Partitioning of Fungal Endophyte Assemblages in Root-Parasitic Plant Cynomorium songaricum and Its Host Nitraria tangutorum

Abstract

Endophytic fungi are an integral part and even seen as host organs of plant, influencing physiology, ecology, and development of host plants. However, little is known about micro-ecosystems and functional interactions of endophytic fungi in root-parasitic interactions of Cynomorium songaricum and its host Nitraria tangutorum. Here, distribution and dynamics of endophytic fungi were objectively investigated in their associations with C. songaricum and N. tangutorum based on mycobiome studies using high-throughput sequencing. Results suggest that endophytic fungi may be exchanged between C. songaricum and its host N. tangutorum probably through haustorium, connection of xylem and phloem in the vascular system. The similarity of endophytic fungal composition between C. songaricum and parasitized N. tangutorum was 3.88% which was significantly higher than the fungal similarity of 0.10% observed between C. songaricum and non-parasitized N. tangutorum. The similarities of fungal community in parasitized N. tangutorum were much closer to C. songaricum than to the non-parasitized N. tangutorum. The composition of endophytic fungi in these associations increased in progressive developmental stages of C. songaricum from sprouting to above ground emergence, and decreased subsequently probably due to host recognition and response by fungi. However, the shared fungal operational taxonomic units (OTUs) increased among interactions of C. songaricum with parasitized and non-parasitized N. tangutorum. Studies of bioactivity on culturable endophytic fungi showed that isolates such as Fusarium spp. possess the ability to promote seed germination of C. songaricum. Our study reports for the first time the special ecological system of endophytic fungi in C. songaricum and its host N. tangutorum. Overall, we hypothesize that a deeper understanding of the sharing, movement, and role of endophytic fungi between root-parasitic plant and its host may lead to finding alternative approaches to help increase the output of ethno-pharmacologically important medicinal plants.

Bioprospecting endophytic fungi from Fusarium genus as sources of bioactive metabolites

“…from the root of Dendrobium moniliforme was able to promote the growth and development of Rhynchostylis retusa. This supported the finding of Cui et al (2018) who reported earlier the ability of three endophytes isolates of F. redolens KY379544, F. nematophilum KY379572 and F. nematophilum KY379764 to promote the germination of C. songaricum seeds. Moreover, metabolites produced by several Fusarium spp.…”

Differences in the endophytic fungal community and effective ingredients in root of three Glycyrrhiza species in Xinjiang, China

“…The samples from the final rinse solution were cultured using the potato dextrose agar (PDA) plate for 72 h at 28 °C. No fungal growth was observed on the PDA media, which suggested that root samples were effectively surface-sterilized (( Cui Vinod & Gang, 2018 )). All root samples were labeled and immediately placed on ice and stored at liquid nitrogen until total DNA extraction.…”

Parasitic Plants as Vectors for Pathogens

“…Besides bacterial communities, endophytic fungi also inhabit the inner tissues of parasitic plants. For instance, the rootparasitic plant Cynomorium songaricum parasitise Nitraria tangutorum, a flowering shrub from the Nitrariaceae family, harbours several fungal species assemblages belonging to the phylum, Ascomycota, Basidiomycota and Zygomycota [67]. Microbial communities play diverse roles during the growth and development and parasitism of parasitic plants on their host plants.…”

“…Microbial communities play diverse roles during the growth and development and parasitism of parasitic plants on their host plants. For instance, some species of the genus, Fusarium, promote parasite seed germination, while symbiosis of arbuscular mycorrhizal fungi (Glomus mosseae) and rhizobia can alleviate plant host damage by root hemiparasites [67,68]. Nitrogen-fixing bacteria associated with host plants may indirectly benefit parasitic plants through efficient N 2 -fixation and their availability to the parasite during host attachment [69,70].…”