Browsing by Author "6805cc70-f0a6-4e1f-9f8a-c6a4b6ee7b8d"
Now showing items 21-40 of 90
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Bravo, Héctor R.; Niemeyer, Hermann M. (1985)The decomposition of the title compound (DIMBOA, 1) in aprotic solvents was analysed in terms of linear solvation energy relationships using donor numbers. The results indicate rate-limiting cyclic hemiacetal opening in ...
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Bravo, Héctor R.; Niemeyer, Hermann M. (1991)Kinetic and product studies indicate that the title compound decomposes in aqueous solutions to give 5-nitro-2-aminophenol with the intermediacy of N-(2-hydroxy-4-nitrophenyl)carbamic acid. © 1991.
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Collantes, Hugo G.; Gianoli, Ernesto; Niemeyer, Hermann M. (Kluwer Academic/Plenum Publishers, 1999)The effect of defoliation and consecutive defoliation (condefoliation) of rye seedlings on the allocation patterns of biomass and hydroxamic acids (Hx) was evaluated five days after treatment. Growth of condefoliated ...
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Pinto, Carlos F.; Torrico Bazoberry, Daniel; Flores Prado, Luis; Bustamante Araya, Ramiro; Niemeyer, Hermann M. (Elsevier, 2020)The mechanisms which promote divergence in populations of phytophagous insects using alternative hosts depend on the characterization of hosts as different selective scenarios and the modeling of the demographic dynamics ...
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Gianoli, Ernesto; Niemeyer, Hermann M. (Kluwer Academic Publishers, 1998)Hydroxamic acids are secondary metabolites typical of Poaceae that play a role in cereal resistance against pests and pathogens. The content of the hydroxamic acid aglucones DIBOA (2,4-dihydroxy-1,4-benzoxazin-3-one) and ...
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Macel, Mirka; Bruinsma, Maaike; Dijkstra, Sander M.; Ooijendijk, Tessa; Niemeyer, Hermann M.; Klinkhamer, Peter G.L. (2005)The evolution of the diversity in plant secondary compounds is often thought to be driven by insect herbivores, although there is little empirical evidence for this assumption. To investigate whether generalist insect ...
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Valdivia, Carlos E.; Niemeyer, Hermann M. (2006)Pollination syndromes lead to questions concerning the role of different suites of pollinators on the pollination success of plants. Escallonia myrtoidea exhibits floral traits associated with pollination by diurnal ...
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Argandoña, Victor H.; Niemeyer, Hermann M.; Corcuera, Luis J. (1981)The content of hydroxamic acids in wheat plants shows substantial variations between different species and cultivars (1.0-6.3 mmol/kg fr. wt). It also varies with the age of the plant and the organ assayed. The maximum ...
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Argandon̄a, Victor H.; Pen̄a, Gabriel F.; Niemeyer, Hermann M.; Corcuera, Luis J. (1982)Toxicity of DIMBOA, the major cyclic hydroxamic acid in maize extracts, to the aphid Schizaphis graminum, was decreased by addition of cysteine to the insect diet. The ld50 for DIMBOA on aphids was, after 24 hr, 2.1 and ...
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Martos, Agustin; Givovich, Arturo; Niemeyer, Hermann M. (Kluwer Academic Publishers-Plenum Publishers, 1992)DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one), a secondary metabolite found in cereal extracts, confers resistance in wheat to aphids. Its effect on beneficial organisms was tested on larvae of the aphid predator ...
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Figueroa, Christian C.; Simon, Jean Christophe; Le Gallic, Jean Francois L.E.; Prunier-Leterme, Nathalie; Briones, Lucia M.; Dedryver, Charles Antoine; Niemeyer, Hermann M. (2004)Five microsatellite loci were used to study the genetic variability and population structure of Sitobion avenae (Hemiptera: Aphididae) on some of its host plants. Individuals were collected in Chile from different cultivated ...
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Cuevas, Liliana; Niemeyer, Hermann M. (1993)2,4-Dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), a hydroxamic acid involved in the resistance of wheat to the aphid Rhopalosiphum padi, and known to react with serine and cysteine residues, inactivated acylcholinesterases ...
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Rodríguez, Luis C.; Fuentes-Contreras, Eduardo; Niemeyer, Hermann M. (Czech Academy of Sciences, 2002)The aphid parasitoid Aphidius ervi was collected and subsequently reared on Sitobion avenae on wheat or Acyrthosiphon pisum on alfalfa. Parasitoids from both origins were exposed in an olfactometer to alfalfa or wheat ...
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Ramírez, Claudio C.; Caballero, Paula P.; Niemeyer, Hermann M. (Kluwer Academic/Plenum Publishers, 1999)We hypothesized that aphids after previous exposure to hydroxamic acids (Hx), a family of secondary plant compounds deleterious to aphids, are able to reduce their subsequent exposure to them. This hypothesis was tested ...
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Loayza-Muro, Raúl; Figueroa, Christian C.; Niemeyer, Hermann M. (2000)Hydroxamic acids (Hx) are wheat secondary metabolites conferring resistance for cereals against aphids. The activity of five enzymatic systems were evaluated in the aphid Sitobion avenae reared on the high-Hx wheat cultivar ...
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Fuentes-Contreras, Eduardo; Niemeyer, Hermann M. (2000)The influence of wheat (Triticum aestivum L.) resistance, the parasitoid Aphidius rhopalosiphi De Stephani-Perez (Hymenoptera: Braconidae) and the entomopathogenic fungus Pandora neoaphidis (Remaudiere et Hennebert) Humber ...
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Castañeda, Luis E.; Figueroa, Christian C.; Fuentes-Contreras, Eduardo; Niemeyer, Hermann M.; Nespolo, Roberto F. (2009)Herbivorous insects have developed mechanisms to cope with plant barriers, including enzymatic systems to detoxify plant allelochemicals. Detoxification systems may be induced when insects are feeding on plants with ...
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Gianoli, Ernesto; Niemeyer, Hermann M. (Springer New York LLC, 1997)The effects of temperature and photoperiod on accumulation of hydroxamic acids (Hx) in wheat (Triticum aestivum L.) seedlings were evaluated under laboratory conditions. Hx concentrations were significantly higher at higher ...
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Gianoli, Ernesto; Niemeyer, Hermann M. (Springer Verlag, 1996)The effects of temperature and photoperiod on the ability of wheat (Triticum aestivum L.) seedlings to show induced responses (increased accumulation of hydroxamic acids, Hx) upon infestation by the bird cheery-oat aphid. ...
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Echeverría, Javier; Niemeyer, Hermann M. (Taylor and Francis Ltd., 2017)© 2016 Informa UK Limited, trading as Taylor & Francis Group. The chemical composition of the essential oil of Kurzamra pulchella (Lamiaceae) was determined. Twelve compounds were identified, with isomenthone (60.6%) and ...