Dormancy overcoming in seeds of Myrciaria glomerata O. Berg.

Abstract

Myrciaria glomerata O. Berg. (Myrtaceae) is a fruit tree native to the Brazilian Atlantic Forest with potential for use as food and medicine, besides having good ecological potential. However, this species is limited by low germination rates. Thus, this study aimed to evaluate different methods to overcome dormancy in seeds of M. glomerata and to improve seedling vigor. For this, two experiments were conducted. In Experiment 1, seven treatments were tested: a control treatment, immersion in water at 100 ºC for 30 seconds, immersion in concentrated sulfuric acid (H2SO4) for 1 and 5 minutes, immersion in an aqueous solution of gibberellic acid (GA3) at the concentrations of 250 and 500 mg L-1 for 24 h, and seeds homogenized with an aqueous solution of Stimulate® at a concentration of 5 mL kg-1 seed. In Experiment 2, six doses of Stimulate® were tested: 0, 5, 10, 15, 20, 25, and 30 mL kg-1 seed. The immersion of seeds in 250 and 500 mg L-1 GA3 contributes to increase germination rates, seed length, fresh mass, and dry mass compared to the control and the other methods tested. Immersions in water at 100 ºC and in H2SO4 are not recommended for M. glomerata. The treatment with Stimulate® at 15–25 mL kg-1 seed increased all characteristics analyzed. Immersion in 250 mg L-1 GA3 and Stimu-late® at 20–25 mL kg-1 seed efficiently stimulated seeds to overcome dormancy in M. glomerata, as well as improved seedling vigor.