937 research outputs found

    Consumption to biomass (Q/B) ratio and estimates of Q/B-predictor parameters for Caribbean fishes

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    Estimates of the Q/B ratio and parameters of equations to 'predict' Q/B values for 116 fish stocks in the Gulf of Salamanca, Colombia are presented. A compilation of these estimates available for Caribbean Sea fishes (264 stocks) is also provided for comparison purposes. General trends in the value of Q/B resulting from differences in the equation and parameter values used are briefly discussed

    Length-weight relationships of demersal fishes from the upper continental slope off Colombia

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    Parameters of the length–weight relationship of the form W=aLb are presented for 45 demersal fish species caught on the upper continental slope of the Caribbean Sea off Colombia. The b values varied between 2.13 and 4.97, with the mean b = 3.042 (95% CI, 2.887- 3.196)

    On univalence and P-matrices

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    AbstractSuppose F is a differentiable mapping from a rectangle R⊂En into En. Gale and Nikaido proved that if the Jacobian of F is a P-matrix in R, then F is univalent in R. Their paper has served as the basis of numerous results on univalence. Recently H. Scarf conjectured a significant extension: that the Jacobian of F need not be a P-matrix everywhere in the rectangle R, but merely on its boundary. This paper proves Scarf's conjecture, and to do so utilizes a conceptually different method of proof than that of Gale and Nikaido. The proof is presented in such a way as to demonstrate a suggestion of Scarf that orientation arguments may provide an alternative proof of the Gale-Nikaido theorem

