Produtividade de mandioquinha-salsa originadas de mudas propagadas em bandejas preenchidas com diferentes substratos

Abstract

The introduction of this culture in the country might have been in beginning of the past century, and it can be said the culture is still considered recent in terms of agricultural exploration and consumption, compared to others vegetables. The lack of planting material have been the limitating fator to the expansion of the culture because its high cost and difficulty to find. Thereby the aim of this work was to study and evaluate some features (survival and development) of Peruvian carrot seedlings propagated in tray with different substrates and the productivity of those plants after their cultivation in the field. The experiment stablished two phases, the first one was to propagate in trays using diferent substrates: Soil (S), Grit (A), Commercial substrate (Su), Soil + Grit (SA), Soil + Commercial substrate (SSu) e Commercial substrate + Grit (SuA). The treatments were arranged in randomized block design with six replications and the experimental unit was composed by 24 cells. The trays were allocated on workbenches covered with 50% luminosity shade cloth. Seedlings were evaluated in survial, height and diameter. The second phase were the cultivation at the field, using the seelings produced in the trays, keeping the initial treatment of the trays. It was used the experimental design randomized block, with four replications and the unit was composed by 21 plants. In the harvest, which happened 185 days after the transplant (DAT), were evaluated the fresh and dry mass of the leaf, overall, shoots, marketable roots, non-marketable roots. The maximum of survial number in the field was (87,16%), when the seedling were propagated in substrate Su, the greater height was (4,59 cm) in the substrate A and the diameter of the stalk was (6,16 mm) in the substrate SSu. In the cultivation at the field the greater leaf number was (27,06) and the greater survival plants number (20,67 mil ha-1 ) was obtained from seedlings pre-propagated in the substrate SA, the greater height maximum was (26,09 cm) and the greater diameter of stalk (37,36 mm) were obtained from the seedlings pre-propagated in the substrate Su. The highest yields of fresh (4,14 t ha- 1 ) and dry (0,68 t ha-1 ) mass of shoots were from seedlings pre-propagated in substrate SuA, for fresh and dry mass of marketable roots the largest production was from seedlings pre-propagated in the substrate SSu 8,67 t ha-1 e 1,67 t ha-1 , respectively, when the seedlings were pre-propagated in the substrate SSu. Based on the results obtained it can be concluded that the soil with the worst substrate that had been used for initial propagation in trays, higlighting the substrates Su, A and SSu according to the survial, height and diameter. At the field cultivation, the best plants to the production of marketable roots of peruvian carrot were the initially pre-propagated in substrate SSu.