甜樱桃采后贮藏环境中病原菌的分离鉴定及其致病力研究

Isolation,identification and pathogenicity study of pathogens during postharvest storage of sweet cherries

通过对甜樱桃采后储运、低温贮藏过程中腐烂病原菌的分离鉴定,得到6株病原菌,分别为互生链格孢(Alternaria alternata)NCPS1和NCPS2、链格孢(Alternaria sp.)NCPS3、扩展青霉(Penicillium expansum)NCPS4、禾生枝孢(Cladosporium herbarum)NCPS5和土栖帚枝霉(Sarocladium terricola)NCPS6;为了进一步确定环境因子对病原菌生长的影响,从生长速率、生长温度、生长pH值3个方面进行病原菌的生物学特性研究。结果表明,除菌株NCPS4外,其余5株菌的最适生长温度为25℃,最适生长pH为8;而菌株NCPS4的最适生长温度为30℃,在pH为2~10时均可生长;在0℃低温条件下仅NCPS1和NCPS2能正常生长。致病力比较结果表明,NCPS1、NCPS2、NCPS3为强致病力菌株,NCPS4、NCPS5为中等致病力菌株,NCPS6为弱致病力菌株。本研究为甜樱桃采后贮藏及配套保鲜技术的研发提供了重要的理论依据。

Six pathogens were isolated from postharvest sweet cherries during the transportation and lowtemperature storage.They were Alternaria alternata NCPS1 and NCPS2,Alternaria sp.NCPS3,Penicillium expansum NCPS4,Cladosporium herbarum NCPS5 and Sarocladium terricola NCPS6.Then,the biological characteristics of the six pathogens were studied in three aspects of growth rate,growth temperature and growth pH value.The results showed that the optimum growth temperature of NCPS1,NCPS2,NCPS3,NCPS5 and NCPS6 was 25℃,and the optimum pH value was 8.The optimum temperature of NCPS4 was 30℃,and it could grow at pH 2-10.Only NCPS1 and NCPS2 could grow at the low temperature of 0℃.The results of pathogenicity study showed that the six strains could be divided into strong pathogenic strains of NCPS1,NCPS2,NCPS3,moderate pathogenic strains of NCPS4 and NCPS5,weak pathogenic strains of NCPS6.In a word,it provides a scientific theory basis for the development of low-temperature storage and fresh-keeping technology of the postharvest sweet cherries.