Efeito de bioestimulante a base de algas na produção de mudas de girassol ornamental

Abstract

The sunflower (Helianthus annus) for ornamental purposes has been gaining space in the floriculture market, being a versatile specie, with several uses, such as: gardens ornamentation, cut flower and potted plant. The seedlings production is an important step in the production of ornamental sunflower. Works indicate the possibility of using substances known as biostimulants to improve efficiency in the production stage of seedlings; among these substances are some seaweed extracts that have shown a positive effect on plant growth stimulation. Therefore, the present work had as objective to evaluate the effect of biostimulant, based on the alga Ascophyllum nodosum, on the production of ornamental sunflower seedlings. The experiment was carried out in a randomized experimental design with four treatments (0, 1, 2 and 3 ml of water biostimulant L-1) and five replications, with ornamental sunflower seeds Dwarf cv. The analyzed variables were seedling emergence percentage and speed, plant height, number of leaves and root length. Were used 10 trays of 64 cells each one and a commercial substrate to the plants development. The results were submitted to variance and regression analysis. For the plants height and number of leaves we observed a good result in the growing curve during the 28 days, nevertheless the seaweed extract application does not promote improvements in the presented variables.