Scrutinizing the Application of Saline Endophyte to Enhance Salt Tolerance in Rice and Maize Plants.

Zamin Shaheed Siddiqui,Daniel Anthony Dias,Asma Hanif,Shahnaz Dawar,Muhammad Umar,Zainul Abideen,Roomana Yasmeen,Faisal Zulfiqar,Xiangying Wei,Jianjun Chen

doi:10.3389/fpls.2021.770084

Abstract

The present study aimed to witness the plant–microbe interaction associated with salt tolerance in crops. We isolated the endophytic microbe from the root zone of halophytic grass. Later, the salt tolerance of the endophyte was tested in the saline medium and was identified using nucleotide sequencing (GenBank under the accession numbers: SUB9030920 AH1_AHK_ITS1 MW570850: SUB9030920 AH1_AHK_ITS4 MW570851). Rice and maize seeds were coated with identified endophyte Aspergillus terreus and were sown in separate plastic pots. Later 21-day-old seedlings were subjected to three NaCl concentrations, including 50, 100, and 150 mM salt stress. Under saline conditions, A. terreus showed a substantial increase in growth, biomass, relative water content, oxidative balance, and photochemical efficiency of rice and maize plants. The data reflected that the stimulation of gibberellic acid (GA) in treated leaves may be the main reason for the upregulation of photosynthesis and the antioxidant defense cascade. The data also depict the downregulation of oxidative damage markers malondialdehyde, hydrogen peroxide in rice and maize plants. Conclusively, salt-tolerant endophytic fungus A. terreus explicitly displayed the positive plant–microbe interaction by developing salt tolerance in rice and maize plants. Salt tolerance by endophytic fungus coincides with the enhanced GA concentration, which illustrated the stimulated physiological mechanism and gene in response to the extreme environmental crisis, resulting in improved crop productivity.

Highlights

Exposure to extreme climatic episodes is a serious problem for plant survival in arid or semiarid regions worldwide
Leaf relative water content (RWC) increased in maize and rice plants under salt stresses when plants were exposed to endophyte A. terreus
Salt-tolerant endophytic fungus A. terreus was applied in two different crops, i.e., maize and rice belonging to the same family

Summary

Introduction

Exposure to extreme climatic episodes is a serious problem for plant survival in arid or semiarid regions worldwide. Pitman and Lauchli (2002) reported that crop loss due to salinity is challenging to measure, but it is anticipated to Scrutinizes the Endophytes Effects increase by 2050. Abiotic stress, such as salinity and drought, exacerbates these conditions and has been shown to substantially decline agricultural production (Tavakkoli et al, 2011; Abideen et al, 2020). Salinity has affected nearly 1,128 million hectares of land (Wicke et al, 2011). It has previously been reported that crop plants at all stages of their life are sensitive to arid and saline areas, reducing growth (Nawaz et al, 2010). It is known that long-term saline irrigation causes adverse effects on plant physiology and the production of plant metabolites that affect the total biomass production (Hussain et al, 2019)

Methods

Results

Conclusion