罗汉松叶枯病菌(病原：罗汉松拟盘多毛孢）的生物学特性及其抑制药剂筛选

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中图分类号：S763 文献标志码：A 文章编号：1000-2006（2025）06-0255-06

Abstract：【Objective】Inorder toeffctivelypreventandcontrol thedisease，thisstudyaimstosystematically investigatethebiologicalcharacteristicsofthepathogen causing Podocarpus macrophylusleafblight diseaseandscreens effctive fungicides.【Method】The germinationrateof spores was measuredunderdiferent nutritional conditions， temperatures，pHlevels，and light treatmentsusing theglassslidegerminationmethodto studythe biological characteristicsofPestalotiopsispodocarpi.Thefourfungicides，including 75% （mass fraction）chlorothalonil， 50% （mass fraction）carbendazol， 80% （mass fraction）mancozeb，and 70% （mass fraction）thiophanate-methyl，were evaluatedinvitro fortheir eficacy inrestraining hyphal growthandconidiagermination.Thetoxicityregression equations were fitted to calculate the EC50 ，and effective fungicides were screened.【 Result】The host plant decoction could promote spore germination，with the optimal concentration being 10% .The spores could germinate between 15-35°C ，with the optimal temperature at 25‰ . The germination rate could exceed 50% at pH6-9 ，peaking at pH 7.The spores were insensitive tolight，withalternatinglight-darktreatmentresultinginslightlyhighergerminationratesthanother treatments.The most effective one against hyphal growth is carbendazol with the EC50 of 0.0489mg/L ，followed by thiophanate-methyl with the EC50 of 0.8505mg/L .Mancozeb and chlorothalonil are less effective against hyphal growth. Mancozeb demonstrates the strongest inhibitory effect on conidia germination with the EC 50 of 0.2573mg/L ，followed in decreasing orderofefectivenessbythiophanate-methyl，chlorothalonil，carbendazol.【Conclusion】Theoptimal concentration of P .macrophyllus decoction for spore germination of P .podocarpi is 10% . The optimal growth temperature and pH are 25‰ and 7，respectively.Carbendazol and mancozeb can be used as potential fungicides for controling podocarpus （ P .macrophylus）leaf blight disease，while their field control efficacy requires further research.

KeyWords：Podocarpusmacrophylusleafblight disease；Pestalotiopsispodocarpi；biological characteristics； fungicides screening

罗汉松（Podocarpusmacrophyllus）为常绿针叶乔木，适应性较强，适于生长在偏酸性的砂质土壤中，具有较高的观赏价值和药用价值[1-2]；其干材还是制作文具、家具等用品的优良材料[3]。（剩余12440字）