Fates of buried Sorghum bicolor ssp drummondii seed

The emergence of Sorghum bicolor seedlings and the dormancy status and surv ival of S. bicolor seeds buried in soil in the midwestern United States wer e studied from 1992 to 1995. Possible causes of seed mortality were also in vestigated. Emergence of seedlings from seeds buried in November averaged l ess than 2%, compared with 28% from seeds buried in March. Seeds showed lit tle ability to survive winter, with more than 80% dying between November an d March and virtually none surviving a second winter Many seeds exhibited s igns of cold damage. Further evidence of the effect of cold was the decreas ed mortality of seeds protected somewhat from the cold. The decline in the viability of seeds was modeled well by negative exponential curves with an exponent of between 0.011 and 0.016.