North American pawpaw is a temperate species in the mostly tropical Annonac
eae. 4 small proportion(12%) of the seed population used in this study germ
inated after removal from the fruit. The remaining seed required 8 weeks of
chilling stratification to satisfy dormancy. In addition, pawpaw seeds dis
played a moderate form of recalcitrance. Seeds lost 50% viability when seed
s were dried from their initial 37 to 25% moisture. Critical value for tota
l loss in viability was between 15 and 5% moisture. Also, following stratif
ication, pawpaw seeds germinated at 45% without additional water in the ger
mination medium. There was no significant effect of light or temperature (2
5, 30 or 20/30 degrees C) on standard germination. Seeds showed the best ge
rmination with Iml of water added to the germination medium in petri dishes
. For standard germination testing, pawpaw seeds should be stratified for 1
00 days at 5 degrees C followed by germination in rolled towels at constant
25 or alternating 20/30 degrees C. Light was not required and final germin
ation counts should be after 5 weeks.