摘要
【目的】明确青海省当归根腐病菌种类及筛选用于该病害防治的有效杀菌剂。【方法】首先采用单孢分离法分离病原菌,根据柯赫氏法则测定菌株致病性,并对病原菌进行形态学特征观察;然后扩增rDNA-ITS和TEF-1α基因序列,经测序、比对及联合构建系统发育树,对病原菌进行分子鉴定;最后利用菌丝生长速率法测定7种杀菌剂对病原菌的抑制效果。【结果】2020—2022年,从青海省民和县、湟中县和乐都县采集地上部萎蔫干枯、根部腐烂变褐的当归根腐病样本72份,采样地病害发生率为15%~45%。共分离得到87株真菌,经致病性测定,发现均为当归根腐病菌,它们分别为腐皮镰刀菌(Fusarium solani)、燕麦镰刀菌(F.avenaceum)、锐顶镰刀菌(F.acuminatum)、柔毛镰刀菌(F.flocciferum)、木贼镰刀菌(F.equiseti)和粉红螺旋聚孢霉(Clonostachys rosea)。其中,优势病原菌为腐皮镰刀菌、燕麦镰刀菌和锐顶镰刀菌,分离频率分别为33.4%、27.6%和26.4%。室内药剂试验表明硅唑·咪鲜胺对6种当归根腐病菌的抑制作用最好,EC_(50)为0.011~1.051 mg·L^(-1);50%苯醚甲环唑悬浮剂对锐顶镰刀菌、燕麦镰刀菌、柔毛镰刀菌和腐皮镰刀菌的抑制效果较好,EC_(50)值介于0.007与0.393 mg·L^(-1)之间,但是对粉红螺旋聚孢霉和木贼镰刀菌的抑制效果较差。石硫合剂对6种病原菌抑制效果最差,EC_(50)值介于1.853与4.701 mg·L^(-1)之间。【结论】本研究初步明确了青海省当归根腐病菌种类,并为生产上合理选用杀菌剂防治当归根腐病提供了科学依据。
[Objective]This study aimed to clarify the species of root rot pathogens from Angelica sinensis in Qinghai Province,and screened effective fungicide for management this disease.[Method]Firstly,single spore isolation method was used to isolate the pathogens,and the pathogenicity of isolates was determined based on Koch's rule.Secondly,morphological characteristics of the pathogens were observed,and the sequences of rDNA-ITS and TEF-1αgenes were amplified,sequenced,compared and combined to construct phylogenetic tree for molecular identification of pathogens.Finally,the inhibitory effects of seven fungicides on the hypha of pathogens were determined by mycelial growth rate method for screening of effective fungicide.[Result]From 2020 to 2022,72 A.sinensis root rot samples with wilted aboveground parts and brown rotted roots were collected from Minhe,Huangzhong,and Ledu counties in Qinghai Province,where disease incidence ranged from 15%to 45%.Totally,87 fungi isolates were isolated and all of them were pathogenic to the root of A.sinensis.The pathogens were Fusarium solani,F.avenaceum,F.acuminatum,F.flocciferum,F.equiseti and Clonostachys rosea according to identification results,and the dominant pathogens were F.solani,F.avenaceum and F.acuminatum with the isolation frequency of 33.4%,27.6%and 26.4%,respectively.Laboratory fungicide experiments demonstrated that flusilazole·prochloraz exhibited the strongest inhibition against the six pathogens,with EC_(50)value ranging from 0.011 to 1.051 mg·L^(-1).Difenoconazole 50%SC demonstrated good efficacy against F.acuminatum,F.avenaceum,F.flocciferum,and F.solani(EC_(50)of 0.007-0.393 mg·L^(-1))but with poor inhibition rates against C.rosea and F.equiseti.Lime sulfur had the weakest inhibitory effect on all six pathogens,with EC_(50)values between 1.853 and 4.701 mg·L^(-1).[Conclusion]This study preliminarily identifies species of root rot pathogens from A.sinensis in Qinghai Province,and provides a scientific basis for rational selecting fungicides to control root rot of A.sinensis in production.
作者
祁鹤兴
李沐阳
段晓明
QI Hexing;LI Muyang;DUAN Xiaoming(College of Agriculture and Animal Husbandry,Qinghai University,Xining 810016,China)
出处
《安徽农业大学学报》
2025年第6期985-993,共9页
Journal of Anhui Agricultural University
基金
浙江省重点研发计划项目(2023C04023)。
关键词
当归
根腐病
镰刀菌
病原多样性
药剂筛选
Angelica sinensis
root rot
Fusarium spp.
diversity of pathogenic fungi
screening of fungicide
