黑木耳栽培种质对高温胁迫的响应

Response of Auricularia auriculata Germplasm After High Temperature Stress

以黑木耳菌株“沈8-9”为试材,采用测定不同时间高温胁迫下菌丝体内丙二醛(MDA)含量和超氧化物歧化酶(SOD)、多酚氧化酶(PPO)、过氧化氢酶(CAT)、谷胱甘肽还原酶(GR)活性的试验,观察不同时间高温胁迫后和恢复培养一段时间后菌落的生长速率、生长势和菌丝显微形态,研究黑木耳栽培种质对高温胁迫的反应,以期为合理控制环境条件及抗高温品种的筛选提供参考依据。结果表明:不同时间的高温胁迫下,黑木耳栽培种质在氧化损伤程度、菌落形态和菌丝显微形态特征上均有变化。随着胁迫时间的延长,菌丝MDA含量和SOD、PPO、CAT等3种酶活性的变化趋势明显不同,GR活性发生变化不显著。从菌落形态和生长势情况来看,随着胁迫时间的延长,菌丝生长速度逐渐减小,菌落边缘菌丝发黄,稀疏,萎缩严重。从光学显微形态来看,随着胁迫时间的延长,菌丝体内产生大量黑色素,部分尖端菌丝扭结成团,部分菌丝断裂、自溶,有菱形、六角形或不规则形晶体产生,菌丝分支频率随着胁迫时间的延长而逐渐降低。从电子显微形态来看,胁迫48h后,部分菌丝干瘪并皱缩;胁迫72h后,皱缩菌丝增多;胁迫96h后,皱缩菌丝越来越多,并有网絮状杂质产生。菌丝恢复能力为胁迫24h>胁迫48h>胁迫72h>胁迫96h。

The Auricularia auricularia strain‘Shen 8-9’was used as test material,the study on the response of Auricularia auricularia germplasm to high temperature stress was carried out by measuring the MDA content and activities of SOD,PPO,CAT and GR of hypha,though observing the growth rate,growth potential and microscopic morphology of hypha after different time of high temperature stress and after resuming culture for a period of time,in order to provide reference for reasonable control of environmental conditions,and the selection of varieties resistant to high temperature.The results showed that there were changes in oxidative damage degree,colony morphology and mycelial micromorphology of black fungus cultivars to high temperature stress at different times.With the prolongation of stress time,the content of MDA and the activities of SOD,PPO and CAT in mycelia were significantly different,while the activity of GR was not significantly changed.In the general scenario,colony hypha and growth potential were as follows,the growth rate of hypha gradually decreased,and the hypha at the colony edge became yellow,sparse,and atrophied seriously with the extension of stress time.The optical micromorphology was as follows,a large amount of melanin was produced in hypha,some tip hypha twisted into clusters,some hypha broke and had diamond,hexagonal,or irregular crystals,and the frequency of mycelia branching gradually decreased with the extension of stress time.The electron micromorphology showed that some hypha was shriveled and shrunken after 48hours stress.Wrinkled hypha increased after 72hours stress.More and more crumpled hypha and flocculent impurities were produced after 96hours of stress.The recovery ability of hypha was 24hours>48hours>72hours>96hours.