PRODUÇÃO DE MUDAS DE ALFACE EM SISTEMA FLOATING SOB TELA DE SOMBREAMENTO E COBERTURA PLÁSTICA

Abstract

With the objective of evaluating the production of lettuce seedlings in greenhouse under shading and in floating system, it was installed an experiment in the Federal University of Acre, in the period of November of 2006 to January of 2007. The experimental design was in randomized blocks with four replicates, in split-plot arrangement in strips. The strips corresponded to in the greenhouse and field, the strip, in shading (with and without) and constituting the split-plot, the floating system (with and without). The seedlings were cultivated in trays of polystyrene of 128 cells, containing substrate the base of organic composition, charred peel-of-rice and soil in the proportion of 1:1:1, added 10% of the vegetable coal and 1,5 kg m-3 of termphosphate. The screen with 50% of shading was placed to 50 cm of height. After 24 days of the planting, they were appraised the dry masses of the aerial part, of the root and total of the plant. The largest production of dry mass of the plant's aerial and total part was obtained being used it greenhouse and shading screen. Greenhouse, the floating system without shading presented smaller development of the system root and dry mass total, not differing to each other in the shading condition. The production of seedlings without floating system was better with shading in field and without shading in greenhouse. In the general, the best quality of the seedlings was obtained greenhouse.