Arg-128-Leu target-site mutation in PPO2 evolves in wild poinsettia (Euphorbia heterophylla) with cross-resistance to PPO-inhibiting herbicides
Autor: | Franck E. Dayan, Rubem S. Oliveira, Rafael Romero Mendes, Hudson Kagueyama Takano, Todd A. Gaines, Fernando Storniolo Adegas |
---|---|
Přispěvatelé: | STATE UNIVERSITY OF MARINGÁ, MARINGÁ, COLORADO STATE UNIVERSITY, FORT COLLINS, FERNANDO STORNIOLO ADEGAS, CNPSO, COLORADO STATE UNIVERSITY, FORT COLLINS. |
Rok vydání: | 2020 |
Předmět: |
education.field_of_study
biology Chemistry Population Plant Science Monooxygenase biology.organism_classification Euphorbia heterophylla Molecular biology Herbicide resistance chemistry.chemical_compound Resistência a Pesticida Erva Daninha Herbicida Protoporphyrinogen oxidase Weeds Weed education Agronomy and Crop Science Ambrosia artemisiifolia Cross-resistance Lactofen |
Zdroj: | Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA-Alice) Empresa Brasileira de Pesquisa Agropecuária (Embrapa) instacron:EMBRAPA |
ISSN: | 1550-2759 0043-1745 |
DOI: | 10.1017/wsc.2020.42 |
Popis: | Wild poinsettia (Euphorbia heterophylla L.) is a troublesome broadleaf weed in grain production areas in South America. Herbicide resistance to multiple sites of action has been documented in this species, including protoporphyrinogen oxidase (PPO) inhibitors. We investigated the physiological and molecular bases for PPO-inhibitor resistance in a E. heterophylla population (RPPO) from Southern Brazil. Whole-plant dose–response experiments revealed a cross-resistance profile to three different chemical groups of PPO inhibitors. Based on dose–response parameters, RPPO was resistant to lactofen (47.7-fold), saflufenacil (8.6-fold), and pyraflufen-ethyl (3.5-fold). Twenty-four hours after lactofen treatment (120 g ha−1) POST, RPPO accumulated 27 times less protoporphyrin than the susceptible population (SPPO). In addition, RPPO generated 5 and 4.5 times less hydrogen peroxide and superoxide than SPPO, respectively. The chloroplast PPO (PPO1) sequences were identical between the two populations, whereas 35 single-nucleotide polymorphisms were found for the mitochondrial PPO (PPO2). Based on protein homology modeling, the Arg-128-Leu (homologous to Arg-98-Leu in common ragweed [Ambrosia artemisiifolia L.] was the only one located near the catalytic site, also in a conserved region of PPO2. The cytochrome P450 monooxygenase inhibitor malathion did not reverse resistance to lactofen in RPPO, and both populations showed similar levels of PPO1 and PPO2 expression, suggesting that metabolic resistance and PPO overexpression are unlikely. This is the first report of an Arg-128-Leu mutation in PPO2 conferring cross-resistance to PPO inhibitors in E. heterophylla. |
Databáze: | OpenAIRE |
Externí odkaz: |