A Modified Approach for Axenic Cultivation of Spores of Fern Adiantum capillus-veneris L. with High Germination Rate

Background

In the phylogenetic tree of plants, ferns are a critical clade of land plants, as they are the sister lineage of seed plants. Ferns are characteristic by their unique life cycle. Compared with seed plants, the sporophyte of ferns bear spores for spreading instead of seeds. Under favorable conditions, spores germinate to form gametophytes, in which cells on certain areas (rib) specialize into reproductive organs to produce gametes. After water-dependent fertilization, the newborn sporophyte emerge and an entire life cycle of fern completes (Li et al., 2013). Hence, to study the sexual reproduction processes and life history of ferns, spore cultivation under experimental conditions is necessary.

However, protocols available for ferns spores cultivation are insufficient. Here, we choose Adiantum capillus-veneris L. as experimental material to optimize the spore cultivation protocol, as Adiantum is a representative fern with isospory, and the cultivation system of Adiantum under lab condition has been developed by Li et al. (2013).

This protocol is also instructive for spore cultivation in other members of homosporous ferns.