NOTA PRÉVIA Dormancy break in seeds of “ quina ” ( Strychnos pseudoquina A . St . - Hil

“Quina” (Strychnos pseudoquina A. St. Hil) is a medicinal plant species from the Brazilian Cerrado. As its seeds show dormancy, they were subjected to the treatments precooling at 5oC during 7 days, pre-heating at 40oC during 7 days, pre-soaking in sulfuric acid PA during 5 and 15 min, pre-soaking in boiling water during 5 and 15 min, pre-soaking in 100 and 200 ppm gibberellic acid during 48 h, pre-soaking in distilled water during 24 and 48 h, and mechanical scarification to break dormancy. Counts were daily conducted from the 2nd day after the experiment implementation until the germination stabilization at the 65th day. The germination speed index (GSI) and the germination percentage were evaluated. Germination rates above 96% were reached in seeds pre-soaked in water during 48 h and substrate moistened with water or KNO3.