Time series regression analysis between changes in kernel size and seed vigor during developmental stage of sh2 sweet corn (Zea mays L.) seeds

High vigor sweet corn seeds have higher yield potential than low vigor seeds. Relationships between kernel size and seed vigor during caryopsis development of three sh2 sweet corn (Zea mays L.) cultivars were analyzed by time series regression (TSR) analysis method. The pattern of kernel development among the three cultivars was similar and the length, width, thickness, volume, fresh weight and dry weight of the seeds reached their highest values at 30, 26, 18, 26, 26 and 38 days after pollination (DAP), respectively. Meanwhile, germination percentage (GP), germination energy (GE), germination index (GI) and vigor index (VI) gradually increased and reached their highest levels at 38 DAP. The TSR analysis indicated that seed dry weight affected seed vigor more significantly than other kernel size parameters did and was positively correlated with GP, GE, GI and VI. The results suggested that sh2 sweet corn seed vigor in different seed developmental stages could be predicted by seed dry weight.

► Relationships between kernel size and seed vigor were analyzed by TSR method.
► GP, GE, GI and VI reached their highest levels at 38 days after pollination (DAP).
► Six parameters of kernel size reached their highest values at different DAP.
► Regression formulas between kernel size and seed vigor were developed.
► Seed dry weight could be used to predict seed vigor in seed development stages.