Nitrogen Source and Rate Influence on Growth and Physiology of Cinchona micrantha Seedlings

Fernandez-Zarate F.H.; Diaz L.; Sanchez J.; Quispe-Carhuapoma M.J.; Coronel-Bustamante D.; Perez-Delgado L.; Chavez-Collantes A.; Taboada-Mitma V.H.; Cruz-Luis J.; Seminario-Cunya A.; Huaccha-Castillo A.E. · International Journal of Design and Nature and Ecodynamics (2026) · DOI: 10.18280/ijdne.210103

Resumen

Cinchona micrantha, an Andean species with high medicinal value due to its alkaloids such as quinine, faces propagation difficulties due to a lack of knowledge about its initial nutritional requirements. This study evaluated the differential effect of nitrogen (N) sources and levels on the morpho-physiological development of Cinchona micrantha under nursery conditions. Twelve treatments resulting from the combination of three sources of nitrogen fertilization (conventional urea, urea + N-(n-butyl)thiophosphoric triamide (NBPT), and urea + 3,4-dimethylpyrazole phosphate (DMPP)) and four dose levels (0, 0.3, 0.6, and 0.9 g/plant) were analyzed using a completely randomized factorial design. Growth parameters (height, stem diameter, biomass, leaf area), relative chlorophyll content (SPAD), and survival were measured every two weeks for four months, as well as physicochemical changes in the soil at the beginning and end of the trial. The T22 treatment (urea + NBPT, 0.6 g/plant) showed the best performance, with increases of 67% in height, 20% in diameter, 61% in leaf area, 2.5-fold in above-ground biomass, and 2.4-fold in root biomass, as well as 13% more chlorophyll, maintaining low mortality and no phytotoxicity. In contrast, higher doses (0.9 g/plant) generated abiotic stress and high mortality (> 80% in T31 and T33). This study provides scientific evidence applicable to the design of balanced fertilization schemes in nurseries, with direct implications for reforestation programs, ecological restoration, and conservation of medicinal species native to the Andes.

Instituciones: Universidad Nacional Autónoma de Chota; Universidad Nacional de Jaén