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Search Results: 1 - 10 of 327828 matches for " Jerson V.C.;Kruse "
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Plantas infestantes hospedeiras de Rhopalosiphum rufiabdominalis (Sasaki) (Hemiptera: Aphididae) em áreas de cultivo de arroz irrigado
Maziero, Heleno;Guedes, Jerson V.C.;Kruse, Nelson D.;Farias, Juliano R.;
Neotropical Entomology , 2007, DOI: 10.1590/S1519-566X2007000300017
Abstract: rhopalosiphum rufiabdominalis (sasaki) is an insect of world-wide distribution that damages irrigated rice. from september, 2004 to february, 2005, nymphs and adults of this aphid were collected in several host weeds of rice farms in alegrete, quaraí and uruguaiana, located in western of state of rio grande do sul, and restinga seca, in central region of this state, brazil. the insect was found in the root of andropogon bicornis (west indian foxtail), echinochloa colona (jungle rice), oryza sativa (volunteer rice and red-rice), paspalum sp. (paspalum) and soliva pterosperma (lawn burweed).
Aspectos biológicos do período embrionário dos curculionídeos-das-raízes dos citros
Guedes, Jerson V.C.;Parra, José R.P.;
Neotropical Entomology , 2007, DOI: 10.1590/S1519-566X2007000200004
Abstract: the goal of this work was to study some characteristics of the egg phase of three species of citrus root weevils. the insects were collected from citrus plants in itapetininga, sp, and brought to the laboratório de biologia de insetos of esalq/usp, in piracicaba, sp, where the species naupactus cervinus (boheman), naupactus versatilis (hustache) and parapantomorus fluctuosus (boheman) were kept. duration and viability of the egg phase were evaluated, and the lower temperature threshold and thermal constant (k) were calculated for these species. the species of citrus root weevils showed different duration of egg phases. the egg phase ranged from 40.4 to 13.8 n. cervinus, from 38.7 to 20.0 days for n. versatilis, and from 35.0 to 13.8 days for p. fluctuosus, depending upon temperature. the temperature thresholds of this stage were 8.1, 8.3, and 9.9oc at thermal constant was 385.7, 397.7 and 294.1 degree-days, for n. cervinus, n. versatilis and p. fluctuosus respectively. the duration of the egg phases of n. cervinus and n. versatilis were similar at the same temperatures and p. fluctuosus had a faster development than naupactus spp. in all temperatures tested.
ácaros associados à cultura da soja no Rio Grande do Sul
Guedes, Jerson V.C.;Navia, Denise;Lofego, Antonio C.;Dequech, S?nia T.B.;
Neotropical Entomology , 2007, DOI: 10.1590/S1519-566X2007000200017
Abstract: during the last growing seasons, high infestations of phytophagous mites were observed in the state of rio grande do sul, brazil, becoming necessary to apply pesticides for their control. the objective of this study was to identify phytophagous and predatory mite species associated with soybean in ten counties of that state, during the 2002/03 and 2003/04 growing seasons, in five soybean cultivars (a 6001 rg, a 7001 rg, a 8000 rg, a 8100 rg, anta 82), all genetically modified. in samples of soybean leaves four phytophagous mite species (mononychellus planki (mcgregor), polyphagotarsonemus latus (banks), tetranychus desertorum banks and tetranychus gigas pritchard & baker) and two predatory mite species (phytoseiulus fragariae denmark & schicha and typhlodromalus aripo de leon) were found. t. desertorum was found for the first time associated with soybean in the country. phytoseiulus fragariae and t. aripo are reported for the first time on soybean. the potential of phytoseid mites as biological control agents in soybean crop was discussed. among the hypotheses to explain the increasing infestation of soybean fields with phytophagous mites area are the progressively larger cultivated area, the dry spells observed in the last few years in the growing season, changes in soybean cropping system that led to increased use of pesticides and utilization of new soybean cultivars with morphological or biochemicals characteristics that favour the development of these mite populations.
Ocorrência de Rachiplusia nu (Guenée) (Lepidoptera: Noctuidae) em fumo (Nicotiana tabacum L.) no Rio Grande do Sul
Specht, Alexandre;Guedes, Jerson V.C.;Sulzbach, Felipe;Vogt, Tatiane G.;
Neotropical Entomology , 2006, DOI: 10.1590/S1519-566X2006000500020
Abstract: the occurrence of rachiplusia nu (guenée) is registered for the first time in tobacco [nicotiana tabacum l. (solanaceae)]. the specimens were collected in a virginia tobacco field, in venancio aires, state of rio grande do sul. caterpillars occurred in large infestations, causing important damage to tobacco leaves, and demanding chemical control to minimize losses. this occurrence indicates that this species can feed on virginia tobacco, which corresponds to 80% of the tobacco area of rio grande do sul, and so presents high risk to become an important pest in tobacco fields.
