Comparative Study of the Leachates from Syngonium podophyllum using Different Fertilization Techniques and Nitrogen Forms

Abstract

The objectives of this article were to analyze the evolution of the nutrient parameters of the leachates collected from Syngonium podophyllum var. Silver plants cultivated for 20 weeks in a buried greenhouse with four methods of fertilization. The treatments were T1, standard liquid feeding (SLF) [7.0 mmol L−1 nitrate (NO3 −) nitrogen (N), 0.3 mmol L−1 phosphorus (P), and 3.5 mmol L−1 potassium (K)] after transplanting; T2, liquid feeding soluble fertilizer (LFSF) [6.9% NO3 − N, 11.1% ammonium (NH4 +) N stabilized by 3,4-dimethylpyrazole phosphate, 8.0% P2O5, and 14.0% K2O] after transplanting; T3, controlled release fertilizer (CRF I) (7.4% NO3 − N, 8.6% NH4 + N, 8.0% P2O5, and 12.0% K2O) applied before planting and half concentration of SLF from 45 days after transplanting; and T4, controlled release fertilizer (CRF II) (8.5% NO3 − N, 7.5% NH4 + N, 8.0% P2O5, and 12.0% K2O) applied before planting and half concentration of SLF from 45 days after transplanting. Solution pH, electrical conductivity (EC), NO3 − N, NH4 + N, K, and P concentrations in the leachate were analyzed weekly. Plant quality was assessed at the end of the trial through objective and subjective parameters. Significant differences among the different fertilization methods were observed. CRF treatments resulted in the greatest nutrient leachate concentration during the first 6 weeks of the study, and afterward it decreased gradually until the end of the cultivation. CRF I showed greater leachate concentrations of N, P, and K than the others during the first half of the study. The concentrations of NO3 − N and P from all the fertilizer types were often above the permissible levels cited in the federal Clean Water Act. The best-quality plants were obtained with CRF II, whereas the greatest height and Aerial Dry Weight (ADW) were obtained with CRF treatments and the greatest Root Dry Weight (RDW) was obtained with the NH4 + N treatments.