Phenolics play a key role in communication between plants and microbes in the rhizosphere. In this study, shikimic, gallic, fumaric, ferulic, vanillic acid and quercetin in root exudates of Abelmoschus esculentus act as chemoattractants of endophytic Alcaligenes faecalis strains, BHU 12, BHU 16 and BHU M7. In vitro chemotaxis assay showed that BHU 12 expressed highest chemotactic movement (CFU ∼50 × 10¹²) towards A.esculentus root exudates followed by BHU 16 and BHU M7 (CFU∼ 9 × 10¹²), thereby confirming their ability to colonize the host rhizoplane region. However, BHU 16 expressed highest biofilm formation ability followed by BHU 12 and BHU M7. Assessment of chemotactic and biofilm formation potential towards individual phenolic acids revealed BHU 12 to be maximally attracted towards 1 μM shikimic acid (2 × 10¹⁵) while BHU 16 towards 1 mM vanillic acid (6.5 × 10¹²) and BHU M7 towards 1 mM ferulic acid (3.5 × 10¹²), thereby confirming the phenolic acid components responsible for particularly attracting the endophytic isolates. Upon colonization, the endophytic isolates modified the phenolic profiles of root exudates in planta in a manner so as to plausibly attract more of the beneficial rhizospheric microbiota as well as self-fortification against pathogenic microbes. This hypothesis was verified by monitoring the changes in phenolic components of A. esculentus root exudate owing to S. rolfsii infection, a disastrous soil-borne pathogen. Thus, on the whole, the work provides intricate details of plant-endophyte interactions for biotic stress management through careful manipulation of root exudates, thereby aiding in sustainable agriculture.

酚类物质在植物和根际微生物之间的交流中起着关键作用。在这项研究中，莽草酸，没食子酸，富马酸，阿魏酸，香草酸和槲皮素的根分泌物黄蜀葵荸荠充当内生的化学引诱物粪产碱杆菌的菌株，BHU 12，BHU 16和BHU M7。体外趋化性测定表明，BHU 12对菜根根分泌物的趋化运动最高（CFU〜50 ×10 ¹²），其次是BHU 16和BHU M7（CFU〜9×10 ¹²），从而确认它们在宿主根际平面区域定殖的能力。但是，BHU 16表现出最高的生物膜形成能力，其次是BHU 12和BHU M7。对单个酚酸的趋化性和生物膜形成潜能的评估表明，BHU 12被最大吸引至1μMacid草酸（2×10 ¹⁵），而BHU 16被吸引至1 mM香草酸（6.5×10 ¹²），BHU M7被吸引至1 mM阿魏酸酸（3.5×10 ¹²），从而确定酚类成分特别吸引内生分离物。定居后，内生分离物改变了植物根部分泌物的酚类特征以合理的方式吸引更多的有益根际微生物群以及对病原微生物的自我强化。通过监测由于土壤致病性致病菌罗氏链球菌感染而导致的食草曲霉根系分泌物中酚类成分的变化，证实了这一假设。因此，总体而言，这项工作通过对根系分泌物的精心操作，为生物胁迫管理提供了植物-内生菌相互作用的复杂细节，从而有助于可持续农业。