Comparison of two pressurized irrigation systems on lettuce seedlings production

摘要

Automatized irrigation systems under nursery conditions have become an essential tool to satisfy rationally the water needs for plants without forgetting the sustainability aspects. The present study aimed to evaluate two sprinkler irrigation systems under nursery conditions: one with fixed laterals (fixed system) and another with self-propelled laterals (mobile system) and study the effect of their use on the behavior of tree lettuce seedlings production. The experiment was conducted on a greenhouse with a polystyrene (PVC) plastic film coverture and laterals closed with 60% plastic screen. The statistical design used was a 2x3 completely randomized factorial with four replicates, and the results analyzed using the Tukey test. To compare the lettuce seedlings behavior under both irrigation systems it was evaluated the leaves number, seedling’s height, root length and fresh and dry mass of the aerial and root part of the plant. The Christiansen uniformity coefficient (CUC) and the water distribution coefficient (WDC) for the fixed irrigation system were considered adequate and for the self-propelled laterals system (mobile system) they were considered excellent. The volume of water used with the fixed system was 109.12% higher than with the self-propelled system. The lettuce seedlings irrigated with the self-propelled system had a growth, production and a seedling quality statistically superior than when irrigated with the fixed system. Independent of the irrigation system used, the Elizabeth lettuce cultivar had a greater seedling behavior. According with the results obtained, it is recommended the use of the self-propelled irrigation system (mobile system) on the production of lettuce seedlings.