EFFECT OF COCONUT WATER AND ACTIVATED CHARCOAL ON SEED GERMINATION IN AN ENDEMIC ORCHID RHYNCHOSTYLIS RETUSA BLUME.

Nisha Raj S

doi:10.26524/krj215

Abstract

The present study on in vitro seed germination of Rhynchostylis retusa obtained on nutrient medium made clear pathway for the in vitro propagation of orchids by seed culture. The presence of coconut water in the medium enhanced seed germination and growth of seedlings. For enhancing the growth of seedlings further the individual seedlings were cultured on MS medium supplemented with 3 mg/l BAP and 1g/l activated charcoal. These seedlings were sub cultured on rooting medium (IBA) supplemented with activated charcoal. The plantlets were transferred to soil with 90% success. Hence the present investigation made possible for the large scale multiplication of R.retusa and thus to conserve this endemic orchid.

Highlights

In vitro culture of orchids is of much importance since the percentage germination in nature is extremely low
The present study on in vitro seed germination of Rhynchostylis retusa obtained on nutrient medium made clear pathway for the in vitro propagation of orchids by seed culture
For enhancing the growth of seedlings further the individual seedlings were cultured on MS medium supplemented with 3 mg/l BAP and 1g/l activated charcoal

Summary

INTRODUCTION

In vitro culture of orchids is of much importance since the percentage germination in nature is extremely low. Two fundamental types of embryo development occur in Orchidaceae. They are: (1) Zygote divides to form an undifferentiated mass of cells from where the suspensor cells are formed earlier and filamentous proembryo. Formation of orchid seedling from the seeds involves 3 sub sequential phases namely germination, protocorm formation and seedling development (Mitra, 1976). First visible sign of germination is the swelling of embryo followed by their turning green and emergence of the breasted seed coats This is called the spherical stage which subsequently develops into protocorm stage and later into the swelling stage (Mitra, 1976). The in vitro culture of orchid seeds reveals that the seeds obtained from green pod 8-12 weeks of anthesis, germinate readily in a large number of species. Shoot multiplication can be achieved in small space because miniature plantlets are produced

Preparation of the media

Preparation of the explant and inoculation

Germination rooting and transfer of the plant

RESULTS AND DISCUSSION