采用土培法和田间小区试验法测定了芸苔素内酯(BR)对玉米的保护作用,并对其作用机理进行了初步研究。结果表明:BR的浸种浓度在0.01~0.04mg·L^-1范围内,能不同程度地缓解16.0μg·kg^-1胺苯磺隆对玉米的药害,BR浓度为0.02mg·L^-1时,解毒效果最好。用0.02mg·L^-1的BR浸种,能不同程度地缓解2.0~32.0μg·kg^-1的胺苯磺隆对玉米生长的抑制,但当胺苯磺隆浓度增加到64.0μg·kg^-1时,BR浸种无解毒作用;按15g ai/hm^2的剂量施用胺苯磺隆对玉米的减产率达11.8%,用BR0.02、0.04mg·L^-1浸种处理则减产率分别为0.2%和0.1%;BR提高胺苯磺隆处理的玉米幼苗中ALS活性可能是其保护玉米免受胺苯磺隆伤害的机理之一。
The results of effect and mechanism of BR for protecting maize from the phytotoxicity of ethametsulfuron showed that 0.01 - 0.04mg · L^-1 of BR protected the maize from the phytotoxicity of ethametsulfuron of 16.0μg · kg^-1 ; seed soaked with 0.02 mg · L^-1 BR could protect maize from the phytotoxicity of ethametsulfuron of 2.0 -32.0μg · kg^-1 under different degrees. BR had no effect when the concentration of ethametsulfuron was increased to 64.0μg · kg^-1. The result of field experiment showed that the output reduction ratio of maize was 11.8 % and seed soaked with 0.02 and 0.04 mg · L^-1BR, if 15g ai/hm^2 of ethametsulfuron was used, the output reduction ratio of maize was 0.2% and 0.1% respectively. BR was a potential safener. Seed soaked with BR could increase the content of branch amino acid obviously when corn seed was treated with ethametsulfuron. Accordingly the mechanism of BR for protecting maize from the phytotoxicity of ethametsulfuron could be interrelated with its stimulation on the activity of ALS.