Data/hora: 09/06/2024 07:42:04

Provedor de dados: | 87
País: | Brazil
Título: | Enzymatic Properties and Ryegrass Resistance Mechanism to Iodosulfuron-Methyl-Sodium Herbicide
Autores: | MARIANI,F.; SENSEMAM,S.A.; VARGAS,L.; AGOSTINETO,D.; ÁVILA,L.A.; SANTOS,F.M.
Data: | 2019-01-01
Ano: | 2019
Palavras-chave: | Acetolactate synthase (ALS); Lolium multiflorum; Amino acids; Sulfonylurea.
Resumo: | ABSTRACT: Ryegrass(Lolium multiflorum)is one of the most worrisome species with regard to herbicide resistance. This study aimed at characterizing the acetolactate synthase (ALS) enzyme activity of resistant biotypes (NC and AR) and susceptible biotypes to iodosulfuron-methyl-sodium (iodosulfuron). Different concentrations of pyruvate (1, 10, 20, 40, 60, 80 and 100 mM), of iodosulfuron (0 to 100 µM for the resistant biotypes and 0 to 0.5 µM for the susceptible biotype) and concentrations of valine, leucine and isoleucine (0, 0.001, 0.01, 0.1, 1, 10 and 100 mM) were used for the in vitro characterization. According to the results, the Michaelis constant (Km) values (pyruvate) for the assessed biotypes were similar. With iodosulfuron, resistant biotypes needed 395 to 779 times more herbicide in order to inhibit 50% of the enzyme activity, compared to the susceptible biotype. This confirmed a sensitivity modification of the ALS enzyme in the resistant biotypes. The resistant biotypes were less sensitive to the inhibition of the enzyme activity in the presence of the three amino acids. It was possible to conclude that biotype resistance was due to the enzyme insensitivity to iodosulfuron.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100201
Editor: | Sociedade Brasileira da Ciência das Plantas Daninhas
Relação: | 10.1590/s0100-83582019370100001
Formato: | text/html
Fonte: | Planta Daninha  v.37 2019
Fonte: | info:eu-repo/semantics/openAccess