Answers are grounded in this paper and cite their sources.
Systematics and Genetics: Medicinal effects of rosehips are attributed mainly to dogroses, i.e. species in Rosa sect. Caninae. These are mostly pentaploid and have a unique meiosis with asymmetrical chromosome distribution. Offspring in reciprocal crosses differ widely since seedlings resemble the seed parent more than the pollen parent.
No takes yet. Share an insight, caveat, or question.
Nybom et al. (2016) studied this question.
Synapse has enriched 5 related papers. Consider them for comparative context: