Molecular Insights into Salinity Responsiveness in Contrasting Genotypes of Rice at the Seedling Stage.

Jingjing Zhang,Yiran Liu,Qiuxin Zhang,Weiyan Li,Yuexiong Zhang,Zemin Zhang,Hongkai Zhou,Tong Chen,Tingting Xu

doi:10.3390/ijms23031624

Abstract

Salinity is one of the most common unfavorable environmental conditions that limits plant growth and development, ultimately reducing crop productivity. To investigate the underlying molecular mechanism involved in the salinity response in rice, we initially screened 238 rice cultivars after salt treatment at the seedling stage and identified two highly salt-tolerant cultivars determined by the relative damage rate parameter. The majority of cultivars (94.1%) were ranked as salt-sensitive and highly salt-sensitive. Transcriptome profiling was completed in highly salt-tolerant, moderately salt-tolerant, and salt-sensitive under water and salinity treatments at the seedling stage. Principal component analysis displayed a clear distinction among the three cultivars under control and salinity stress conditions. Several starch and sucrose metabolism-related genes were induced after salt treatment in all genotypes at the seedling stage. The results from the present study enable the identification of the ascorbate glutathione pathway, potentially participating in the process of plant response to salinity in the early growth stage. Our findings also highlight the significance of high-affinity K+ uptake transporters (HAKs) and high-affinity K+ transporters (HKTs) during salt stress responses in rice seedlings. Collectively, the cultivar-specific stress-responsive genes and pathways identified in the present study act as a useful resource for researchers interested in plant responses to salinity at the seedling stage.

Highlights

State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangxi Key Laboratory of Rice Genetics and Breeding, Rice Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China
A total of 238 rice cultivar seedling genotypes were evaluated for their response to salt stress at the seedling stage
Seeds from different rice cultivars were germinated in distilled water and 150 mM NaCl solution, and the seedling percentage (SP) in water and salt solutions was recorded at 7 days after germination (DAG)

Summary

Introduction

State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Provincial Key Laboratory of Plant Molecular Breeding, South China Agricultural University, Guangxi Key Laboratory of Rice Genetics and Breeding, Rice Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China. To investigate the underlying molecular mechanism involved in the salinity response in rice, we initially screened 238 rice cultivars after salt treatment at the seedling stage and identified two highly salt-tolerant cultivars determined by the relative damage rate parameter. The cultivar-specific stress-responsive genes and pathways identified in the present study act as a useful resource for researchers interested in plant responses to salinity at the seedling stage. Soil salinity significantly adversely affects plant metabolism through osmotic stress and ion toxicity, affecting plant growth and development, as well as reducing water uptake. Over the past decades, emerging evidence has revealed the physiological, biochemical, and molecular mechanisms of salt tolerance in different plant species, including Arabidopsis and rice [2,3,4]. Osmotic stress causes a multitude of physiological changes, including cell membrane distortion, protein aggregation, DNA damage, disordered reactive oxygen species (ROS)

Methods

Results

Conclusion