Study shows pruning timing reduces apple canker risk in Chile

Apple growers in Chile’s Maule region may have a new tool to fight the canker disease caused by Botryosphaeriaceae fungi. A recent study by Adrián Valdez-Tenezaca, Bernardo A. Latorre, and Gonzalo A. Díaz has shown that the timing of pruning plays a decisive role in reducing infection risks.

The researchers tested Fuji and Gala apple trees and confirmed that pruning wounds are most vulnerable to infection immediately after cutting, especially within the first 15 days. Older wounds (30–45 days) proved significantly more resistant. Among the fungi analysed, Neofusicoccum arbuti and Diplodia seriata were identified as the most aggressive, creating the largest necrotic lesions.

The study also linked rainfall to spore release, noting that over 70% of spores were dispersed during rainy periods between June and August. Early pruning in June coincided with higher spore presence and led to more severe infections, while later pruning in August produced smaller lesions.

Based on these findings, the authors recommend delaying pruning to drier periods, reducing the overlap between fresh wounds and peak spore dispersal. This simple adjustment could help apple producers in Maule and beyond limit losses from canker and improve orchard health.

Read the full study here.

source: frutasdechile.cl

photo: arbolesmuyvivos.com