Pesquisa | SciELO

Abstract Background The use of glyphosate on glyphosate-tolerant soybean crops led to improved control of a wide range of weeds, which resulted in reduced costs with the no-till system. The emergence of the first herbicide-resistant weeds have driven an increase in glyphosate applications, and even though those soybean materials have a low sensitivity to glyphosate, the rhizobial symbionts could be affected by the herbicide, and plants might be indirectly injured. Objective This study aimed to determine the effect of multiple glyphosate applications throughout the soybean crop cycle on plant growth, nodulation and biological nitrogen fixation (BNF). Methods The effects of one, two and three treatments of a recommended dose of glyphosate on BNF and growth of glyphosate-tolerant soybean plants were evaluated in greenhouse and field experiments. Results Two or more applications of glyphosate inhibited the BNF and growth of soybean plants. Under controlled conditions, at least one glyphosate application at V1 affected the number and mass of nodules per plant, and successive applications in advanced phonological stages resulted in the inhibition of nodule growth. With two and three sprayings of glyphosate, the proportion of N derived from the air in plants was reduced by 41% compared with the treatment without glyphosate. In field experiments, detrimental effects of three sequential applications of glyphosate on number of nodules per plant (-25%), biomass production (-21%) and grain yield (-36%) were detected. Conclusions Multiple glyphosate applications of glyphosate inhibited the BNF and growth of soybean plants and it could be as damaging as +weed interference. Nomenclature: Glyphosate; soybean, Glycine max (L.) Merril

Cód. do Índice	Elemento
ti	título do artigo
au	autor
kw	palavras-chave do artigo
subject	assunto (palavras do título, resumo e palavras-chave)
ab	resumo
ta	título abreviado da revista (ex. Cad. Saúde Pública)
journal_title	título completo da revista (ex. Cadernos de Saúde Pública)
la	código do idioma da publicação (ex. pt - Português, es - Espanhol)
type	tipo do documento
pid	identificador da publicação
publication_year	ano de publicação do artigo
sponsor	financiador
aff_country	código do país de afiliação do autor
aff_institution	instituição de afiliação do autor
volume	volume do artigo
issue	número do artigo
elocation	elocation
doi	número DOI
issn	ISSN da revista
in	código da coleção SciELO (ex. scl - Brasil, col - Colômbia)
use_license	código da licença de uso do artigo

Não foram encontrados documentos para sua pesquisa