Controlled-Release Fertiliser and Substrates on Seedling Growth and Quality in Agonandra brasiliensis in Roraima

Abstract

The aim of this study was to verify the effect of different substrates, in the presence and absence of controlled-release fertiliser, on the growth and morphological quality of seedlings of Agonandra brasiliensis Miers ex Benth. & Hook.f., in the state of Roraima, Brazil. The experimental design was a 2 * 5 factorial scheme, with and without the addition of 1.0 g L^-1 NPK 18-05-09 formulation controlled-release encapsulated fertiliser (Forth Cote^R) and five substrates. The following were evaluated: shoot height (H), collar diameter (CD), increase in shoot length (IncH) and collar diameter (IncCD), shoot dry weight (SDW), root dry weight (RDW), total dry weight (TDW) and Dickson quality index (DQI). The use of NPK 18-05-09 formulation controlled-release fertiliser (Forth Cote^R) in a medium-sand substrate is recommended for obtaining plants of Agonandra brasiliensis of greater robustness, balance of biomass distribution, and a high standard of quality. In the substrate composed of soil from the cerrado + carbonised rice husks - CRH + organic substrate (2:1:1), the addition of NPK 18-05-09 formulation Forth Cote^R is not necessary to obtain Agonandra brasiliensis plants of good morphological quality. Substrate 3, composed of soil + CRH (3:1), with or without the addition of NPK 18-05-09 formulation Forth Cote^R, is not recommended for producing plants of Agonandra brasiliensis, due to the slow development and reduced morphological quality of the plants.