Salt Tolerance Improvement in Rice through Efficient SNP Marker-Assisted Selection Coupled with Speed-Breeding

International Journal of Molecular Sciences

Takayuki Ohnishi¹  Toshie Sugiyama²  Takeshi Takamatsu²  MdMasud Rana²  Toshiaki Mitsui²  Kentaro Kaneko²  Kimiko Itoh²  Naoki Harada²  Marouane Baslam³  Hiroki Takagi⁴  Tetsu Kinoshita⁵ 

[1] Center for Education and Research of Community Collaboration, Utsunomiya University, Utsunomiya 321-8505, Japan;Department of Life and Food Sciences, Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan;Faculty of Agriculture, Niigata University, Niigata 950-2181, Japan;Faculty of Bioresources and Environmental Sciences, Ishikawa Prefectural University, Ishikawa 921-8836, Japan;Kihara Institute for Biological Research, Yokohama City University, Yokohama 244-0813, Japan;

关键词: hst1;    Na⁺ accumulation;    SNP;    rapid generation advance;    salt tolerant;    variant annotation;    whole-genome sequencing;   

DOI  :  10.3390/ijms20102585

来源: DOAJ

【 摘 要 】

Salinity critically limits rice metabolism, growth, and productivity worldwide. Improvement of the salt resistance of locally grown high-yielding cultivars is a slow process. The objective of this study was to develop a new salt-tolerant rice germplasm using speed-breeding. Here, we precisely introgressed the hst1 gene, transferring salinity tolerance from “Kaijin” into high-yielding “Yukinko-mai” (WT) rice through single nucleotide polymorphism (SNP) marker-assisted selection. Using a biotron speed-breeding technique, we developed a BC₃F₃ population, named “YNU31-2-4”, in six generations and 17 months. High-resolution genotyping by whole-genome sequencing revealed that the BC₃F₂ genome had 93.5% similarity to the WT and fixed only 2.7% of donor parent alleles. Functional annotation of BC₃F₂ variants along with field assessment data indicated that “YNU31-2-4” plants carrying the hst1 gene had similar agronomic traits to the WT under normal growth condition. “YNU31-2-4” seedlings subjected to salt stress (125 mM NaCl) had a significantly higher survival rate and increased shoot and root biomasses than the WT. At the tissue level, quantitative and electron probe microanalyzer studies indicated that “YNU31-2-4” seedlings avoided Na⁺ accumulation in shoots under salt stress. The “YNU31-2-4” plants showed an improved phenotype with significantly higher net CO₂ assimilation and lower yield decline than WT under salt stress at the reproductive stage. “YNU31-2-4” is a potential candidate for a new rice cultivar that is highly tolerant to salt stress at the seedling and reproductive stages, and which might maintain yields under a changing global climate.

【 授权许可】

Unknown