EFFECT OF SEED SOAKING DURATION ON GERMINATION AND OTHER PHYSIOLOGICAL PARAMETERS OF CASTOR (RICINUS COMMUNIS L.)Nithyadevi, G., Jerlin, R., Thirusendura Selvi, D. and Thiyagarajan, R.
Castor (Ricinus communis L.) is a commercially valued bioenergy crop highly suitable for marginal lands. Slow and uneven germination are the common phenomenon of castor seeds when sown under stressful environmental conditions. Castor seeds that have been soaked in water can germinate quickly and uniformly. When seeds are soaked in water, the duration of time they are soaked has a significant impact on their performance. In the present investigation, castor seeds were soaked for different durations viz., 6,8,10,12,14,16,18,20 and 22 hrs at 1:2 ratio. Among different soaking durations, 16 hrs improved the seed physiological parameters, viz., the speed of germination, germination percentage, vigour index, root length (cm), shoot length (cm), dry matter production (g/10 seedlings), when compared with other durations. An improvement of 16% germination over the dry control seeds was also noticed when the castor seeds were soaked for 16 hrs in water at a1:2 ratio.