Current commercial roses have lost more than a quarter of their genetic diversity compared to older varieties, potentially making them more vulnerable to disease and climate change.
Roses have been admired and cultivated since ancient times. People in Asia and Europe began cultivating ancient varieties from more than a dozen wild roses. Before 1800, there were less than 100 varieties, but by 1900 there were about 8000 varieties, combining Asian and European varieties.
Source: www.newscientist.com