Inflorescence Development and Composition of Gypsophila paniculata L. 'Bristol Fairy'

The inflorescence composition of Gypsophila paniculata L. 'Bristol Fairy' was evaluated over six growing periods to identify both regularity and plasticity in inflorescence development. An inflorescence (a flowering shoot) was regarded here as an aggregation of many inflores-cence units (dichasia) because of the hierarchical nature of its form. To identify seasonal changes in inflorescence composition, data was taken of whole inflorescences and their units.Inflorescence development was very regular. In individual inflorescence, there was corre-lation between the cross-sectional area of the stem and the number of florets. In an unit, the highest order of visible florets, the number of florets, and the fresh weight were correlated with the diameter of the inflorescence unit axis.G. paniculata L. had considerable plasticity in inflorescence development. The inflorescence composition changed with the date of planting. From spring to summer, the days to flowering, fresh weight of the inflorescence, stem length, number of nodes, number of primary and secondary branches, and number of florets tended to decrease, but in units, the fresh weight, diameter of the inflorescence unit axis, highest order of visible florets, and number of florets tended to increase.