    Effect Of Soil Management On The White Grub Population And Damage In Soybean

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    To evaluate the effect of soil management systems on population of white grubs, (Phyllophaga cuyabana Moser), and on its damage in soybean, experiments were set up under no-tillage and conventional tillage (one disk plow, and a leveling disk harrow) areas. Primary tillage equipment, used in other soil management systems, such as moldboard plow, disk plow, chisel plow and heavy duty disk harrow were also tested. Fluctuation of P. cuyabana population and the extent of its damage to soybean was similar under no-tillage and conventional tillage systems. Results comparing a range of primary tillage equipment showed that it affected soil insect populations differently, depending on the time during the season in which tillage was executed. Larval mortality could mostly be attributed to their exposure to adverse factors, soon after tillage, than to changes in soil conditions. Reduction of white grub population was more evident in plots managed by heavier equipment, such as the moldboard plow. Soil tillage could be one component within the soil pest management system in soybean, however, its use can not be generalized.355887894Alvarado, L., (1979) Comparación Poblacional de "Gusanos Blancos" (Larvas de Coléopteros Scarabaeidae) en Tres Situaciones de Manejo, 5p. , Pergamino : INTA/ EERA, (INTA/EERA. Genéralidades Carpeta de Producción Vegetal. Información, 16)Brown, W.R., Gange, A.C., Insect herbivore below ground (1990) Advances in Ecological Research, 20, pp. 1-58. , San DiegoGarcia, M.A., Arthropods in tropical corn field: Effects of woods and insecticides on community composition (1991) Plant-animal Interactions: Evolutionary Ecology in Tropical and Temperate Regions, pp. 619-634. , PRICE, P.LEWINSOHON, T.M.FERNANDES, W.BENSON, W.W. (Eds.). New York: J. WileyGassen, D.N., Corós associados ao sistema de plantio direto (1993) Plantio Direto no Brasil, pp. 141-149. , ALDEIA NORTE (Passo Fundo, RS) (Ed.). Passo Fundo : Embrapa-CNPT/Fundacep Fecotrigo/Fundação ABCHammond, R.B., Stinner, B.R., Seedcom maggots (Diptera: Anthomyiidae) and slugs in conservation tillage systems in Ohio (1987) Journal of Economic Entomology, 80, pp. 680-684. , LanhamHoffmann-Campo, C.B., Parra, J.R.P., Mazzarin, R.M., Ciclo biológico de Sternechus subsignatus Boheman, 1836 (Coleoptera: Curculionidae) em soja no norte do Paraná (1991) Revista Brasileira de Biologia, 51, pp. 615-621. , Rio de Janeiro(1976) Manual Agropecuário para O Paraná, 1. , LondrinaOliveira, L.J., (1997) Ecologla Comportamental e de Interações com Plantas Hospedeiras em Phyllophaga Cuyabana (Moser) (Coleoptera: Melolonthidae, Melolonthinae) e Implicações para o Seu Manejo em Cultura de Soja, 148p. , Campinas : Unicamp, Tese de DoutoradoOliveira, L.J., Hoffmann-Campo, C.B., Do Amaral, M.L.B., Nachi, C., (1992) Coró Pequeno da Soja, 4p. , Londrina : Embrapa-CNPSo. (Embrapa-CNPSo. Documentos, 51)Oliveira, L.J., Hoffmann-Campo, C.B., Sistemas de preparo de solo: Efeito sobre populações de larvas de escarabeídeos e Sternechus subsignatus (1996) Resultados de Pesqulsa de Soja 1990/91, pp. 464-468. , EMBRAPA. Centro National de Pesquisa de Soja (Londrina, PR). Londrina, (Embrapa-CNPSo. Documentos, 99)Rincón, M.B.N., Tiscareño, M., Velásquez, M., Diversidad y abundancia de Melolonthidae y Scarabaeidae (Insecta: Coleoptera) asociados a diferentes sistemas de labranza y porcentajes de cobertura vegetal en agrosistemas de maíz del Estado de Michoacan, México (1997) Reunión Latino-americana de Escara-beidologia, 3, pp. 18-19. , Xalapa. Memórias. Xalapa: Institute de Ecologia, 1997Shelton, M.D., Edwards, C.R., Effects of weeds on the diversity and abundance of insects on soybeans (1983) Environmental Entomology, 12, pp. 296-298. , LanhamDa Silva, M.T.B., Grutzmacher, A.D., Ruedell, J., Link, D., Costa, E.C., Influência de sistemas de manejo de suelos y de culturas sobre insectos sub́terraneos (1994) Clência Rural, 24, pp. 247-251. , Santa MariaDa Silva, M.T.B., Klein, V.A., Efeito de diferentes métodos de preparo do solo na infestação e danos de Sternechus subsignatus (Boheman) em soja (1997) Ciência Rural, 27, pp. 533-536. , Santa MariaDa Silva, M.T.B., Klein, V.A., Link, D., Reinert, D.J., Influência de sistemas de manejo de solos na oviposição de Diloboderus abderus Sturm (Coleoptera: Melolonthidae) (1994) Anais da Sociedade Entomológica Brasileira, 3, pp. 543-548. , LondrinaSloderbeck, P.E., Yeargen, K.V., Green cloverworm (Lepidoptera: Noctuidae) populations in conventional and double-cropped, no-till soybeans (1983) Journal of Economic Entomology, 76, pp. 785-791. , LanhamSmith, A.W., Hammond, R.B., Stinner, B.R., Influence of rye-cover crop management on soybean foliage arthropods (1988) Environmental Entomology, 17, pp. 109-114. , LanhamStinner, B.R., House, G.J., Arthropods and other invertebrates in conservation-tillage agriculture (1990) Annual Review of Entomology, 35, pp. 299-318. , Palo AltoStrnad, S.P., Bergman, M.K., Movement of first-instar western corn rootworms (Coleoptera: Chrysomelidae) in soil (1987) Environmental Entomology, 16, pp. 975-978. , LanhamToxclair Jr., N.N., Boethel, D.J., The influence of tillage practices and row spacing on soybean insect populations in Louisiana (1984) Journal of Economic Entomology, 77, pp. 1571-1579. , LanhamWinter, J.P., Voroney, R.P., Ainsworth, D.A., Soil microarthropods in long-term no-tillage and conventional tillage corn production (1990) Canadian Journal of Soil Science, 70, pp. 641-653. , Ottaw

    Effect of soil management on the white grub population and damage in soybean.

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    To evaluate the effect of soil management systems on population of white grubs, (Phyllophaga cuyabana Moser), and on its damage in soybean, experiments were set up under no-tillage and conventional tillage (one disk plow, and a leveling disk harrow) areas. Primary tillage equipment, used in other soil management systems, such as moldboard plow, disk plow, chisel plow and heavy duty disk harrow were also tested. Fluctuation of P. cuyabana population and the extent of its damage to soybean was similar under no-tillage and conventional tillage systems. Results comparing a range of primary tillage equipment showed that it affected soil insect populations differently, depending on the time during the season in which tillage was executed. Larval mortality could mostly be attributed to their exposure to adverse factors, soon after tillage, than to changes in soil conditions. Reduction of white grub population was more evident in plots managed by heavier equipment, such as the moldboard plow. Soil tillage could be one component within the soil pest management system in soybean, however, its use can not be generalized

    Tarpon atlanticus in Colombia: a big fish in trouble

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    The natural history of Tarpon atlanticus (Valenciennes 1846) is reconstructed based on published information. Tarpon is a remarkable fish because of its peculiar larvae, large adult size, migration patterns and its capability to breathe atmospheric air. Destructive fisheries - some using dynamite - have much reduced the population of tarpon along the Caribbean coast of Colombia, and some catch data are presented which document this

    Comparison of local pole assignment methods

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76770/1/AIAA-20171-818.pd

    Feeding And Oviposition Preference Of Phyllophaga Cuyabana (moser) (coleoptera: Melolonthidae) On Several Crops

