Rhizome Yield, and Oleoresin and Total Gingerol Content of Ginger (Zingiber officinale Rosc.) Accessions from Southern Ethiopia

Abstract

Knowledge of genetic variability and correlation among agronomic and quality traits is important for plant breeders to improve yield and quality of crops. To evaluate the performance and estimate the variability of ginger accessions, a total of 27 indigenous and 9 introduced accessions were tested at four locations in southern Ethiopia in 2007 using 6 × 6 lattice square designs with three replications. Oleoresin was determined using Sox Tec Extraction and total gingerol content was determined using High Performance Thin Layer Chromatography. The analyses of variance revealed significant (p ≤ 0.05) differences among accessions for most traits studied. The mean fresh rhizome yield was 19.4, 12.2, 10.4 and t ha^-1 at Tepi, Matala Hambecho, Parawocha and Hadaro, respectively. The range of oleoresin extracted with hexane was 2.75-6.25%, and total gingerol content ranged from11.5% to 30.0%. Broad sense heritability (73%) and genetic advance as percent of mean (29.41) were high for fresh rhizome yield. Path coefficient analysis indicated that the superseding componenttraits determining rhizome yield are rhizome length and number of fingers rhizome^-1. Thus, these traits should be given emphasis in improving rhizome yields.