Akademik Veri Yönetim Sistemi
APPLIED FRUIT SCIENCE, cilt.67, sa.5, 2025 (SCI-Expanded, Scopus)
The Botryosphaeriaceae fungal pathogens Botryosphaeria dothidea, Neofusicoccum parvum and Neoscytalidium dimidiatum cause considerable economic losses in nut trees, including pistachio (Pistacia vera), walnut (Juglans regia), hazelnut (Corylus avellana), and almond (Prunus dulcis). There are limited control strategies available, and therefore this study aimed to isolate and identify potential biological control agents (BCA), specifically endophytic and epiphytic bacterial species, from healthy trees and to characterize their antagonistic activity and plant growth-promoting (PGP) properties under in vitro conditions. A total of 74 BCA bacterial isolates were obtained, 48 of which were identified by MALDI-TOF MS and tested in dual-culture tests. Pseudomonas chlororaphis NKA10ep, Bacillus mojavensis NKA7en, and B. pumilus NKC3en BCA isolates showed the strongest antagonistic activity and inhibited mycelial growth by 75-84%. Volatile organic compounds (VOCs) from these strains suppressed or caused morphological changes in the fungal hyphae. The isolates exhibited several biocontrol mechanisms: 43 isolates produced siderophores, 35 isolates synthesized ammonia, 28 isolates secreted protease, and 4 isolates produced hydrogen cyanide. All isolates produced indole-3-acetic acid, and 17 isolates solubilized phosphate, indicating PGP potential. Among BCA bacterial isolates, Pseudomonas and Bacillus spp. In particular have strong biocontrol potential and PGP properties. These results emphasize the dual role of Pseudomonas and Bacillus spp. as effective biocontrol agents and plant growth stimulants. This study is the first to characterize the biocontrol potential and mechanisms of action of bacterial BCAs against Botryosphaeriaceae fungal pathogens in nut trees, highlighting their potential as a sustainable alternative to chemical fungicides.