海南甜瓜炭腐病病原菌鉴定及防治药剂筛选  

Pathogen identification and fungicide screening of melon charcoal rot disease

作　　者：吴会杰[1] 康保珊[1] 杨士兵 郭珍 严蕾艳 王丽[1] 江梦格 彭斌[1] 刘莉铭[1] 古勤生[1] WU Huijie;KANG Baoshan;YANG Shibing;GUO Zhen;YAN Leiyan;WANG Li;JIANG Meng-ge;PENG Bin;LIU Liming;GU Qinsheng(Zhengzhou Fruit Research Institute,Chinese Academy of Agricultural Sciences,Zhengzhou,450009,Henan,China;Institute of Vegetables,Ningbo Academy of Agricultural Sciences,Ningbo 315040,Zhengjiang,China)

机构地区：[1]中国农业科学院郑州果树研究所,郑州450009 [2]宁波市农业科学院蔬菜研究所,浙江宁波315040

出　　处：《果树学报》2022年第3期456-463,共8页Journal of Fruit Science

基　　金：宁波市公益类科技计划项目(202002N3003);中央级公益性科研院所基本科研业务费专项(1610192021401)。

摘　　要：【目的】明确海南大棚甜瓜急性萎蔫的病因及筛选防控该病害的适宜化学药剂。【方法】通过室内组织分离、鉴定及致病性测定明确了造成海南甜瓜萎蔫的主要病原菌。采用生长速率法测定了8种杀菌剂对该病原菌的室内毒力。【结果】致病性分析表明,甜瓜茎及茎基部接种病原菌72 h后表现出明显的坏死,从表现症状的部位重新分离到该病原菌。形态学观察发现其初生菌丝白色,随后变灰褐色,最后形成大量的黑色微菌核,在PDA上不产生有性繁殖结构。基于真菌内部转录间隔区(internal transcribed spacer,ITS)和特异序列进化树分析,发现海南甜瓜病菌分离物HN-melon与菜豆壳球孢(Macrophomina phaseolina,M.phaseolina)聚为一个分支。结合形态学、致病性及发病特征判定引起海南大棚甜瓜急性萎蔫、死亡的病原菌为M.phaseolina。杀菌剂对菜豆壳球孢的毒力测定表明,8种杀菌剂对菜豆壳球孢的毒力差异很大,抑制作用较好的是50%咪鲜胺锰盐,毒力最强,抑制中浓度EC50为0.6849 mg·L^(-1);其次为250 g·L^(-1)吡唑醚菌酯,EC_(50)为1.6124 mg·L^(-1)。【结论】首次鉴定了海南甜瓜发生急性萎蔫的病原菌是M.phaseolina。室内毒力结果表明,50%咪鲜胺锰盐和250 g·L^(-1)吡唑醚菌酯有明显的抑制作用。【Objective】Cucumis melo is one of the important economic crops of Cucurbitaceae in China. In recent years, melon root diseases are becoming more and more serious because of promotion of protected melon cultivation mode and continuous cropping. In 2018, 20 hectares of Jinxiangyu melons were planted in Ledong, Sanya, Hainan province, but the whole plants wilted suddenly and died about20 days before the maturity period. The disease mortality rate was about 90%, the melon production losses were serious and the quality lost commodity, which caused heavy losses. The melon roots and stem bases showed brown rot and a large number of small black particles were gathered. In the study,we analyzed and clarified the cause of sudden wilt and death of melon in greenhouse and screened suitable chemical agents, and the aim was to screen out fungicides suitable for the prevention and treatment of melon charcoal rot and lay the foundation for effective prevention and control of the disease.【Methods】Melon decaying roots were collected for isolation of the pathogen by using the traditional tissue separation method. A small piece of tissue about 4 mm × 4 mm was cut from the junction of diseased and healthy roots, sterilized and dried, and then cultured and purified on PDA, before the purified pathogens were stored on PDA at 4 ℃. To confirm the pathogenicity, the stems and basal stem of the melon variety Jinxiangyu and pumpkin rootstocks ZGNG-12 were inoculated by stem cake inoculation method, and the pathogen was re-isolated from the inoculated sites. The pathogen was identified through morphological observation and molecular biology methods, and the indoor toxicity of 8 kinds of fungicides on the mycelium of the melon charcoal rot was determined by the growth rate method.【Results】Several isolates were obtained by tissue isolation and purification. Morphological observation revealed that the hyphae of the pathogen grew rapidly, growing radially around the surface of the medium. The colony diameter could reach 80 mm at 2

关 键 词：甜瓜 甜瓜炭腐病病原菌 致病力鉴定 室内毒力 

分 类 号：S652[农业科学—果树学]