Cultivares de alface crespa em cultivo hidropônico em Manaus, AM

Abstract

Lettuce (Lactuca sativa L.) is a leafy vegetable, which has great commercial importance. Currently, it is one of the most popular and consumed vegetables in the world. Achieving successful harvesting is linked to several factors, including the correct choice of cultivar. However, the climatic conditions of the Amazon region, such as heavy rains and high temperatures in certain months of the year, have caused tornadoes to require the cultivation of some vegetables, such as lettuce, which particularly require specific conditions for their development. Given the scarcity of information on the adaptation of curly lettuce cultivars in a hydroponic system, in the climatic conditions of Manaus, AM, this work aims to evaluate the agronomic performance of eight curly lettuce cultivars in a hydroponic system in the dry season, in the months of May to July (first cultivation period) and from August to September (second cultivation period) of 2023. The experimental design used was randomized blocks, in an 8 factorial scheme (eight cultivars: BRS Leila, BS AC0055, BS AC0063, Caipira, Jade, Jonction RZ, Psiquê and Vera) x 2 (two cultivation periods), with four replications. The plots were composed of nine plants, grown in an NFT (Nutrient Film Technique) hydroponic system. The plants were harvested 45 days after sowing, and the following response variables were evaluated: plant height; number of leaves per plant; stem length; fresh aerial part mass; fresh leaf mass; fresh stem mass and dry stem mass. The data were subjected to analysis of variance (F test), with the means compared using the Tukey test, at a 5% probability level. The cultivar BS AC0055 showed signs of early bolting, due to the greater plant height and longer stem length. The BRS Leila cultivar presented high values for plant height, number of leaves, fresh mass of the shoot and stem, and dry mass of the stem. Comparing important variables for marketing, the Jade and Caipira cultivars also stood out. The other cultivars Jonction RZ, Psiquê and BS AC0063 demonstrated, in general, intermediate performance under environmental and management conditions.