Container volume and doses of maximum technical efficiency of controlled-release fertilizer on the morphological quality of Cordia alliodora seedlings in Roraima

The objective of this study was to determine the correlation between the morphological characteristics of Cordia alliodora seedlings produced as a function of container volume and controlled-release fertilizer (CRF) doses under nursery conditions in Northern Amazon. The experimental design was a 2 x 6 factorial scheme, corresponding to two container volumes (1.8 and 2.2 L) and six doses of Forth Cote® (0, 1, 2, 4, 8, and 12 g L-1 in medium sand), with five replicates. The evaluations were: height (H), stem diameter (SD), shoot dry mass (SDM), root dry mass (RDM), total dry mass, increment in stem diameter (ΔSD) and increment in height (ΔH) obtained from the data collected every fifteen days, from transplanting, encompassing the period of plant growth until the end of the experiment (three months), in addition to Dickson quality index (DQI). Container volume of 2.2 L is suitable for the formation of good-quality Cordia alliodora seedlings at 90 days after transplanting. Controlled-release fertilizer doses from 8.0 g L-1 are not indicated to obtain seedlings of this species in the northern region of Brazil, with quality, regardless of the container volume.