Song Jiawei, Yang Hui, Qiao Chengbin, Zhu Chunyan, Bai Tianliang, Du Huaidong, Ma Shuaiguo, Wang Na, Luo Chengke, Zhang Yinxia, Ma Tianli, Li Peifu, Tian Lei
School of Agriculture, Ningxia University, Yinchuan, China.
Key Laboratory of Modern Molecular Breeding for Dominant and Special Crops in Ningxia, Ningxia University, Yinchuan, China.
Front Plant Sci. 2023 Mar 17;14:1095929. doi: 10.3389/fpls.2023.1095929. eCollection 2023.
Soil salinity seriously restricts rice growth, development, and production globally. Chlorophyll fluorescence and ion content reflect the level of injury and resistance of rice under salt stress. To understand the differences in the response mechanisms of rice with varying degrees of salt tolerance, we analyzed the chlorophyll fluorescence characteristics and ion homeostasis of 12 rice germplasm accessions by comprehensive evaluation of phenotype, haplotype, and expression of salt tolerance-related genes. The results revealed that salt-sensitive accessions were rapidly affected by the damage due to salinity. Salt tolerance score (STS) and relative chlorophyll relative content (RSPAD) were extremely significantly reduced (p<0.01), and chlorophyll fluorescence and ion homeostasis were influenced by various degrees under salt stress. The STS, RSPAD, and five chlorophyll fluorescence parameters of salt-tolerant accessions (STA) were significantly higher than that of salt-sensitive accessions (SSA). Principal component analysis (PCA) with 13 indices suggested three principal components (PCs), with a cumulative contribution rate of 90.254%, which were used to screen Huangluo (typical salt-tolerant germplasm) and Shanfuliya (typical salt-sensitive germplasm) based on the comprehensive evaluation -value ( ). The expression characteristics of chlorophyll fluorescence genes ( and ) and ion transporter protein genes (, , , , , and ) were analyzed. The expressions of these genes were higher in Huangluo than in Shanfuliya under salt stress. Haplotype analysis revealed four key variations associated with salt tolerance, including an SNP (+1605 bp) within exon, an SSR (-1231 bp) within promoter, an indel site at promoter (-822 bp), and an SNP (-1866 bp) within promoter. Variation in OsABCI7 protein structure and differential expression of these three ion-transporter genes may contribute to the differential response of rice to salt stress.
土壤盐碱化严重限制了全球水稻的生长、发育和产量。叶绿素荧光和离子含量反映了盐胁迫下水稻的损伤程度和抗性水平。为了解不同耐盐程度水稻响应机制的差异，我们通过对表型、单倍型和耐盐相关基因表达的综合评估，分析了12份水稻种质资源的叶绿素荧光特性和离子稳态。结果表明，盐敏感种质迅速受到盐害影响。耐盐评分（STS）和相对叶绿素相对含量（RSPAD）极显著降低（p<0.01），盐胁迫下叶绿素荧光和离子稳态受到不同程度的影响。耐盐种质（STA）的STS、RSPAD和5个叶绿素荧光参数显著高于盐敏感种质（SSA）。基于13个指标的主成分分析（PCA）表明有三个主成分（PCs），累积贡献率为90.254%，用于基于综合评价值（ ）筛选黄洛（典型耐盐种质）和汕辐鲤（典型盐敏感种质）。分析了叶绿素荧光基因（ 和 ）和离子转运蛋白基因（ 、 、 、 、 和 ）的表达特征。盐胁迫下，这些基因在黄洛中的表达高于汕辐鲤。单倍型分析揭示了4个与耐盐性相关的关键变异，包括 外显子内的一个SNP（+1605 bp）、 启动子内的一个SSR（-1231 bp）、 启动子处的一个插入缺失位点（-822 bp）和 启动子内的一个SNP（-1866 bp）。OsABCI7蛋白结构变异和这三个离子转运基因的差异表达可能导致水稻对盐胁迫的不同响应。
