Stress tolerance of Xerocomus badius and its promotion effect on seed germination and seedling growth of annual ryegrass under salt and drought stresses

Binghua Liu,Xinghong Liu,Fangchun Liu,Bingyao Ma,Hailin Ma,Lin Peng

doi:10.1186/s13568-020-01172-7

Abstract

Comparative evaluations were conducted to assess the effects of different pH levels, NaCl-induced salt stress, and PEG-induced drought stress on the mycelial growth of Xerocomus badius. The results showed that X. badius mycelium grew well at a wide pH range of 5.00 ~ 9.00. Although the mycelium remained viable, mycelial growth of X. badius was significantly inhibited with increasing salt and drought stresses. Furthermore, a soilless experiment in Petri dishes was performed to investigate the potential of X. badius to induce beneficial effects on seed germination and seedling growth of annual ryegrass (Lolium multiflorum Lam.) under salt and drought stresses. Seed priming with X. badius enhanced the seedling growth of L. multiflorum Lam. under NaCl-induced salt stress and PEG-induced drought stress. However, X. badius did not significantly improve the seed germination under non-stress and mild stress conditions. It suggested that X. badius inoculation with seeds was not essential for seed germination under non-stress and mild stress conditions, but contributed highly to seedling growth under severe stress conditions. Therefore, seed priming with X. badius on ryegrass could be an effective approach to enhance plant tolerance against drought and salt stresses. X. badius could be a good candidate for the inoculation of ectomycorrhizal plants cultivation programs in mild saline and semiarid areas.

Highlights

Abiotic and biotic stresses influence plant growth, survival and productivity
Based on the findings from the tolerance test with X. badius and the verified mutualistic symbiosis between Lolium multiflorum Lam. and X. badius driven by seed inoculation (Liu et al 2019), we propose that X. badius is expected to enhance stress tolerance of L. multiflorum Lam. under drought and salt stresses
Expr (2021) 11:15Ectomycorrhizal (ECM) fungi can grow under conditions from acidic to slight alkaline (Zhu et al 2008; Siri-in et al 2014), but each fungal species has its optimum pH level for mycelial growth (Lazarević et al 2016)

Summary

Introduction

Abiotic and biotic stresses influence plant growth, survival and productivity. Drought and high salinity are the two most important environmental factors that negatively affect seed germination, seedling growth and development, and influence crop yield, food quality and global food security. Application of stress tolerant plant growth promoting fungi (PGPF) may enhance crop seed germination, seedling establishment, plant growth, and productivity under adverse environmental. Mycorrhizal fungi play an increasing vitally important role in host plants growth promotion, in inducing plant stress tolerance and agricultural sustainability under various environmental stress conditions (Behie and Bidochka 2014; Bonfante and Genre 2010; Courty et al 2010; Garcia et al 2016; Hossain et al 2017; Javeria et al 2017; Shen et al 2018; Yan et al 2019). In order to develop controlled ectomycorrhization practices that are suitable for the inoculation of field plants and are efficient in promoting host plants’ growth under specific environmental conditions, it is necessary to isolate potential ECM fungi and evaluate their biological, physiological and symbiotic characteristics, as well as the specificity that they have with certain hosts, under the controlled laboratory conditions

Methods

Results

Conclusion