Plant Genome最新文献

SoySNP50K and SoySNP6K are commonly used for soybean (Glycine max) genotyping. The SoySNP50K assay has been used to genetically analyze the entire USDA Soybean Germplasm Collection, while the SoySNP6K assay, containing a subset of 6000 single-nucleotide polymorphisms (SNPs) from SoySNP50K, has been used for quantitative trait loci mapping of different traits. To meet the needs for genomic selection, selection of parents for crosses, and characterization of breeding populations, especially early selection of ideal offspring from thousands of lines, we developed two assays, SoySNP3K and SoySNP1K, containing 3072 and 1252 SNPs, respectively, based on SoySNP50K and SoySNP6K mark sets. These two assays also contained the trait markers reported or contributed by soybean breeders. The SNPs in the SoySNP3K are a subset from SoySNP6K, while the SNPs in the SoySNP1K are a subset from SoySNP3K. These SNPs were chosen to reduce the SNP number in the large linkage blocks while capturing as much of the haplotype diversity as possible. They are highly polymorphic and of high quality. The mean minor allele frequencies of the SNPs in the southern and northern US elites were 0.25 and 0.27 for SoySNP3K, respectively, and 0.29 and 0.33 for SoySNP1K. The selected SNPs are a valuable source for developing targeted amplicon sequencing assay or beadchip assay in soybean. SoySNP3K and SoySNP1K assays are commercialized by Illumina Inc. and AgriPlex Genomics, respectively. Together with SoySNP50K and SoySNP6K, a series of nested assays with different marker densities will serve as additional low-cost genomic tools for genetic, genomic, and breeding research.

In plantae, basic leucine zipper (bZIP) transcription factors (TFs) are widespread and regulate a variety of biological processes under abiotic stress. However, it has not been extensively studied in Rosaceae, and the functional effects of bZIP on Eriobotrya japonica under salt stress are still unknown. Therefore, in this study, the bZIP TF family of 12 species of Rosaceae was analyzed by bioinformatics method, and the expression profile and quantitative real-time polymerase chain reaction of E. japonica under salt stress were analyzed. The results showed that a total of 869 bZIP TFs were identified in 12 species of Rosaceae and divided into nine subfamilies. Differences in promoter cis-elements between subfamilies vary depending on their role. Species belonging to the same subfamily have a similar number of chromosomes and the number of genes contained on each chromosome. Gene duplication analysis has found segmental duplication to be a prime force in the evolution of Rosaceae species. In addition, nine EjbZIPs were significantly different, including seven up-regulated and two down-regulated in E. japonica under salt stress. Especially, EjbZIP13 was involved in the expression of SA-responsive proteins by binding to the NPR1 gene. EjbZIP27, EjbZIP30, and EjbZIP38 were highly expressed in E. japonica under salt stress, thus improving the salt tolerance capacity of the plants. These results can provide a theoretical basis for exploring the characteristics and functions of the bZIP TF family in more species and breeding salt-tolerant E. japonica varieties. It also provides a reference for resolving the response mechanism of bZIP TF in 12 Rosaceae species under salt stress.

Seven in absentia proteins, which contain a conserved SINA domain, are involved in regulating various aspects of wheat (Triticum aestivum L.) growth and development, especially in response to environmental stresses. However, it is unclear whether TaSINA family members are involved in regulating grain development until now. In this study, the expression pattern, genomic polymorphism, and relationship with grain-related traits were analyzed for all TaSINA members. Most of the TaSINA genes identified showed higher expression levels in young wheat spikes or grains than other organs. The genomic polymorphism analysis revealed that at least 62 TaSINA genes had different haplotypes, where the haplotypes of five genes were significantly correlated with grain-related traits. Kompetitive allele-specific PCR markers were developed to confirm the single nucleotide polymorphisms in TaSINA101 and TaSINA109 among the five selected genes in a set of 292 wheat accessions. The TaSINA101-Hap II and TaSINA109-Hap II haplotypes had higher grain weight and width compared to TaSINA101-Hap I and TaSINA109-Hap I in at least three environments, respectively. The qRT-PCR assays revealed that TaSINA101 was highly expressed in the palea shell, seed coat, and embryo in young wheat grains. The TaSINA101 protein was unevenly distributed in the nucleus when transiently expressed in the protoplast of wheat. Three homozygous TaSINA101 transgenic lines in rice (Oryza sativa L.) showed higher grain weight and size compared to the wild type. These findings provide valuable insight into the biological function and elite haplotype of TaSINA family genes in wheat grain development at a genomic-wide level.

