Rhizoctonia repens

The compounds orcinol (20) and hircinol (21) are phytoalexins in Orchis militaris and in other species of Orchis (Orchidaceae) when infected with Rhizoctonia repens (Brooks and Watson, 1985 Coxon, 1982 Dewick, 1984 Kuc, 1992). These compounds are active as phytoalexins against a range of organisms at 10 " M (Gorham, 1989). Hircinol has also been isolated from tubers of yam (Diosc-orea rotundata, Dioscoreaceae) where it is a preformed antifungal compound. 

Orchinol 9,10-dihydro-2,4-dimethoxy-7-phenan-throl, a phytoalexin. O. is formed by the orchid Orchis militaris as a defense against infection by the fungus Rhizoctonia repens. The structurally related... 

Archer AW, Elix JA (1992) Further new species and new reports of Pertusaria (lichenised Ascomycotina) from Australia. Mycotaxon XLV 417-431 Archer AW, Taylor WC (1987) Homoheveadride, a cyclononadiene bis-anhydride from Cladonia poly-carpoides. Phytochemistry 26 2117-2119 Arditti J, Fisch REMH, Flick BH (1972) Ergosterol peroxide from Rhizoctonia repens composition, conformation and origin. J Chem Soc Chem Comm 1217-1218 Armaleo D (1993) Why do lichens make secondary products XV Int Bot Congr, Tokyo-Yokohama, Abstr, 11 pp... 

---