Effect of different substrates on in vitro symbiotic seed germination for soilless production of Anacamptis laxiflora orchid

Abstract

In recent years, orchid species have become endangered due to excessive collection and habitat destruction. As with most flowering plants, seed production is the primary strategy for reproduction in orchids. Orchids produce tiny seeds consisting of a seed coat and a rudimentary embryo. However, it lacks the endosperm, which is generally required as the primary energy source during germination. The only way to germinate orchid seeds is to get nutrients from an external source. In nature, this is achieved by mycorrhizal symbiosis. This study used Ceratobasidium sp. inoculation of Anacamptis laxiflora (Lam.) seeds combined with media with various organic substrates to determine their effectiveness on in vitro germination and seedling development. The highest germination rate (35.78%) was obtained in the medium with the addition of young hazelnut leaves. Then, soilless ex vitro symbiotic germination was performed on young hazelnut leaves, the most effective organic substrate. Seed germination was determined to be 19.01% in this medium while 14.87% seedlings with developed leaves and roots were formed. For the first time, success was achieved by producing A. laxiflora from seed in ex vitro conditions without soil and adapting it to nature.