Identifying self-incompatibility alleles in selected hazelnut genotypes
Hazelnut industry has newly formed and is developing rapidly in Ontario, Canada, due to the expanding market and public interest for diverse horticultural crops. The hazelnut industry has to face a few challenges to thrive. The major one is the need for new cultivars that are winter hardy and resistant to Eastern Filbert Blight disease, endemic in eastern North America. The next step is to identify the self-incompatibility alleles to ensure fertilization and nut formation. Up to now, about 33 alleles have been identified in hazelnuts and each genotype carries two alleles. The traditional method to identify the alleles in a genotype is to look at the pollen tube growth of controlled crosses under fluorescent microscopy. This method needs the access to fresh pollen of 33 specific hazelnut genotypes with known S-alleles as a source of pollen and mature hazelnut tree with unknown S-alleles as female flowers. The method is also labour intensive and time-sensitive. Several attempts have been made to develop molecular markers to identify S-alleles in early stages of growth; however, few markers were developed with variable results. The goal of this experiment is to further understand the genetic base of self-incompatibility in hazelnuts. Twenty genotypes were selected, some with known and the rest with unknown S-alleles. Female flowers were self-pollinated and RNA from styles was extracted, sequenced and aligned de novo. Primers will be designed based on their homology with s-alleles of brassica and plants with similar incompatibility mechanism. The primers will be validated using DNA of the selected hazelnut genotypes and cultivars.
Taghavi, T., Rahemi, A., Dale, A., Munholland, S., Chia, L.-S., Crosby, W. and Kelly, J. (2019). Identifying self-incompatibility alleles in selected hazelnut genotypes. Acta Hortic. 1231, 157-160
Corylus, S-genotype, pollen, fertilization, fruit set, style