Bioprospecting of citrus (Citrus L.) germplasms against citrus canker pathogenesis in Assam, North‐East India

AbstractThe 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.