摘要
用类黄酮含量分别为0.25、0.50、0.75 mg/m L的银杏叶提取液(extract of Ginkgo biloba leaves,EGb)通过损伤接种的方法处理猕猴桃,以无菌水为对照,24 h后接种扩展青霉(Penicillium expansum)孢子悬浮液,通过测定病斑直径和发病率观察EGb诱导猕猴桃抗性的效果;用类黄酮含量为0.50 mg/m L的EGb处理猕猴桃后接种青霉孢子悬浮液,定期取样测定抗病相关防御酶、病程相关蛋白、类黄酮、总酚及丙二醛含量的变化。结果表明:0.50 mg/m L的EGb能有效控制猕猴桃果实接种青霉菌后的发病率,抑制病斑扩展,提高猕猴桃果肉多酚氧化酶(PPO)、过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)、几丁质酶(CHI)和β-1,3-葡聚糖酶(GLU)活性,促进总酚和类黄酮的积累,同时降低膜脂过氧化程度,减少丙二醛的产生,其中以EGb处理后再接种青霉菌的抗性诱导效果最好,表明0.50 mg/m L的EGb可能以Priming机制诱导猕猴桃对青霉菌的抗性。
The present work was conducted to investigate the effects of treatment with Ginkgo biloba L. leaf extract（EGb） on disease resistance against Penicillum expansum infection and the possible mechanisms involved. The kiwifruit were treated with EGbs containing 0.25, 0.50 and 0.75 mg/m L flavonoids and distilled water（control） after harvest, respectively. Twenty-four hours after the treatment with EGb, the fruit were inoculated with 20 μL of conidial suspension of Penicillium expansum（1 × 10^4 spores/m L） and incubated at 23 ℃ and 85%–90% relative humidity（RH） for disease development. In addition, to investigate the resistance mechanism against Penicillum expansum infection, kiwifruit with four treatments namely EGb, P. expansum, EGb ＋ P. expansum and control were tested. Results showed that disease incidence and lesion diameter in kiwifruit after the inoculation were significantly（P〈0.05） reduced by 0.50 mg/m L EGb during the incubation. Moreover, the activities of polyphenol oxidase, peroxidase, phenylalnine ammonialyase, chitinase and β-1,3-glucanase as well as the content of total phenolics and flavonoids were markedly and/or promptly enhanced in the EGb ＋ P. expansum treatment compared with those treated with EGb or inoculated with pathogen alone. Besides, the content of MDA was decreased by EGb treatment. Its mechanisms may be closely correlated with the induction of fruit resistance by priming activation upon challenge with pathogen. These results suggest that the efficacy of EGb at 0.50 mg/m L on controlling blue mold decay in kiwifruit may be related to the priming of defense responses.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2016年第6期242-247,共6页
Food Science
基金
国家大学生创新训练计划项目(201510712010)
杨陵示范区科技计划项目(2015NY-14)
关键词
'秦美’猕猴桃
扩展青霉
银杏叶提取液
诱导抗性
‘Qinmei＇ kiwifruit
Penicillum expansum
Ginkgo biloba L.leaf extract（EGb）
induced resistance
