Varietal variation in the isoflavone content of subterranean clover: Its estimation by a microtechnique

The isoflavone content of 46 subterranean clover varieties was estimated by a microtechnique which allowed of the semiquantitative analysis of 100 leaf samples per day. The relative proportions of the three major isoflavones varied greatly between varieties. Twenty-four of the varieties tested were low in formononetin. When crushed leaf blade samples were allowed to stand prior to the addition of ethanol there was a decline in detectable genistein. The rate of decline was dependent on the temperature during standing.