Effects of hydrogen cyanamide and garlic extract on dormancy release, yield, and fruit quality of low-chill apple cultivars at Debre Tabor, northwestern Ethiopia

Résumé

Abstract Incomplete dormancy release due to insufficient winter chilling is a major constraint to apple ( Malus domestica Borkh.) production in tropical highland environments. This study evaluated the effects of hydrogen cyanamide (1.5%), garlic extract (15%), and their combined application on bud phenology, reproductive performance, yield, and fruit quality of three low-chill apple cultivars (‘Anna’, ‘Dorsett Golden’, and ‘Princesa’) under Ethiopian highland conditions over two consecutive seasons (2023–2024). Data were analyzed using a linear mixed-effects model with repeated measures across the two growing seasons. Dormancy-breaking treatments significantly advanced bud break by 15–24 days and shortened flowering duration from 7 to 8 weeks in the control to 3–5 weeks in treated trees. The combined hydrogen cyanamide + garlic extract treatment produced the earliest bud break and the highest flowering percentage (up to 67%), fruit set (up to 19%), fruit number (up to 63 fruits tree⁻¹), and yield (5.0–6.0 kg tree⁻¹) across cultivars. Yield improvement was associated with increases in fruit number and fruit weight. Significant cultivar × treatment interactions ( P < 0.05) were observed for most phenological and reproductive traits, demonstrating differential cultivar responsiveness to dormancy-breaking agents. Conversely, total soluble solids and fruit firmness were not significantly affected by treatment, cultivar, or their interaction ( P > 0.05). These findings indicate that combining low-chill cultivars with dormancy-breaking treatments partially compensates for inadequate winter chilling and improves apple productivity under tropical highland conditions.

Citer ce document

Accès au document

Texte intégral en lecture en ligne, réservé aux abonnés SPHAERO et aux membres de l'institution. Se connecter

Auteur(s)

Statistiques

Consultations : 1

Téléchargements : 0