Abstract

Seed storage is being affected by factors viz. seed moisture content, temperature and relative humidity. The effects of four drying methods using silica gel, saturated salt solution of lithium chloride, concentrated sulphuric acid and dryer drying on different physiological and biochemical characteristics of genotypes CSH 16 and CSV 18 of sorghum (Sorghum bicolor (L.) Moench) were investigated. Faster drying rate was observed in acid and silica gel while dryer and saturated salt solution of lithium chloride exhibited slow drying rate. Acid drying was efficient in drying, but detrimental to the seed quality. Results obtained by silica gel and lithium chloride salt solution drying were comparable with those obtained by seed dryer. Among the various parameters investigated, germination, vigour, total protein content, dehydrogenase, amylase, superoxide dismutase (SOD) and peroxidase activity were found to show a decreasing trend, whereas electrical conductivity (EC) increased during storage irrespective of drying methods. Seed quality was preserved in conventional drying method (drying chamber at 15°C and 15% R^H), which was comparable to the quality of seeds dried using lithium chloride; though drying rate was slow. Silica gel resulted in faster rate of drying to maintain moisture content and seed quality.

Key words: Sorghum, silica gel, acid, dryer, lithium chloride, drying methods, seed quality.