【作者】 杨佳丽； 余挺； 余辰； 郑晓冬； 曾丽珍； 邵灵霄； 周涛；

【Author】 Yang Jiali;Ting Yu;Yu Chen;Zheng Xiaodong;Zeng Lizhen;Shao Lingxiao;Zhou Tao;College of Biosystems Engineering and Food Science,Fuli Institute of Food Science,Zhejiang Key Laboratory for Agro-Food Processing,Zhejiang R & D Center for Food Technology and Equipment,Zhejiang University;

【机构】 浙江大学生物系统工程与食品科学学院馥莉食品研究院浙江省农产食品加工重点实验室浙江省食品技术与装备研发中心；

【摘要】 L-谷氨酸(Glu)在生物体内的氨基酸代谢过程中占据重要地位,并参与动物、植物和微生物中的许多重要化学反应。目前,关于其在植物病害防治领域的研究尚未见有报道。本实验研究了Glu对梨果实青霉病抗性的诱导作用规律,并初步探讨了其生物学机制。结果显示,1~1000μg/mL Glu在梨果实伤口处对由P.espansum引起的青霉病没有直接抑制作用,在PDA固体培养基和PDB液体培养基中亦不能显著抑制P.espansum的生长;而100~1000μg/mL Glu在预先处理伤口组织24~36h后,可以显著降低梨果实青霉病的发病率及病斑直径,且Glu诱导处理后再接入P.espansum果实组织的苯丙氨酸解氨酶(PAL)、过氧化氢酶(CAT)、过氧化物酶(POD)、多酚氧化酶(PPO)活性相比Glu或P.espansum单独处理组均呈现显著而快速提高的趋势。上述结果表明,Glu能够诱导梨果实产生抗性可能与其能激发果实相关防御酶系活性和Priming机制有关。此外,Glu处理组的品质指标与对照组相比也无发生显著性变化,显然其未对梨果实品质产生不良影响。更多还原

【Abstract】 L-glutamate(Glu) occupies a pivotal role in amino acid metabolism and orchestrates crucial metabolic functions.In this study,this potential natural compound,for the first time,was investigated for its influence on suppressing the blue mold rot caused by Penicillium expansum in pear fruit without adverse influence on its edible quality.The results indicated that Glu had little direct antifungal activity against P.expansum in vivo when the time interval between Glu treatment and pathogen inoculation was within 6 h.Similarly,Glu,at a concentration ranging from 1 to 1000μg/ml,was found to show little inhibition effect on the spore germination in PDB and the survival of P.expansum on PDA.By contrast,Glu,at 100~1000μg/ml,stimulated remarkable resistance of pear fruit to the blue mould rot.When Glu was applied24-36 h before inoculation with P.expansum,disease incidence and disease severity in pear fruit significantly decreased.The activities of defense-related enzymes,including phenylalnineammonialyase(PAL),catalase(CAT),peroxidase(POD) and polyphenoloxidase(PPO) were markedly and/or promptly enhanced in the treatment with Glu and inoculation with P.expansum compared with those that were treated with Glu or inoculated with pathogen alone.Thus we assume that the efficacy of Glu in inhibiting fungal disease may be related to induction of the fruit natural resistance via priming activation and defensive enzyme activity.更多还原