Pomegranate (Punica granatum L.) is a deciduous fruit tree that requires exposure to winter chilling to overcome dormancy and resume growth in spring. The duration of chilling and subsequent heat requirements vary greatly among cultivars and influence budbreak and flowering regularity. Information on these thermal requirements is still limited, especially for cultivars grown in Mediterranean environments. In the 2024-2025 winter season, chilling and heat requirements of four cultivars were evaluated under controlled conditions: two local genotypes from Puglia (‘A Dente Molfetta’ and ‘Acido Torrelonga’) and two international cultivars (‘Wonderful’ and ‘Fleischman’) were evaluated for this aspect. One-year-old shoots were subjected to different chilling treatments (0-600 h at ≤7.2°C) and subsequently transferred to forcing conditions to monitor budbreak. Chilling requirements (CR) were estimated using the Weinberger model, while heat requirements (HR) were expressed as growing degree hours (GDH) according to the Richardson model. Results showed clear differences among cultivars: CR ranged from 100 to 500 h, while HR varied between 1922 and 3325 GDH. Local genotypes and ‘Fleischman’ released dormancy earlier, whereas ‘Wonderful’ required longer exposure. Budbreak was highest between 300 and 400 h of chilling. These findings provide novel insights into the adaptability of local and international pomegranate cultivars to Mediterranean conditions.
Comparison of chilling requirements among pomegranate cultivars grown in Puglia, southeastern Italy
Pitardi, S.;Pesole, A.;Mazzeo, A.;Palasciano, M.;Ferrara, G.
2026-01-01
Abstract
Pomegranate (Punica granatum L.) is a deciduous fruit tree that requires exposure to winter chilling to overcome dormancy and resume growth in spring. The duration of chilling and subsequent heat requirements vary greatly among cultivars and influence budbreak and flowering regularity. Information on these thermal requirements is still limited, especially for cultivars grown in Mediterranean environments. In the 2024-2025 winter season, chilling and heat requirements of four cultivars were evaluated under controlled conditions: two local genotypes from Puglia (‘A Dente Molfetta’ and ‘Acido Torrelonga’) and two international cultivars (‘Wonderful’ and ‘Fleischman’) were evaluated for this aspect. One-year-old shoots were subjected to different chilling treatments (0-600 h at ≤7.2°C) and subsequently transferred to forcing conditions to monitor budbreak. Chilling requirements (CR) were estimated using the Weinberger model, while heat requirements (HR) were expressed as growing degree hours (GDH) according to the Richardson model. Results showed clear differences among cultivars: CR ranged from 100 to 500 h, while HR varied between 1922 and 3325 GDH. Local genotypes and ‘Fleischman’ released dormancy earlier, whereas ‘Wonderful’ required longer exposure. Budbreak was highest between 300 and 400 h of chilling. These findings provide novel insights into the adaptability of local and international pomegranate cultivars to Mediterranean conditions.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
