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Publicação
Resistências cruzadas em biótipos de alisma plantago-aquatica resistentes ao bensulfurão-metilo e suas consequências
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Orientador(es)
Resumo(s)
The repetitive use of bensulfuron-methyl
in rice fields from Sorraia, Sado and Mondego
river valleys had selected resistant (R)
populations of Alisma plantago-aquatica in
Portugal, identified as So306, So307, Sa88,
Mo190; Mo260, respectively. The response of
R-biotypes to bensulfuron-methyl at 26 days
after seeding (DAS) and 42 DAS and the cross-resistance either to ALS- inhibitors or to
herbicides with other mode of action, was
investigated in dose-response experiments.
The results confirmed bensulfuron-methyl
resistance in four biotypes, but not in Mo190,
which had been also treated with bentazon
every year. Younger plants (6 linear phyllodium,
BBCH 116) were more susceptible to
bensulfuron-merthyl than were older plants (6
expanded phyllodium, BBCH 126). Rbiotypes
presented cross-resistance to all ALSinhibitors
studied except for imazethapyr and
metsulfuron-methyl. Resistance indeces (RI=
ED50R /ED50 S) ranged frome 3 to 313 for the
three sulfonylurea herbicides. Herbicides with
different mode of action including bentazon,
MCPA, oxadiazon and propanil showed
resistance indices of one, indicating that all
herbicides tested had equal activity to both Rand
S-biotypes. It was concluded that these
herbicides could be effective for the control
of resistant A. plantago-aquatica biotypes in
rice paddy fields.
Descrição
Palavras-chave
alisma plantago-aquatica dose response bioassay growth stage sulfonylureas ensaios de dose-resposta estado fenológico sulfonilureas
Contexto Educativo
Citação
"Revista de Ciências Agrárias". ISSN 0871-018X. 31:1 (2008) 173-193
Editora
Sociedade de Ciências Agrárias de Portugal