摘要
以香菇(Lentinula edode)'豫香1号'为参试菌株,模拟夏季高温季节气温变化特点,设置15个高温胁迫处理:H1(30 ℃,12h)、H2(33 ℃,12 h)、H3(33 ℃,24 h)、H4(33 ℃,48 h)、H5(36 ℃,48h)、H6(39 ℃,4h)、H7(39 ℃,8h)、H8(39 ℃,12h)、H9(39 ℃,48h)及 H10～H15(36 ℃每天4h,连续 2、4、6、8、10、12 d),对照在25℃下培养(CK),研究高温胁迫对香菇菌丝生长、细胞形态,胞外漆酶、蛋白酶、纤维素酶活性,邻氨基苯甲酸合酶(TrpE)、6磷酸-海藻糖合成酶(TPS)、过氧化氢(H2O2)含量,活性氧(ROS)水平的影响.通过主成分分析选取关键生理指标,计算不同处理的高温胁迫指数(Z),根据Z值划分胁迫等级,引入胁迫积温指数(ATSI)建立高温和持续时间的定量关系.结果表明,随胁迫温度升高及时间延长,香菇菌丝生长速度降低,菌丝胞外漆酶和羧甲基纤维素酶活性下降,TrpE、TPS、H2O2含量和ROS水平上升.以H2O2、TrpE、TPS含量和胞外漆酶活性为关键指标,根据Z值将高温胁迫划分为4个等级,轻度(1.5＜Z≤3.0)、中度(3.0＜Z≤4.5)、重度(4.5＜Z≤6.0)、特重度(6.0＜Z).处理H1～H5和H10～H15的Z值与其ATSI值呈极显著正相关,Z值随ATSI值的变化较小;处理H6～H8的Z值与其ATSI值呈显著正相关,但Z值随ATSI值的变化较大;处理H9受高温胁迫后,菌丝完全不能恢复生长.研究结果可为香菇栽培温度调控管理及高温灾害防御提供参考.
Abstract
Using Lentinula edode cultivar'Yuxiang 1'as the subject,15 groups of heat stress treatments were set up to resemble temperature variations in summer:H1(30 ℃,12 h),H2(33 ℃,12 h),H3(33 ℃,24 h),H4(33 ℃,48 h),H5(36 ℃,48 h),H6(39 ℃,4 h),H7(39 ℃,8 h),H8(39 ℃,12 h),H9(39℃,48 h)and H10-H15(36 ℃,4ha day for 2,4,6,8,10,and 12 d,respectively).Incubation at 25℃ were set as the control(CK).Mycelia in different treatment groups were measured for mycelial growth,cell morphology,activities of extracellular laccase,protease and cellulase(CMC),contents of hydrogen peroxide(H2O2),o-aminobenzoic acid synthase(TrpE)and 6-phosphate-trehalose synthase(TPS),and reactive oxygen species(ROS)level.Key physiological indices were selected by principal component analysis,and the stress index Z was calculated for different treatments so as to categorize the stress levels.The stress accumulated temperature index ATSI was also used to establish a quantitative relationship between high temperature and duration.The results showed that with the increase of the stress temperature and time,the mycelial growth rate of'Yuxiang 1'decreased,and the contents of TrpE,TPS,H2O2 and ROS increased.Using contents of H2O2,TrpE and TPS,and extracellular laccase activity as the selected key indicators,the heat stress was classified into 4 grades as follows:mild(1.5＜Z≤ 3),moderate(3＜Z ≤ 4.5),severe(4.5＜Z ≤ 6)and extremely severe(6＜Z).The Z values of Hl-H5 and H10-H15 were extremely significantly positively correlated with their ATSI values,and the Z values varied little with the ATSI values.The Z values of H6-H8 were significantly positively correlated with their ATSI values,but the Z values vaired greatly with the ATSI values.The mycelia of H9 completely failed to resume growth after heat stress.These results provided a reference for the regulation and management of L.edodes growth temperature and prevention of high temperature induced losses in yield.
维普
万方数据