AR SECO E AQUECIDO NO PROCESSO DE DORMÊNCIA E GERMINAÇÃO DE SEMENTES DE Urochloa humidicola

• Published in: Colloquium agrariae Vol. 10; no. 1; pp. 9 - 25
• Main Authors: Pereira, Antonio Marcelo, Abrantes, Fabiane Lima, Machado-Neto, Nelson Barbosa, Custódio, Ceci Castilho
• Format: Journal Article
• Language: English; Portuguese
• Published: University of Western Sao Paulo, UNOESTE 29-06-2014
• Subjects: drying; heated air; Quícuio da Amazônia; seed vigor; sulfuric acid
• ISSN: 1809-8215; 1809-8215
• DOI: 10.5747/ca.2014.v10.n1.a096

Sulfuric acid (H2SO4) has shown effectiveness in overcoming dormancy, but its use carries effective workers and environmental risks. The objective of this work was to study the sulfuric acid treatment effectiveness, recommended by the RAS, and the use of ventilation with dry, heated air to overcome the dormancy and germination performance of six seed lots Urochloa humidicola cv. Tully. Comparison between the physiological effects of heat treatments at 45, 55, 65 and 75 ºC, with periods 24 and 48 h and chemical scarification (immersion in concentrated H2SO4) for 10 min, constituting eight treatments and two controls was performed. The seed germination, the germination velocity index, the tetrazolium test and seedling dry weight was evaluated. The use of controlled temperatures and of H2SO4 are mechanisms to overcome dormancy, but in lots with greater vitality were equal to conventional treatment with sulfuric acid results and can be considered as an alternative. In general, the work did not show the best indicated time (24 or 48 h) for use with dry air ventilation, however a temperature of 60 °C for lots of high vitality (L1, L3 and L5) might be recommended. The H2SO4 in plots with high vitality was not statistically significant compared to control, but for lots with less vitality occurred physiological deterioration of seeds.