STEMFLOW - A SOURCE OF NUTRIENTS IN SOME NATURALLY GROWING EPIPHYTIC ORCHIDS OF THE SIKKIM HIMALAYA

A study on five naturally growing epiphytic orchids viz., Bulbophyllum affine Lindl., Coelogyne ochracea Lindl., Otochilus porrecta Lindl., Cirrhopetalum cornutum Lindl. and C. cornutum (var.) was carried out i n the subtropical belt of Sikkim Himalaya. Stemflow leachates formed t he main source of ammonium-N and nitrate-N for uptake by these orchids . Phosphorus concentration in the tissues of these orchids was high. P hosphate-P from stemflow does not seem to be a regular source of phosp horus for these orchids. Absorption/desorption results indicate that o rganic-N from stemflow leachates is not utilized by these orchids.