CLONAL SELECTION IN PRUNUS MAHALEB ROOTSTOCKS
In order to get clonal rootstocks for sour cherry culture on light soil Prunus mahaleb plants were produced from root suckers of vigorous growing and high cropping "Schattenmorelle" trees considered to be compatible with the mahaleb rootstock. The mahaleb plants were propagated as green cuttings under mist and indexed for virus infections. Among 76 plants only two carried Prunus necrotic ring spot virus. No other viruses could be detected. According to morphologic characteristics the mahaleb plants could be grouped to four different types. These types varied in some important properties, i.e. percentage of rooting, growing of the rooted cuttings, performance in the nursery, bud-take, development of the young scions. However, when individual clones were propagated from these types also considerable variation could be stated between clones of the same type. Therefore clonal selection is considered to be one of the most important things to begin with in the production of virus-free propagation material.
Concerning criteria of selection at least 4 of the mahaleb clones produced gave promising results and will now be tested under orchard conditions.
Baumann, G. (1977). CLONAL SELECTION IN PRUNUS MAHALEB ROOTSTOCKS. Acta Hortic. 75, 139-148