EFFECT OF BASAL MEDIUM AND PLANT GROWTH REGULATORS ON SEED GERMINATION, DIFFERENTIATION AND SHOOT REGENERATION OF PAPHIOPEDILUM CONCOLOR (LINDL.) PFITZ

Abstract

Paphiopedilum concolor (Lindl.) Pfitz is a native species of Northern Vietnam. Recently, this species has been extremely exploited in nature due to deforestation  and over-collection, so it is essential to develop in vitro propagation methods for conservation. This paper represent that we have successfully studied a number of factors affecting the efficiency of propagation of Paphiopedilum concolor by in virto seed germination, including suitable mineral medium for seed germination, suitable media added plant growth regulators for differentiation and shoot formation, a suitable medium for shoot regeneration and seedding growth. Seeds were  cultured on ½ MS or ½ VW medium gave high germination rates (82.5% and 80%, respectively), germination time was 37.5 to 40 days. The suitable medium for the differentiation and development of germinated seeds was P5 medium (VW + BAP 1.0 mg/L, NAA 0.5 mg/L, banana homogenate 30 g/L, potato homogenate 40 g/L) with the highest percentage of shoot formation (50.1%). The suitable medium for shoot regeneration and seedling growth was VW medium supplemented with BAP 2.0 mg/L, NAA 0.5 mg/L, number of shoots/sample reached 2.0, number of leaves/shoot reached 3.5, leaf length reaches 1.35 cm, seeddings with large, dark green and thick leaves. These results are basis for further studies on in vitro propagation of P. concolor in Vietnam.