Substrate with Organosuper® for cucumber seedlings formation in protected environments and polystyrene trays Substrato com Organosuper® para formação de mudas de pepineiro em ambientes protegidos e bandejas de poliestireno

Culture environments, trays and doses of organic compost were evaluated in the formation of cucumber seedlings (Cucumis sativus L.). Five environmental conditions were tested: (A1) a greenhouse with height of 2.5 m, covered with polyethylene film, (A2) nursery with height of 2.5 m, monofilament fabric, 50% shading, (A3) nursery with height of 2.5 m, heat-reflective screen, 50% shading, (A4) nursery with a height of 1.8 m, covered with coconut tree straw and (A5) greenhouse with height of 4.0 m, covered with polyethylene film, with zenith opening and thermo-reflective cloth under the plastic. Trays of 72 (R1) and 128 (R2) cells were filled with 93% soil and 7% organic compound (S1), 86% soil and 14% organic compound (S2) and 79% soil and 21% organic compound (S3). It was used a randomized design in split-split-plot scheme, with five replicates (environments x trays x substrates). The greenhouses provide the best environments for the formation of cucumber seedlings. A tray of 72 cells is the best container, promoting more vigorous seedlings in substrate with soil and 7 or 14% organic compound.Ambientes de cultivo, bandejas e doses de composto orgânico foram avaliados na formação de mudas de pepino (Cucumis sativus L.). Cinco ambientes de cultivo foram testados: (A1) estufa agrícola com altura de 2,5 m coberta com filme de polietileno; (A2) viveiro com altura de 2,5 m, tela de monofilamento com 50% de sombreamento; (A3) viveiro com altura de 2,5 m, tela termorrefletora, com 50% de sombreamento; (A4) viveiro com altura de 1,8 m, coberto com palha de coqueiro, e (A5) estufa agrícola com altura de 4,0 m, coberta com filme de polietileno, com abertura zenital e tela termorrefletora sob o filme. Bandejas de 72 (R1) e 128 (R2) células foram preenchidas com 93% de solo e 7% de composto orgânico (S1); 86% de solo e 14% de composto orgânico (S2), e 79% de solo e 21% de composto orgânico (S3). Utilizou-se um delineamento inteiramente casualizado, em esquema de parcelas subsubdivididas, com cinco repetições (ambientes x bandejas x substratos). As estufas agrícolas propiciam os melhores ambientes para a formação das mudas de pepino. A bandeja de 72 células é o melhor recipiente, promovendo plântulas mais vigorosas no substrato com solo e 7 ou 14 % de composto orgânico