水杨酸和亚硫酸氢钠降低小白菜硝酸盐累积的复合效应研究

The Compound Effect of SA and Sodium Bisulfite on Reducing Nitrate Accumulation in the Leaf of Non-heading Chinese Cabbage

以"佳惠"青梗小白菜为试材,针对叶菜类蔬菜硝酸盐(NO3-)累积影响农产品安全质量问题,以调控氮代谢促进硝酸盐还原同化为切入点,研究了水杨酸(SA)和亚硫酸氢钠(NaHSO3)叶面喷施对小白菜叶片硝酸盐累积的下调效应及营养品质的影响。结果表明:叶面喷施3mmol/L SA和10mmol/L NaHSO3处理后第12天可以显著降低小白菜叶片NO3-含量,分别降低了39.71%、35.91%;而2mmol/L SA和8mmol/L NaHSO3复合叶面喷施在处理后第12天小白菜叶片NO3-含量显著降低了56.35%,呈现出明显的复合效应;同时,二者复合处理可以显著提高小白菜的鲜重、干重和干重/鲜重,而对小白菜株高作用无显著影响;而氮代谢关键酶,硝酸还原酶(NR)、谷氨酰胺合成酶(GS)、谷氨酸草酰乙酸转氨酶(GOT)、谷氨酸丙酮酸转氨酶(GPT)活性分别提高了43.65%、40.83%、32.37%、80.21%;另外,小白菜叶片可溶性糖、可溶性蛋白质、游离氨基酸和维生素C含量也分别增加了32.47%、24.55%、30.50%、55.56%。

Taking non-heading Chinese cabbage ＇Jiahui＇ as material .aimed at resolving the problem of nitrate accumulated in the leaf vegetables influencing the quality of agricultural products badly, basing itself on the nitrogen and sulfur metabolism correlation, the effect of different ratios of salicylic acid （SA） and sodium bisulfite （NaHS03） on the nutritional quality and nitrate content in the leaf of non-heading Chinese cabbage were studied. The results showed that, on the 12th day, when spraying 3 mmol/L SA or 10 mmol/L NaHS03 .they could reduce the nitrate content in the leaves of non-heading Chinese cabbage for 39. 71 % or 35. 91 % ,but when the ratios of SA was 2 mmol/L and the NaHS03 was 8 mmol/L,the mixture brought the best effect, reducing the nitrate content to 56. 35%, showed an obvious combined effect. At the same time , the fresh weight ,dry weight and fresh weight/dry ＇weight were significantly improved except the height;however the activity of key enzymes of nitrogen metabolism such as NR,GS,GOT and GPT were increased by 43. 65 % ,40. 83 % ,32. 37 % and 80. 21 % respectively. In addition, the soluble sugar, the soluble protein, the amino acids and the vitamin C content were increased 32.47% ,24.55% ,30.50% and 55. 56% respectively.