Studies on Physical Properties of Pelleted Onion (Allium cepa L.) Seeds

Abstract

Radish (Raphanus sativus) is one of the major vegetable crop grown throughout the country. It is widely grown in different parts of the country mainly by small and marginal farmers. The planting operation of the radish crop is not mechanized in India, with most of the area cultivated by line sowing and broadcasting operation. However, problem of flow of material are experienced. Pelletizing of the radish seed by providing a seed coat, helps in changing the physical characteristics of the seed. The biometric properties of seeds play an important role in designing seed metering device. Physical and engineering properties of radish seed both un-pelleted and pelleted (T0 , T1 , T2 and T3 ) were evaluated in the laboratory. The average major and intermittent dimension of T0 , T1 , T2 and T3 seed were 3.31 mm, 3.75 mm, 4.27 mm, 4.35 mm and 2.72 mm, 3.11 mm, 3.64 mm, 3.84 mm, respectively.T3 enhanced the major and intermittent dimension of seeds. Roundness value and sphericity of T0 , T1 , T2 and T3 seed were 0.70, 0.79. 0.82, 0.90 and 0.78, 0.84, 0.85, 0.91 respectively. The geometric mean diameter was maximum for T3 radish seed (3.94 mm) followed by T2 (3.65 mm), T1 (3.14 mm) and T0 (2.58 mm) radish seed. Thousand seed weight, W 1,000 of T0 , T1 , T2 and T3 was 11.74 g, 23.43 g, 32.86 g and 46.05 g respectively. Angle of repose and static coefficient of friction for mild steel surface were 28.81o , 25.09o , 23.70o , 23.16o and 0.82, 0.69, 0.65, 0.54 for T0 , T1 , T2 and T3 radish seed respectively. The values of porosity are decreased in gradually T0 , T1 , T2 and T3 seeds whereas the porosity for T3 seed was 44.51% and is the lowest amongst the other treatments. The porosity of T0 seed was the highest (47.78%).