ACTIVITY OF EXTRACTS FROM NONHOST LEGUMES ON THE GERMINATION OF STRIGA-HERMONTHICA SEEDS

Dichloromethane and water extracts from leaves, stems and roots of ten different legume cultivars were assayed for germination stimulation o f moisture and temperature conditioned Striga hermonthica (Del.) Benth . seeds. Optimum concentrations for most active extracts were in the u ndiluted or dilution x 10 range. Unlike water extracts, all dichlorome thane extracts induced some stimulatory activities at the various conc entrations. A potentially high stimulant producing cultivar, V. unguic ulata cv. it-84d-975 was identified. The nondestructive thin-layer chr omatography (TLC) technique was employed in investigating the dichloro methane-soluble substances in legume cultivars. TLC data indicated tha t most legume species and cultivars produce four chromatographically d ifferent germination stimulants with retention factors of 0.10, 0.60, 0.70 and 0.77.