Evaluation of pollen viability and fertility of triploid herbaceous peony cultivars
To fully understand the breeding potential of triploid herbaceous peony cultivars, and to promote the development of new peony cultivars and extend their culture in China, three triploid cultivars, 'Brightness', 'Roselette' and 'Coral Sunset', were selected to investigate their pollen viability and fertility. In addition, fluorescence microscopy was used to observe pollen germination and pollen tube growth on the stigma of the domestic diploid cultivar 'Fen Yu Nu', which was used as the female parent of the three triploid cultivars. Our results show that pollen viability of the three triploid cultivars was very low, being highest (6.7%) in 'Brightness' and lowest (2.2%) in 'Coral Sunset', and that the pollen grains of the three triploid cultivars had a very low germination rate on the maternal stigma, caused by very short pollen tubes that could not penetrate the stigma. Profuse callose was found in papillose cells of the stigma and pollen tubes and a large number of pollen grains detached from the stigma. Compatibility in interspecific hybridization of the same section of Paeonia is very low.
Wang, Y.J., Teixeira da Silva, J.A., Liu, J.X., Lu, Y.M. and Yu, X.N. 2017. Evaluation of pollen viability and fertility of triploid herbaceous peony cultivars. Acta Hort. (ISHS) 1171:137-142
Paeonia lactiflora, hybridization, pollen germination, pollen tube fluorescence, pre-fertilization barrier