Inductive Resistance to Chlorsulfuron in Beckmannia syzigachne and Alopecurus japonicum in Vitro

LI Yiwei, 2CHEN Yifeng, 1LI Yongfeng, 2TANG Risheng, and 2MEI Chuansheng ( 1Institute of Agricultural Modernization, Jiangsu Academy of Agricultural Sciences, Nanjing 210014; 2Institute of Agrobio

Beckmannia syzigachne ; Alopecurus japonicum ; chlorsulfuron; resistance; callus subculture

Characteristics of resistance response to chlorsulfuron was observed in young panicle calli of both weeds via subculture. During subculture sensitivity of acetolactate synthase (ALS) in both calli greatly decreased along with increase of chlorsulfuron concentration. IC 50 value (concentration causing 50% inhibition) of ALS activity increased from 1 0 μg/L to 300 μg/L after 6-12 subcultures in Beckmannia syzigachne , or from 1 0 μg/L to over 100 μg/L after 4-10 subcultures in Alopecurus japonicum , indicating that obvious development of the herbicide resistance has appeared in both calli. Moreover, this inductive resistance also in regenerated plantlets of Beckmannia syzigachne . Inhibition of resistant plantlet growth at 200 μg/L of chlorsulfuron lowered, and lethal rate of these plantlets at 1 000 μg/L of chlorsulfuron became smaller. Neither growth of both callus nor calli differentiation potential and plantlet development of Beckmannia syzigachne was influenced by chlorsulfuron during subculture.