Collecting near mature and immature orchid seeds for ex situ conservation: ‘in vitro collecting’ as a case study

Abstract

BackgroundLack of phenological information and efficient collecting methods are considered impediments for orchid seed collecting. This leads to opportunistic collecting as part of general seed collecting schedules that may last few weeks especially in remote areas. The study explored the feasibility of collecting near mature and immature seeds to support conservation action plans. Mature, near mature and immature seeds of orchids were collected from the wild in the Central Highlands of Madagascar (CHM). Seed capsules were collected in sterile culture medium in the wild, to prevent deterioration of seeds inside the capsule after collecting, later to be cultured under laboratory conditions.ResultsSeed capsules collected by the in vitro collecting (IVC) method were kept in very good condition for up to 4 weeks before germination under in vitro conditions. Significantly faster and higher germination rate (p < 0.001) than mature seeds was observed in a number of taxa collected during a 3 year-long study. In some taxa even immature seeds, with no apparent sign of testa covering the embryo, germinated following IVC where mature seeds failed to germinate.ConclusionsWe propose that IVC method has potential to complement conventional seed collecting by increasing the germplasm that can be used in integrated conservation action plans. Improvements can be made in developing collections for taxa from biodiversity hotspots and remote areas where collecting requires considerable resources. This method can further be used on a wider selection of plants from different geographic areas and on embryo rescue programmes for economically important plants.Electronic supplementary materialThe online version of this article (doi:10.1186/s40529-017-0187-5) contains supplementary material, which is available to authorized users.

Recovery of mycorrhizal fungi from wild collected protocorms of Madagascan endemic orchid Aerangis ellisii (B.S. Williams) Schltr. and their use in seed germination in vitro

“…The seeds used were collected at site 2 (Fig. 2 ) from a mature, nearly dehiscent capsule from a natural population within the CHM during a previous trip (Kendon et al 2017 ). Capsules were collected and stored in paper envelopes inside a Ziplock bag containing silica gel beads as a desiccant.…”

“…hawkmoths) may be less common and/or they must fly considerable distances to forage on nectar, possibly explaining why few capsules are produced among the species that cater to moths (e.g. Aerangis , Angraecum ), and why a high proportion of their seeds often lack embryos (Kendon et al 2017 ). Thus, with limited cross-pollination, fewer spontaneous seedlings are generated per year resulting in steady population decline over time.…”

Orchid conservation: how can we meet the challenges in the twenty-first century?

“…Meeting these challenges will in many cases also involve a combination of creating new habitats, transplantation and ex situ conservation in seedbanks and living collections. Papers in this issue by Kendon et al ( 2017 ), Zettler et al ( 2017 ) and Higaki et al ( 2017 ) focus on some aspects of ex situ conservation.…”

Establishment of Reciprocal Micrografting of Tomato (Solanum lycopersicum L.) and Eggplant (Solanum melongena L.)

“…Moreover, seed sterilization is often easier and seeds are considered free from some diseases such as bacteria or even some viruses. Since 0.1% HgCl2 has been used to sterilize tomato seeds for 5 min (Zhang et al, 2012), and sodium dichloroisocyanurate (active component of Presept) is known to be less toxic to explants and therefore can be used at a wide range of concentrations (0.5-2.0%) for different periods of time (from 5-90 min) (Mihaljević et al, 2013;Kendon et al, 2017), we decided to use both 0.1% HgCl2 and 0.5% Presept for sterilization.…”