硫酸根硫和单质硫对青菜硫素营养的影响

为探究施用硫酸根硫(SO42--S)和单质硫(S⁰-S)对土壤有效硫含量及青菜硫素营养的影响,以矮脚黄青菜品种为材料,采用小区试验,分析不同类型硫肥(硫酸钾和硫磺粉)处理对供试土壤pH值、土壤有效硫含量、青菜产量及硫素营养含量的影响。结果表明,施用硫酸钾(SO42--S)和硫磺粉(S⁰-S)均降低了弱碱性土壤pH值,增加了土壤有效硫含量,且施用SO42--S的影响较S⁰-S更明显。施用SO42--S和S⁰-S均可有效提高青菜株高、可食部分干重和含硫量,均在106 g·m^-2处理水平下达到最大值,且施用SO42--S的提升作用优于S⁰-S。53 g·m^-2SO42--S处理水平下,与对照相比,青菜可食部分硝酸盐含量下降了38.6%,可溶性蛋白、可溶性糖和维生素C含量分别增加了115.1%、120.5%和21.7%。综上,适度施用SO42--S肥料有利于改善弱碱性缺硫土壤物理化学性质,提高青菜产量和营养品质。本研究结果为缺硫地区青菜优质优产种植提供了科学依据。

Effects of SO42--S and S0-S on the Sultur Nutrition in Pakchoi

To investigate effects of different forms of sulfur on the content of available sulfur in soil and quality characters in edible pakchoi, a plot experiment was conducted to evaluate the parameters such as soil pH, available sulfur in soil, biomass and nutritional quality in edible parts of pakchoi. The results showed that application of potassium sulfate (SO42--S) and sulfur powder (S⁰-S) reduced pH of weakly-alkaline soils and increased soil available sulfur content, and the decrease of application of SO42--S was more obvious than that of application S⁰-S. Application of sulfur fertilizers can effectively increase plant height, dry mass and sulfur contents in edible parts of pakchoi. Both kinds of sulfur fertilizers reached its maximun effect at the level of 106 g·m^-2for enhancing plant height, dry weight and sulphur content in edible parts of pakchoi, and the increase of application of SO42--S was more significant than that of S⁰-S. Compared with CK, the soluble protein, soluble sugar, and vitamin C contents in the edible parts of pakchoi increased by 115.1%, 120.5%, and 21.7%, respectively, whereas nitrate content in the edible parts of pakchoi decreased by 38.6% at the treatment of SO42--S2 (53 g·m^-2). In conclusion, the application of SO42--S2 (53 g·m^-2) improves the physical and chemical properties of weak-alkaline and sulfur-deficient soil, and enhance yield and quality of pakchoi. The results of this study provide a scientific basis for the cultivation of high yield and high quality of pakchoi in the sulfur-deficient area.