Produção e qualidade de mudas de mogno africano cultivadas com solução nutritiva

Abstract

The objective of this study was to determinate the quality pattern of seedlings by morphologic parametres of height/diameter ratio, production of dry content of leaves, stem and roots, Dickson Quality Index (DQI), as well, determinate macronutrients and micronutrients content in African Mahogany Khaya ivorensis and Khaya senegalensis. Thirty days after the emergence, the seedlings with 7 cm height, were transplanted to plastic vases of 14 L (two seedlings/vase). In each vase were put a small layer of pebble, to facilitate the drainage, and completed with organic substratum (Organoamazon®). Every week, plants were irrigated once with nutrient solution ((0,8 g/L (Maxsol), 0,5 g/L (Calcium nitrate) e 0,1 g/L (iron)) and, on the last two weeks of the third month, the irrigation were twice per week. From fourth to fifth month the concentration of nutrient solution was increased to 1,2 g/L (Maxsol), 0,9 g/L (Calcium nitrate) e 0,1g/L (iron). And in the sixth month the solution concentration was 1,3 g/L (Maxsol), 1,0 g/L (Calcium nitrate) e 0,1 g/L (iron). Height and diameter were analyzed in completely randomized design in split plots, with two species (K. ivorensis e K. senegalensis) and two treatments (with and without the nutrient solution) in the plots and eleven periods in the sub-plots. The seedling quality was analyzed by morphologic index: height/diameter ratio, dry material production of leaves, stalk and roots, Dickson quality index (DQI). African Mahogany plants (K. ivorensis e K. senegalensis) show fast and vigorous vegetative growth, K. senegalensis grow 24 cm height and 7 mm of diameter in 60 days after the transplant and K. ivorensis 28 cm and 5,5 mm of height and diameter respectively, 90 days after de transplant. K. senegalensis with nutrient solution addition show superior growth and dry material production. To both species, with and without nutrient solution there is no difference in the contents of micro and macro nutrients absorbed.