Characterization and Biocontrol Efficacy of <i>Bacillus velezensis</i> GYUN-1190 against Apple Bitter Rot

Park, Hyeonjin; Lee, Younmi; Balaraju, Kotnala; Kim, Jungyeon; Jeon, Yongho

doi:2024.40.6.681

Plant Pathol J > Volume 40(6); 2024 > Article

Research Article

The Plant Pathology Journal 2024;40(6):681-695.
DOI: https://doi.org/10.5423/PPJ.OA.05.2024.0076 Published online December 1, 2024.

Characterization and Biocontrol Efficacy of Bacillus velezensis GYUN-1190 against Apple Bitter Rot

Hyeonjin Park¹, Younmi Lee¹, Kotnala Balaraju², Jungyeon Kim¹, Yongho Jeon¹

¹Department of Plant Medicals, Andong National University, Andong 36729, Korea
²Agricultural Science and Technology Research Institute, Andong National University, Andong 36729, Korea

Correspondence: Yongho Jeon, Tel: +82-54-820-5507, Fax: +82-54-820-6320,
Email: yongbac@andong.ac.kr

Received: 9 May 2024 • Revised: 10 November 2024 • Accepted: 15 November 2024

Abstract

The application of synthetic fungicides has resulted in environmental pollution and adverse effects on non-target species. To reduce the use of agrochemicals, crop disease management requires microbial biological control agents. Bacillus-related genera produce secondary metabolites to control fungal pathogens. Bacillus velezensis GYUN-1190, isolated from soil, showed antagonistic activity against Colletotrichum fructicola, the apple anthracnose pathogen. Volatile organic compounds and culture filtrate (CF) from GYUN-1190 inhibited C. fructicola growth in vitro, by 80.9% and 30.25%, respectively. The CF of GYUN-1190 inhibited pathogen spore germination more than cell suspensions at 10 8 cfu/ml. Furthermore, GYUN-1190 CF is effective in inhibiting C. fructicola mycelial growth in vitro, and it suppresses apple fruit bitter rot more effectively than GYUN-1190 cell suspensions and pyraclostrobin in planta. The mycelial growth of C. fructicola was completely inhibited 48 h after immersion into the CF, in compared with positive controls and GYUN-1190 cell suspensions. The genetic mechanism underlying the biocontrol features of GYUN-1190 was defined using its whole-genome sequence, which was closely compared to similar strains. It consisted of 4,240,653 bp with 45.9% GC content, with 4,142 coding sequences, 87 tRNA, and 28 rRNA genes. The genomic investigation found 14 putative secondary metabolite biosynthetic gene clusters. The investigation suggests that B. velezensis GYUN-1190 might be more effective than chemical fungicides and could address its potential as a biological control agent.

Key Words: anthracnose, Bacillus velezensis, biocontrol, Colletotrichum, growth inhibition