||Herbicidal Selectivity and Mode of Action of EK–2612 in Rice and Barnyardgrass
Oh, Taek–Keun ,
Uddin, Md. Romij ,
Lee, Jeung Ju ,
Shinogi, YoshiyukiPark, Kee Woong
284 , 2015-09-18 , Faculty of Agriculture, Kyushu University
EK–2612 [5–(2–3 dihydro–2,2,4,6,7–pentamethyl benzofuran–5–yl)–2–[1–(allyoxyimino) butyryl]–3 hydroxy cyclohex–2–en–1–one] is a new herbicide being developed for the selective post–emergence control of a wide range of grass weeds. It is a member of the class of cyclohexane–1,3–diones which inhibits chloroplastic acetyl–CoA carboxylase (ACCase, EC 188.8.131.52) and block fatty acid biosynthesis. A study was conducted to evaluate the herbicidal performances of EK–2612 especially on barnyardgrass and rice. The compound EK–2612 performed excellent post–emergence activity against barnyardgrass exhibiting the growth inhibition of barnyardgrass by 74 and 84% at 60 and 120 g a.i. ha^<–1>, respectively. With increasing EK–2612 concentration, acetyl–CoA carboxylase activity was more inhibited in barnyardgrass than in rice. Chlorophyll content in barnyardgrass was reduced greatly with the increase of EK–2612 concentrations, whereas chlorophyll content in rice was not affected by EK–2612. No phytotoxic symptoms were observed on rice due to EK–2612, having a good rice safety up to the level of 120 g a.i. ha^<–1>. These results suggest that EK–2612 has an excellent pre–emergence herbicidal activity against barnyardgrass without hampering the growth of rice.