This work was carried out at the Mato Grosso State University, Tangará da Serra campus, Brazil, aiming to evaluate the agronomic characteristics of crisphead lettuce cultivars depending on filter cake rates application in protected environment. We used a randomized blocks design in a 3x4 factorial scheme, composed by three cultivars (Júlia, Tainá and Rafaela) and four rates (0, 10, 20 and 40 t ha-1), with four replications. Plots size was 1.2x1.2 m with 16 plants spaced 30x30 cm each, among which the 4 central plants were evaluated. We assessed the total fresh mass, marketable fresh mass, head fresh mass, total leaf number, marketable leaf number, stem length, stem diameter and plant diameter. The cultivar Rafaela presented the highest performance for fresh mass total, marketable and head, at the filter cake rate of 20 t ha-1. The cultivars Júlia and Rafaela had greater plant diameter, stem diameter, total leaf number and marketable leaf number than cultivar Tainá, regardless the filter cake rate applied. The filter cake application provided higher yield and marketable quality for crisphead lettuce.
Lactuca sativa; organic residue; organic fertilizer; cultivars
