On carbon sequestration efficient clones/genotypes selection for high essential oil yield over environments in Khus (Chrysopogon zizanioides (L.) Roberty)

Abstract Khus/vetiver (Chrysopogon zizanioides (L.) Roberty), family Poaceae, commonly known as khus grass, is important for essential oil used in the perfumery industry as well as in aromatherapy in India, and so is its value world over. The genetic diversity and genotype × environment studies using agronomical traits study in this crop are available. Still, the genotype × environment study using the physiological economic traits is very meager. Therefore, the objectives in the present investigation were to estimate the khus genotypes response over multi-years interaction and the selection of stable high essential oil yielding and carbon sequestration efficient genotypes in the khus. In this study, sixty-five diverse genotypes of khus collected from twenty-five states/places of India and abroad were studied for the seven physiological economic traits in the three consecutive years. The genotypes, environments/years, genotypes × environments/years, years + (genotypes × environments/years), genotype × environments/years (Linn.) related pooled analysis of variance and deviations for the seven characters were found highly significant. This indicates that these genotypes had diverse linear interactions in change environmental conditions. The pooled deviation significances showed that deviation in linear regression contributes towards the genotype’s stability. The predictable/linear or unpredictable/non-linear components significantly contributed to the genotype's stability. Both Eberhart and Russell and GGE biplot analyses identified six promising and stable genotypes for essential oil yield and the three highly stable genotypes for the trait photosynthesis rate. The essential oils of the selected genotypes were also found rich for the major compounds: khusilal, preziza-7(15)-en-12-ol, khusol, and khusimol, along with other minor compounds. The preziza-7(15)-en-12-ol, a prezizaen class of compound, is being reported in high proportions for the first time in Chrysopogon zizanioides (L.) Roberty).