Isolation and identification of beneficial orchid mycorrhizal fungi in Paphiopedilum barbigerum (Orchidaceae)

Abstract

Seed germination and seedling development in nearly all orchid species rely on a symbiotic relationship with mycorrhizal fungi; however, this is not the case with all mycorrhizal fungi. This study aims to provide an understanding about the important role of mycorrhiza in seed germination and growth of Paphiopedilum barbigerum . Therefore, we isolated and identified endophytic fungi from the roots of wild P. barbigerum . The beneficial mycorrhizal fungi Epulorhiza sp. FQXY019 and Tulasnella calospora FQXY017 were screened by seed symbiotic germination tests and found to promote seed germination. However, only the seeds inoculated with FQXY019 progressed from the seed germination to rooting stage. This shows that mycorrhizal fungi and P. barbigerum have a specific relation at different growth phases. In addition, we selected FQXY019 and inoculated it into MS medium, B5 medium, OMA medium, and PDA medium. The results showed that FQXY019 co-cultured on PDA significantly promoted the increase in seedling fresh weight, leaf length, and root length ( p < .01). Furthermore, it significantly promoted the root number and leaf number of seedlings compared with those co-cultured on MS, B5, and OMA media and control ( p < .05). Thus, this study demonstrated the promoting effect of Epulorhiza sp. FQXY019 on seed germination and seedling development, making it an alternative method for the artificial propagation of P. barbigerum.

Comparative transcriptomics and proteomics analysis of the symbiotic germination of Paphiopedilum barbigerum with Epulorhiza sp. FQXY019

“…Epulorhiza sp. FQXY019 had been isolated from the mycorrhizal roots of P. barbigerum in our previous study ( Tian et al, 2022 ). First, a layer of cellophane was placed onto 9 cm Petri dishes containing 30 mL potato dextrose agar (PDA) medium (200 g potato, 10 g agar, 20 g glucose, and 1 L distilled water).…”

“…Herein, we investigated the germination of P. barbigerum, a rare Paphiopedilum native to southwest China with high ornamental value, in the presence of a mycorrhizal fungus, Epulorhiza sp. FQXY019, which we had previously isolated and which progressed seed germination of P. barbigerum ( Tian et al, 2022 ). Based on this, we integrated transcriptomics analyses with proteomic techniques to investigate the genes and proteins differentially expressed in the seed germination of P. barbigerum with and without Epulorhiza sp.…”

High endophytic diversity associated with roots of Cattleya milleri, an endemic orchid from rupestrian grasslands of the “Quadrilátero Ferrífero”, a Brazilian savanna hotspot area in Minas Gerais

“…Thus, their inoculation is suitable during plant cultivation, especially during the propagation of the species toward reintroduction (Cribb et al 2003;Nogueira et al 2005;Li et al 2021b). Once an orchid is reintroduced in nature with endophytes, both the plant and its symbionts are preserved and reintroduced, which increases the chances of occurrence of natural propagation and the maintenance of the orchid life cycle (Cribb et al 2003 Implementing symbiotic propagation requires culture-dependent studies, where endophytic fungi are isolated, classi ed, and then, used in a co-inoculation test to select appropriate isolates for orchid propagation Valadares 2012, 2017;Tian et al 2021). Although fungal isolation has been an important source of information about orchid mycorrhizal root endophytes (Pereira and Valadares 2017;Li et al 2021a), culture-independent studies are performed using next-generation sequence (NGS) platforms, which improve knowledge about root fungal community (Waud et al 2016;Li et al 2021a), provide broad information about the most important fungal endophytes on orchid roots and so as give support during the selection of appropriate fungal isolates to be applied in further orchid propagation programs.…”

Characterization of a Plant Growth-Promoting Endohyphal Bacillus subtilis in Fusarium acuminatum from Spiranthes sinensis

“…The endophytes in orchids are mostly specific fungi of Basidiomycota, such as Sebacinaceae, Ceratobasidiaceae, and Tulasnellaceae ( Zettler and Corey 2018 ; Li et al 2021 ; Wang et al 2021 ). In addition, some endophytes from the root, especially Fusarium (Ascomycota), are thought to form mycorrhizae with orchids ( Tian et al 2022 ). Chen et al (2010) found that Fusarium is the dominant endophytic fungi in the medicinal orchid Dendrobium loddigesii and could improve its growth rate and biomass.…”