PDF《河北省和山东省黄瓜霜霉病菌对氟吡菌胺的抗性》

386 植物保护学报46卷strains with low and moderate resistance accounted for 36.18% and 15.71%, respectively;

the resistance frequency to fluopicolide was 51.89%, and the average resistance index was 0.34 for all tested strains. The three indexes of P. cubensis tended to increase year by year and varied as the detected regions changed. The results of the trials of control efficacy of fungicides against the disease showed that spray of fluopicolide ・ propamocarb hydrochloride 687.5 g/L SC at the recommended rate gave significantly higher control against cucumber downy mildew in Hebei and Shandong than spray of mefenoxam・man- cozeb

68 WG, metalaxyl・mancozeb

58 WP, mancozeb

80 WP or azoxystrobin

250 g/L SC at the recom- mended rates, but the control efficacy of fluopicolide・propamocarb hydrochloride 687.5 g/L SC signifi- cantly decreased from 92.58%-93.31% in

2011 to 80.07%-80.82% in 2016. The monitoring results of wide occurrence of low resistance to fluopicolide was consistent with the field trial result of obviously less effectiveness of fluopicolide ・ propamocarb hydrochloride 687.5 g/L SC, indicating that the strate- gies of resistance management to fluopicolide in P. cubensis need to be established and implemented, such as limiting the spray times of fluopicolide ・ propamocarb hydrochloride 687.5 g/L SC to twice within a growth season of cucumber and using fluopicolide・ propamocarb hydrochloride 687.5 g/L SC in alternation with the other oomycete fungicides with different modes of action for control of cucumber downy mildew in Hebei and Shandong provinces. Key words: Pseudoperonospora cubensis;

fluopicolide;

resistance;

temporal and spatial dynamics;

con- trol efficacy 由古巴假霜霉菌Pseudoperonospora cubensis引 起的黄瓜霜霉病在很多国家均是黄瓜生产上的毁灭 性病害 (Lebeda &

Cohen, 2011) .作为一种气传病 害, 它流行性强, 传播速度快, 如遇阴雨天, 错过最佳 防治时机或用药不当, 可使黄瓜大幅减产甚至毁棚 拉秧 (马辉杰和王文桥, 2010) .生产中该病害主要 依靠化学防治 (Gisi &

Sierotzki, 2008;

Savory et al., 2011) , 防治药剂除了代森锰锌、 氢氧化铜、 百菌清、 氰霜唑、 苯酰菌胺等非内吸性杀菌剂外, 还有苯甲酰 胺类的氟吡菌胺, 苯基酰胺类的甲霜灵、 精甲霜灵、 f霜灵, QoI类的嘧菌酯、 吡唑醚菌酯、 啶氧菌酯、 f 唑菌酮, 氰基乙酰胺肟类的霜脲氰, 羧酸酰胺类的烯 酰吗啉、 双炔酰菌胺、 氟吗啉、 缬霉威、 苯噻菌胺, 氨 基甲酸酯类的霜霉威, 哌啶基噻唑异唑啉类的氟噻 唑吡乙酮及三唑嘧啶类的唑嘧菌胺等内吸性杀菌剂 及其混剂可用 (Urban &

Lebeda, 2006) .黄瓜霜霉 病菌被列为

12 种具有高度抗性风险的病原菌之一 (Fungicide Resistance Action Committee, 2014) .由 于不合理用药, 包括该病菌在内的许多植物卵菌已 对甲霜灵和嘧菌酯等内吸性杀菌剂产生抗性, 导致 相关药剂防效明显下降或防治失败 (Ishii et al., 2001;

Brent &

Hollomon, 2007;

孟润杰等, 2017) . 氟吡菌胺是一种防治植物卵菌病害高效的苯甲 酰胺类内吸剂, 抑制致病疫霉Phytophthora infestans 和辣椒疫霉Phytophthora capsici生活史中游动孢子 释放和游动、 休止孢萌发、 菌丝生长和孢子囊产生 (Jackson et al., 2010) , 具有良好的内吸传导性, 持效 期长.氟吡菌胺作用靶标是致病疫霉菌丝和游动孢 子中类血影蛋白, 可影响细胞的有丝分裂.氟吡菌 胺作用机理独特, 与苯基酰胺类、 甲氧基丙烯酸酯类 和羧酸酰胺类杀菌剂均无交互抗性 (Toquin et al., 2006) . 在国外, 氟吡菌胺分别与霜霉威盐酸盐、 三乙膦 酸铝和丙森锌制成混剂, 用于黄瓜霜霉病、 马铃薯晚 疫病、 辣椒疫病等卵菌病害的防治 ( Cooke &