热水处理控制柠檬绿霉病及其抑菌机理初探

目的针对采后柠檬绿霉病问题,探究热水处理对采后柠檬绿霉病的控制效果及离体条件下对柠檬指状青霉的抑菌机理。方法以‘尤力克’柠檬为实验材料,研究不同温度和不同时间热水处理对柠檬果实绿霉病的控制效果,并在离体条件下探索热水处理对指状青霉活力和致病力的影响。结果从具有典型发病症状的柠檬果实上分离得到指状青霉。筛选出柠檬果实适宜的热水处理条件为53℃热水浸泡3 min,该处理组能够有效控制柠檬采后绿霉病,果实在贮藏5 d时的发病率和病斑直径分别降低93%和97%。在离体条件下,热水处理能够显著抑制指状青霉菌落的扩展,改变其细胞膜通透性,且热水处理后的指状青霉回接发病率显著降低(P<0.05)。结论该实验中,采用53℃热水浸泡3 min处理对指状青霉引起的柠檬果实绿霉病控制效果显著,在离体条件下采用热水处理降低了指状青霉的活力和致病力。

Effects of Hot Water Treatment on Green Mold Control of Lemon Fruits and Its Inhibition Mechanism

The work aims to investigate the effect of hot water treatment on green mold control of harvested lemon fruits and the inhibition mechanism of Penicillium digitatum(P.digitatum)in vitro in view of the green mold of harvested lemon.With Citrus limon(L.)Burm as the experimental material,the effect of hot water treatment at different temperatures and time on the control of lemon fruits'green mold was studied,and the effect of hot water treatment on the viability and pathogenicity of P.digitatum in vitro was explored.The pathogen was isolated from the lemon fruit with typical symptoms of green mold and identified as P.digitatum.The suitable hot water treatment conditions at 53℃ for 3 minutes could effectively control the green mold of harvested lemon compared with the control group,the disease incidence and lesion diameter of lemon fruits were respectively reduced by 93% and 97% after 5 d storage.In vitro,the growth of P.digitatum could be significantly inhibited by hot water treatment,its cell membrane permeability could be changed,and the inoculated disease incidence of P.digitatum treated by hot water was remarkably reduced(P<0.05).In this experiment,the hot water treatment conditions at 53℃ for 3 min can significantly control green mold of lemon fruits caused by P.digitatum and decrease the viability and pathogenicity of P.digitatum in vitro.