海南芒果蒂腐病对8种杀菌剂的抗药性测定

Resistance of Mango Stem-end Rot to Eight Fungicides in Hainan

[目的]明确海南芒果蒂腐病（Botryodiplodia theobromae）对8种杀菌剂的抗药性。[方法]以10 mg/L为鉴别剂量进行抗药性初步检测,采用菌丝生长抑制法测定EC50值。[结果]2个苯并咪唑类杀菌剂抗性频率分别为87.5%和90.1%;甾醇脱甲基抑制剂抗性频率在17.1%～74.9%之间。供试菌株对50%多菌灵WP的EC50值在3.23～33 113.11 mg/L之间;对70%甲基硫菌灵WP的EC50值在1.76～11 091.75 mg/L之间,50%多菌灵WP与70%甲基硫菌灵WP之间存在交互抗性。[结论]海南芒果可可球二胞对苯并咪唑类杀菌剂普遍存在抗药性。

[Aims] The study aims to clarify the resistance of Botryodiplodia the obromae to 8 fungicides. [Methods] The62 strains of B. theobromae were collected from mango orchard in Hainan to detected the resistance to 8 fungicides with10 mg/L as the distinctive concentration. The EC50 values were identified by the method of hypha growth inhibition of B. theobromae. [Results] The strains showed different level of resistance to all the eight fungicides, with a high frequency of 87.5 and 90.1% to benzimidazole fungicides, and the frequency of strobilurin fungicides ranged from17.1-74.9%. The EC50 values of 10 carbendazim-resistant strains ranged from 3.23-33 113.11 mg/L, the EC50 values of10 thiophanate-methyl-resistant strains ranged from 1.76-11 091.75 mg/L. The linear regression showed that there was cross-resistance between carbendazim 50% WP and thiophanate-methyl 70% WP, but there was no cross-resistance between difenoconazole 10% WG and prochlora 50% WP with low level of resistance. [Conclusions] The fungicide resistance of B. theobromae to benzimidazole was commonly present in Hainan.