Biplot analysis in advanced generation lines for the nutritional quality of leaves and essential oil yield in vetiver (Chrysopogon zizanioides L. Roberty)

The vetiver is an excellent source for essential oil, fodder, thatching, handicrafts, and mulching. Besides its various utility, a limited study has been done as fodder for ruminants. The major studies in the vetiver were focused on oil production, soil/water conservation. The study related to livestock cattle feeding on vetiver is very meager. The essential oil content, yield, nutritional, and protein quality of the fodder are highly affected by the G × E interaction. Objectives were to determine the extent of genotype × environment interaction for the nutritional quality of fodder, oil yield and to identify stable genotypes for the future breeding program. The thirty lines were evaluated to meet the above objectives to select genotypes with high oil yield and fodder quality. The genotypes were planted in RBD at the Institute in three years. The observations were recorded on twenty traits. The roots were distilled for oil by hydro-distillation for 24 h. GC analysis was performed in a Varian CP 3800 system using an Elite-5 fused silica column (30 m × 0.25 mm × 0.25 μm). The pooled mean observations of all characters were analyzed for stability by the GGE biplot. For after the pooled ANOVA across years, all the twenty traits showed highly significant variations except four. Except for one variable, essential oil content, genotype was very significant for all twenty traits (%). For maturity stage × year interaction, all the twenty traits also showed high significance except four traits. For the maturity stage × genotypes interaction, all the twenty traits also showed highly significant variations except four traits. For years × genotypes interaction, all twenty traits also showed highly significant differences. For the maturity stage× years × genotypes interaction, all the twenty traits also showed high significance except one trait. The genotype Vg-11/selection 24 expressed the highest performance for eight traits: digestibility, protein, potassium, phosphorus (%), iron, copper, and manganese (mg/Kg) in vetiver leaves and the root yield/plot (g). The genotype Vg-15 for the three traits: calcium (%), khusinol, and β-vetivone (%) in essential oil. Despite the importance of essential oil, its leaves are vital due to their nutritional quality and can be used as fodder. Genotype Vg-11/selection 24 may recommend as a suitable and nutritious fodder and Vg-13 for high oil. The vetiver also has a perfect opportunity to be as nutritious fodder in livestock for nutrition and production.