cera_mad (Ceratoscopelus maderensis, Cyclo_bra (Cyclothone braueri, Diap_hol (Diaphus holti, Gobi_nig (Gobius niger, Heli_dac (Helicolenus dactylopterus, Hygo_hyg (Hygophum hygomii, Lamp_cro (Lampanyctus crocodilus, Lamp_pus (Lampanyctus pusillus, Lest_jay (Lestidiops jayakari, Myct_pun (Myctophum punctatum, Nezu_aeq (Nezumia aequalis Noto_bol (Notoscopelus bolini, Noto_elo (Notoscopelus elongatus, Para_spe (Paralepis speciosa, Sync_pha (Synchiropus phaeton Spic_sma (Spicara smaris, Trac_tra (Trachurus trachurus.

  2. Antarctic Starfish (Echinodermata, Asteroidea) from the ANDEEP3 expedition

    Science.gov (United States)

    Danis, Bruno; Jangoux, Michel; Wilmes, Jennifer

    2012-01-01

    Abstract This dataset includes information on sea stars collected during the ANDEEP3 expedition, which took place in 2005. The expedition focused on deep-sea stations in the Powell Basin and Weddell Sea. Sea stars were collected using an Agassiz trawl (3m, mesh-size 500µm), deployed in 16 stations during the ANTXXII/3 (ANDEEP3, PS72) expedition of the RV Polarstern. Sampling depth ranged from 1047 to 4931m. Trawling distance ranged from 731 to 3841m. The sampling area ranges from -41°S to -71°S (latitude) and from 0 to -65°W (longitude). A complete list of stations is available from the PANGAEA data system (http://www.pangaea.de/PHP/CruiseReports.php?b=Polarstern), including a cruise report (http://epic-reports.awi.de/3694/1/PE_72.pdf). The dataset includes 50 records, with individual counts ranging from 1-10, reaching a total of 132 specimens. The andeep3-Asteroidea is a unique dataset as it covers an under-explored region of the Southern Ocean, and that very little information was available regarding Antarctic deep-sea starfish. Before this study, most of the information available focused on starfish from shallower depths than 1000m. This dataset allowed to make unique observations, such as the fact that some species were only present at very high depths (Hymenaster crucifer, Hymenaster pellucidus, Hymenaster praecoquis, Psilaster charcoti, Freyella attenuata, Freyastera tuberculata, Styrachaster chuni and Vemaster sudatlanticus were all found below -3770m), while others displayed remarkable eurybathy, with very high depths amplitudes (Bathybiaster loripes (4842m), Lysasterias adeliae (4832m), Lophaster stellans (4752m), Cheiraster planeta (4708m), Eremicaster crassus (4626m), Lophaster gaini (4560m) and Ctenodiscus australis (4489m)). Even if the number of records is relatively small, the data bring many new insights on the taxonomic, bathymetric and geographic distributions of Southern starfish, covering a very large sampling zone. The dataset also brings

  3. Antarctic Starfish (Echinodermata, Asteroidea from the ANDEEP3 expedition

    Directory of Open Access Journals (Sweden)

    Bruno Danis

    2012-04-01

    Full Text Available This dataset includes information on sea stars collected during the ANDEEP3 expedition, which took place in 2005. The expedition focused on deep-sea stations in the Powell Basin and Weddell Sea.Sea stars were collected using an Agassiz trawl (3m, mesh-size 500µm, deployed in 16 stations during the ANTXXII/3 (ANDEEP3, PS72 expedition of the RV Polarstern. Sampling depth ranged from 1047 to 4931m. Trawling distance ranged from 731 to 3841m. The sampling area ranges from -41°S to -71°S (latitude and from 0 to -65°W (longitude. A complete list of stations is available from the PANGAEA data system (http://www.pangaea.de/PHP/CruiseReports.php?b=Polarstern, including a cruise report (http://epic-reports.awi.de/3694/1/PE_72.pdf.The dataset includes 50 records, with individual counts ranging from 1-10, reaching a total of 132 specimens.The andeep3-Asteroidea is a unique dataset as it covers an under-explored region of the Southern Ocean, and that very little information was available regarding Antarctic deep-sea starfish. Before this study, most of the information available focused on starfish from shallower depths than 1000m. This dataset allowed to make unique observations, such as the fact that some species were only present at very high depths (Hymenaster crucifer, Hymenaster pellucidus, Hymenaster praecoquis, Psilaster charcoti, Freyella attenuata, Freyastera tuberculata, Styrachaster chuni and Vemaster sudatlanticus were all found below -3770m, while others displayed remarkable eurybathy, with very high depths amplitudes (Bathybiaster loripes (4842m, Lysasterias adeliae (4832m, Lophaster stellans (4752m, Cheiraster planeta (4708m, Eremicaster crassus (4626m, Lophaster gaini (4560m and Ctenodiscus australis (4489m.Even if the number of records is relatively small, the data bring many new insights on the taxonomic, bathymetric and geographic distributions of Southern starfish, covering a very large sampling zone. The dataset also brings to light

  4. Antarctic Starfish (Echinodermata, Asteroidea) from the ANDEEP3 expedition.

    Science.gov (United States)

