Comprehensive Analysis of Flowering Patterns in One-Year-Old Long Shoots of Apple Cultivars with Contrasted Bearing Habits

Abstract

Before developing orchard management strategies, it is crucial to conduct architectural analysis at the shoot level for the specific type of fruit to be grown. The objective of this study was to analyze flowering patterns in 1-year-old long shoots of three apple cultivars ('Amasya,' 'Braeburn,' and 'Granny Smith') with different bearing behaviors. This analysis aimed to gain a better understanding of their growth dynamics and reproductive activities. The shoot was divided into three consecutive zones (proximal, median, and distal) based on node number. When comparing the number of floral and vegetative buds in the three zones along the shoot, less contrast was observed between alternate-bearing ('Amasya') and regular-bearing cultivars ('Braeburn' and 'Granny Smith'). However, a notable difference in floral bud quality variables was evident in shoot zones between biennial-bearing and regular-bearing cultivars. In 'Braeburn' and 'Granny Smith' with a regular bearing habit, floral bud quality variables remained stable along the shoot. In contrast, 'Amasya' shoots exhibited a gradual increase in floral bud quality from the proximal zone towards the distal zone. This study underscores the significance of floral bud quality, especially the properties of spur leaves along the shoot, in ensuring optimal and consistent productivity. Finally, with the exception of internode length, morphometric traits did not significantly differ between cultivars when considering the entire shoot. However, these differences became apparent when examining successive zones along the shoot.