Drying and storage studies of toria (Brassica campestris L.) Seed

The drying of seed is one of the most important operations in seed production. The seed is dried to a safe moisture content level for storage to avoid high rate of respiration and mold growth. Seed, if dried, to a recommended moisture content could be stored for long period without loss of viability. So for the present studies, fresh toria (Brassica campestris L.) seed (variety TL-15) at moisture content of 13.0% d.b. (11.5%w.b.) was procured from farms of Punjab Agricultural University during year 2005. It was dried in electrically operated mechanical drier and through sun drying for seed purpose. The temperature in the mechanical drier was maintained at 45°C. The effective drying time was 5.30 hrs and 6.30 hrs in mechanical drier and through sun drying, respectively, to bring down the moisture content to a level of about 7.13% d.b. (6.65%w.b.) After drying, the seed was stored in 1.5 kg capacity cloth bags at room temperature. During storage, moisture content, 1000-grain weight, vigour index, germination (%), insect-infestation (%) and mycoflora incidence (%) were studied bimonthly. During the study, it was observed that the 1000-grain weight and germination per cent remained constant and thus indicating that both the methods of drying were equally effective in maintaining the seed quality. The seed was kept free of insect-infestation during the storage period. Mechanically dried seed had lesser mycoflora as compared to sun dried seed. The studies were terminated after 8 months as the germination percentage started declining. Thus looking into energy expenditure and environmental benefits, sun drying of toria seed can be considered as an alternative to energy consuming electrically operated mechanical drying.