Annual Growth Rhythm of 1-year-old Seedlings of Three Cornus Species

Abstract:

In order to reveal the growth rhythm of Cornus, the height and ground diameter of one-year-old seedlings for C. florida, C. hongkongensis and C. hongkongensis subsp. tonkinensis were observed. According to the fitting analysis using Logistic equation for three Cornus seedlings (R²>0.98, P<0.01), the seedling growing process of both height and ground diameter could be divided into 3 stages, including initial stage, fast stage and later stage. Among three stages, the seedling growth of height and ground diameter at fast stage accounted for 55.23%-59.06% and 59.46%-60.71%, respectively. The annual growth accumulation of C. florida were larger than the other two evergreen Cornus species, while the seedling growth patterns of height and ground diameter for C. hongkongensis and C. hongkongensis subsp. tonkinensis were similar. The starting time of initial and grow fasting stages of C. florida were earlier than that of two evergreen others, but the duration of two stages of C. florida were also shorter than that of evergreen ones. In conclusion, the growth rhythms of height and ground diameter of one-year-old seedlings of three Cornus showed the similar pattern of "slow-fast-slow", according with "S" shape. Moreover, the growth of height and ground diameter of Cornus seedlings was allometric. So, these would provide the theoretical foundation for cultivation promotion, introduction and domestication of Cornus.

Key words:Cornus;Growth rhythms;Growth curve;Allometric growth