Avaliação da emergência de plântulas e vigor de sementes de couve-flor osmocondicionadas.

Abstract

The research was conducted at the Agriculture Product Storage and Processing Laboratory of UAEAg/UFCG in partnership with the Seed Laboratory of the Phytotechnical Department of the Agrarian Sciences Center of UFPB/Areia to evaluate the effects of physiological conditioning on the emergence of seedlings and seed vigor in cauliflower (Brassica oleracea var. botrytis). Seeds from two lots, determined by vigor, were conditioned in a glycol polyethylene (PEG 6000) solution at -0.3 MPa and in distilled water for different periods at 25 oC; using unconditioned seeds as a control. The treatment effect on the physiological quality of the seeds was evaluated using emergence and vigor tests (first emergence counting, emergence speed, seedling length and dry weight). The experiment was completely random, with the treatment distributed in a 2 x 7 x 2 factorial scheme, represented by two forms of conditioning (PEG 6000 and H2O), seven hydration periods (00, 12, 24, 36, 48, 60 and 72 hours) and two seed lots (low and high vigor), with four repetitions of 50 seeds per treatment. The PEG solution osmotic conditioning resulted in a bettering of the performance of the high vigor lot seeds. This result was the most apparent in the first counting and the emergence velocity index. This simple conditioning technique may become an efficient and practical method for bettering seed performance, promoting emergence uniformity and speed. The results also indicate that for use on a commercial scale, this technique should be studied with all species or specific genotypes to understand the physiological mechanism that act during the conditioning.