高温胁迫对蜜环菌生长特性的影响

Effects of High Temperature Stress on Growth Characteristics of Armillaria

目的探究高温胁迫对不同蜜环菌生长特性的影响,为筛选耐高温的优良蜜环菌菌株提供指导。方法以14株不同天麻产区的蜜环菌为实验材料,观察各蜜环菌菌株的生长特性并进行表型分类;采用rDNA-IGS序列分析进行分子鉴定,进一步确定供试菌株的亲缘关系;以23℃条件为对照(CK),30℃为高温胁迫,记录各菌株生长速度,生物量,菌索长度等指标。结果14株蜜环菌均与高卢蜜环菌Armillaria gallica相似性最高,亲缘关系最相近;但不同天麻产区的蜜环菌菌株生长特性存在明显差异,将14株蜜环菌分为Ⅳ个类群,其中生长状态:第Ⅰ类群>第Ⅱ类群>第Ⅲ类群>第Ⅳ类群;高温胁迫后,各菌株对高温的耐受性也存在明显差异,表现在菌索平均生长速度GZ16>SX1>GZ1;相对菌索长度GZ16>SX1>GZ3;相对生物量GZ16>SX4>GZ1>HB1>AH2;生长状态GZ16>SX1>GZ1。结论高温胁迫下,GZ16在生长速度,相对菌索长度,相对生物量及生长状态等均最优,SX1,GZ1菌株次之。表明菌株GZ16,SX1,GZ1耐高温能力较强,且这3个菌株在正常温度下生长特性也优良,适宜全国主要天麻产区生产。

Objective To explore the effects of high temperature stress on the growth characteristics of different Armillaria strains,and to provide guidance for screening excellent Armillaria strains with high-temperature resistance.Method 14 strains of Armillaria from different G.elata producing areas were used as experimental materials to observe the growth characteristics and conduct phenotypic classification for the strains.rDNA-IGS sequence analysis was used for molecular identification to further determine the genetic relationship of the tested strains.The strain growth rate,biomass,mycelial length and other indicators under the condition of 23℃(CK)and 30℃ high temperature stress were recorded.Result All the 14 strains of Armillaria had the highest similarity and the closest relationship with Armillaria gallica,but there were significant differences in growth characteristics among different G.elata producing areas.The 14 strains of Armillaria were classified into Ⅳ groups,and the growth status was group Ⅰ>group Ⅱ>group Ⅲ>group Ⅳ.After treatment with high temperature stress,the tolerance of each strain to high temperature also showed obvious differences,as shown in the average growth rate of the mycelial was GZ16>SX1>GZ1.The rank of relative mycelial length was GZ16>SX1>GZ3 and the relative biomass was GZ16>SX4>GZ1>HB1>AH2.Conclusion Under high temperature stress,GZ16 was best in growth rate,relative length of mycelial,relative biomass and growth state,followed by SX1 and GZ1 strains.The results indicate that strains GZ16,SX1 and GZ1 have the strong resistance to high temperature and excellent growth characteristics at normal temperature,so these three strains are suitable to be produced in main G.elata producing areas in China.