DESEMPENHO DE CULTIVARES DE ALFACE AMERICANA EM AMBIENTES SOMBREADOS NA REGIÃO DO SUBMÉDIO SÃO FRANCISCO-BA

Abstract

The lettuce is a leafy vegetable and when it is cultivated in regions of intense solar radiation it can¿t develop it's full genetic potential. In this direction this work had the objective of evaluating the productivity of the Butterhead lettuce cultivar using different types of screens in the region of the Submédio São Francisco. The experiment was carried out in raised planting beds, using black screens with 30 and 50% of shading, white screens and in the open sun. The statistical design was the factorial 2x4 and the means were compared by the Turkey test at 5% of probability. In each treatment a termohigrometre and temometers at 40 cm from the ground were coupled with a black globe to get the radiant thermal load, the temperature of the air and the humidity index. At the end of the trial chlorophyll, the diameter of the head, plant height, the number of leaves per plant, the leaf area, fresh and dry weight of plants were collected. The screens affected the parameters analyzed and the treatment PS and TB of shading were the best for commercial parameters.