In Vitro Symbiotic Culture Studies of Some Orchid Species

Arzu Çığ,Hüdai Yılmaz

doi:10.15832/ankutbd.385859

Abstract

In this study, protocorm and shoot formation abilities of the seeds of Dactylorhiza iberica (Bieb. ex Willd.) Soo, Dactylorhiza umbrosa (Kar. and Kir.) Nevski and Orchis palustris Jacquin species in binucleic Rhizoctonia and Rhizoctonia solani isolates in vitro, which are used as symbiotic culture medium and isolated from the tubers of these plants, and in oat medium (OM) and modified oat medium (MOM) are examined. The shortest time for protocorm and shoot development of D. umbrosa sowed in oat media are determined as 42.67 and 66 days, respectively. The highest protocorm development rate and the least darkening protocorm percentage are observed as 60 % (OM) and 2.99 % (MOM) in D. umbrosa species. The maximum percentage of shoots obtained from protocorms is observed as 35.04 % in D. iberica species developed in OM. All data were obtained that the inoculation of binucleic Rhizoctonia sp. in the nutrient mediums.

Highlights

Orchid seeds are among the smallest seeds of all flowering plants because they lack endosperm and the embryo is not developed (Mitchell 1989)
A Rhizoctonia solani AG-3 (R) fungal isolate was successfully isolated from a tuber explant of D. umbrosa species cultured on water agar (Figure 1); a binucleate Rhizoctonia (2R) isolate was isolated from tubers of O. palustris species cultured on potato dextrose agar (PDA) (Figure 2)
The differences observed in the present study with respect to protocorm formation from the germinated seeds sown in oat medium and modified oat medium are likely to reflect the combination of agents added to the culture medium

Summary

Introduction

Orchid seeds are among the smallest seeds of all flowering plants because they lack endosperm and the embryo is not developed (Mitchell 1989). Lacking nutrient reserves means that successful orchid seed germination cannot be realized without an external carbohydrate source such as glucose (Ingold & Hudson 1993). All the orchids are obligate mycorrhizal plants and their associations are mostly with Rhizoctonia sp. This association is not species-specific, which means that different orchid species can be infected by the same species of Rhizoctonia (Andersen & Rasmussen 1996). A successful attempt to obtain rootlets in the symbiotic culture of Coelogyne nervosa seeds, an epiphytic orchid species, and Epulorhiza sp. A successful attempt to obtain rootlets in the symbiotic culture of Coelogyne nervosa seeds, an epiphytic orchid species, and Epulorhiza sp. isolate obtained from the Eulophia epidendrea root, a terrestrial orchid, indicates that the relationship between orchids and fungus is not species-specific (Sathiyadash et al 2014)

Methods

Results

Conclusion