Heat Requirements of Prunus mume Cultivars for Flowering

Heat requirements play an important role in plant flowering, and control the flowering period of woody ornamental plants to a certain extent. In this study, the perennial potted seedlings of four typical Prunus mume cultivars 'Xiaolve', 'Baixuzhusha', 'Fenghou' and 'Danfenghou' were used as materials. The way of regulating the cultivation temperature is adopted to achieve the purpose of relieving the natural dormancy and forcing the blooming of P. mume. Its content includes the research on the heat requirements of P. mume cultivars widely planted in Beijing, and the analysis of the influence of different facility cultivation temperatures on the flowering characteristics of P. mume, providing a theoretical basis for further exploring the cultivation techniques of P. mume bonsai flowering regulation. The results showed that, according to the Growing degree-hour model, the HR of 'Xiaolve', 'Baixuzhusha', 'Fenghou' and 'Danfenghou' flower buds were 3583.70 GDH℃, 3217.30 GDH ℃, 3996.50 GDH ℃, 4732.20 GDH ℃, respectively. According to the effective accumulated temperature model, the HRs of above cultivars were 350.65 ℃, 319.30 ℃, 510.30 ℃, 558.50 ℃, respectively. In addition, the temperature of different cultivation facilities did not significantly change the flowering quality such as flower diameter and fragrance. Temperature also affects the growth and development speed, affecting the flowering time. Under the facility environment with higher temperatures, the flowering process is faster and the flowering period is shorter.