外源一氧化氮对NaCl胁迫下番茄幼苗生理影响

 【目的】探明NO对NaCl胁迫下番茄（Lycopersicon esculentum Mill.）幼苗的生长和叶片氧化损伤具有保护作用。【方法】在100 mmol·L-1 NaCl胁迫下，研究了0.05～0.8 mmol·L-1外源NO供体硝普钠 （SNP）处理对番茄幼苗生长、叶片保护酶活性和氧化损伤的影响。【结果】0.1 mmol·L-1 SNP处理缓解NaCl胁迫伤害的效果最好，显著提高了番茄幼苗生长，叶片叶绿素含量，保护酶SOD、POD、CAT、APX活性，脯氨酸和可溶性糖含量。显著降低了MDA和O2-含量。【结论】外源NO缓解番茄幼苗NaCl胁迫具有剂量效应，以0.1 mmol·L-1 SNP的效果最好，从而增强植株的耐盐性。

Physiological Effects of Exogenous Nitric Oxide in Tomato Seedlings Under NaCl Stress

【Objective】The purpose of this paper is to clarify the protective effects of nitric oxide (NO) on seedling growth and leaf oxidative damage in NaCl stressed tomato (Lycopersicon esculentum Mill.). 【Method】Under 100 mmol·L-1 NaCl stress condition, the effects of sodium nitropprusside (SNP, an exogenous nitric oxide donor) at the concentrations of 0.05-0.8 mmol·L-1 on the growth, leaf protective enzymatic activities and oxidative damage in tomato seedlings were investigated.【Result】The best effect on the alleviation of NaCl stress damage was observed in the treatment of 0.1 mmol·L-1 SNP. At this concentration, the seedling growth, chlorophyll content, activities of protective enzymes (including SOD, POD, CAT and APX) in leaves, and contents of proline and soluble sugar in leaves were significantly increased, while malondialdehyde (MDA) content and O2- producing rate in leaves were significantly decreased.【Conclusion】The above results indicated that dosage effect of exogenous nitric oxide donor (SNP) existed on the alleviation of NaCl stress in tomato seedlings, and the best alleviating effect on NaCl stress damage was 0.1 mmol·L-1 SNP, which elevated the salt tolerance of plants.