Re: American Journal of Botany, Vol. 49, No. 5 (May - Jun., 1962)
Ben, I have read and re-read this paper and feel that the findings are very significant. It is amazing that more people here have not read this! There is so much here that answers many germination issues. Thanks for making me aware of it. I have adjusted my heat mat to the optimal high of 80-90 degrees F and the timer for 7 1/2 hours on and 16 1/2 hours off. Trying to find a location in my apartment to approximate the ideal low temp of 64-65 degrees.
It is also interesting to note that using a longer time of heat exposure beyond 9 hours, reduces germination percentages! Many people suggest 10-12 hours on and 12-14 off - which was my previous setting. In fact maintained temps over 95 degrees F may actually injure the embryo! They did find that an initial induction for 3 days of alternating between 95 degrees and 65 degrees, followed by reduction to 89 - 65 seemed to increase germination percentages a bit. I think everyone should read this.