    Danis, Bruno; Jangoux, Michel; Wilmes, Jennifer

    2012-01-01

    This dataset includes information on sea stars collected during the ANDEEP3 expedition, which took place in 2005. The expedition focused on deep-sea stations in the Powell Basin and Weddell Sea.Sea stars were collected using an Agassiz trawl (3m, mesh-size 500µm), deployed in 16 stations during the ANTXXII/3 (ANDEEP3, PS72) expedition of the RV Polarstern. Sampling depth ranged from 1047 to 4931m. Trawling distance ranged from 731 to 3841m. The sampling area ranges from -41°S to -71°S (latitude) and from 0 to -65°W (longitude). A complete list of stations is available from the PANGAEA data system (http://www.pangaea.de/PHP/CruiseReports.php?b=Polarstern), including a cruise report (http://epic-reports.awi.de/3694/1/PE_72.pdf).The dataset includes 50 records, with individual counts ranging from 1-10, reaching a total of 132 specimens.The andeep3-Asteroidea is a unique dataset as it covers an under-explored region of the Southern Ocean, and that very little information was available regarding Antarctic deep-sea starfish. Before this study, most of the information available focused on starfish from shallower depths than 1000m. This dataset allowed to make unique observations, such as the fact that some species were only present at very high depths (Hymenaster crucifer, Hymenaster pellucidus, Hymenaster praecoquis, Psilaster charcoti, Freyella attenuata, Freyastera tuberculata, Styrachaster chuni and Vemaster sudatlanticus were all found below -3770m), while others displayed remarkable eurybathy, with very high depths amplitudes (Bathybiaster loripes (4842m), Lysasterias adeliae (4832m), Lophaster stellans (4752m), Cheiraster planeta (4708m), Eremicaster crassus (4626m), Lophaster gaini (4560m) and Ctenodiscus australis (4489m)).Even if the number of records is relatively small, the data bring many new insights on the taxonomic, bathymetric and geographic distributions of Southern starfish, covering a very large sampling zone. The dataset also brings to light six

  5. Vegetation-induced soil water repellency as a strategy in arid ecosystems. A geochemical approach in Banksia woodlands (SW Australia)

    Science.gov (United States)

    Muñoz-Rojas, Miriam; Jiménez-Morillo, Nicasio T.; González-Pérez, Jose Antonio; Zavala, Lorena M.; Stevens, Jason; Jordan, Antonio

    2016-04-01

    Introduction Banksia woodlands (BW) are iconic ecosystems of Western Australia (WA) composed by an overstorey dominated by Proteaceae, e.g. Banksia menziesii and Banksia attenuata, in combination with other species, such as Eucalyptus spp., Verticordia spp. or Melaleuca spp. Although located in very poor dune soils, BW provide numerous ecosystem services and sustain a high biodiversity. In this area, annual rainfall is relatively high (about 800 mm) but permeability of the sandy substrate leads to a functionally arid ecosystem. Currently, BW are threatened by sand mining activities and urban expansion; therefore conservation and restoration of these woodlands are critical. Despite numerous efforts, the success of restoration plans is usually poor mostly due to the high sensitivity to drought stress and poor seedling survival rates (5-30%) (Benigno et al., 2014). A characteristic feature of BW is their root architecture, formed by a proteoid (cluster) system that spreads to form thick mats below the soil surface, favouring the uptake of nutrients (especially, P), and preventing soil erosion. Root exudates are related to numerous plant functions, as they facilitate penetration of roots in soil and enhance the extraction of scarce mineral nutrients and its further assimilation. Exudates may also interact directly with soil or indirectly through microbial mediated events being also related to soil water repellency (SWR; Lozano et al, 2014). Knowledge about the specific compounds able to induce SWR is limited (Doerr et al., 2000), but it is generally accepted that is caused by organic molecules coating the surface of soil mineral particles and aggregates (Jordán et al., 2013). Proteaceae release short-chained organic acids to enhance phosphate acquisition, which have been also reported to be related with SWR (Jiménez-Morillo et al., 2014). It is hypothesized that disruption of water dynamics in mature BW soils is underlying the failure of restoration plans. This

  6. Population dynamics and monitoring applied to decision-making

    Directory of Open Access Journals (Sweden)

    Conroy, M. J.

    2004-06-01

    influence diagrams to capture the stochastic, temporal processes of managing cheetah population in Kenya. The model predicts likely anagement decisions made by various actors within these countries, (e.g., the President, the Environmental Protection Agency, and rural residents and the resulting probability of cheetah extinction following these decisions. By approaching the problem in both its political and ecological contexts one avoids consideration of decisions that, while beneficial from a purely conservation point of view, are unlikely to be implemented because of conflicting political objectives. Haas’s analysis demonstrates both the promise and challenges of this type of modeling, and he offers suggestions for overcoming inherent technical difficulties such as model calibration. The second paper, by Simon Hoyle and Mark Maunder (Hoyle & Maunder, 2004, uses a Bayesian approach to model population dynamics and the effects of commercial fishing bycatch for the eastern Pacific Ocean spotted dolphin (Stenella attenuata. Their paper provides a good example of why Bayesian analysis is particularly suited to many management problems. Namely, because it allows the integration of disparate pieces of monitoring data in the simultaneous estimation of population parameters; allows forincorporation of expert judgment and data from other systems and species; and provides for explicit consideration of uncertainty in decision–making. Alternative management scenarios can then be explored via forward simulations. In the third paper, Chris Fonnesbeck and Mike Conroy (Fonnesbeck & Conroy, 2004 present an integrated approach for estimating parameters and predicting abundance of American black duck (Anas rubripes populations. They also employ a ayesian approach and overcome some of the computational challenges by using Markov chain–Monte Carlo methods. Ring–recovery and harvest data are used to estimate fall age ratios under alternative reproductive models. These in turn are used to