RESULTS OF POLLINATION STUDIES OF SOME NEW PLUM CULTIVARS IN LATVIA

Abstract

One of the most important factors for the success of plum pollination and fertilization is the availability of a suitable pollinator. The aim of this study was to find the best pollinators in field conditions for new plum cultivars 'Adelyn', 'Lotte' and 'Sonora', which were submitted for registration in Latvia in 2010. Cultivars 'Experimentalfaltets Sviskon’, 'Jubileum', 'Julius', 'Minjona' and 'Victoria' were tested as pollinators in 2008-2010. Significant differences were found among cultivars and pollination combinations. The results were significantly different between years. The best pollination results for 'Adelyn' were with pollinator 'Victoria' (average fruit set after june drop - 66.5%). ‘Lotte’ showed the best results with ‘Minjona’ as pollinator (46.6%). 'Sonora' showed the best results of fruit set with ‘Experimentalfaltets Sviskon’ as pollinator (53.9%). The least suitable pollinator in all crosses was 'Julius'. An open pollination experiment was also established. Average fruit set after June drop for 'Adelyn' was 49.5%, for 'Lotte' 37.7%, and for 'Sonora' 53.3%. Only 'Sonora' showed self-fertility (33.5%) in the self-pollination experiment. Significantly higher results of pollination for all the cultivars (70.8% average fruit set) were obtained in 2008 while the results did not differ significantly in 2009 and in 2010.