Impact of storage period of soybean seed on lipids peroxidation, soluble sugars, protein, electrical conductivity, quality characteristics and seedling emergence

In order to evaluate the variations of soybean seed quality and also biochemical changes during seed deterioration at natural aging conditions, this research employed a factorial experiment based on a completely randomized design (in laboratory) and randomized complete block design (at field). The treatments included two cultivars of Williams and L17 and three storage durations of 6, 18 and 30 months. The studied characteristics included normal seedling percent, electrical conductivity, soluble sugars, total protein, malondialdehyde, first and final seedling emergence percent and cumulative seedling emergence rate. The result showed that seed quality significantly decreased by increasing the storage duration and this loss of seed quality storage resulted in the reduction of field seedling emergence. The reduction of seed quality in the third duration was significantly higher than the second storage duration. Also, the cultivar Williams had more storability as compared to L17. The number of normal seedlings decreased more significantly 5 and 17.8 percent for Williams and 12.9 and 25.8 percent for L17 subsequent to 18 and 30 months as compared to 6 months of storage. The results indicated a positive correlation between seed quality and seed’s soluble sugars and protein and also a negative correlation between leakage of cell substances and the rate of MDA in seeds. Total protein percent decreased from 36.5% (6 months of storage) to 33.5% and 31.5% (18 and 30 months of storage). Results revealed that seed deterioration rate after 30 months of storage was significantly higher as compared to its previous period. This finding shows that soybean seeds was storable for at least one crop season and the decrease in the seed quality and emergence problem will then be witnessed.