Exploration of Vernonia galamensis in Ethiopia, and variation in fatty acid composition of seed oil

Vernonia galamensis is a new potential industrial crop with very high content of vernolic acid in the seed oil. The species is known to naturally grow as a weed in fields or in woodlands under a wide range of agroecological conditions of Africa. In order to study the existing variability in Ethiopia, germplasm collection was carried out. Vernonia grows wild in various ecosystems. Ten regions were explored from North, South, East, Southeast, Southwest and Central Ethiopia. A diverse range of habitats having different altitudes and ecological conditions was explored. Altitude of collecting sites varied between 1250 and 2050 m, and soil pH from 5.1 to 8.5. The most common soil type was sandy loam, and the organic matter content varied from 0.2% to 12.9%. At 80 sites, about 480 accessions were collected including different maturity time, plant type, flower color, and branching patterns as well as fatty acid composition. The mean vernolic acid content of the seed oil of the accessions was 74%, and ranged from 34% to 87%. A wide variability in composition of other fatty acids was observed. It was not possible to find Vernonia in some locations that were earlier indicated by herbarium specimens collected since 1840. This could be a sign of change in land use system and environmental degradation and, hence, loss of genetic resources of the species.