Meiosis in garden roses

Meiosis in 96 varieties of garden roses was studied. While the euploid numbers were most frequent, in exceptional cases, aneuploid numbers were recorded. Intervarietal variation in chromosome pairing is reflected in the varying degrees of expression of univalents, heteromorphic bivalents, bivalents with double secondary constrictions and multivalents. Supernumerary fragments in addition to the euploid chromosome complement were recorded in three varieties. Three varieties of floribundas and one of hybrid polyanthas were chromosome numerical mosaics