Seed germination, seedling growth and haustorial induction in Santalum album, a semi-root parasite

Abstract

Seed germination and early growth of the seedling inSantalum album, a semi-root parasite, is independent of the host but seedling establishment seems to be dependent on the establishment of host contact. About half of the seedlings, raised in aseptic cultures, showed drying of the shoot tip upon transfer to fresh medium and subsequent development of a large number of adventitious shoot buds on the hypocotyl. Attempts to induce rooting in these shoot buds were unsuccessful. Gum tragacanth, which induces haustoria in two Scrophulariaceous root parasites, and xenognosin, the active fraction from gum tragacanth, were effective in inducing haustoria in S. album in the absence of the host.