Data/hora: 10/06/2024 13:31:44

Provedor de dados: 	Planta Daninha	
País: 	Brazil	
Título: 	Occurrence of Horseweed Biotypes with Low Susceptibility to Glyphosate in the States of Rio Grande do Sul, Paraná and Mato Grosso do Sul, Brazil	
Autores: 	RIZZARDI,M.A.; SCHNEIDER,T.; BIANCHI,M.A.; ROCKENBACH,A.P.	
Data: 	2019-01-01	
Ano: 	2019	
Palavras-chave: 	Conyza bonariensis; Conyza sumatrensis; Conyza canadensis; Resistance; Chemical control.	
Resumo: 	ABSTRACT: Horseweed is an annual cycle weed naturally controlled by the herbicide glyphosate. However, the continued use of this product has selected tolerant and resistant populations. The objective of this study is to analyze the occurrence of horseweed biotypes with a low glyphosate susceptibility in the states of Rio Grande do Sul, Paraná and Mato Grosso do Sul. Seeds of horseweed plants (Conyzaspp.) that survived glyphosate applications were collected in RR soybean crops, totaling 137 samples from 37 municipalities. The seeds of the biotypes were sown, and the plants originated from them, when they reached the stage of four to six leaves, were subjected to a treatment with 1,440ga.e.ha-1 of glyphosate. According to the results, 108biotypes were not controlled and 29 were controlled by the application of glyphosate. Thus, 78% of horseweed biotypes evaluated are not controlled by the dose 1,440ga.e.ha-1 of glyphosate, and 22% are susceptible to the same dose. Evaluating the distribution per state, Paraná, Rio Grande do Sul and Mato Grosso do Sul presented 83%, 77% and 77%, respectively, of biotypes not controlled by glyphosate at the dose used. Thus, most of the collected horseweed biotypes present a low sensitivity to glyphosate, thus confirming the high horseweed distribution with a low susceptibility to glyphosate in Mato Grosso do Sul, Paraná and Rio Grande do Sul.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100290	
Editor: 	Sociedade Brasileira da Ciência das Plantas Daninhas	
Relação: 	10.1590/s0100-83582019370100093	
Formato: 	text/html	
Fonte: 	Planta Daninha  v.37 2019	
Fonte: 	info:eu-repo/semantics/openAccess