Níveis de ferro no desenvolvimento de alface crespa em sistema hidropônico NFT

Abstract

Fe is one of the essential micronutrients for the development and reproduction of plants, it participates directly in several cellular processes, such as: respiration, chlorophyll biosynthesis and photosynthesis, and serves as a cofactor for enzymes involved in the transfer of electrons or oxygen. Based on this context, the present study aimed to evaluate the effects of different levels of the micronutrient iron in nutrient solution on the growth and morphology of curly lettuce (cv. Jade) in a hydroponic system. Carried out in a greenhouse at the Federal Institute of Education, Science and Technology of Pará - Campus Castanhal, the experiment used four doses of iron (5g, 10g, 20g and a control of 30g per 1000 liters of nutrient solution), with nine replications, totaling 36 sampling units. After a period of thirty-five days, the variables were collected and measured: fresh mass of the aerial part, fresh mass of the root, plant height, stem diameter, number of leaves, root length, stem height, stem weight and leaf weight. The data were analyzed using SISVAR and the adjustments and validity of the regression equations used to evaluate the experimental results were considered significant at P<0.05. The results indicated that the conventional recommendation of 30g of iron for 1000 liters of solution was not efficient for lettuce cultivation, under the climatic conditions of the study site. It was concluded that the dosage of 15g of iron per 1000 liters of nutrient solution proved to be more appropriate, maintaining satisfactory performance of the analyzed variables, reducing costs with the micronutrient and providing more precise guidelines for the cultivation of curly lettuce in the Amazon region.