盐胁迫下盐地碱蓬根系分泌物中化合物的种类和含量研究

Components and Contents of Compounds in Root Exudates of Suaeda salsa under Salt Stress

在植物的抗逆机理、耐盐基因开发和改善土壤微环境等方面,研究根系分泌物具有重要意义。为了更深入地了解盐地碱蓬(Suaeda salsa)根系分泌物与土壤含盐量的关系,于2020年7月25日,在黄河三角洲土壤含盐量存在显著差异的3处盐沼的盐地碱蓬群落区中,采集生长状态一致的盐地碱蓬全株样品,利用Agilent 7890A/5975C气相色谱质谱联用仪,鉴定盐地碱蓬根系分泌物中化合物的种类和测定其含量。研究结果表明,在土壤含盐量分别为1.5 g/kg、3.5 g/kg和7.0 g/kg条件下,盐地碱蓬根系分泌物中的化合物种类分别为45种、84种和45种,包括酯类、胺类、酮类、苯类、吲哚类、烷烃类、噻唑类、酚类、酸酐类、醛类、酸类、烯类、腈类、醇类、醚类、醌类、吡喃类、盐类和抗氧化剂化合物,而且都以烷烃类化合物的种类居多;随着土壤含盐量的增大,盐地碱蓬根系分泌物中的烷烃类化合物的含量逐渐增大,土壤含盐量为7.0 g/kg条件下的烷烃类化合物含量(54.040%)为盐地碱蓬根系分泌物中各类化合物含量的最大值,酸类和烯类等化合物的含量在不断减小,酯类、酮类、苯类、酚类和噻唑类化合物的含量都在土壤含盐量为3.5 g/kg时最小;随着土壤含盐量的增大,盐地碱蓬的代谢途径发生了变化,通过产生新的化合物或者阻断某种化合物的分泌来适应盐胁迫。

It is important to study root exudates in the aspects of plant anti-stress mechanism,salt tolerant gene development and soil microenvironment improvement.In order to further understand the relationship between contents of compounds in root exudates of Suaeda salsa and soil salt content,on July 25,2020,in Suaeda salsa community area of 3 salt marshes with significant differences in soil salt content in Yellow River Delta,the whole plant samples of Suaeda salsa with consistent growth status were collected and treated.The Agilent GC-MS(7890A/5975C)was used to analyze the components and contents of root exudates.The results showed that the types and contents of compounds in root exudates of Suaeda salsa were significantly affected by the soil salt content.Under soil salt contents were 1.5 g/kg,3.5 g/kg and 7.0 g/kg,there were 45,84 and 45 kinds of compounds in the compounds in root exudates of Suaeda salsa,respectively.A variety of compounds were measured from the root exudates,such as esters,amines,ketones,benzenes,indoles,alkanes,thiazoles,phenols,anhydrides,aldehydes,acids,alkenes,nitriles,alcohols,ethers,quinines,pyrans,salts and antioxidants.The alkanes contents were larger in the majority of the samples.With the increase of soil salt concents,the contents of alkanes in the root exudates of Suaeda salsa gradually increased.The content of alkane compounds(54.040%)was the maximum content of various compounds in the root exudates of Suaeda salsa under soil salt content of 7.0 g/kg.The acids and alkenes contents constantly decreased with the increase of soil salt content.The contents of esters,ketones,benzenes,phenols and thiazoles compounds reached the minimum values under soil salt content of 3.5 g/kg.With the increase of soil salt concent,the metabolic pathway of Suaeda salsa and adapt to salt stress by producing new compounds or blocking the secretion of some compounds.