Effect of Desiccants on Seed Storability of Rice and Black gram Under Coastal Environment

Abstract

A study was undertaken to develop a simple, cost effective and practical seed storage technique using water absorbing desiccants for rice and black gram under coastal environment of Karaikal district of Puducherry (UT) during the year 2013. One kilogram of freshly harvested seeds of rice cv. ADT (R) 45 and black gram cv. ADT 3 were dried to moisture content of below 10% and stored in different containers with or without desiccants. In all the desiccant treatments, a seed: desiccant ratio of 1:0.350 was followed. Observations on seed moisture content (%), seed germination percentage, total seedling length (cm), vigour index, seed infection (%), insect infestation (%) and number of dead and live insects were undertaken at monthly intervals. The results revealed that a significant reduction or desorption of moisture in seeds was noticed during storage. Among the desiccants, seeds stored with "Zeolite" drying beads had lost higher moisture content followed by silica gel and rice husk. The desiccants didn't have a significant influence on the vigour and viability of seeds under ambient storage over a period of four months in rice. However, a significant reduction in germination was observed in black gram. Irrespective of the crops, a significant increase in seed infection was noticed during storage. Further, the level of infection in black gram was twice that of rice after four months of storage. Among the desiccants, drying beads and silica gel were found to be superior desiccants by registering the lowest seed infection in both the crops. Similarly, the desiccants had significant control over the multiplication of live insects in rice. Among the desiccants, silica gel, drying beads and rice husk were found to be the superior by registering significantly lesser number of live insects than other desiccants. The effect of desiccants on dead insects was also similar to live insects. Since, the effect of rice husk and charcoal on seed infection and infestation are comparable with drying beads, such low cost desiccants may be used with periodic regeneration for safe storage of high volume crop seeds.