Effects of sugar alcohols and amino acids on growth, quality and calcium nutrition of Chinese cabbage

【Objectives】 Researches of low molecular organic compounds applying in agriculture are mostly on their nutritional function for crops, such as promoting the growth, improving the quality and so on. But, researches of low molecule organic compounds effecting on nutrient availability, absorption and utilization for plants, especially on absorption and utilization of trace elements are few. In this article, we have studied the effects of low molecule organic compounds, such as sugar alcohols and amino acids, on the Chinese cabbage growth, quality, nutrient absorption and utilization and the calcium availability. 【Methods】 A pot experiment was conducted and the plant was Chinese cabbage. Ten trial treatments were arranged with six replicates, water sprayed as a control, amino acids (Glycine and Glutamate), sugar alcohols (Mannitol and Xylitol) and calcium nitrate sprayed separately, and amino acids (Glycine and Glutamate) and sugar alcohols (Mannitol and Xylitoled) sprayed with calcium nitrate. The concentrations of amino acids, sugar alcohols and calcium ion for the spraying were 250 mg/L, 150 mg/L and 130 mg/L, respectively. We measured the biomass, the contents of vitamin C, soluble sugar, nitrate and soluble protein of Chinese cabbage after the harvest, and analyzed the accumulation of nitrogen, phosphorus, potassium and calcium in plants. 【Results】 1) The foliar application of sugar alcohols and amino acids significantly increases the growth and nutrient uptake, and improves quality of Chinese cabbage. Compared with the spraying water (CK),the spraying of sugar alcohols and amino acids increases the biomass by an average of 9.17%, the contents of vitamin C, soluble sugar and soluble protein are increased by the averages of 20.96%, 50.78% and 30.66% respectively, the content of nitrate is reduced by an average of 31.07%, the accumulation amounts of nitrogen, phosphorus and potassium are increased by the averages of 12.43%, 15.24% and 42.16% respectively, and the accumulation of calcium is increased significantly by an average of 25.65%. 2) The sugar alcohols or amino acids sprayed with calcium nitrate respectively could effectively promote the absorption of calcium, and improve the effects of calcium nitrate applying on Chinese cabbage. Compared with the spraying calcium nitrate, the sugar alcohols and amino acids sprayed with calcium nitrate could increase the biomass of Chinese cabbage by an average of 17.44%, enhance the contents of vitamin C, soluble sugar and soluble protein by the averages of 14.23%, 45.27% and 33.43% respectively, promote the accumulation amounts of nitrogen, phosphorus and potassium by the averages of 38.25%, 16.13% and 25.11% respectively, and improve the accumulation of total calcium by an average of 27.75%; compared with the spraying low molecular organic compounds, the sugar alcohols and amino acids sprayed with calcium nitrate could increase the biomass of Chinese cabbage by an average of 12.04%, and improve the accumulation of total calcium by an average of 17.60%. 【Conclusions】The foliar application of sugar alcohols and amino acids can effectively increase the biomass, the quality and the nutrient absorption of Chinese cabbage. The sugar alcohols and amino acids sprayed with calcium nitrate could significantly increase the calcium uptake, and improve the effects of the calcium fertilizer applying on Chinese cabbage. Therefore, low molecule organic compounds as sugar alcohols and amino acids can be used as effective additives in calcium fertilizer to promote the uptake and utilization of calcium, improve the availability of calcium and enhance the effects of calcium fertilizer applying in agriculture.