Evaluation of phenolic foam treatments for lettuce seedling production

Abstract

Phenolic foam is a substrate highly used in seedlings preparation for hydroponics cultivation. This work was carried out in two assays, aiming at evaluating phenolic foam pre-treatment in lettuce seedlings production. The first assay consisted of the following pre-treatments: no washing, washing with tap water and washing with NaOH or KOH 0.1 N; 0.05 N; 0.01 N. The second assay consisted of phenolic foam washing in NaOH 0.1 N, in the proportion 15, 30, 60, 90 and 120 cells per solution liter. Lettuce seeds, of the cultivar “Verdinha de Vitoria”, were sown in previously treated phenolic foam, daily irrigated with tap water for five days, followed by nutritive solution irrigation. In the first assay, germination rate 15 days after seeding in unwashed phenolic foam was 23.04%, which is statistically different from the other treatments that did not differ and presented germination averages of 74.69%. In the second assay, it was observed that there is no significant difference among phenolic foam washing in the proportion 15, 30, 60, 90 or 120
cells per NaOH solution liter (0.1 N).