Salt stress is a major abiotic factor that limits wheat production worldwide. However, this threat is increasing significantly because soil salinity affects approximately 20% of the irrigated agricultural land globally, leading to significant yield losses by impairing plant growth and photosynthetic efficiency. This study aimed to identify single-nucleotide polymorphisms (SNPs) associated with salt tolerance in wheat core collections during the heading stage under saline stress conditions. Chlorophyll content, a physiological indicator of salt tolerance at heading, and soil electrical conductivity (EC) were measured in 609 accessions and a Salt Tolerance Index (STI) was subsequently constructed. Genome-wide association studies (GWAS) were performed using a 35 K SNP chip to identify significant marker-trait associations. Three models (MLM, FarmCPU, and BLINK) were employed for the GWAS, with FarmCPU and BLINK demonstrating superior power over the MLM in controlling false positives. GWAS results revealed four significant SNPs (AX-94929101, AX- 94615611, AX-94510535, and AX-94411611) located on chromosomes 3D, 5D, and 7D. AX-94510535 exhibited significant phenotypic differences based on SNP genotype, suggesting its potential as a marker for STI. Furthermore, the identified candidate genes, TraesCS3D02G218100, TraesCS5D02G059500, and TraesCS5D02G175000, were implicated in biological processes such as DNA replication, cell death, and photosynthesis.
In Asia, where climate change is increasing the damage caused by cold stress, it is crucial to cultivate varieties with enhanced cold tolerance. In this study, the Tongil variety ‘Hanareum2’ was crossed with the Japonica variety ‘Unkwang’ to improve plant growth ability at low temperatures during the seedling stage. This led to the development of 234 recombinant inbred line (RIL) populations, and a linkage map was constructed using 249 single nucleotide polymorphism (SNP) markers. The RIL populations were transplanted to the field one month earlier than the standard transplanting period, and plant height (PH), leaf number (LN), and dry weight (DW) were measured to identify quantitative trait loci (QTL) associated with plant growth ability at low temperatures during the seedling stage. QTLs related to cold tolerance, particularly those carrying the ‘Unkwang’ allele, were identified in the PH and DW traits. For PH, the QTLs
This study was conducted to compare the agricultural characteristics of total 444 common bean accessions from Korea (296), China (76), and El Salvador (72). Days to flowering were ranged from 41 to 83 days with an average of 61 days. Days to sowing to maturing were ranged from 86 to 143 days with an average of 104 days. Common beans from El Salvador tend to bloom and mature 3 to 7 days earlier than Korea and China accessions. In growth habit, over 50% of Korea and China accessions were indeterminate and climbing type, but 90.1% from El Salvador were Semi-determinate and climbing type. Qualitative traits were much different among three countries. Eighty-two percentage of immature pod colors were dark pink from El Salvador, but many of those were pale yellow from Korea (77.6%) and China (61.8%). Seed shapes were divided into four types of round, oval, cubic and kidney type, and the highest percentage of those were 30.4% with kidney type. The highest of those was 36.6% with oval type from Korea, 55.3% with kidney type from China and 79.2% with cubic type from El Salvador. Morphological characteristics of common bean from El Salvador were much different from those of Korea and China, which is necessary to collect more germplasm from its native and expand genetic diversity of common beans. Four hundred thirty-five common beans from Korea, China and El Salvador were analyzed using SSR markers. Ninety-two alleles were detected with a lowest of 6 at the BM161, BM181 and a highest of 18 at the BM154, BM160. The average polymorphism information content (PIC) was 0.72. To similar with population size among three countries, 292 Korean accessions divided four replications with 73 accessions. As a result genetic diversity was the highest of 0.73 in Chinese populations, while the lowest of 0.48 in El Salvador populations.