Water absorption capacity (WAC) influences various aspects of bread making, such as loaf volume, bread yield, and shelf life. Despite its importance in the baking process and end-product quality, its genetic determinants are less explored. To address this limitation, a genome-wide association study was conducted on 337 hard wheat (Triticum aestivum L.) genotypes evaluated over 5 years in multi-environmental trials. Phenotyping was done using the solvent retention capacity (SRC) test with water (SRC-water), sucrose (SRC-sucrose), lactic acid (SRC-lactic acid), and sodium carbonate (SRC-carbonate) as solvents. Individuals were genotyped using genotyping-by-sequencing to detect single nucleotide polymorphisms across the wheat genome. To detect the genomic regions that underline the SRCs and gluten performance index (GPI), a genome-wide association study was performed using six multi-locus models using the mrMLM package in R. Adjusted means for SRC-water ranged from 54.1% to 66.5%, while SRC-carbonate exhibited a narrow range from 84.9% to 93.9%. Moderate to high genomic heritability values were observed for SRCs and GPI, ranging from h² = 0.61 to 0.88. The genome-wide association study identified a total of 42 quantitative trait nucleotides (QTNs), of which five explained over 10% of the phenotypic variation (R² ≥ 10%). Most of the QTNs were detected on chromosomes 1A, 1B, 3B, and 5B. Few QTNs, such as S1A_5190318, S1B_3282665, S4D_472908721, and S7A_37433960, were located near gliadin, glutenin starch synthesis, and galactosyltransferase genes. Overall, these results show WAC to be under polygenic genetic control, with genes involved in the synthesis of key flour components influencing overall water absorption.

We aimed to identify HD-Zip (homologous domain leucine zipper) family genes based on the complete Sophora alopecuroides genome sequence. Eighty-six Sophora alopecuroides HD-Zip family (SaHDZ) genes were identified and categorized into four subclasses using phylogenetic analysis. Chromosome localization analysis revealed that these genes were distributed across 18 chromosomes. Gene structure and conserved motif analysis showed high similarity among members of the SaHDZ genes. Prediction analysis revealed 71 cis-acting elements in SaHDZ genes. Transcriptome and quantitative real-time polymerase chain reaction analyses showed that under salt stress, SaHDZ responded positively in S. alopecuroides, and that SaHDZ22 was significantly upregulated afterward. Functional verification experiments revealed that SaHDZ22 overexpression increased the tolerance of Arabidopsis to salt and osmotic stress. Combined with cis-acting element prediction and expression level analysis, HD-Zip family transcription factors may be involved in regulating the balance between plant growth and stress resistance under salt stress by modulating the expression of auxin and abscisic acid signaling pathway genes. The Sophora alopecuroides adenylate kinase protein (SaAKI) and S. alopecuroides tetrapeptide-like repeat protein (SaTPR; pCAMBIA1300-SaTPR-cLUC) expression levels were consistent with those of SaHDZ22, indicating that SaHDZ22 may coordinate with SaAKI and SaTPR to regulate plant salt tolerance. These results lay a foundation in understanding the salt stress response mechanisms of S. alopecuroides and provide a reference for future studies oriented toward exploring plant stress resistance.

