摘要
[目的]明确甘薯腐烂溃疡病病原菌茄镰孢菌(Fusarium solani)的生物学特性及其致病条件。[方法]采用菌丝生长速率法、菌丝称重法、孢子萌发计数法和人工接种薯块的方法,对影响病原菌生长和侵染的碳源、氮源、pH值和温湿度条件进行了研究。[结果]碳源中的葡萄糖、乳糖和氮源中的蛋白胨、硝酸钾促进菌丝生长作用较强,碳源中的麦芽糖和氮源中的蛋白胨促进菌丝生长量作用较强,碳源中的乳糖、葡萄糖和氮源中的硝酸钾、甘氨酸、蛋白胨处理的孢子萌发率较高;菌丝生长的最适pH为5~6,最适温度为28℃;孢子萌发的最适温度为25℃,致死温度为54℃处理10min;在9~19℃温度范围内,9℃处理的菌丝生长最慢,24h孢子不能萌发;在30%~70%相对湿度范围内,30%相对湿度的病害发病程度较轻;在11~19℃范围内,11℃处理病害发病程度较轻。[结论]综合分析,甘薯茄镰孢菌菌丝生长和孢子萌发的最适碳源为乳糖和葡萄糖,最适氮源为蛋白胨和硝酸钾;菌丝在28℃条件下生长最快,最适pH值为5~6;孢子在25℃萌发率最高,致死温度为54℃处理10min。在模拟贮藏温湿度条件下,随着温度和湿度的降低,孢子萌发和菌丝生长受到抑制,病害发展显著减轻。
[Objective]The aim of this study was to observe the biological characteristics and infection conditions of Fusarium solani,causing Fusarium Root Rot and Stem Canker of sweetpotato(Ipomoea batatas L.[Methods]The mycelial growth rate,dry weight,germination rate and artificial inoculation on storage root were adopted to investigate the effects of carbon sources,nitrogen sources,pH and temperature and moisture on growth of hyphae and germination of conidia and infection of the tested fungus.[Result]Lactose,glucose,peptone and KNO3 could dramatically increase the growth rate of mycelia;maltose and peptone could promote the dry weight of mycelia;lactose,glucose,KNO3,glycine and peptone could accelerate the germination of conidia.The most suitable pH and temperature for the growth of hyphae were pH 5~6and 28℃,respectively;the temperature for the conidial germination was 25℃.The conidial lethal temperature was 54 ℃ for 10 minutes.From tested 9 ℃ to 19 ℃,the mycelia growth was the slowest and the conidia could not germinate after 24 hat the storage temperature of 9℃.The infection damages were milder at the relative humidity(RH)of 30% within the scope of RH 30%~70% and the temperature of 11℃ within the scope of 11~19 ℃.[Conclusion]The most suitable conidial germination and hyphal growth of F.solani,carbon sources were lactose and glucose,nitrogen sources were peptone and KNO3.For the growth of hyphae,optimum pH and temperature were 5~6,28 ℃,respectively.The suitable temperature for the conidial germination was 25 ℃.The conidial lethal temperature was 54℃for 10 minutes.In the simulation of storage temperature and moisture,conidial germination andmycelial growth were suppressed,disease development was dramatically slowed down when the temperature and relative humidity decreased.
引文
[1]Loebenstein G,Thottappilly G.The sweetpotato[M].New York:Springer Science and Business Media BV,2009:9-103.
[2]Wang RY,Gao B,Li XH,et al.First report of Fusarium solani causing Fusarium root rot and stem canker on storage roots of sweet potato in China[J].Plant Disease,2014,98(1):160.
[3]王容燕,高波,陈书龙,等.河北省甘薯镰孢菌腐烂与溃疡病的病原鉴定[J].植物保护学报,2016,43(2):241-247.
[4]沈丽淘,李平,王学贵,等.山药根腐病菌(Fusarium solani)的生物学特性[J].四川农业大学学报,2012,30(3):313-318.
[5]刘丽云,刘晓林,刘志恒,等.辣椒根腐病菌生物学特性研究[J].沈阳农业大学学报,2007,38(1):54-58.
[6]杨志敏,毕阳,李永才,等.马铃薯干腐病菌硫色镰孢的生物学特性[J].菌物学报,2012,31(4):574-583.
[7]方中达.植病研究法[M].北京:中国农业出版社,2007:62-145.
[8]Nielsen L W,Moyer J W.A Fusarium Root Rot of Sweetpotatoes[J].Plant Disease,1979,63:400-406.
[9]杨冬静,孙厚俊,赵永强,等.甘薯黑斑病菌的生物学特性研究及室内药剂筛选[J].西南农业学报,2013,26(6):2336-2339.
[10]Arancibia R A,Main J L,Clark C A.Sweetpotato tip rot incidence is increased by preharvest applications of ethephon and reduced by curing[J].Hort Technology,2013,23(3):288-293.
[11]Da Silva W L,Clark C A.Infection of sweetpotato by Fusarium solani and Macrophomina phaseolina prior to harvest[J].Plant Disease,2013,97(12):1636-1644.