NO浓度对小白菜生长和品质的影响

【目的】研究不同浓度NO气体对小白菜生物量、营养及抗氧化品质的影响，以期为大气NO污染的植物生态响应研究及农业生产提供理论依据。【方法】以小白菜为研究对象，采用密闭体系内土培的种植方式，研究浓度 (0、100、200和400 nL/L) 外源NO气施对小白菜生物量以及营养品质 (硝酸盐、可溶性糖和可溶性蛋白) 和抗氧化品质 (总酚、总黄酮和抗坏血酸) 的影响。【结果】1) 100、200和400 nL/L外源NO气体处理下，小白菜鲜重分别比对照增加了64%、42%和10%；干重增加了88%、61%和49%，以施加NO 100 nL/L最有利于的小白菜生长。2) 与不施加NO对照相比，施加外源NO气体100、200和400 nL/L使小白菜叶片硝酸盐含量分别减少了59%、76%和94%。NO气体也有利于小白菜可溶性糖以及可溶性蛋白含量的积累，并以100 nL/L时的促进效果最佳。3) 与对照相比，100、200和400 nL/L外源NO气体均促进了小白菜体内总酚、总黄酮及抗坏血酸的含量。【结论】适量外源NO气体对小白菜的生物量及品质均有一定的促进效果。综合来看，在蔬菜大棚生产中，施加NO 100 nL/L提高小白菜生长和品质的效果最好。

Effects of application of NO on plant growth and quality of pakchoi(Brassica chinensis L.)

【Objectives】Effect of different concentrations of nitric oxide (NO) on biomass, nutritional and antioxidant quality of pakchoi were studied to provide a theoretical basis for atmospheric NO-associated plant ecological responses and agricultural production.【Methods】A pot experiment was conducted using pakchoi (Brassica chinensis L.) as tested material in a closed growth chambers. The exogenous NO was applied in rate of 0 (control), 100, 200, and 400 nL/L in each chamber. The plant biomass was weighed, and the contents of nitrate, soluble sugar and soluble protein were determined, and the total phenolics, total flavonoids and ascorbic acid were analyzed.【Results】Compared with the no NO addition control, the application of 100, 200, and 400 nL/L exogenous NO caused considerable increases by 64%, 42% and 10% respectively in fresh weight and by 88, 61 and 49% respectively in dry weight of pakchoi. The best NO concentration was 100 nL/L. Compared with the control, 100 nL/L, 200 nL/L, and 400 nL/L gaseous NO decreased the nitrate concentrations in pakchoi by 59%, 76%, and 94%, respectively. The NO treatments also induced accumulation of soluble sugar and protein in pakchoi, and the most effective concentration for this effect was 100 nL/L. The exogenous gaseous NO application also significantly elevated the levels of several antioxidant compounds including total phenols, flavonoids, and ascorbate.【Conclusions】Atmospheric application of trace amount of gaseous nitric oxide could be an effective strategy for improving both biomass production and quality of pakchoi. In general, NO 100 nL/L has the best effect on the growth and quality of pakchoi in greenhouse production.