Location: Soil Dynamics ResearchTitle: Initial growth of Araucaria angustifolia (Bertol.) Kuntze in response to fertilization with nitrogen, phosphorus and potassium
|CONSTANTINO, VALDECI - Universidade Federal Do Parana|
|BARBOSA, JULIERME - Universidade Federal Do Parana|
|MOTTA, ANTONIO - Universidade Federal Do Parana|
|DOLINSKI, MARCOS - Universidade Tuiti Do Parana|
|Prior, Stephen - Steve|
|ZANETTE, FLAVIO - Universidade Federal Do Parana|
Submitted to: Floresta
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/3/2018
Publication Date: 12/17/2018
Citation: Constantino, V., Barbosa, J.Z., Motta, A.C., Dolinski, M.A., Prior, S.A., Zanette, F. 2018. Initial growth of Araucaria angustifolia (Bertol.) Kuntze in response to fertilization with nitrogen, phosphorus and potassium. Floresta. 49(1):99-108. https://doi.org/10.5380/rf.v49i1.57467.
Interpretive Summary: Araucaria angustifolia, commonly known as araucaria, Paraná pine, or Brazilian pine is an endangered species due to over exploitation and slow growth. Due to lack of information on basic nutritional requirements of araucaria seedlings, this work evaluated how N, P, and K fertilization affected seedling growth. Increased seedling quality was only observed with N and P fertilization, but not with K fertilization. Findings suggest that nursery applications of N and P are required for improved rootstock growth and quality that will enhance reforestation efforts of this endangered species.
Technical Abstract: Reforestation of Araucaria angustifolia (Bertol.) Kuntze, an endangered species native to South America, has been proven difficult due to slow initial growth. Fertilization should enhance araucaria seedling growth, but there is a lack of information regarding basic nutritional requirements. Three experiments were conducted to assess the growth response of A. angustifolia rootstock to N, P and K applications. Five rates of N, P, and K were tested individually. Phosphorus and K were applied once by mixing with soil before transplanting seedlings, and N was split into three summer applications. Seedlings were transplanted into pots containing 16 dm3 of soil, and the response to nutrient applications was monitored by measuring plant height and base diameter for 21 months. At harvest, seedling dry mass (roots, needles, branches, and stem), seedling quality index, and nutritional deficiency symptoms were evaluated. Chlorophyll relative index (CRI) and needle color were also measured in the N experiment. Increased plant quality was only observed with N (up to 1238 mg dm-3) and P fertilization (up to 472 mg dm-3). Chlorotic needles, small needle size, and premature death of lower branches were the main symptoms of N deficiency while dark green needle coloration, sparse secondary branches, and short internodes characterized P deficiency. Findings suggest that nursery applications of N and P are required for improved rootstock growth and quality.