Genomic prediction is a modern approach that uses genome-wide markers to predict the genetic merit of unphenotyped individuals. With the potential to reduce the breeding cycles and increase the selection accuracy, this tool has been designed to rank genotypes and maximize genetic gains. Despite this importance, its practical implementation in breeding programs requires critical allocation of resources for its application in a predictive framework. In this study, we integrated genetic and data-driven methods to allocate resources for phenotyping and genotyping tailored to genomic prediction. To this end, we used a historical blueberry (Vaccinium corymbosun L.) breeding dataset containing more than 3000 individuals, genotyped using probe-based target sequencing and phenotyped for three fruit quality traits over several years. Our contribution in this study is threefold: (i) for the genotyping resource allocation, the use of genetic data-driven methods to select an optimal set of markers slightly improved prediction results for all the traits; (ii) for the long-term implication, we carried out a simulation study and emphasized that data-driven method results in a slight improvement in genetic gain over 30 cycles than random marker sampling; and (iii) for the phenotyping resource allocation, we compared different optimization algorithms to select training population, showing that it can be leveraged to increase predictive performances. Altogether, we provided a data-oriented decision-making approach for breeders by demonstrating that critical breeding decisions associated with resource allocation for genomic prediction can be tackled through a combination of statistics and genetic methods.

In this study, the contents of four carotenoids in 244 maize inbred lines were detected and about three million single nucleotide polymorphisms (SNPs) for genome-wide association study to preliminarily analyze the genetic mechanism of maize kernel carotenoids. We identified 826 quantitative trait loci (QTLs) were significantly associated with carotenoids contents, and two key candidate genes Zm00001d029526 (CYP18) and Zm00001d023336 (wrky91) were obtained. In addition, we found a germplasm IL78 with higher carotenoids. The results of this study can provide a theoretical basis for screening genes that guide kernel carotenoids selection breeding.

Salt stress is one of the primary environmental stresses limiting plant growth and production and adversely affecting the growth, development, yield, and fruit quality of Citrus sinensis. bHLH (basic helix-loop-helix) genes are involved in many bioregulatory processes in plants, including growth and development, phytohormone signaling, defense responses, and biosynthesis of specific metabolites. In this study, by bioinformatics methods, 120 CsbHLHgenes were identified, and phylogenetic analysis classified them into 18 subfamilies that were unevenly distributed on nine chromosomes. The cis-acting elements of the CsbHLH genes were mainly hormone-related cis-acting elements. Seventeen CsbHLH genes exhibited significant differences in expression under salt stress. Six CsbHLH genes with significant differences in expression were randomly selected for quantitative real-time polymerase chain reaction (qRT-PCR) validation. The qRT-PCR results showed a strong correlation with the transcriptome data. Phytohormones such as jasmonic acid (JA) are essential for biotic and abiotic stress responses in plants, and CsbHLH55 and CsbHLH87 are considered candidate target genes for sweet orange MYC2 transcription factors involved in the JA signaling pathway. These genes are the main downstream effectors in the JA signaling pathway and can be activated to participate in the JA signaling pathway. Activation of the JA signaling pathway inhibits the production of reactive oxygen species and improves the salt tolerance of sweet orange plants. The CsbHLH55 and CsbHLH87 genes could be candidate genes for breeding new transgenic salt-resistant varieties of sweet orange.

Mid-density targeted genotyping-by-sequencing (GBS) combines trait-specific markers with thousands of genomic markers at an attractive price for linkage mapping and genomic selection. A 2.5K targeted GBS assay for potato (Solanum tuberosum L.) was developed using the DArTag technology and later expanded to 4K targets. Genomic markers were selected from the potato Infinium single nucleotide polymorphism (SNP) array to maximize genome coverage and polymorphism rates. The DArTag and SNP array platforms produced equivalent dendrograms in a test set of 298 tetraploid samples, and 83% of the common markers showed good quantitative agreement, with RMSE (root mean squared error) <0.5. DArTag is suited for genomic selection candidates in the clonal evaluation trial, coupled with imputation to a higher density platform for the training population. Using the software polyBreedR, an R package for the manipulation and analysis of polyploid marker data, the RMSE for imputation by linkage analysis was 0.15 in a small half-diallel population (N = 85), which was significantly lower than the RMSE of 0.42 with the random forest method. Regarding high-value traits, the DArTag markers for resistance to potato virus Y, golden cyst nematode, and potato wart appeared to track their targets successfully, as did multi-allelic markers for maturity and tuber shape. In summary, the potato DArTag assay is a transformative and publicly available technology for potato breeding and genetics.