Testing of self-(in)compatibility in apricot cultivars using fluorescence microscopy

Self-incompatibility is common in apricot (Prunus armeniaca L.) cultivars of Central Asian and Irano-Caucasian ecogeographical groups, while cultivars of European group are traditionally considered as self-compatible. However, the number of known self-incompatible cultivars of the European group has increased rapidly over the last two decades. This can be explained by using Asian or North American self-incompatible cultivars in breeding programs that aim to create new genotypes with the traits including: Plum Pox Virus resistance, frost tolerance, increase of the sugar content or extending the harvest time. In this work self-(in)compatibility was tested in 38 apricot cultivars. Pollen-tube growth in pistils pollinated in laboratory was analysed using fluorescence microscopy. Cultivars were considered self-compatible if at least one pollen tube reached the ovary in the majority of pistils. In self-incompatible cultivars growth of pollen tubes in the style of pistil stopped along with formation of characteristic swellings. Of the examined cultivars, 17 were self-compatible, and 21 were self-incompatible