Evaluation of Branching Characteristics and Their Contribution to Yield in Everbearing Strawberry Cultivars under Forced Cultivation

　Enhancing continuous flowering in cultivated strawberries may result in insufficient photosynthetic products due to the lower limit of leaf number on each lateral shoot, leading to reduced yield and fruit quality. If strawberries could differentiate an appropriate number of tillers and allow each tiller to grow autonomously with sufficient leaf number on each lateral shoot, rather than flowering continuously on the main bud alone, plants could achieve high yields while preventing plant weakening and fruit quality deterioration. Therefore, this study evaluated branching characteristics of everbearing strawberry cultivars under forcing cultivation to identify cultivars with moderate tillering and moderately low continuous flowering. Pot experiments revealed that the number of tillers was high in ‘Summer Princess’ and ‘Miyazaki-natsuharuka’ but low in ‘Summer Berry’ and ‘Suzuakane’. This trend was independent of total number of lateral shoots, nodal position of first inflorescence, and the number of leaves on each lateral shoot, which serve as indicators of continuous flowering ability. Among seven tested cultivars, ‘DT17’ and ‘Miyazaki-natsuharuka’ showed intermediate values with 2.1 - 2.5 tillers per plant and 6.7 - 7.7 leaves on each lateral shoots. These cultivars showed yields of 747.0 - 1,028.5 g per plant under forcing cultivation, which were higher than other cultivars, along with consistent fruit quality. These results suggest that improving branching characteristics is a practical approach to enhancing fruit productivity in strawberries.

原著論文 (Original paper)