高温胁迫对刺芹侧耳菌丝生长及其抗棘孢木霉能力的影响

摘要

The high-temperature tolerance is one of the most preferred indicators for evaluation of edible mushroom stressresistance.Five Pleurotus eryngii strains were used to investigate the effects of heat stress on the mycelial growth and their resistance to Trichoderma asperellum by detecting the colony growth rate,growth vigor,the hyphal morphological characters and the infection rate by T.asperellum.Results showed that the five P.eryngii strains responsed to heat stress differently.The mycelium growth recovered in 2-3 days after heat stress (37C),and the growth vigor became stronger or unchanging.The cell length of distal hyphae,hyphal diameter,hyphal growing rate and mycelium branching frequency reduced significantly.The variation in mycelium growth rate was linearly and positively correlated with the decline in the ability of resistance to T.asperellum.We found that the infection rate of cultivation bags inoculated with the mycelium of T.asperel/um attained 100％,while the infection rate was only 30％ using spore suspension as inoculum under heat stress at 35C for seven days.However,cultivation bags were uninfectious under treatment without heat stress.These results indicated that heat stress could reduce the resistance of P.eryngii to T.asperellum.%耐高温性是食用菌抗逆性评价的重要指标.选取5个刺芹侧耳菌株为材料,通过观测常温培养和高温胁迫后恢复培养菌落的生长速率、生长势、恢复生长时间、菌丝显微形态特征以及受棘孢木霉侵染情况,研究高温胁迫对刺芹侧耳菌丝生长及其抗棘孢木霉侵染能力的影响.结果表明,刺芹侧耳不同菌株对高温胁迫的响应存在差异.供试PDA培养的菌丝经高温胁迫(37℃,2d)后,菌丝恢复生长时间2-3d,生长势变壮或无变化,顶端菌丝细胞长度、直径、菌丝体分支频率和菌丝生长速率等均呈现不同程度的降低.菌丝生长速率变化与其抗棘孢木霉能力的下降呈正相关.在此基础上,模拟生产试验发现,长满菌丝的菌棒经高温胁迫(35℃,7d)后,接种棘孢木霉菌丝的侵染率变为100％,接种棘孢木霉孢子的侵染率变为30％;未经高温胁迫的菌棒,接种棘孢木霉孢子/菌丝,未发生侵染.本研究表明,高温胁迫导致刺芹侧耳菌丝抗棘孢木霉侵染能力的下降.本研究将为科学指导食用菌菌种繁育、菌棒生产提供数据支撑,为食用菌育种提供基础数据.