In Vitro Seedlings Growth and Acclimatization of Coelogyne Stricta (D. Don) Schltr. and Coelogyne Flaccida Lindl

Abstract

n vitro seedlings growth of Coelogyne stricta (D. Don) Schltr. and Coelogyne flaccida Lindl., both- epiphytic, ornamental and medicinal orchids, from immature seeds were carried out on Murashige and Skoog (MS) medium with 15 different combinations of 6Benzylaminopurine

(BAP) and α-Naphthalene acetic acid (NAA). MS medium supplemented with BAP (1 mg/l) and NAA (1 mg/l) favoured optimum condition for the seedlings growth of C. stricta while C. flaccida showed best response on MS medium supplemented with BAP (0.5 mg/l) and NAA (0.5 mg/l). Complete plantlets with shoot and root primordia were first observed in the 23 rd week and 22 nd week of culture in C. stricta and C. flaccida respectively. Growth rates with respect to shoot lengths taken after 25 weeks of culture showed significant difference between the two intra-generic species grown under similar conditions of light, temperature and medium. Acclimatization of C. stricta (90%) and C. flaccida (70%) was best observed in coco-peat, sphagnum moss and sand in the ratio of 2:1:1. The present study has provided useful information that nutrient compounds supplemented with hormones are required for the fast growth of in vitro grown seedlings of both species. Keywords: In vitro, Coelogyne stricta, Coelogyne flaccida, MS, BAP, NAA.