扩展青霉菌侵染采后刺伤苹果的特性研究

Study on the Character of Penicillium expansum(Link) Thom Infecting Postharvest Apple of Needle-stick Injuries

目的:了解刺伤导致青霉菌侵染苹果的特性和评估伤口抗病性。方法:苹果刺伤后不同时间在伤口远近部位接种青霉菌。用过氧化氢(H2O2)诱导细胞死亡,用伤液诱导抗病性。检测病斑大小、腐烂率、木质素、总多酚含量,提取伤液进行青霉菌抑制试验。结果:迟接种青霉菌比早接种腐烂率低。刺伤虽能诱导伤口局部和远处产生抗病性,但远处的抗病性不强。H2O2诱导组织死亡,即使没有青霉菌侵染,也会导致伤口水浸状。如果接种青霉菌,就会显著加快腐烂。刺伤后木质素含量持续上升,总多酚含量高于对照。伤液虽不能抑制青霉菌,但浸涂伤液可以显著提高抗病能力。结论:如果防止伤口周边细胞死亡,推迟青霉菌接触时间,将有利于防止青霉菌侵染。

Objective： To find out about the character of Penicillium expansum（Link） Thom infecting postharvest apple of needle-stick injuries and estimate the disease resistance induced by wound. Method： Different positions of wounded apples were inoculated with P. expansum in different time after acupuncture. H2O2 was used to induce cell death and wound fluid was used to induce disease resistance. Lesion diameter, decay rate, Lignin and total polyphenol contents were detected. Wound fluid was extracted to do the antifungi experiment. Results： The decay rate decreased with the delay of the inoculation time. Needle-stick injuries could induce both local and distant disease resistance but the latter was not strong. Wounds looked like water immersion after the cell death induced by H2O2 even without the infection of P. expansum. If there was the existence of P. expansum, the decay would be significantly accelerated. Wound fluid could significantly improve the disease resistance which itself could not inhibit P. expansum. Conclusion： To prevent further death of the cells surrounding the wound and postpone the infection time of P. expansum could help prevent the infection of P.expansum.