The annatto plant is the only specie of the Bixa genera being originated in the Tropical America. Among the naturally occurring colorants, annatto (from seeds of Bixa orellana) ranks second in economic importance being the major producers Peru, Brazil and Kenya. The propagation, by seeds, presents some problems because seed germination is low caused by seed coat dormancy. This paper objective was to study the effect of the annatto seeds weight separation on physiological seed quality and improved germination treatments. The experiment was conducted splitting the original lot in four fractions named: light seeds, media seeds, heavy seeds and extra heavy seeds. Seeds were evaluated through determination of the hundred seeds weight, moisture content determination, germination test and dormancy overcome treatments as following: hot water for 1, 3 and 5 minutes, pre imbibition for 24 hours before hot water for 1, 3 and 5 minutes and mechanical scarification. Annatto seed separation, by weight, affected the physiological quality, bigger seeds had higher quality, however, with more hard seeds. Mechanical scarification, as a dormancy overcome treatment, was recommended in annatto seeds.
weight; physiological quality; dormancy; impermeability; annatto
