核盘菌对菌核净的抗药性机制初探

经药剂筛选获得对菌核净不同表型的核盘菌(Sclerotinia sclerotiorum ) 抗药性突变体。与敏感亲本菌株相比, 抗药突变体MN 61 (MR ) 和MN 91 (HR) 在含1% 和8% 葡萄糖的PDA 上生长受到抑制,MN 113 (LR) 只对1% 葡萄糖敏感。通过测定抗药突变体MN 61 和野生敏感菌株PN 061 的电导率, 发现抗药突变体能在更短的时间里渗出更多的电解质。抗药突变体苯丙氨酸解氨酶活性比敏感亲本菌株高出1 倍以上, 当用不同浓度菌核净处理或饥饿处理时, 抗药突变体和敏感亲本菌株PAL 活性均上升, 但抗药突变体的酶活始终高于敏感亲本菌株。

Study on Resistance Mechanism of Sclerotinia sclerotiorum to Dimethachlon

The mutants in different resistence level of Sclerotinia sclerotiorum to dimethachlon were selected on PDA medium amended with the fungicide from 0.5 μg·ml -1 to 50.0 μg·ml -1 . The growth of mutants MN61(MR)and MN91(HR) was inhibited on the PDA containing 1% and 8% dextrose, and MN113(LR) was only sensitive to 1% dextrose compared with their parents incubated on the 2% dextrose medium. Dimethachlon caused more electrolyte leakage of the mutant cells than that of its parent isolate. The activity of PAL( L-phenylalanine ammonia lyase) of mutant MN61 was higher than that of sensitive isolate PN061 when they were incubated in the solution of nutrient deficieny or treated with 5 μg·ml -1 or 20 μg·ml -1 dimethachlon.