Abstract:

The study aims to clarify the different growth types of common bean flower bud differentiation, growth and development, and changes in physiological characteristics. By using trailing common bean ‘Jiangjun’ and dwarf common bean ‘Renaya’ as materials, the beginning and duration of each stage in the early development period were compared. The absolute growth rate, protein content and photosynthetic index were determined. In addition, the differentiation regularity and morphological structure of flower buds were observed. The results showed that the duration of the seedling stage and flowering stage of ‘Renaya’ was 15 days and 10 days shorter than those of ‘Jiangjun’ respectively. The absolute growth rate of ‘Renaya’ within 15 days after emergence was 2.14 times that of ‘Jiangjun’, and the flowering stage of ‘Jiangjun’ was 2.12 times that of ‘Renaya’. Time of flower bud differentiation of ‘Renaya’ which was 15 days after emergence was 2-3 days earlier than that of ‘Jiangjun’. Most of the flower buds of ‘Renaya’ completed differentiation and development within 10 days, which was half the time of ‘Jiangjun’. The protein content of ‘Renaya’ during flower bud differentiation was significantly lower than that of ‘Jiangjun’, and the content in flowering stage was observably higher than that of ‘Jiangjun’. However, the photosynthetic indicators of ‘Renaya’ in each stage were significantly higher than that of ‘Jiangjun’. In conclusion, the dwarf common bean ‘Renaya’ has early flower buds differentiation and short flowering period. Its growth rate is first high then low, and the rate of change is relatively fast. ‘Renaya’ also has a higher rate of photosynthesis than the trailing common bean ‘Jiangjun’ of the same period. This study can provide planting references for dwarf common bean.

Key words: common bean, growth habit, development period, flower bud differentiation, morphology, physiological index