Crop load affects yield, fruit size, and return bloom of the new apple cultivar Fryd© (‘Wuranda’) /
2025
Kviklys, Darius, | Martinussen, Inger,
The successful introduction of new cultivars depends on the evaluation of complex parameters essential for the consumers, market, and fruit producers. A new scab-resistant apple cultivar, ‘Wuranda’ (SQ159/Natyra®/Magic Star® × Honeycrisp), recently introduced in Norway and managed under the name Fryd©, is prone to biennial bearing. Therefore, one of the first tasks, investigated in Southwestern Norway by the Norwegian Institute of Bioeconomy Research, NIBIO-Ullensvang in 2021–2024, was the establishment of optimal crop load level based on the combination of productivity, fruit quality, and return bloom. The apple cultivar Fryd (‘Wuranda’) was propagated on ‘M.9’ rootstock and planted in 2019. The trial was performed in the same orchard for four consecutive years, starting three years after planting. Crop load level affected average fruit mass but had no impact on cv. Fryd fruit quality parameters at harvest such as blush, ground color, firmness, soluble solid content, or starch degradation. Fruit size variation was diminished by crop load regulation, and most fruits fell into 2–3 grading classes. Crop load, not the yield per tree, was the determining factor for the return bloom. The optimal crop load level depended on the orchard age. To guarantee a regular bearing mode of cv. Fryd planted on M.9 rootstock at a 3.5 × 1 m distance and trained as slender spindle, crop load of 5.5–6 fruits cm−2 TCSA (trunk cross-sectional area) in the 3rd year, 7.5–8 fruits cm−2 TCSA in the 4th year, and 6.5–7 fruits cm−2 TCSA in the 5th year should be maintained.
Показать больше [+] Меньше [-]