GA(3) in tomato seeds: effects on seed germination and early seedling development

Obtaining seedlings is a critical stage in the production of vegetables, interfering directly on the development and production of the crop. Therefore, seek to technologies that enable the formation of healthy and vigorous seedlings. In this sense, the objective, of this study was to evaluate the effect of treatment of tomato seeds with different doses of gibberellic acid used alone or in combination with other plant growth regulators on germination and initial growth of "Santa Clara" tomato seedling. The study was characterized as a factorial 2 x 6, conducted a completely randomized block. The factors studied consisted of using two sources of gibberellic acid (GA(3) solution and biostimulant) and six levels (0, 0.5, 1, 1.5, 2, 2.5 mg L-1), with four replications. Seeds were treated by soaking in GA(3) solutions containing, for one hour. In laboratory evaluated the germination, mean germination time and germination speed index, later in greenhouse was evaluated seedling emergence, the average time of emergency, emergency speed index and after 14 days were obtained the proportionality of seedling growth, dry mass of shoots and roots. It was observed that the application of GA3 as biostimulant results in better germination rate index of germination and root growth when compared to the application of phytohormone separately. Increasing doses of GA(3) to 2.5 mg L-1, is detrimental to the emergence time and root development.