Flower Morphology and Flowering Phenology of Clones of Cerasus sp.

In February 2015, 1-year shoots of 23 species (variety and cultivar) of Cerasus were collected from breeding nursery in Hangzhou, Zhejiang province. They were grafted on rootstock of 1-year C. pseudocerasus ‘Daqingye’. In the winter, grafted seedlings were planted by completely randomized block. In 2017, 12 individuals of each clone were randomized selected for determination of flower traits. Flowering phenology was observed at the same time. The results showed that it had significantly great difference of flower morphological traits among clones (P<0.01). C. serrulata ‘Superba’ had the largest flower diameter with 55.77 mm, while C. ‘Anhui’ the minimum. The calyx tube of C. × subhirtella ‘Omoigawa’ was the shortest, whereas that of C. ‘Pinklady’ was the longest. C. ‘Introrsa’ had the earliest flowering stage, whereas C. serrulata ‘Albo-rosea’ the latest. The flowering stage of different clone varied from 4 to 16 days, and the coefficient variation (CV) was 36.93% among clones. Principle component analysis on flower morphological traits and phenology demonstrated that the tested clones could be divided into three groups, like earlier, medium and later flower stage. Flowering phenology had close relation with temperature and atmospheric pressure. The correlation coefficients between early flowering date and the accumulated temperature and atmospheric pressure of 30 days before flowering were 0.985 and 0.973, respectively.