plant dormancy in different locations
It might depend on the signal that the seed uses to end dormancy. Some seeds require 'vernalisation', that is a prolonged period of low temperatures, for them to germinate successfully.  If they don't have the cold period, they don't germinate because they 'think' that they haven't had winter yet.

Dormancy can also depend on the conditions that the parent plant lived under, so it is quite possible that if two plants were grown in different environments, their seeds would have differences in dormancy. This study looked at that effect in the 'model plant' Arabidopsis thaliana:
Donohue K., Dorn L., Griffith C., Kim E., Aguilera A., Polisetty C. R., Schmitt J. Environmental and genetic influences on the germination of Arabidopsis thaliana in the field. Evolution. 2005;596(1):740–757.

This paper gives a good review of Seed Dormancy and Germination in Arabidopsis from a few years ago:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3243337/#i1543-8120-70-1-1-b60