Work

Summer pruning and pneumatic preharvest-defoliation affect the light distribution within the canopy and improve the fruit quality of two bicolored apple cultivars

Year: 2023

Type: article

Abstract: Pneumatic leaf removal on apple trees has become a standard practice in commercial orchards on bicolored apple cultivars.To get a better understanding of the physiological impact of this new technology on apple trees, two trials on cv.'Nicoter' and 'Rosy Glow' were conducted in commercial orchards located in South Tyrol (Italy) in autumn 2020 summer pruning, pneumatic preharvest-defoliation and their combination on light penetration and fruit quality inside the tree canopy.For this purpose, four treatments, namely untreated control (UTC), summer pruning (SP), pneumatic defoliation (PD), and SP in combination with PD (SP+PD), were compared.The results showed that summer pruning causes a compared with the untreated control.The light applying summer pruning and pneumatic defoliation.Photosynthetic active radiation (PAR) measurements in 2021 showed that the effects on light penetration pruning and pneumatic defoliation could be found compared to untreated control.On the contrary in both years, summer pruning and pneumatic defoliation whereas on cv.'Rosy Glow' only pneumatic defoliation in 2021 decreased fruit weight.Total soluble solids content of apples in both years was affected negatively on 'Nicoter' by pneumatic defoliation treatment.Color index and anthocyanin content were increased the tree canopy on both varieties by summer pruning and pneumatic defoliation treatments.This study of pneumatic defoliation on apple trees, obtained under real conditions.It underlines the importance of a correct use of both summer pruning and pneumatic defoliation to minimize their adverse effects.

Source: European Journal of Horticultural Science

DOI: 10.17660/ejhs.2023/032