CRESCIMENTO INICIAL DE BROTAÇÕES DO ABACAXIZEIRO „PÉROLA‟ A PARTIR DE SECÇOES DE CAULE

Abstract

Considered the third most cultivated fruit tree in the world, the pineapple tree in Brazil faces great difficulties in its diffusion, mainly due to the low phytosanitary quality of the seedlings. The objective of this study was to evaluate the effect of the size of the stem sections and environments on the percentage of sprouts and initial growth of the pineapple tree propagules (Ananas comosus L. var. comosus) cv. Pérola. The experiment was carried out at the Fruticulture Nursery of the Department of Phytotecny and Environmental Sciences of the Center of Agricultural Sciences of the Federal University of Paraiba (DFCA/CCA/UFPB), Areia, PB. The pineapple tree stem “Pérola” were collected, approximately 30 days after the fruits were harvested, in the municipality of Alhandra - PB. After the harvest, the stems were taken to the nursery of the UFPB/CCA where they were sectioned. The experimental design was a completely randomized design, in a 4 x 2 factorial scheme, with lengths of stem sections (5, 10, 15 and 20 cm) and cultivation environments (greenhouse and shade 50% shading), with four replicates, containing 5 sections per experimental unit. The sections of the stems after standardization were placed in beds, containing substrate composed of 60% of organic compound and 40% of carbonized rice husk. After 20 days of the installation of the experiment, the counting of the sprouted buds were evaluated, with an eight-day interval, during eight weeks. At 80 days after planting, growth evaluations were performed: seedling height, rosette diameter, number of leaves, leaf area, fresh and dry shoot mass. There was an increase in the number of sprouts with the increase of the section size being the maximum value 3.2 sprouts found at 57 days after planting in the shade environment. For the height of the seedlings in the shade environment, the section sizes conformed to the linear regression model, with a 32.7% increase from the smallest section size (5 cm) to the largest size (20 cm), in the greenhouse environment, the sections presented a quadratic behavior with an estimated minimum point of curvature of 6.90 cm in the section of 8.34 cm. The section of 20 cm is indicated to obtain pineapple tree seedlings 'Pérola' by stem sectioning. The greenhouse environment provides the best growth of pineapple tree seedlings “Pérola”.