Germinação e vigor de sementes de feijão mungo condicionadas em distintos ciclos de hidratação-desidratação

Abstract

The improvement of agricultural production techniques represents an important step for the continuous evolutionary agriculture process, especially those applied to seeds, such as physiological conditioning, which enables better results in the field. Hydro conditioning, using only water, is applied to the seeds before sowing, improving their germinative performance and vigor, thus ensuring a uniform, strong and productive plant stand. The aim of this work was to evaluate the germination and vigor of mung bean (Vigna radiata L.) seeds submitted to conditioning, with different hydration-dehydration cycles. The experiment was carried out in Seed Analysis Laboratory of Ceará Federal University, in Fortaleza, Ceará. One to three cycles of hydration-dehydration were carried out, with soak time of 6 hours in distilled water at 25ºC at the beginning of each cycle, followed by dehydration at 30ºC in the oven B.O.D., for 18, 42 and 66 hours, respectively. The design was completely randomized in a 4x3 factorial scheme (hydration-dehydration cycles x drying period). The treatments’ effect was evaluated by means of the following variables: germination percentage; first count; shoot and root growth; aerial part and root dry matter and emergency speed index (ESI). The hydration-dehydration technique proved to be efficient in increasing the ESI and dry mass of aerial part at one-cycle treatment; the results has shown that the greater the susceptible cycle number, the lower the germination and the vigor of mung bean seeds. The hydration-dehydration cycle submitted at 30ºC did not reduce the germination and vigor of the seeds after one hydration cycle, but successive cycles continuously reduced the germination and vigor rate of the seeds of Vigna radiata L.