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Thank you Henry. Very interesting. I hadn’t heard that both palustris and setigera are thought to be resistant to RRD. This summer I challenged setigera. I guess next year I need to try palustris.
Hypothesis: Some of our other North American species roses may also carry genes required to help fight off RRV:
Consider if all of our native North American roses encountered a similar pathogen to RRV ages ago, and that Stellata, and Palusrtris, are the only ones that managed to hang on to the best of those defenses to this day.
While the rest of the North American roses that survived that onslaught, or came into being later, gradually lost, or “turned off” bits and pieces of that special code required to beat back this “earlier RRV” to “focus” on other rosy issues.
It could well be that many of the great cultivars y’all have bred for the far north, utilizing North American genes, could have some very valuable “snoozing” bits of DNA in them for the RRV cause. Who knows, their bits could even strengthen what Stellata and Palusrtris may have lost too
Opinions?
RBx