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The current investigation assessed the effectiveness of 30 citrus germplasms in combating citrus canker pathogenesis in Assam, North‐East India. Significant differences were observed among the examined citrus germplasms in terms of per cent disease severity and disease reduction against Xanthomonas citri pv. citri. Among the 30 different germplasms, eight germplasms, namely, Jora tenga (14.67%), Bonjora (15.58%), Holong tenga (15.75%), Latipes (17.34%), Patijora (17.75%), Birajora (18.50%), Cleopatra mandarin (20.00%) and Ada jamir (20.18%), exhibited highest disease resistance potential. The study recorded that the germplasm Latipes, which are resistant, had the highest total phenol content (21.26 mg/g dry weight), while the susceptible one, Grapefruit (7.85 mg/g dry weight), had the lowest total phenol content. Jora tenga exhibited the highest flavonoid content, measuring at 6.48 mg/g dry weight, whereas White pummelo had the lowest flavonoid content, measuring at 1.88 mg/g dry weight. Similarly, the highest alkaloid percentage was recorded in resistant germplasm, Adajamir (10.52%), while the lowest was in susceptible germplasm, Volkameriana (2.30%). The levels of total phenol, alkaloid and flavonoid contents exhibited a significant negative correlation with the per cent disease severity of citrus canker disease in both Pearson correlation and Spearmen correlation analysis. The current research on bioprospecting of citrus germplasms in relation to citrus canker pathogenesis has the potential to offer valuable insights into mitigating the transmission of bacterial pathogens and eliminating sources of infection by employing resistant cultivars and implementing approved doses of plant protection formulations. [ABSTRACT FROM AUTHOR]

• The climatic crisis and the emergence of significant pathogenesis are potential threats in agriculture. • The illegitimate application of agrochemicals caused an increase in environmental contaminants and soil quality degradation. • Fluorine-containing imidazolium salts and their metal NHC complexes are emerging antagonistic compounds against significant pathogenesis in agriculture. The current investigation evaluated the in vitro bioefficacy of a newly synthesized unsymmetrical imidazolium salt [1-(2,6-diisopropylphenyl)-3-(2-fluoro-benzyl)-1H-imidazol-3-ium bromide] that contains the electron-withdrawing fluorine atom at the ortho position against agriculturally significant phytopathogens. The molecular structure of the imidazolium salt was characterized by various spectroscopic techniques such as 1H, 13C, and 19F NMR, FTIR, and high-resolution mass spectrometry (HRMS). Antimicrobial bioassay of the compound has been tested against two Gram-negative, bacterial phytopathogens namely Ralstonia solanacearum (Rs) (Gen Bank accession no. OQ743450) [causal agent: bacterial wilt of solanaceous crops], and Xanthomonas citri pv. citri (Xcc) (Gen Bank accession no. OR7036310) [causal agent: citrus canker in citrus trees] and two fungal phytopathogens namely Fusarium solani (Gen Bank accession no. OR140825) [causal agent: Fusarium die-back in tea] and Pseudopestalotiopsis chinensis (Gen Bank accession no. OR140826) [causal agent: grey blight in tea]. Different concentrations of imidazolium salt was tested against the target phytopathogens using the in vitro antimicrobial bioassay through disc diffusion method. The imidazolium salt demonstrated a maximum percentage inhibition of 16.70 and 21.78 against the bacterial phytopathogens R. solanacearum, and X. citri pv. citri , respectively, at a concentration of 2000 ppm over negative control. Similarly, the compound demonstrated promising antagonism against the tea fungal pathogens F. solani and P. chinensis (percentage inhibition up to 61.43 and 80.84, respectively at 2000 ppm) over negative control. Five replications were maintained in each of the cases. The present investigation demonstrated the potential of fluorinated imidazolium salt as commercial antimicrobial agent in integrated disease management schedule to control significant phytopathogenesis in agriculture including in tea. [Display omitted] [ABSTRACT FROM AUTHOR]