Insect feeding‐deterrent activity of some saponin glycosides

Saponins and sapogenins isolated from Balanites roxburghii, Agave cantala and Phaseolus vulgaris were studied for insect antifeedant activity against the larvae of the noctuid, Spilosoma obliqua (Walker). The most active compound was diosgenin‐3‐0‐[α‐L‐rhamnopyranosyl (1→2)]‐[β‐D‐glucopyranosyl (1→3)‐β‐D‐glucopyranosyl (1→4)]‐β‐D‐glucopyranoside (X), inhibiting approximately. 73.63 per cent feeding at 0.02 per cent concentration. Relative efficacy of all the tested compounds was assessed, using azadirachtin as standard.