| 摘要: |
| 【目的】明确宁夏银川地区苜蓿根腐病的病原菌种类及其优势致病菌，为该地区苜蓿根腐病的有效防控提供理论依据。【方法】2023年从宁夏银川地区采集不同品种苜蓿根腐病病样107 株，采用组织分离法对病样在PDA和V8培养基上进行分离纯化，根据菌落形态特征和孢子形态特征筛选具有代表性的菌株，利用真菌rDNA-ITS序列引物对14株代表菌株基因组DNA进行PCR扩增，再采用β-tubulin基因组引物对分离的6 株镰刀菌进行PCR扩增；以甘农3号苜蓿品种为材料，利用水培法对14 株代表菌株进行致病性测定。【结果】从107株罹病苜蓿样品中共分离获得213株分离物，根据形态学特征以及分子生物学技术最终确定宁夏银川地区苜蓿根腐病病原菌共有14 种，分别为镰刀菌属的腐皮镰刀菌（Fusarium solani）、木贼镰刀菌（F.equiseti）、新孢镰刀菌（F.neocosmosporiellum）、锐顶镰刀菌(F.acuminatum)、黄色镰刀菌（F.culmorum）和尖孢镰刀菌（F.oxysporum），腐霉属的瓜果腐霉（Pythium aphanidermatum），土赤壳属的Dactylonectria macrodidyma，丝孢属的立枯丝核菌（Rhizoctonia solani），弯孢霉属的Curvularia moringae，链格孢属的Alternaria sp.，异茎点霉属的异茎点霉（Paraphoma radicina），粘帚霉属的粉红粘帚菌（Clonostachys rosea），织球壳属的织球壳枯萎菌（Plectosphaerella cucumerina），其中新孢镰刀菌(F.neocosmosporiellum)和D.macrodidyma首次在苜蓿上分离得到，优势病原菌为腐皮镰刀菌。致病性测定结果表明，14株不同病原菌均对甘农3号苜蓿品种有致病性，但不同病原菌间致病力存在显著差异，其中黄色镰刀菌的致病力最强，病情指数为91.11；其次为立枯丝核菌，病情指数为90.67，二者的病情指数均显著高于其他菌株，但二者之间无显著差异。【结论】宁夏银川地区苜蓿根腐病的病原种类有14种，其中镰刀菌属为优势属，腐皮镰刀菌为优势致病菌。14 种病原菌均对甘农3号苜蓿品种有致病性，但不同病原菌的致病力存在显著差异，其中以黄色镰刀菌和立枯丝核菌致病力较强。 |
| 关键词: 苜蓿根腐病 病原鉴定 致病性 宁夏银川 |
| DOI：DOI:10.13207/j.cnki.jnwafu.2025.06.010 |
| 分类号: |
| 基金项目:国家自然科学基金项目“枸杞内生嗜线虫镰刀菌效应蛋白FnEG1激发寄主防御反应的分子机理”（32260697） |
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| Identification and pathogenicity test of pathogens causing alfalfa root rot in Yinchuan,Ningxia |
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HE Xue, ZHANG Qiangqiang, GU Peiwei
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School of Agricultural,Ningxia University,Yinchuan,Ningxia 750021,China
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| Abstract: |
| 【Objective】This research aimed to identify the pathogen species and dominant pathogens of alfalfa root rot in Yinchuan,Ningxia,to provide theoretical basis for effective control of alfalfa root rot in this region.【Method】A total of 107 samples of alfalfa root rot were collected from Yinchuan,Ningxia,China in 2023.According to the morphological characteristics of colony and spore,the representative strains were selected.The genomic DNA of 14 representative strains were amplified by polymerase chain reaction (PCR) with the primers of fungal rDNA-ITS sequence, and 6 isolates of Fusarium were amplified by PCR with β-tubulin primers.The pathogenicity of 14 representative strains was tested by hydroponic method.【Result】A total of 213 isolates were obtained from 107 diseased samples.Based on their morphological characteristics and molecular biological techniques,14 pathogens of alfalfa root rot were identified in Yinchuan,Ningxia,which were Fusarium solani,F.equiseti,F.neocosmosporiellum,F.acuminatum，F.culmorum，F.oxysporum,Pythium aphanidermatum,Dactylonectria macrodidyma,Rhizoctonia solani,Curvularia moringae,Alternaria sp.,Paraphoma radicina,Clonostachys rosea,and Plectosphaerella cucumerina.Among the 14 pathogens,F.neocosmosporiellum and D.macrodidyma were isolated from alfalfa for the first time,and the dominant pathogen was F.solani.The results of pathogenicity test indicated that all the 14 isolates showed pathogenicity to alfalfa variety Gannong 3,but significant differences were observed in the pathogenicity of the isolates.F.culmorum showed the highest pathogenicity,with a disease index of 91.11,followed by R.solani with a disease index of 90.67.The disease index of F.culmorum and R.solani were significantly higher than that of other isolates, but there was no significant difference between F.culmorum and R.solani.【Conclusion】There were 14 pathogen species of alfalfa root rot in Yinchuan,Ningxia,China.All the 14 pathogens showed pathogenicity to alfalfa,but the pathogenicity of different pathogens was significantly different,among which F.culmorum and R.solani showed the higher pathogenicity. |
| Key words: alfalfa root rot pathogen identification pathogenicity Yinchuan,Ningxia |
