ABSTRACT
Response of pruning severity on yield and fruit quality of ‘Duke’ highbush blueberry (Vaccinium corymbosum L.) under deficit irrigation

Emilio Jorquera-Fontena1*, Vanessa Huerta-Mendoza1, Jorge González-Villagra2, Ricardo Tighe-Neira1, Rafael López-Olivari3, and Josefina Bota4
 
Blueberries (Vaccinium corymbosum L.) are highly demanded by consumers; however, increasing water limitations for irrigation in many production areas may compromise fruit yield and quality. The aim of this study was to evaluate the combined effect of pruning severity and deficit irrigation on plant water status, yield, fruit quality and water productivity of ‘Duke’ blueberry. A field experiment was carried out during two growing seasons (2018-2019 and 2019-2020) in a commercial orchard in Chile (38°06' S; 72°52' W). Plants were subjected to slight or moderate pruning severity, and full (100% crop evapotranspiration [ETc]) or deficit (60% ETc) irrigation. Treatments were arranged in a completely randomized two-factor factorial design with four replicates per treatment combination. Stem water potential tended to decline throughout the season, with more favorable water status in moderate- than slight-pruned plants under deficit irrigation. Slight pruning increased yield by 36% and 21%, whereas moderate pruning increased berry size by 9% and 12% in the first and second seasons, respectively. Deficit irrigation reduced berry size but increased water productivity by 26% and 22% across seasons, without affecting yield. Pruning significantly affected titratable acidity in both seasons, whereas changes in soluble solids were inconsistent across seasons. Berry firmness was unaffected by treatments. Overall, slight pruning favored yield, whereas moderate pruning favored berry size and plant water status. Deficit irrigation independently improved water productivity, highlighting the trade-offs between yield, fruit quality, and water use under water-limited conditions.
Key words: Fruit load, source-to-sink relationship, stem water potential, water productivity.
1Universidad Católica de Temuco, Facultad de Recursos Naturales, Temuco, Chile.
2Universidad Mayor, Facultad de Ciencias, Ingeniería y Tecnología, Temuco 4780000, Chile.
3Instituto de Investigaciones Agropecuarias, INIA-Carillanca, Vilcún, Chile.
4Universitat de les Illes Balears, Institut d’ Investigacions Agroambientals i d’Economia de l’Aigua (INAGEA), 07122 Palma, Illes Balears, España.
*Corresponding author (ejorquera@uct.cl)
Received: 18 June 2026; Accepted: 13 September 2026, Available online: 29 October 2026.