IRONWEED

Family: Compositae

Genus: Vernonia

Species: anthelmintica

galamensis

pauciflora

(i) General background on the plant

Two species of Vernonia have been examined as potential sources of epoxy oils.

V. anthelmintica, an Indian annual plant has up to 40% oil in seed and up to 75% vernolic acid in oil. Unfortunately it is still an under-developed species and has exhibited pod severe shatter and seed loss problems in US trials. For that reason the experimental programme on it was terminated. Lately there has been much more interest in an East African species, V. galamensis. In some literature this species is recorded as V. pauciflora. The two names are synonymous. It is grown as a commercial crop in Zimbabwe. V. galamensis appears to be a short day length, annual plant.

(ii) Details of quality characters

Systematically, vernolic acid is 12,13-epoxy-cis-9-octadecanoic acid. The fatty acid profile of V. galamensis oil as reported by Ayorinde et al (1990) is:

FATTY ACID

% IN OIL

Vernolic

79-81

Linoleic (C18:2)

11-12

Oleic (C18:1)

4-6

Stearic (C18:0)

2-3

Palmitic (C16:0)

2-4

Oil content of seed is approximately 40% by weight.

(iii) Current production and yields

Vernonia is produced on a limited scale commercially in Zimbabwe, Kenya and Pakistan. Old world species are distributed in India and Africa.

No European data on this crop has been found in the European situation hence there is presumed to be no production.

(iv) Constraints on production

Currently the growing season in northern Europe is too short and plants fail to flower and produce seed before frost. (Senft, 1994)

(v) Markets and market potential

Vernonia species are considered as economic crops because of their potential to produce vernolic acid, an epoxy acid with uses as a dilutent in alkyd-resin paints, in plasticisers, adhesives, synthetic fibres/plastics.

(vi) Other information

Germplasm of Vernonia have been selected that are neutral to day length, and therefore suitable for the development of a temperate industrial crop.

(vii) Contacts

(viii) References

Askew, M. F. (1992). A review of novel oilseeds & fibre crops and their potential for the UK. ADAS Wolverhampton, Woodthorne, Wergs Road Wolverhampton, WV6 8TQ.

Ayorinde, F.O. et al (1990). Vernonia galamensis: a Rich Source of Epoxy Acids. J. Amer Oil Chem. Soc. 67, 844.

Senft, D. 1994. Agricultural Research/September 1994