Comparative evaluation of the biological characteristics of flower organs and fruits of the new Chinese blueberry cultivar Zhaixuan 4

To explore the advantages of the new blueberry cultivar ‘Zhaixuan 4’ and analyze the correlation between flower and fruit characteristics in blueberries, a comparison was made between the phenotypic and antioxidant characteristics of the flowers and fruits of ‘Zhaixuan 4’ and the introduced southern highbush blueberry varieties ‘Sharp Blue’, ‘O’ Neal’ and ‘Sunshine Blue’. The analysis also revealed correlations between the flower and fruit characteristics of the four blueberry varieties. The new cultivar ‘Zhaixuan 4’ presented smaller flowers, larger pollen grains, and more pollen, indicating a significant genetic advantage. It is suitable for use as parental material for independent selection and breeding. Although the fruits of ‘Zhaixuan 4’ are small, with less fruit powder on the surface, they have the highest anthocyanin and polyphenol contents among the four varieties. These findings suggest that ‘Zhaixuan 4’ is more suitable as a specialized cultivar for processing purposes and can serve as an excellent germplasm resource with high antioxidant properties for genetic breeding. The correlation analysis of flowers and fruits revealed significant correlations between several indicators. Based on these findings, the advantages of ‘Zhaixuan 4’ were verified, providing a basis for its popularization and exploitation. The results also offer theoretical support for implementing water and fertilizer interventions during the early flowering stage of blueberry cultivation, as well as expediting the breeding process of varieties.