Effect of storage temperatures and seed moisture contents on viability of Brassica juncea seeds

Freshly harvested seeds of mustard (Brassica juncea cv Pusa bold), were conditioned to five different moisture levels viz., 15,10,7,5,2.5 and 1 per cent. These were packed in tri-layered aluminium foil packets and stored at five different temperatures i.e. ambient, 20, 4, -10 and -20° C. Viability measurements were made at three months interval. The results indicated that the seeds stored with 15% moisture lost their viability earlier as compared to seeds at lower moisture contents. The seeds stored at ambient temperature were the first to lose viability followed by those stored at 20,-20 and _10° C. Viability was relatively prolonged when the seeds are stored at 10° C. Seeds stored at 10 per cent moisture content maintained high viability for the entire period of the study at all temperatures of storage except the ambient and 20° C where the viability was lost in 9 and 18 months respectively. Lowering the seed moisture to 7 per cent and below could prolong the storage life even at ambient conditions.