Investigation of Herbicide Safeners and its Mode of Safening Action Ⅰ. Effect of N-(4-chlorophenyl)maleimide on Metolachlor Absorption and Metabolism

제초제(除草劑) 약해경감물질(藥害輕減物質) 탐색(探索)과 작용기구(作用機構) 규명(糾明) Ⅰ. Metolachlor 흡수(吸收) 및 대사(代謝)에 대한 N-(4-chlorophenyl)maleimide의 효과(效果)

  • Chun, Jae-Chul (College of Agriculture, Jeonbuk National University) ;
  • Ma, Sang-Yong (College of Agriculture, Jeonbuk National University)
  • Published : 1994.12.30

Abstract

Mode of safening action of N-(4-chlorophenyl)maleimide (CPMI) on metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-l-methylethyl) acetamide] was investigated in sorghum(Sorghum bicolor L.). CPMI was synthesized by dehydration of N-(4-chlorophenyl)maleamic acid (CPMA) which was obtained from amination with maleic anhydride and 4-chloroaniline. Melting points of CPMA and CPMI (>95% purity) were $200-202^{\circ}C$ and $116-118^{\circ}C$, respectively. Growth response study indicated that seed treatment of CPMI increased tolerance of sorghum shoot to metolachlor approximately threefold. Sorghum shoot was more sensitive to injury caused by metolachlor and CPMI activity than the root. Metolachlor was initially absorbed by sorghum shoot and metabolized to the metolachlor-glutathione conjugate in CPMI-untreated and treated shoots. However, CPMI treatment significantly accelerated metabolism of $[^{14}C]$metolachlor in sorghum shoot, resulting in decrease in metolachlor content and increase in formation of the glutathione conjugate. It was concluded that the protection against metolachlor injury conferred by CPMI appeared to be correlated to detoxification of metolachlor in sorghum shoot tissue.