Crescimento e fisiologia de mudas de mamão (Carica papaya L.) cultivadas em diferentes substratos.

Abstract

Among the fruits widely cultivated and commercialized in Brazil and in the world, we can mention as a highlight the papaya (Carica papaya L.), because it has high economic value and good financial return. We know that the production stage of seedlings is of great importance, since it is a fundamental step to obtain the uniformity of the plants. Many studies report that the type of substrate, the growing environment and the correct management are essential factors for the full development of the seedlings. In view of the above, the present work had as objective to evaluate the development of seedlings of papaya cultivar Sunrise Solo cultivated in different organic substrates. The experiment was conducted in a greenhouse of the Department of Phytotechnology, at the Pici Campus, belonging to the Federal University of Ceará. The experimental design was a completely randomized design consisting of 4 substrates (commercial Turfa Fértil, bagna de carnaúba, crushed green coconut fiber and sewage sludge) with 5 replicates, each replicate being composed of 6 papaya seedlings, totaling 120 experimental units. In relation to the results, significant increases were observed for the variables plant height, stem diameter, leaf number, leaf area, root length and total dry mass, when the substrates were used with bagna of carnauba and green coconut fiber 68.98%, 61.85%, 57.46%, 96.54%, 71.36%, 86.04%, respectively. Regarding the physiological variables, there were increases of 43.61% for photosynthesis and 34.75% for water use efficiency. From the results, we can conclude that the substrates with carnauba bagana and crushed green coconut fiber were the most efficient for the production of seedlings of papaya cultivar Sunrise Solo, all biometric aspects being increased, but the physiological aspects were little influenced by the themselves.