Isolation and Characterization of Endomycorrhizal Fungi Associated with Growth Promotion of Blueberry Plants.

Binbin Cai,Wenru Yang,Wenrong Chen,Yunying Fang,Tony Vancov,Hanqi Si,Kunning Tong

doi:10.3390/jof7080584

Abstract

Despite their notable root mutualism with blueberries (Vaccinium spp.), studies related to Ericoid mycorrhizal (ERM) are relatively limited. In this study, we report the isolation of 14 endomycorrhizal fungi and their identification by fungal colony morphology characterization combined with PCR-amplified fungal internal transcribed spacer (ITS) sequence analyses. Six of the isolated strains were confirmed as beneficial mycorrhizal fungi for blueberry plants following inoculation. We observed the formation of typical ERM hyphae coil structures—which promote and nutritionally support growth—in blueberry seedlings and significant nitrogen and phosphorous content increases in diverse tissues. QRT-PCRs confirmed changes in VcPHT1s expression patterns. After the formation of ERM, PHT1-1 transcription in roots was upregulated by 1.4- to threefold, whilst expression of PHT1-3 and PHT1-4 in roots were downregulated 72% and 60%, respectively. Amino acid sequence analysis of all four VcPHT1s genes from the blueberry variety “Sharpblue” revealed an overall structural similarity of 67% and predicted transmembrane domains. Cloning and overexpression of PHT1-1 and PHT1-3 genes in transgenic Arabidopsis thaliana plants significantly enriched total phosphorus and chlorophyll content, confirming that PHT1-1 and PHT1-3 gene functions are associated with the transport and absorption of phosphorus.

Highlights

College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China; Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China
According to internal transcribed spacer (ITS) sequencing, 13 species belonged to Ascomycota, and 1 species (X5) was unknown but considered as an endomycorrhizal fungus due to its morphology
Felted or in a flocculent formation, white to off-white in color with smooth margins, while a minority showed a radial pattern, secreted pink, yellow or green pigments (Figure 1A)

Summary

Introduction

College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China; Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China. Despite their notable root mutualism with blueberries (Vaccinium spp.), studies related to Ericoid mycorrhizal (ERM) are relatively limited. Six of the isolated strains were confirmed as beneficial mycorrhizal fungi for blueberry plants following inoculation. Phosphorus transport pathways: one that directly absorbs via the root surface and root hairs in the soil interface, and the other absorbs by means of the hyphae in soil [7]. Phosphorus transport proteins are quintessential in mediating uptake

Methods

Results

Conclusion