Degradação de diquat em condições de caixa d'água com e sem plantas de egéria

Egeria is considered to be the most important aquatic weed in Brazilian reservoirs since it causes great damage to navigation, fishing and power generation. The objective of this work was to study diquat degradation under small-tank conditions with and without Egeria densa and Egeria najas and in so...

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Detalles Bibliográficos
Autores: Negrisoli, E. [UNESP], Martins, D. [UNESP], Velini, D.e. [UNESP], Ferrera, W.l.b.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2003
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:portugués
OAI Identifier:oai:repositorio.unesp.br:11449/211255
Acceso en línea:http://dx.doi.org/10.1590/S0100-83582003000400014
http://hdl.handle.net/11449/211255
Access Level:acceso abierto
Palabra clave:aquatic weed
half-life
herbicide
planta aquática
meia-vida
herbicida
Descripción
Sumario:Egeria is considered to be the most important aquatic weed in Brazilian reservoirs since it causes great damage to navigation, fishing and power generation. The objective of this work was to study diquat degradation under small-tank conditions with and without Egeria densa and Egeria najas and in soil. This trial was carried out at Unesp (Brazil), 1999. The plots consisted of reservoirs with 300-liter water capacity, plus 20 cm soil and 5 cm sand on the bottom. Twenty branches of each Egeria species were planted. The treatments consisted of applying 6 ppm diquat (Reward) under three different conditions: (i) reservoirs with water only, (ii) reservoirs with water and soil, and (iii) reservoirs with water plant and soil. The concentration was measured spectrophotometrically (308 nm), obtaining the following curve: herbicide concentration (ppm) = 0.7418 + 50.95391* A, where A= absorbance reading. The correlation coefficient was 0,9956648. Diquat half-life was 29 days after application, under condition (iii). Under condition (ii) Diquat half-life was 23 days after application. Under condition (i) its half-life was 18 days after application.