RESULTS CONCERNING OBTAINING OF LETTUCE ON PERLITE SUBSTRATE

Some results regarding the obtaining of lettuce (Lactuca sativa) on perlite substrate are in this study. Lettuce is a popular vegetable in Romania. Among the aims of lettuce culture are yield and quality. Lettuce culture results depend on the quality of the seedlings. The experience of this paper aimed at identifying of a technological sequence for obtaining of lettuce in unconventional system, on perlite substrate. The research has been carried out in the Hortinvest greenhouses, within the Research Center for the Quality of Horticultural Products at the University of Agronomic Sciences and Veterinary Medicine of Bucharest, in (October–November) 2016 and (March–April) 2017 years, on a variety of lettuce („Alanis” from the Seminis company). Perlite (2 mm and 4 mm) has been the unconventional substrate used in the lettuce production. Fertilization has been done in several variants: chemical and with different products (Formulex, Iguana and Vermiplant). The lettuce seedling variant obtained on perlite with a 4 mm grain size and treated with Vermiplant has had the best average result (3.65 leaves). The variant of lettuce grown on a 4 mm granulated perlite mattress and treated with Vermiplant has had the best result after 25 days from planting (22.55 leaves). The unconventional soilless lettuce culture system, on perlite substrate, has optimal results and it is also recommended in Romania.