Abstract:

In order to explore the effects of polyaspartic acid-magnesium (PASP-Mg) on the production of spinach, this study used large-leaf spinach as the experimental material and systematically analyzed the impacts of different application rates (1.50, 2.25, 3.00 kg·hm^-2) of PASP-Mg on its growth, yield, quality, and nutrients accumulation. The results indicated that within the tested application rates, PASP-Mg did not exhibit any inhibitory effects on spinach growth. All treatments with PASP-Mg demonstrated significant (p<0.05) yield-increases by 10.20%-11.10%. In terms of quality, the application of PASP-Mg significantly reduced nitrate content in spinach by 9.28%-13.11%, while significantly increased chlorophyll, vitamin C, and soluable protein content by 19.57%-23.91%, 12.32%-17.90%, 14.34%-22.13%, respectively. In terms of nutrients accumulation, the contents of nitrogen, phosphorus, and potassium were significantly increased by 8.29%-10.35%, 9.53%-18.75% and 8.58%-9.36%, respectively, with PASP-Mg application. Based on the comprehensive analysis of spinach quality and yield and application cost, the optimal application rate of PASP-Mg under the experiment conditions was 2.25 kg·hm^-2, which could achieve the goals of increasing yield and improving quality.

Key words: polyaspartic acid-magnesium (PASP-Mg), application rate, spinach