Lettuce yield in growing environments using seedlings produced with increasing volume of substrate

Abstract

The search for technologies for the organic cultivation of lettuce is necessary to increase production. Thus, this work aimed to evaluate the productivity of crisp lettuce cv. Vera, in cultivation environments, with seedlings produced with increasing volumes of substrate. The experiment was carried out at Sítio Ecológico Seridó, Rio Branco, AC. Installed in two cultivation environments: covered greenhouse and closed sides and greenhouse only covered with additive film. The design used was in completely randomized blocks, with five volumes of containers: 70 cm3, 160 cm3, 250 cm³, 340 cm³ and 430 cm³, with four replications for each cultivation environment. The harvest was carried out 55 days after sowing and evaluated: total and commercial fresh weight and total and commercial productivity. The greenhouse with open sides showed better performance in all of the analyzed variables. Greater total fresh weight was obtained for the 400 cm³ container (229.956 g plant^-1) and commercial fresh weight was 360 cm³ (174.073 g plant^-1). Thus, lettuce is cultivated in a greenhouse with open sides. And higher commercial productivity (13.8 t ha^-1) is obtained with seedlings produced with volume of 370 cm³ of substrate.