磁化微咸水灌溉对欧美杨I-107离子稳态的影响

Ionic homeostasis of Populus × euramericanna ‘Neva' influenced by irrigation with magnetized brackish water

为探究微咸水磁化处理条件下植株的离子稳态特征,以欧美杨I-107一年生扦插苗为试材,于生长季节分别采用Hoagland营养液和4.0 g·L^(-1)Na Cl微咸水,经磁化处理后连续灌溉30 d.采用原子吸收分光光度法对叶片和根系中K^+、Na^+、Ca^(2+)和Mg^(2+)含量进行测定,分析离子平衡系数(K)和根-叶之间的离子选择性运输系数(S_(Xi,Na)).结果表明:与非盐分胁迫处理相比,盐分胁迫处理根系和叶片中Na^+和Ca^(2+)含量及S_(K,Na)、S_(Mg,Na)升高,K^+和Mg^(2+)含量、K^+/Na^+及SCa,Na降低.与非磁化微咸水灌溉处理相比,磁化微咸水灌溉处理的根系和叶片中Na^+含量降低、K^+含量及K^+/Na^+提高;根系和叶片中Ca^(2+)含量降低、Mg^(2+)含量提高;磁化微咸水灌溉处理中K提高,且叶片中K值显著高于根系;S_(K,Na)和SMg,Na较非磁化微咸水灌溉提高,S_(Ca,Na)较其降低.磁化微咸水灌溉中根系和叶片Na^+积累量减少,K^+、Ca^(2+)和Mg^(2+)含量增加,且维持了较高水平的K^+/Na^+,这有利于植株整株水平生理代谢的调控.因此,盐分胁迫下磁化作用可通过调节离子的选择性吸收和运输来维持植株体内的离子平衡.

The research aimed to study the characteristic of ionic homeostasis of annual seedlings of Populus ×euramericanna under irrigation with non-magnetized and magnetized 0 or 4.0 g·L^（-1）Na Cl solution for 30 days in the growing season. The ion contents of K~＋,Na~＋,Ca^（2＋）and Mg^（2＋）in the leaves and roots were measured by atomic absorption spectrophotometry（ AAS）. The ion homeostasis coefficient（ K） and the ion selective transport coefficient（ S_（Xi,Na）） from root system to leaves were analyzed. Compared with the unsalted treatment,the ion contents of Na~＋and Ca^（2＋）,S_（K,Na）and SMg,Na increased in leaves and roots under Na Cl stress,while the K~＋and Mg^（2＋）ion content,the ratio of K~＋/Na~＋and SCa,Nadecreased. Compared with the non-magnetized Na Cl solution（ NM）,the magnetized Na Cl solution（ M） made leaves and roots maintain lower content of Na~＋but higher content of K~＋and the K~＋/ Na~＋. Compared with the NM,the content of Ca^（2＋）decreased while that of Mg^（2＋）increased in the M. In M,K was higher than that in NM,and there was significant increase in the leaves than that in the roots. The ratios of S_（K,Na）and S_（Mg,Na） in leaves and roots in M were higher than those in NM,while the ratio of SCa,Nawas lower. The magnetized NaCl solution decreased Na~＋content,increased K~＋,Ca^（2＋）and Mg^（2＋）content,and maintained higher K~＋/ Na~＋,which was beneficial for the physiological metabolism of the whole plant. So,the magnetic effect could promote the re-establishment of ionic homeostasis by ions selective absorption and transportation under NaCl stress.