Effects of cultivars,plant population density,pod position on the seed vigor

The effects of cultivars,plant population density,pod position on the seed vigor were studied.The results show significant differences of the tested seed size,standard germination,AA test,conductivity among cultivars.Standard germination and AA values of IA3013 are higher than those of FG1,while their conductivities are inverse and there is difference of tested items between their densities.Seed size of bottom pod is heavier than those of middle and top.Standard germination and AA test values are higher than those of top,the conductivity is lower than that of top.Interactions between PPD and pod position,cultivars and pod position are null.