磁化水对盐胁迫下黄瓜生长和生理特性的影响

为探究磁化水浇灌对盐胁迫下黄瓜幼苗生长和生理特性的影响,采用人工气候室内进行的二因素二水平砂培试验,即2个磁化水水平(D:蒸馏水、M:磁化蒸馏水)和2个盐处理水平(Na0:0 mmol/L,Na1:100 mmol/L NaCl),共4个处理,研究了盐胁迫下磁化水浇灌对黄瓜幼苗生长、水分关系、光合气体交换、抗氧化能力、养分(N,P和K)及Na含量等的影响。结果表明:(1)无论在非盐胁迫和盐胁迫下,浇灌磁化水均具有改善黄瓜幼苗生长及/或生理活动的作用。磁化水在盐胁迫下改善黄瓜生长和生理活动的作用大于非盐胁迫下,且随盐胁迫或磁化水处理时间的延长,磁化水的效应增加。(2)盐胁迫下,磁化水浇灌改善黄瓜幼苗生长的主要生理机制在于:增加了黄瓜幼苗根系生长,改善了叶片水分关系,增加了叶片叶绿素含量、光合速率和水分利用效率,增强了叶保护酶活性从而降低了叶细胞膜受伤害程度,降低了根、茎和叶中的Na含量从而增加K⁺/Na⁺比。研究结果为磁化水用于次生盐渍化土壤上生长的黄瓜灌溉提供了理论依据。

Effects of Magnetized Water Irrigation on the Growth and Physiological Characteristics of Cucumber Seedlings Under Salt Stress

In order to explore the effects of magnetized water irrigation on the growth and physiological characteristics of cucumber seedlings under salt stress, a sand culture experiment with 2 factors × 2 levels design was set up in the phytotron, including four treatments with two magnetized water levels(D: distilled water, M: magnetized distilled water)and two salt levels(Na0:0 mmol/L, Na1:100 mmol/L NaCl), the effects of magnetized water irrigation on the growth, water relation, photosynthetic gas exchange, antioxidant capacity, N, P, K and Na contents of cucumber seedlings under salt stress were studied. Results indicated that:(1)magnetized water irrigation improved the growth and/or physiological activities of cucumber seedlings under both non-salt and salt stress; the positive role of magnetized water irrigation was larger under salt stress than that under non-salt condition, and increased with the longer application of magnetized water and increased duration of salt stress;(2)the physiological mechanism of magnetized water use improving the growth of cucumber seedlings was mainly attributed to enhancing root growth, improving leaf water relation, increasing leaf chlorophyll content, net photosynthetic rate and instantaneous water use efficiency, decreasing the damaged degree of cellular membrane by stimulating protective enzyme activities, decreasing Na⁺ content in roots, stems and leaves and increased K⁺/Na⁺ ratio of cucumber seedlings. The study provides theoretical basis of irrigating the cucumber grown in secondary salinization soil with magnetized water.