Park Hyeonjin, Lee Younmi, Balaraju Kotnala, Kim Jungyeon, Jeon Yongho
Department of Plant Medicals, Andong National University, Andong 36729, Korea.
Agricultural Science and Technology Research Institute, Andong National University, Andong 36729, Korea.
Plant Pathol J. 2024 Dec;40(6):681-695. doi: 10.5423/PPJ.OA.05.2024.0076. Epub 2024 Dec 1.
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.
合成杀菌剂的应用已导致环境污染并对非目标物种产生不利影响。为减少农用化学品的使用，作物病害管理需要微生物生物防治剂。芽孢杆菌相关属会产生次生代谢产物来控制真菌病原体。从土壤中分离出的贝莱斯芽孢杆菌GYUN-1190对苹果炭疽病菌胶孢炭疽菌表现出拮抗活性。GYUN-1190产生的挥发性有机化合物和培养滤液（CF）在体外分别抑制胶孢炭疽菌生长80.9%和30.25%。在10^8 cfu/ml时，GYUN-1190的CF比细胞悬液更能抑制病原菌孢子萌发。此外，GYUN-1190的CF在体外有效抑制胶孢炭疽菌菌丝生长，并且在植物体内比GYUN-1190细胞悬液和吡唑醚菌酯更有效地抑制苹果果实苦腐病。与阳性对照和GYUN-1190细胞悬液相比，将胶孢炭疽菌浸入CF中48小时后，其菌丝生长被完全抑制。利用其全基因组序列确定了GYUN-1190生物防治特性的遗传机制，并与相似菌株进行了密切比较。它由4,240,653 bp组成，GC含量为45.9%，有4,142个编码序列、87个tRNA和28个rRNA基因。基因组研究发现了14个假定的次生代谢产物生物合成基因簇。该研究表明，贝莱斯芽孢杆菌GYUN-1190可能比化学杀菌剂更有效，并可发挥其作为生物防治剂的潜力。
