Luiz Fernando D Martini1, Nilda R Burgos2, José Alberto Noldin3, Luis Antonio de Avila1, Reiofeli A Salas2. 1. Departamento de Fitossanidade, Universidade Federal de Pelotas (UFPel), Capão do Leão, Pelotas, RS, Brazil. 2. Department of Crop, Soil and Environmental Sciences, University of Arkansas, Fayetteville, AR, USA. 3. Empresa de Pesquisa Agropecuária e Extensão Rural de Santa Catarina-Epagri/Estação Experimental de Itajaí, Itajaí, SC, Brazil.
Abstract
BACKGROUND: Rice production is highly affected by weed competition. The efficacy of chemical weed control and crop safety is a function of absorption, translocation and metabolism of herbicides. This study investigates the effect of cold stress 22/16 °C (day/night) on absorption, translocation and metabolism of (14)C-bispyribac-sodium on rice seedlings. RESULTS: Maximum (14)C-bispyribac-sodium absorption occurred at 24 h after herbicide treatment and was stimulated by the warm 30/22 °C (day/night) temperature. A large amount of total absorbed herbicide was retained in the treated leaf, indicating that bispyribac-sodium had minimal translocation to other plant parts. Piperonyl-butoxide (a P450 inhibitor) plus herbicide caused greater injury than the herbicide alone. In addition, injury on rice plants was enhanced by exposure to cold, emphasizing the negative effect on herbicide metabolism. In the thin-layer chromatography metabolism experiment, cold-grown plants had higher injury and retained more of the parent herbicide than plants grown at a warm temperature. CONCLUSION: Cold stress reduces bispyribac-sodium absorption and metabolism in rice, but has no effect on translocation.
BACKGROUND:Rice production is highly affected by weed competition. The efficacy of chemical weed control and crop safety is a function of absorption, translocation and metabolism of herbicides. This study investigates the effect of cold stress 22/16 °C (day/night) on absorption, translocation and metabolism of (14)C-bispyribac-sodium on rice seedlings. RESULTS: Maximum (14)C-bispyribac-sodium absorption occurred at 24 h after herbicide treatment and was stimulated by the warm 30/22 °C (day/night) temperature. A large amount of total absorbed herbicide was retained in the treated leaf, indicating that bispyribac-sodium had minimal translocation to other plant parts. Piperonyl-butoxide (a P450 inhibitor) plus herbicide caused greater injury than the herbicide alone. In addition, injury on rice plants was enhanced by exposure to cold, emphasizing the negative effect on herbicide metabolism. In the thin-layer chromatography metabolism experiment, cold-grown plants had higher injury and retained more of the parent herbicide than plants grown at a warm temperature. CONCLUSION: Cold stress reduces bispyribac-sodium absorption and metabolism in rice, but has no effect on translocation.
Authors: Valerio Converso; Sarah Fearn; Ecaterina Ware; David S McPhail; Anthony J Flemming; Jacob G Bundy Journal: Sci Rep Date: 2017-09-06 Impact factor: 4.379