Parameters influencing Magnolia grandiflora L. seed germination

The seeds of Magnolia grandiflora are diverse in weight, size and density; therefore this study was undertaken to measure these physical parameters and to determine their relationship to germination. Additional parameters of paired seed, non-paired seed, seed location within the aggregate, bloom period and harvest periods were also studied to determine their relationship to germination.

The blossoms of the Magnolia grandiflora trees were tagged each week and then harvested when matured. After seed collection the seeds were cleaned, weighed and their densities estimated by floatation. The seeds were planted and stratified for ninety days. After stratification was complete, a forty-five day germination test was conducted.

Data were analyzed using an analysis of variance for germination percent and it was determined there were no significant differences between trees, between weight groups, between seed locations on the aggregate or between paired and non-paired seed. The density classes of .91 g/ml and 1.0 g/ml had significantly higher germination percentages than the .78 g/ml and <.78 g/ml density classes. The later harvest period, November 21, 1985 resulted in larger germination percentages. Peak blossom was also determined and occurred near June 20, 1985.