Green Globular Body Induction and Plantlet Regeneration of Endangered Fern Adiantum reniforme var. sinense

Abstract

Background: Adiantum reniforme var. sinense is a pteridophyte with considerable ornamental importance and medicinal value. However, the wild population of A. reniforme var. sinense has gradually become scarce due to sparse distribution and human activities. Green Globular Bodies (GGBs) are specific tissue which use to propagate ferns in vitro. The study uses GGBs induced from sporophytic embryos to preserve and to proliferate this pteridophyte. Methods: The present study was carried out during year 2018-2020 at National Ilan University. The developing sporophyte of Adiantum reniforme var. sinense were used to induce GGBs. The optimal medium for GGBs proliferation and differentiation in terms of basal salts, plant growth regulators, sugar concentrations and gelling agents was examined. The structure of GGBs and the embryos were analyzed by paraffin section as well. Result: The result indicates the 100% GGBs induction rate from sporophytic embryos for the first time could be obtained under BA (0.1 mg L-1) and NAA (0.15 mg L-1). For subsequent proliferation of GGBs required a higher concentration of NAA (10 mg L-1). Cytokinins such BA, KT and TDZ, inhibited GGBs proliferation. In vitro optimal amount of basal salts, plant growth regulators, sugar concentrations and gelling agents for GGB proliferation were obtained as 2 g L-1 Hyponex, 10 mg L-1 NAA, 15 g L-1 sucrose and 4 g L-1 gelrite, respectively. Paraffin sections revealed histological characteristics of the sporophytic embryo and GGB.