Physical properties of seeds associated with viability and vigor of selected grain crop

Seed color had significant effect on the number of normal, abnormal, and non-germinable seeds. Normal seedlings for yellow-colored seeds had an average of 78.87 percent of normal seedlings from two varieties while green seed had an average of 14.00 percent. Tetrazolium test (TZ) for yellow-colored seeds revealed a significantly higher percentage of high, medium, and low vigor seeds than in green colored seeds. The percentage of non-germinable seeds were extremely higher in green-colored seeds than the yellow colored ones (Experiment 1). Specific gravity and seed size had a highly significant influence on the percentage of normal seedlings of corn, peanut, soybean, and bush bean. Small-light seeds, however, had the highest percentage of abnormal seedlings in practically all crops. The highest rate of germination was observed on small heavy and small-light seed with 90.00 and 91.00 percent, respectively (Experiment 2). TZ test for peanut, corn, soybean, and bush bean showed that the high, medium, and low vigor seeds were likewise significantly affected by specific gravity and seed size. On peanut, medium, and low vigor seeds were likewise significantly affected by specific gravity and seed size. On peanut, medium, and small size seeds exhibited higher percentages of high vigor seeds compared to large seeds. On the other hand, lighter seeds gave a significantly higher vigor seeds than the heavier seeds. A general trend was established for corn, soybean, and bush bean as to the role of seed size and specific gravity to seed vigor: larger and heavier seeds gave a significantly if not numerically higher percentages of seed of high vigor. Results indicated that standard germination test can not truly predict the real seed vigor of a given seed lot, hence, the presence of less sensitive index of the progress of deterioration and reduction in emergence potential of seeds during storage. TZ test significantly revealed a more reliable method to predict the true vigor of seeds.