CONTROLLED RELEASE FERTILIZER AND TUBE VOLUME IN THE PRODUCTION OF AFRICAN MAHOGANY SEEDLINGS

Abstract

Background: The present study verified the effect of controlled-release fertilizer (CRF) doses combined with tube volumes on the initial growth of seedlings of Khaya anthotheca and Khaya grandifoliola, through evaluations of morphological, physiological, and nutritional characteristics. The experiment was conducted in a factorial arrangement (5 × 2), evaluating the interaction of five concentrations of 15-9-12 CRF and two tube volumes. After 180 days, the morphological parameters of the seedlings were evaluated. Samples of the aboveground and root parts were collected for determination of macronutrients and organic carbon.

Results: Regarding the interaction dose × container volume, for all evaluated characteristics, K. anthotheca and K. grandifoliola seedlings grown in substrate without the addition of CRF showed the lowest means, while seedlings with higher doses resulted in statistically superior responses for the studied attributes. The multivariate analysis of principal components, concerning the nutrients present in the leaves and roots of K. anthotheca and K. grandifoliola, allowed for characterizing the groups of nutritional similarities between the CRF doses and the volume of the tubes.

Conclusion: The different doses of CRF resulted in significant variations in the growth of K. anthotheca and K. grandifoliola seedlings, with the application of the 10 g L-1 dose of CRF recommended for both species. The volume of the tubes did not show disparities in the morphological growth characteristics analyzed in the studied species, highlighting the Dickson Quality Index as one of the most accurate measures. The volume of 280 cm³ stood out, indicating seedlings of better quality.