OSMOCONDITIONING AND DETERIORATION OF SOYBEAN SEEDS DURING STORAGE

Soybean seeds deteriorate quite rapidly when stored at high humidity and temperature and osmoconditioning prior to storage may reduce the rate of seed deterioration. To answer this hypothesis, soybean seeds were osmoconditioned with PEG 6000 solutions at –11.9 bars osmotic potential before storage at 15 and 35 oC for up to 6 months, and their germination, T, electrical conductivity and respiration rate were compared with that of untreated seeds stored under the same conditions. Untreated seeds stored at 15 50 C maintained a high level germination (from 100-70%) throughout storage period, while untreated seeds stored at 5 0C showed a rapid decline in germination and by 4 months of storage its seed viability was already less than 50%. At storage temperature of 35 oC, osmoconditioned seeds retained higher germination, germinated more rapidly and showed greater cell membrane integrity and higher respiration rate than untreated seeds irrespective of storage period. Therefore, it is concluded that osmoconditioning prior to storage slowed the rate of seed deterioration especially at high temperature of storage