Temporal Susceptibility of Grapevine Pruning Wounds to Botryosphaeriaceae Host-Jumping Pathogens in Central Chile

Botryosphaeria dieback, caused by species of Botryosphaeriaceae, causes significant economic losses by infecting pruning wounds in vineyards and fruit trees. Previous studies have shown that pruning wounds constitute the main entry point for Botryosphaeriaceae and that isolates from different fruit hosts can infect these tissues regardless of origin. This study assessed the temporal susceptibility of Vitis vinifera pruning wounds in four cultivars (Cabernet Sauvignon, Malbec, Merlot, and Sauvignon Blanc) to six Botryosphaeriaceae isolates from different fruit hosts (grapevine, apple, blueberry, and walnut) under greenhouse and field conditions in central Chile. Pruning wounds were inoculated at 1, 15, 30, 45, and 60 d after pruning, and lesion length and wound infection (%) were evaluated. Both variables decreased with increasing wound age in greenhouse and field trials. Wounds were most susceptible during the first 15 d after pruning, with a marked reduction thereafter, although susceptibility persisted up to 60 d. Neofusicoccum parvum and N. arbuti showed the highest aggressiveness. All isolates were able to infect pruning wounds regardless of host of origin. These results indicate that pruning wounds remain susceptible for an extended period and highlight the importance of considering both wound age and cross-host inoculum sources in disease management strategies.