商胜华 江艳 桑维钧 张开虹 杨茂发

摘 要：为明确烟草茎点病菌广生茎点霉Phoma omnivirens的最佳培养条件并筛选出有效的防治药剂，为生产实践中防治烟草茎点病提供理论依据。以病原菌P.omnivirens为试材，采用菌丝生长速率法，研究了病原菌P.omnivirens的生物学特性，并测定了12种供试杀菌剂对病原菌的抑制效果。病原菌P.omnivirens的最适培养基为牛肉膏蛋白胨培养基、燕麦培养基和马铃薯培养基;菌丝在5～30 ℃范围内均可生长，最适温度为30 ℃，5 ℃时菌丝生长最慢;PDA培养基pH为10时菌丝生长最快;光照对菌丝生长无显著影响;最佳碳源为蔗糖，最佳氮源为硝酸钾和硝酸钙;菌丝的致死温度为58 ℃ 10 min。12种杀菌剂中，3%中生菌素WP具有最佳抑菌效果，EC50最小，为0.9419 mg/L;其次是EC50为2.6940 mg/L的0.3%梧宁霉素AS和EC50为2.7917 mg/L的80%代森锰锌WP。生产上可将这3种药剂作为防治烟草茎点病的备选药剂。

关键词：烟草茎点病;广生茎点霉;生物学特性;毒力测定

中图分类号：S432.1

文献标识码：A

文章编号：1008-0457（2021）02-0001-08

国际DOI编码：10.15958/j.cnki.sdnyswxb.2021.02.001

Abstract：In order to provide theoretical basis for prevention and control of tobacco black spot stalk，this study explored the biological characteristics of Phoma omnivirens and tested its virulence determination.The biological characteristics of P.omnivirens was analyzed by hypha growth rate method，and the effect of twelve fungicides on the pathogen were also determined.The results showed that Nutrient Agar（NA），Oatmeal Agar（OMA） and Potato Dextrose Agar（PDA） were the most suitable culture medium for the growth of P.omnivirens.The mycelium could grow in the temperatures ranging from 5 ℃ to 30 ℃，30 ℃ was the optimum temperature for mycelium growth，and the mycelium grew the slowest at 5 ℃.The mycelium grew fastest at pH 10 in PDA.Different light conditions did not significantly influence the growth of mycelium.The optimal carbon source for the medium were sucrose，and the best nitrogen sources were potassium nitrate and calcium nitrate，respectively.The lethal temperatures of mycelium was 58 ℃ for 10 min.Among the 12 fungicides，3% Zhongshengmycin had the best inhibitory effect with the lowest EC50 of 0.9419 mg/L;followed by 0.3% Tetramycin and 80% Mancozeb，with EC50 of 2.6940 mg/L and 2.7917 mg/L，respectively.These three fungicides can be used to control tobacco black spot stalk in the field.

Keywords：tobacco black spot stalk;Phoma omnivirens;biological characteristics;virulence determination

17世纪初叶，烟草开始传入我国[1-2]，成为我国重要的经济作物之一，在我国的经济发展上起到了极大的促进作用。但烟草病害的发生制约了烟叶产量的提高，使烟农收入受到严重影响。截止2002年，已报道116种烟草病害，其中79种为侵染性病害，37种为非侵染性病害[3-4]。烟草茎点病是一种偶发性的真菌性病害，可危害黄花烟和普通烟，田间大多于成株期危害烟株茎基部，使养分和水分的疏导受阻，叶片早衰，严重时茎秆和叶片枯死，造成烟叶产量下降、品质降低[5]。研究烟草茎点病菌的生物学特性、筛选高效抑制病原菌生长的杀菌剂对了解烟草茎点病的发生规律和生产上有效防治该病害具有重要意义。……