미생물 제제의 범용 적용을 위한 후보 미생물의 다병원균 길항 활성 및 생장촉진 기능 평가

초록

The purpose of our study was to select candidate microbial strains as functional additives for fertilizer-based cropping systems by demonstrating their potential to both enhance plant growth and mitigate disease through microbial antagonism. We assessed the major pathogen-antagonistic and plant growth-promoting characteristics of seven isolates in tomato, pepper, and rice plants. In tomato wilt, the largest inhibition zone was associated with strain H2 grown on 1/5 Potato Dextrose Peptone (PDK) medium, whereas maximum inhibition was observed with strain H1 on 1/5 Tryptic Soy Agar (TSA) medium. In tomato anthracnose, we observed consistently strong inhibition with H2 and R5 in both media. In pepper, only H1 on 1/5 TSA suppressed Phytophthora blight. Strains H2, H4, R5 exhibited stable growth in their antagonism against pepper and rice pathogens, indicating comparatively stable activity. Regarding growth-promoting features, all the strains produced indole-3-acetic acid (IAA), with H3 producing the highest level. Other than H3, all the strains produced siderophore. The largest halo zones were recorded for H4 and R5. Although nitrogen fixation was not statistically significant, several strains showed notable enzymatic and colonization traits. R7 displayed high protease activity and strong biofilm formation, while H2 exhibited the highest cellulase activity and robust biofilm formation. Our combined results suggest that H2, H4, and R5 (and, in part, R7) are promising candidates to develop as fertilizer-compatible microbial additives that can both improve crop vigor and reduce disease pressure through multiple mechanisms (antibiosis, iron competition, extracellular enzymes, and rhizosphere colonization). Our research provides the groundwork to design integrated microbial fertilizer products to support enhanced sustainable crop production.

키워드