河南农业科学2026，Vol.55Issue(3)：97-106,10.DOI:10.15933/j.cnki.1004-3268.2026.03.010
大豆拟茎点种腐病菌分离鉴定、生物学特性分析及防控药剂筛选
Isolation,Identification,Biological Characterization of Diaporthe longicolla and Screening of Antifungal Drugs
摘要
Abstract
To clarify the pathogenic characteristics and potential for chemical control of soybean Phomopsis seed decay in Zhoukou City,Henan Province,typical diseased soybean stems were collected for pathogen isolation and identification.The effects of temperature and humidity on mycelial growth and spore germination were determined,and the in vitro fungicidal activity of ten fungicides against the isolate was assessed using the mycelial growth inhibition method,and seed-coating trials were conducted to evaluate the protective efficacy of each treatment in terms of seed germination and suppression of pathogen infection.The results showed that one fungal strain,designated ZK-2024,was obtained.Based on morphological characteristics and phylogenetic analysis of multi-locus DNA sequences(rDNA ITS and TEF1-α),the isolate was conclusively identified as Diaporthe longicolla,the causal agent of soybean Phomopsis seed decay.The optimal temperature for mycelial growth was 30℃,while the optimum for conidial germination was 25℃.High humidity significantly promoted both mycelial growth and conidial germination,with a statistically significant interaction between temperature and humidity.Fungicide screening revealed that 90%carbendazim water-dispersible granules and 430 g/L tebuconazole suspension concentrate exhibited the strongest inhibitory activity against the isolate ZK-2024,with median effective concentrations(EC50)of 0.366 0 mg/L and 0.444 4 mg/L,respectively.In seed-coating trials,seeds treated with pyraclostrobin plus infested soil achieved a germination rate of 93.33%and showed no mycelial coverage,significantly outperforming all other fungicide treatments.This performance was statistically comparable to the untreated control(non-coated seeds+sterile soil).In summary,this study reported the first successful field isolation and molecular identification of Diaporthe longicolla in Zhoukou.It elucidated key biological traits of the pathogen and identifies carbendazim and tebuconazole as highly effective fungicides for in vitro suppression.Moreover,pyraclostrobin demonstrated excellent protective efficacy in seed-coating assays under controlled conditions,highlighting its potential as a candidate seed treatment agent for managing Phomopsis seed decay in soybean.关键词
大豆拟茎点种腐病菌/生物学特性/毒力测定/抑菌药物筛选/多菌灵/吡唑醚菌酯Key words
Diaporthe longicolla/Biological characteristics/Toxicity test/Screening of antifungal drugs/Carbendazim/Pyraclostrobin分类
农业科技引用本文复制引用
尹坤,黄玉波,梁路,庄秋丽,田开月,徐博涵,张卫杰,张东辉..大豆拟茎点种腐病菌分离鉴定、生物学特性分析及防控药剂筛选[J].河南农业科学,2026,55(3):97-106,10.基金项目
河南省科技研发联合基金重大项目(235101610015) （235101610015）
河南省科技研发计划联合基金项目(235101610071) （235101610071）
