EMERGÊNCIA E CRESCIMENTO INICIAL DA CANAFÍSTULA EM DIFERENTES SUBSTRATOS E MÉTODOS DE SUPERAÇÃO DE DORMÊNCIA

Abstract

The aim of this paper was to evaluate the influence of different methods of dormancy breaking and substrates in the emergence and early growth of seedlings canafístula (Peltophorum dubium (Sprengel) Taubert). The experiment was conducted in a randomized block design in a factorial 5 x 4, with five substrates, Bioplant®; 75% Bioplant® + 25% bagasse from sugar cane (75B+25BC); 50% Bioplant® + 50% bagasse from sugar cane (50B+50BC); 25% Bioplant® + 75% bagasse from sugar cane (25B+75BC); bagasse from sugar cane (100%) and four methods of breaking dormancy (control, mechanical scarification using sandpaper, immersion in hot water and scarification with concentrated sulfuric acid) with three replications of 12 seeds. We evaluated the index of emergency speed; average time of emergency; emergence percentage at 7, 14 and 28 days after sowing, the dry mass of shoot and root dry mass. Immersion in hot water and chemical scarification with sulfuric acid (98%) are efficient methods to overcome seedcoat dormancy in seeds of canafístula. The substrates Bioplant® and 75B +25BC provide higher initial growth of seedlings.