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作 者 ：李晓峰 王俊玲 李林妍 谢鑫 高志奎

期 刊 ：植物营养与肥料学报 2013年 19卷 5期 页码：1264-1271

关键词：韭菜；硫磺；水杨酸；硝酸盐累积；氮代谢；

Keywords:Chinese chive, sulfur, salicylic acid, nitrate accumulation, nitrogen metabolism,

摘 要 ：以3年生韭菜为试验材料，研究了不同浓度的硫磺（S，土施）和3 mmol/L水杨酸（SA，叶面喷施）配施对韭菜硝酸盐含量、氮代谢关键酶活性和叶绿素荧光参数的影响。结果表明，韭菜鲜重、硝酸盐含量、硝酸还原酶活性（NRA）、PSII 最大光化学量子产量（Fv/Fm）、电子传递速率（ETR）和可溶性蛋白含量均与硫磺和水杨酸的配施浓度有密切关系，与对照相比，7.2 kg/hm²的硫和 3 mmol/L 的水杨酸配施处理韭菜叶片的硝酸盐含量明显降低，降幅为16.6%；鲜重、NRA、Fv/Fm、ETR和可溶性蛋白含量分别提高了10.7%、12.3%、10.1%、21.2% 和 4.2%；谷氨酸丙酮酸转氨酶（GOT）和谷氨酸草酰乙酸转氨酶（GPT）活性却随着硫浓度的增加呈现出逐渐增加的趋势，当硫浓度为 54 kg/hm² 时，GOT和GPT的活性达到最高，分别比对照增加了13.6% 和 9.4%。由此可以看出，适宜浓度的硫磺和水杨酸配施可促进韭菜叶片氮代谢中硝酸盐的还原与同化，同时调动转氨作用的积极协同配合，促进了硝态氮转化为游离氨基酸和可溶性蛋白，这可能是硫磺和水杨酸配施降低韭菜硝酸盐累积的一个重要原因。

Abstract: Effects of sulfur (S) and exogenous salicylic acid (SA) on accumulation of nitrate, the key enzyme activities of nitrogen metabolism and chlorophyll fluorescence of Chinese chive were studied to understand the effects of S and SA on nitrate accumulation and nitrogen metabolism. The results indicate that there are significant concentration effects on the fresh weight, nitrate content, the activity of nitrate reductase（NRA）, the maximal photochemical efficiency （Fv/Fm）, the apparent electron transport rate （ETR）and soluble protein content in Chinese chive. Compared with the control, the nitrate content with 7.2 kg/ha S and 3 mmol/L SA treatment is reduced by 16.6%, while the fresh weight of Chinese chive, NRA, Fv/Fm, ETR and soluble protein content are increased by 10.7%, 12.3%, 10.1%, 21.2% and 4.2%, respectively. The activities of glutamicoxaloacetic transaminase （GOT） and the glutamatepyruvatetransaminase （GPT） are increased gradually with the increase of S concentration. The GOTA and GPTA are highest under S 54 kg/ha and are increased by 13.6% and 9.4% respectively compared with the control. In conclusion, S and SA obviously improve nitrate reduction and assimilation, which, meanwhile, bring transaminations into play vigorously, and promote turning NO^-₃ into free amino acid and dissolvable protein. Improvement of nitrate reduction and assimilation might be a key reason for reducing nitrate accumulation into the vacuole of Chinese chive.

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