2nd Edition of Agriculture, Forestry, and Horticulture World Conference 2026

Abstract

An investigation was carried out in black turmeric (Curcuma caesia Roxb.) genotypes during 2024-2025 to study the morphological variation based on DUS guidelines, extent of genetic variability, association among different characters, direct and indirect effects on yield components, variation in quality traits, metabolite profiling of  essential oil, camphor quantification and molecular docking studies for bioactive  compounds in 21 black turmeric genotypes across two locations - Coimbatore and Bhavanisagar. The comparison of the mean performance of 21 genotypes for thirteen traits using critical differences revealed the existence of a high level of variability. The genotypes GMN-10, GND-11, GKK-6 and GTE-18 registered the highest yield across the environments. GMN-10 and GND-11 performed well in the Bhavanisagar location with rhizome yield per plot of 1.92 kg each. At Coimbatore location, GMS-7, GKY-14 and GMU-21 performed well in terms of yield with 0.92 kg, 0.90 kg and 0.89 kg per plot respectively. Based on per se performance for individual rhizome weight, GMN-10 recorded 87.68 g, GKY-14 recorded 76.53 g and GKK-6 recorded 69.83 g based on pooled data. GKK-6 recorded significantly  less days to maturity with 238.85 days. Essential oil was found significantly high in GTE- 18 (0.51%), GMN-10 (0.46%) and GMR-2 (0.43%). The genotype GCA-5 recorded the highest total phenolic content (3.35 mg/g), GOB-19 exhibited maximum total flavonoid content (32.32 mg/g), GTE-18 recorded the highest total protein content (144.26 mg/g), highest alkaloid content (208.44 mg/g) and highest cardiac glycoside content (173.93 mg/g) based on pooled data. The rhizome yield per plot revealed a positive and highly significant association with leaf length (1.489), essential oil content (1.276), plant height (1.055) and girth of rhizome (0.465) in genotypic correlation. In phenotypic correlation, rhizome yield per plot showed significant positive correlation with weight of rhizome per plant (0.588), number of tillers (0.452) and length of rhizome (0.305). Mahalanobis D² analysis based on 13 parameters classified 21 genotypes into six clusters. Among the six clusters, the maximum intra cluster distance was observed in Cluster I (32.95) and the maximum inter cluster distance was observed between Cluster III and IV (260.45). The plant height contributed to maximum divergence (20.42%), followed by number of rhizomes per plant (18.70%), essential oil (15.60%), length of rhizome (15.07%) and weight of rhizomes per plant (9.31%). The same set of genotypes were profiled using 16 ISSR primers. Primer UBC 861 recorded the maximum PIC value (0.44), followed by UBC 809 (0.40) and UBC 866 (0.37).  The percent polymorphism was the highest for primers UBC 808 (95.24%), UBC 810 and UBC 891 (90.48%). Thirty different compounds were identified from ginger essential oil through GCMS profiling. Camphor, epicurzerenone, curzerene, longiverbenone, ageratriol, isoborneol, humulene epoxide, guaidiol, caryophyllene oxide, carveol and ledol were detected in one or other genotypes. Camphor was a major constituent in all the genotypes which ranged from 0.51% (GKK-6) to 20.91% (GMR-2). Epicurzerenone ranged from 7.17% (GMN-10) to 56.44% (GKK-6). Curzerene ranged from 3.53% (GRU-4) to 13.12% (GKK-6). GC-MS/MS quantification of camphor revealed substantial genotypic variation ranging from 5.19% in GKK-6 to 33.84% in GTE-18, representing 6.5-fold difference. High-camphor genotypes included GTE-18 (33.84%), GMR-2 (30.35%), GMN-10 (26.41%), GCA-5 (24.44%), GRU-4 (23.32%), GKY-14 (22.18%) and GAP-8 (21.78%). Low-camphor genotypes included GAN-16 (5.20%) and GKK-6 (5.19%). Molecular docking studies revealed that camphor exhibited the highest binding affinity with 1ITV receptor (-7.8 kcal/mol) compared to the standard drug Ranitidine (-6.3 kcal/mol). Curzerene showed the highest binding affinity with 5FXQ (-6.8 kcal/mol) and 1 WT5 (-7.1 kcal/mol). Molecular dynamics simulation of MMP9-camphor complex over 100 ns confirmed structural stability with RMSD values between 0.20-0.25 nm, indicating that camphor remains stably bound within the MMP9 binding pocket with gastric ulcer treatment properties.

Keywords: Molecular, Biochemical Characterization, Black Turmeric, Different Environment