Specific gravity in rice grains: its implication on seeds quality.

Abstract

Size and specific gravity (SG) of seeds affects their quality and, in rice, these variations explain differences. In order to relate morphometric variables with physiological quality parameters, length, width, weight of 1000 seeds, germinating power and energy, plant stand and vigor were evaluated in 4 rice cultivars fractionated by SG. The percentage distribution of SG categories differs between cultivars. The seeds ranged between 9.30-10.50 mm in length and 2.41-2.75 mm in width, with significant effects of cultivar and SG. In 1000 seeds weight, PAC 103 stood out for its greater mass and a gradient was evidenced according to the SG category. Germinating power, percentage of normal and abnormal plants and ungerminated seeds, germination energy and plant stand were affected by SG. Seeds with PE <1.14 g/cm³ showed a worse performance in these parameters.