OVERCOMING DORMANCY IN JATOBÁ SEEDS

Abstract

JATOB� IS A LEGUME WHOSE SEEDS HAVE DORMANCY, WHICH IS CAUSED BY A BLOCKAGE REPRESENTED BY THE RESISTANCE AND IMPERMEABILITY OF THE TEGUMENT. THIS IMPEDIMENT PREVENTS GAS EXCHANGE AND THE SEED OF THE WATER FLOW WITH THE EXTERNAL ENVIRONMENT, WHICH PREVENTS GERMINATION AND EMERGENCE OF SEEDS EVENLY. THE AIM OF THIS STUDY WAS TO EVALUATE THE MOST EFFICIENT METHOD OF BREAKING DORMANCY IN JATOB� SEEDS. THE SEEDS WERE SUBMITTED TO THE FOLLOWING TREATMENTS: MECHANICAL SCARIFICATION ON THE SIDE OF THE THREAD; MECHANICAL SCARIFICATION ON THE SIDE OPPOSITE THE THREAD; CHEMICAL SCARIFICATION WITH SULFURIC ACID (H₂SO₄) FOR 15 MINUTES; IMMERSION OF SEEDS IN HOT WATER FOR 5 MINUTES; IMMERSION THE SEEDS IN HOT WATER FOR 25 MINUTES; PRE-SOAK IN WATER FOR 24 HOURS; AND CONTROL TREATMENT. SEEDS WERE SOWN IN COMMERCIAL SUBSTRATE IN AN OPEN ENVIRONMENT, THE PLOTS WERE DISTRIBUTED IN A COMPLETELY RANDOMIZED DESIGN WITH FOUR REPLICATES, EACH PLOT WAS SCORED 20 SEEDS. FORTY-FIVE DAYS AFTER PLANTING WAS CONDUCTED TO COLLECT DATA AND ESTIMATE THE PERCENTAGE OF EMERGENCE, EMERGENCE SPEED INDEX AND PLANT HEIGHT. THE STATISTICAL ANALYSIS SHOWED A SIGNIFICANT EFFECT FOR TREATMENTS AS EVIDENCED DIFFERENCE IN ALL EVALUATIONS ACCORDING TO THE TREATMENTS USED. EMERGENCY RATES HIGHER THAN 90% AND IVE MORE EFFICIENT WERE OBSERVED FOR MECHANICAL SCARIFICATION, BECOMING THE BEST OPTION FOR JATOB� PROPAGATION.