外源钙对小白菜酶活性、钙含量及其产量和品质的影响

Effects of exogenous CaCl2 on the enzyme activity,leaf calcium concentrations,yield and quality of cabbage

为研究不同时期喷施不同浓度的外源钙对小白菜酶活性、钙含量及其产量和品质的变化规律,明确小白菜富集钙的最佳喷施量和最佳施用期,以苏州青、兔耳白、上海青为试验材料,采用田间试验,设置6个供钙水平[清水对照(T_0)、50 mg/L CaCl_2(T_1)、100 mg/L CaCl_2(T_2)、150 mg/L CaCl_2(T_3)、200 mg/L CaCl_2(T_4),250 mg/L CaCl_2(T_5)],在移栽7、14、21 d叶面喷施,研究不同时期喷施不同浓度钙对小白菜酶活性、钙含量及其产量和品质的影响。结果表明:不同时期喷施不同浓度外源钙处理的小白菜,不同品种间过氧化氢酶(CAT)和过氧化物酶(POD)表现出显著差异水平,并且随着喷施钙浓度的增加,两种酶活性均呈现先升高后降低的趋势,在T3处理中酶活性达最大,移栽后14 d CAT和POD活性分别比对照增加79.33%和114.05%。随着钙浓度的增加,不同喷施时期、不同小白菜品种钙含量均表现出显著增加,且移栽14 d喷钙对叶片的钙含量影响最大,移栽7 d影响最小。不同品种同一时期钙含量为上海青>苏州青>兔耳白。叶面喷施钙可以提高小白菜Vc、可溶性糖、游离氨基酸含量,降低叶片硝酸盐的含量,不同喷施时期不同品种小白菜Vc、可溶性糖、游离氨基酸含量与对照相比均表现为T_3处理增加最显著,最高增加了10.91%、3.94%和10.82%。移栽后21 d兔耳白在钙处理T_3时硝酸盐含量达到最低,比对照降低9.09%。喷施不同浓度钙,显著提高小白菜钙含量,且随着钙浓度的增加表现出先增加后减少的趋势,T_3处理时达到最大。移栽21 d,T_3处理上海青、兔耳白、苏州青产量与对照相比分别增加4.86%、3.09%和3.83%。因此,适量喷施外源钙可提高小白菜叶片酶活性,改善品质,增加产量。移栽21 d喷施150 mg/L CaCl_2为小白菜叶面喷施钙的最佳施用期和最佳施用量。

To explore the effect of different concentration of calcium on yield,quality,enzyme activity and leaf calcium content of pakchoi in different growth stages,and to determine the optimal application amount and period of exogenous calcium in pakchoi,using Suzhou Green,Rabbit Ear White and Shanghai Green as experimental materials,six calcium supply levels[water control(T0),50 mg/L CaCl2(T1),100 mg/L CaCl2(T2),150 mg/L CaCl2(T3),200 mg/L CaCl2(T4),250 mg/L CaCl2(T5)]were sprayed on the leaves of pakchoi at 7,14 and 21 days after transplanting in the field test.The effects of different concentrations of calcium on enzyme activity,calcium content,yield and quality of pakchoi were studied.The results showed that there were significant differences in catalase(CAT)and peroxidase(POD)among different varieties of pakchoi treated with different concentrations of exogenous calcium in different periods,the activities of the two enzymes both increased first and then decreased with the increase of the spraying calcium concentration,and the enzyme activity reached the maximum in the T3 treatment,and the CAT and POD activities increased by 79.33%and 114.05%,respectively,compared with the control in 14 days after transplanting.With the increase of calcium concentration,the content of calcium increased significantly in different spraying periods and varieties of pakchoi,and spraying calcium on the 14th day of transplanting had the greatest impact on the calcium content of the leaves,and the impact on the 7th day after transplanting was the least.At the same time,different varieties showed Shanghai Green>Suzhou Green>Rabbit Ear White.The content of VC,soluble sugar,free amino acid in leaves of pakchoi could be increased by spraying calcium on the surface of leaves and nitrate decreased.Compared with the control,the content of VC,soluble sugar and free amino acid in different varieties of pakchoi in different spraying periods increased the most in T3 treatment,with the highest increase of 10.91%,3.94%and 10.82%.After 21 days of transplantation,the content of nitrate in T3 of Rabbit Ear White treated with calcium was the lowest,which was 9.09%lower than that of the control.Spraying different concentrations of calcium significantly increased the calcium content of pakchoi,and with the increase of calcium concentration showed a trend of increasing first and then decreasing,T3 treatment was the maximum.After 21 days of transplanting,the yield of Shanghai Green,Rabbit Ear White and Suzhou Green increased by 4.86%,3.09%and 3.83%,respectively.Appropriate application of exogenous calcium can improve the enzyme activity,quality and yield of pakchoi leaves.Spraying 150 mg/L CaCl2 after 21 days transplanting was the best application period and dosage for spraying calcium on the leaves of pakchoi.