Variation in coumarin concentration between lines of Melilotus sp.

Abstract

Sweet clover (Melilotus sp.) has recently been identified in Australia as a pasture legume potentially suited to saline land. Some Melilotus species have shown high herbage productivity under such conditions. However, Melilotus can contain high levels of coumarin that can be converted to dicoumarol upon fungal contamination (Sanderson et al. 1986). Dicoumarol is an anti-coagulant and is the cause of sweet clover poisoning in stock fed spoiled Melilotus hay (Yamini et al. 1995). Leaf tissue from 93 Melilotus lines, sampled when 90% of the plants were flowering, was freeze dried, ground, extracted using methanol at 35�C under vacuum and analysed for coumarin concentration using HPLC.