Chave de identifica??o, ocorrência e distribui??o dos curculionídeos-das-raízes dos citros em S?o Paulo e Minas Gerais
Guedes, Jerson V.C.;Lanteri, Analia A.;Parra, José R.P.;
Neotropical Entomology , 2005, DOI: 10.1590/S1519-566X2005000400007
Abstract: the objective of this paper is to bring about a diagnosis of four species of root weevils, recorded for the first time causing damage in citrus grooves of the states of s?o paulo and minas gerais, brazil. a key for the identification of 14 species harmful for citrus in these states is provided as well as a study on their occurrence and distribution. the four species treated in this paper belong to the genus naupactus dejean (curculionidae: entiminae: naupactini): n. bellus boheman, n. cinerosus boheman; n. decorus (fabricius) and n. virens boheman. among the 14 species included in the key, eleven belong to naupactus [n. ambiguus boheman, n. bellus boheman, n. cervinus boheman, n. cinerosus boheman; n. curtus boheman, n. decorus (fabricius), n. navicularis boheman, n. rivulosus (olivier), n. tarsalis boheman, n. versatilis hustache and n. virens (boheman); one to teratopactus heller (t. nodicollis (boheman)]; one to parapantomorus emden [p. fluctuosus (boheman)] and one to symmathetes (s. kollari schoenherr). the citrus root weevils occur in all citrus grooves of s?o paulo and minas gerais, and the species diversity is higher in the center-south area of s?o paulo. n. tarsalis, n. versatilis and p. fluctuosus are present in the highest number of localities.
A determina??o do nitrato em extratos de planta e de solos pelo método de absor??o no ultra-violeta
Bittencourt, V.C.;
Anais da Escola Superior de Agricultura Luiz de Queiroz , 1969, DOI: 10.1590/S0071-12761969000100005
Abstract: nitrate in soils and plants can be determined by the method of ultraviolet absorption of nitrowyl chloride. the extracts of plants need to be treated with hydrogen peroxide before the determination in order to exidize the organic matter. for the soil extracts the blank is obtained by eliminating nitrates with hydrazine sulfate wich server to correct the absorption of the soil solutions. the determination is carried on adding perchloric, sulfuric and hudrochloric acids to the solutions obtained from vegetable and soil materials to form nitrowyl chloride. the absorbances of solutions are read at 230 miliraicrons.
the Mq-scf quantum approach of the p-azoxyanisole (PPa) molecule i. quantum energetic molecular characteristics
V.C. Scridonesi
Analele Universitatii Bucuresti : Chimie , 2005,
Abstract: For the first time in the literature of the liquid crystals (LC) a molecule LC type (pazoxyanisole(PPA)) is approached by means of the nonrelativistic molecular quantummechanics. The structural complexity of the quantum molecular system (33 nuclei, 196electrons) imposes a MO-SCF-LCAO/CNDO quantum approach, having at its basis the Hartree-Fock-Roothaan equations with LCAO expansion of the molecular orbitals (MO) and with PPPparameters of the approximation used. The quantum computations have been performed in theCNDO-2 approximation, using a computing program of MO-SCF type. For the PAA moleculethe following quantum energetic characteristics have been obtained: the orbital energies, the totalelectronic energy, the total molecular energy, the bonding energy, the ionization potential, thereduction potential (or the affinity of electrons) and the width of the forbidden interorbital zone.The quantum results related in this paper are interpreted and discussed for the PAA molecule ofthe nematic LC class.
V.C. Muller
Scientia Militaria : South African Journal of Military Studies , 2012, DOI: 10.5787/10-4-696
Abstract: This scenario of the Third World War depicts the events leading to the war, the conflict itself, and the aftermath. Purporting to be a history, complete with appendices, maps and index, of a war recently ended, the overall tone of the book gives the impression that it might have been derived from one or more war games.
Warning and Response
V.C. Muller
Scientia Militaria : South African Journal of Military Studies , 2012, DOI: 10.5787/11-2-660
Abstract: Julian Critchley is the Conservative MP for Aldershot. Although the subtitle of the book reads: 'A study of surprise attack in the 20th century and an analysis of its lessons for the future,' and although the author illustrates his thesis by citing examples of surprise attack in the various wars since 1939, the essence of this work is concern for the Central European front of NATO. For years, NATO'S plans have been based on the assumption that there would be a period of warning resulting from the deterioration of the international situation and overt activity on the part of the Warsaw Pact forces. Critchley examines the ability of NATO to predict and to respond to the Soviet - Warsaw Pact threat; he believes that NATO's defence must be credible without reliance upon warning, that warning signs are invariably misinterpreted, disbelieved and filtered by the preconceptions of the politicians. Not even the ability to read the enemy's codes is a guarantee of learning his intentions. He concludes that the warning of attack is bound to be ambiguous and suggests that in order to prevent war NATO must restore tactical nuclear deterrence in Europe.
AMERICAN CAESAR: Douglas MacArthur, 1880-1964
V.C. Muller
Scientia Militaria : South African Journal of Military Studies , 2012, DOI: 10.5787/10-2-712
Abstract: The narrative begins on a hilltop in Tennessee in 1863. It is Missionary Ridge where 18-year-old Lt Arthur MacArthur, the father of Douglas MacArthur, won the Medal of Honour. Arthur, who later became a Lieutenant General, was the driving spirit behind Douglas throughout his career.
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