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    Laboratory and greenhouse experiments were carried out to study food and oviposition preference by Phyllophaga cuyabana (Moser) on different plant species as Cajanus cajan L. (pigeon pea), Crotalaria juncea L. (sun hemp), Crotalaria spectabilis Roth (showy crotalaria), Crotalaria ochroleuca G. Don (slenderleaf rattlebox), Glycine max [L.] Merrill (soybean), Gossypium hirsutum L. (cotton), Helianthus annuus L. (sunflower), Stizolobium aterrimum [Mucuna aterrima] Piper & Tracey (velvetbean) and Zea mays L. (mayze). In no-choice experiments, the number of eggs layed in sunflower, C. juncea and soybean was larger compared to cotton. Despite the fact that the adults did not discriminate among plants, in dual-choice test, the proportion of eggs layed and leaf consumption by P. cuyabana adults in soybean were significantly higher than in C. spectabilis. The larval distribution in the soil was at random in multiple-choice, withouth any trend of preference, but in dual-choice, when soybean was the control, larvae always preferred to feed on its roots. P. cuyabana adults had preference for more suitable hosts and that could stand their offspring survival. This behaviour can be usefully exploited in an integrated management program for this pest.365759764Craig, T.P., Itami, J.K., Price, P.W., A strong relationship between oviposition preference and larval performance in a shoot-galling sawfly (1989) Ecology, 70, pp. 1691-1699Diagne, A. 2004. Seasonal occurrence of Phyllophaga species and biological studies of Phyllophaga ephilida (Say) on sweet potato, Ipomoea batatas (1) Lam, in Louisiana. PhD thesis, Louisiana State University and Agricultural and Mechanical College, Baton Rouge, 101pMoron, M.A., (1986) El genero Phyllophaga en México: Morfología, distribución y sistematica supraespecifica, , México, Instituto de Ecología, 341pOliveira, L.J., B. Santos, J.R.P. Parra & C.B. Hoffmann-Campo. 2004. Coró-da-soja, p.151-176. In J.R. Salvadori, C.J. Ávila & M.T.B. da Silva (org.), Pragas de solo no Brasil. Passo Fundo, Embrapa Trigo, Embrapa Agropecuária Oeste, Fundacep, 541pOliveira, L.J., Garcia, M.A., Flight, feeding and reproductive behaviour of Phyllophaga cuyabana (Moser) (Coleoptera: Melolonthidae) adults (2003) Pesq. Agropec. Bras, 38, pp. 179-186Potter, D.A., Held, D.W., Biology and management of the Japanese beetle (2002) Annu. Rev. Entomol, 47, pp. 175-205Silva, M.T.B. da & J.R. Salvadori. 2004. Coró-das-pastagens, p.191-210. In J.R. Salvadori, C.J. Ávila & M.T.B. da Silva (org.), Pragas de solo no Brasil. Passo Fundo, Embrapa Trigo, Embrapa Agropecuária Oeste, Fundacep, 541pSilva, da, M.T.B., Tarragó, M.F.S., Link, D., Costa, E.C., Preferência de oviposição de Diloboderus abderus (Sturm) por restos de culturas em solo com plantio direto (1996) An. Soc. Entomol. Brasil, 25, pp. 83-87Rausher, M.D., Alteration of oviposition behaviour by Battus philenor butterflies in response to variation in host-plant density (1983) Ecology, 64, pp. 1028-1034Thompson, H.N., Evolutionary ecology of the relationship between oviposition preference and performance of offspring in phytophagous insects (1988) Entomol. Exp. Appl, 47, pp. 3-14Travis, B.V., Habits of the June beetle, Phyllophaga lanceolata (Say), in Iowa (1939) J. Econ. Entomol, 32, pp. 690-69

    Length-weight relationships of demersal fishes from the Gulf of Salamanca, Colombia: [part 2]

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    The parameters a and b of the length-weight relationship of the form W=aL super(b) are presented for 37 fish species, belonging to 17 families, caught during a demersal trawl survey over the period December 1995 to March 1998 in the Gulf of Salamanca, Colombi

    Search for the Proton Decay Mode proton to neutrino K+ in Soudan 2

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    We have searched for the proton decay mode proton to neutrino K+ using the one-kiloton Soudan 2 high resolution calorimeter. Contained events obtained from a 3.56 kiloton-year fiducial exposure through June 1997 are examined for occurrence of a visible K+ track which decays at rest into mu+ nu or pi+ pi0. We found one candidate event consistent with background, yielding a limit, tau/B > 4.3 10^{31} years at 90% CL with no background subtraction.Comment: 13 pages, Latex, 3 tables and 3 figures, Accepted by Physics Letters
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