一株分离自番茄叶片的刀孢蜡蚧菌的鉴定、生物学特性及其对杀菌剂敏感性

Identification, Biological Characteristics and Fungicide Sensitivity of a Fungus Lecanicillium psalliotae Isolated from Tomato Leaves

从浙江省杭州市余杭区番茄种植基地番茄叶片中分离获得菌株HZ9111,经形态学和分子生物学鉴定为刀孢蜡蚧菌Lecanicillium psalliotae。该菌株菌丝在20-30℃均能正常生长,35℃停止生长,最适温度为25℃;光周期12L：12D及培养基pH 6.0的环境条件利于菌体生长。该菌株能利用多种碳、氮源营养,但存在一定的差异。其中,以蔗糖和牛肉浸膏培养基上菌丝生长较快（日平均生长速率分别为5.02和5.81mm/d）,在半乳糖和硝酸钾培养基上生长较慢（分别为2.36和4.27 mm/d）。菌株对14种常见杀菌剂的敏感性测定结果表明,250 g/L嘧菌酯悬浮剂、100 g/L氰霜唑悬浮剂、65%代森锌可湿性粉剂、75%百菌清可湿性粉剂、325 g/L苯甲·嘧菌酯悬浮剂对菌株HZ9111菌丝生长和孢子萌发的毒力较小,且中间三者在低浓度时可促进菌丝生长。本研究将为今后该菌的大规模生产或应用提供参考。

HZ9111, a strain isolated from tomato leaves cultivated in Hangzhou, Zhejiang Province, was identified as Lecanicillium psalliotae based on morphological and molecular characteristics. This fungus was able to grow at temperature between 20—30 ℃with an optimum of 25 ℃ and 12L：12D photoperiod, and an improved colony growth at acidulous level of pH 6.0. There were various kinds of carbohydrates and nitrogen known to provide growth of the fungal mycelium. Sucrose and beef extract were the best carbon and nitrogen source for mycelia with growth rates of 5.02 and 5.81 mm/d, respectively, while galactose and potassium nitrate provided growth rates of 2.36 and 4.27 mm/d, respectively. Among 14 fungicides, 250 g/L azoxystrobin SC, 100 g/L cyazofamid SC, 65% zineb WP, 75% chlorothalonil WP, and 325 g/L difenoconazole·azoxystrobin SC showed the lowest toxicity to mycelia growth and conidial germination. Meanwhile, three fungicides（cyazofamid, zineb and chlorothalonil） promoted mycelia growth when used at low concentrations. These results are important for the large scale production of the fungus.