NaCl胁迫下六妹羊肚菌菌丝的生理响应及主成分分析

Physiological Response and Principal Component Analysis of Morchella sextelata Mycelia under NaCl Stress

为探究NaCl胁迫对六妹羊肚菌(Morchella sextelata)菌丝生长及生理指标的影响,以六妹羊肚菌作为实验材料,通过设置不同浓度(0、100、200、300、400和500 mmol/L)的NaCl固体培养基和液体培养基对六妹羊肚菌菌丝进行培养,并测定各组的菌丝生长指标、菌丝外观形态、生物量、菌丝质膜透性、渗透调节物质含量以及抗氧化酶活性等参数,分析不同程度NaCl胁迫对六妹羊肚菌菌丝生长和抗性生理的影响,并采用相关性分析和主成分分析的方法筛选不同NaCl浓度下六妹羊肚菌菌丝生长过程中的关键生理指标。结果表明,随着培养基中NaCl浓度的增加,六妹羊肚菌菌丝生长速度、生物量、菌丝直径和胞内多糖的含量呈现下降趋势,而渗透压和电导率则呈上升趋势;可溶性蛋白含量、丙二醛(MDA)含量、脯氨酸(Pro)含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性和过氧化氢酶(CAT)活性都随NaCl浓度的增加呈先升高后降低的趋势。200 mmol/L NaCl浓度下,丙二醛(MDA)含量、过氧化物酶(POD)活性和过氧化氢酶(CAT)活性出现峰值,脯氨酸(Pro)含量和超氧化物歧化酶(SOD)活性的峰值出现在300 mmol/L NaCl浓度,而可溶性蛋白含量的峰值出现在400 mmol/L NaCl浓度下。通过主成分分析发现,前3个主成分的累计贡献率为96.611%。其中,NaCl浓度在0~100 mmol/L时,指示性生理指标为生长速度、菌丝直径、干重、鲜重和胞内多糖;NaCl浓度在100~200 mmol/L时,指示性生理指标为丙二醛(MDA)含量、可溶性蛋白含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性和过氧化氢酶(CAT)活性;NaCl浓度在200~400 mmol/L时,指示性生理指标为脯氨酸(Pro)含量、可溶性蛋白含量和超氧化物歧化酶(SOD)活性。

Morchella sextelata was used as experimental material to explore the effects of NaCl stress on mycelia growth and physiological indexes.The mycelial growth index,mycelial morphology,biomass,mycelial membrane permeability,osmotic regulatory substance content and antioxidant enzymes of M.sextelata were measured under different concentrations of NaCl(0,100,200,300,400 and 500 mmol/L).The effects of different levels of NaCl stress on mycelial growth and resistance physiology of M.sextelata were analyzed.Correlation analysis and principal component analysis were used to screen the key physiological indexes during the mycelial growth of M.sextelata under different NaCl concentrations.The results indicated that as the concentration of NaCl in the medium increased,the mycelial growth rate,mycelial biomass,mycelial diameter and intercellular polysaccharide(IPS)content of M.sextelata showed a downward trend,while the osmotic pressure(OP)and electrical conductivity(EC)showed an upward trend.The soluble protein content,malondialdehyde(MDA)content,proline(Pro)content,superoxide dismutase(SOD)activity,peroxidase(POD)activity and catalase(CAT)activity all increased first and then decreased with the increasing of NaCl concentration.At 200 mmol/L NaCl concentration,the malondialdehyde(MDA)content,peroxidase(POD)activity and catalase(CAT)activity peaked,proline content and SOD activity peaked at 300 mmol/L salt concentration,while soluble protein content peaked at 400 mmol/L NaCl concentration.Through principal component analysis,the accumulative contribution rate of the first three principal components was 96.611%.Among them,when NaCl concentration was 0~100 mmol/L,the indicative physiological indexes were growth rate,mycelial diameter,dry weight,fresh weight and IPS content.When NaCl concentration was 100~200 mmol/L,the indicative physiological indexes were MDA content,soluble protein content,SOD activity,POD activity and CAT activity.When NaCl concentration was 200~400 mmol/L,the indicative physiological indexes were Pro content,soluble protein content and SOD activity.