节瓜炭疽病菌对嘧菌酯的敏感性及其交互抗性

Sensitivity of Colletotrichum orbiculareIsolated from Zucchini to Azoxystrobin and Cross-Resistance between Azoxystrobin and Other fungicides

为了对海南瓜类蔬菜炭疽病菌的抗性监测研究及抗性治理提供理论依据,对海南不同市县采集的节瓜炭疽病病样中分离纯化的90株炭疽病原菌进行了检测,采用菌丝生长速率法测定2种病原菌对嘧菌酯的敏感性。结果表明：经分生孢子形态鉴定节瓜炭疽病有胶孢炭疽菌（Colletotrichum gloeosporioides）和尖孢炭疽菌（C.acutatum）,胶孢炭疽菌为优势种群,占84.4%;2种病原菌对嘧菌酯的EC50在0.334 4-36.467 0μg/mL,平均为12.954 4μg/mL,敏感性分布接近于正态分布,EC50值之间表现较连续,故以平均EC50值为敏感性基线,用于节瓜炭疽病菌对嘧菌酯的田间抗药性监测。嘧菌酯与多菌灵、福美双、丙环唑和咪鲜胺不存在交互抗性。

The sensitivity of 90 C.orbiculare strains isolated and purified from zucchini samples infected with C.gloeosporioides and C.acutatumcollected from different cities（counties）in Hainan to Azoxystrobin by mycelial growth rate to provide the theoretical basis for resistance monitoring and management of melon vegetables against C.orbicularein Hainan.Results：There are C.gloeosporioides and C.acutatum in anthracnose of zucchini according to identification of conidium morphology.C.gloeosporioides is a dominant species and accounts for 84.4%.EC50 of C.gloeosporioides and C.acutatum is 0.334 4-36.467 0μg/mL and their average EC50 is 12.954 4μg/mL.The average EC50 value is used as the sensitivity baseline because the sensitivity distribution is close to Gaussian distribution,which can be used to monitor resistance of C.orbiculare to Azoxystrobin in zucchini field.There is no cross-resistance between Azoxystrobin and Carbendazim,Thiram,Propiconazoie,Prochioraz respectively.