Publications by authors named "Istvan Rajcan"

New selection methods, using trait-specific markers (marker-assisted selection (MAS)) and/or genome-wide markers (genomic selection (GS)), are becoming increasingly widespread in breeding programs. This new era requires innovative and cost-efficient solutions for genotyping. Reduction in sequencing cost has enhanced the use of high-throughput low-cost genotyping methods such as genotyping-by-sequencing (GBS) for genome-wide single-nucleotide polymorphism (SNP) profiling in large breeding populations.

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Developing genetically resistant soybean cultivars is key in controlling the destructive Sclerotinia Stem Rot (SSR) disease. Here, a GWAS study in Canadian soybeans identified potential marker-trait associations and candidate genes, paving the way for more efficient breeding methods for SSR. Sclerotinia stem rot (SSR), caused by the fungal pathogen Sclerotinia sclerotiorum, is one of the most important diseases leading to significant soybean yield losses in Canada and worldwide.

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Spreng is a promising emerging oilseed crop, with its seed oil accounting for approximately 50% of the seed weight. oil contains a significant amount of vernolic acid, comprising two-thirds of its composition, which boasts various industrial applications, including acting as a stabilizer-plasticizer and natural dye. However, this species was known to have a high degree of seed-shattering and a low germination rate, which act as two important barriers to large-scale production and exploitation.

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Background: The potential of plant-based sources of vernolic acid to provide agricultural producers with a market diversification opportunity and industrial manufacturers with a renewable, environmentally friendly chemical feedstock is immense. The herbaceous wild spurge or caper spurge (Euphorbia lagascae Spreng) is the most promising source of vernolic acid, containing an average oil content of 50%, of which around 60% is vernolic acid. Its seed yield ranges between 500 and 2000 kg ha, and a theoretical yield of 180 kg ha of pure vernolic acid is possible.

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In Canada, the length of the frost-free season necessitates planting crops as early as possible to ensure that the plants have enough time to reach full maturity before they are harvested. Early planting carries inherent risks of cold water imbibition (specifically less than 4°C) affecting seed germination. A marker dataset developed for a previously identified Canadian soybean GWAS panel was leveraged to investigate the effect of cold water imbibition on germination.

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Article Synopsis
  • Mendelian heredity has been fundamental to plant breeding since the 19th century, but there are cases where it doesn't apply, known as non-Mendelian heredity.
  • Non-Mendelian heredity includes mechanisms like cytoplasmic inheritance, methylation, epigenetics, hybrid vigor, and loss of heterozygosity (LOH), which can influence plant breeding beyond just genetic factors.
  • Understanding non-Mendelian heredity is crucial for improving crop varieties, as this review discusses various forms, their inheritance patterns, applications in breeding, and their potential for future research.
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Article Synopsis
  • Soybean is a crucial crop due to its high protein and oil content, but there’s a challenge in breeding because seed protein and oil percentages negatively correlate; thus, detecting quantitative trait loci (QTL) is essential for improving these traits.
  • The research compares the effectiveness of machine learning (specifically support vector regression, SVR) to traditional GWAS methods (like FarmCPU) in identifying QTL relevant to soybean seed quality traits using data from 227 soybean genotypes.
  • Results indicated that SVR outperformed FarmCPU in finding QTL, highlighting the potential of advanced computational methods to enhance the accuracy and efficiency of genetic studies in crop breeding.
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Cinnamate 4-hydroxylase (C4H) is the first key cytochrome P450 monooxygenase (P450) enzyme in the phenylpropanoid pathway. It belongs to the CYP73 family of P450 superfamily, and catalyzes the conversion of trans-cinnamic acid to p-coumaric acid. Since p-coumaric acid serves as the precursor for the synthesis of a wide variety of metabolites involved in plant development and stress resistance, alteration in the expression of soybean C4H genes is expected to affect the downstream metabolite levels, and its ability to respond to stress.

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rAMP-seq based genomic selection for agronomic traits has been shown to be a useful tool for winter wheat breeding programs by increasing the rate of genetic gain. Genomic selection (GS) is an effective strategy to employ in a breeding program that focuses on optimizing quantitative traits, which results in the ability for breeders to select the best genotypes. GS was incorporated into a breeding program to determine the potential for implementation on an annual basis, with emphasis on selecting optimal parents and decreasing the time and costs associated with phenotyping large numbers of genotypes.

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Fast-paced yield improvement in strategic crops such as soybean is pivotal for achieving sustainable global food security. Precise genomic selection (GS), as one of the most effective genomic tools for recognizing superior genotypes, can accelerate the efficiency of breeding programs through shortening the breeding cycle, resulting in significant increases in annual yield improvement. In this study, we investigated the possible use of haplotype-based GS to increase the prediction accuracy of soybean yield and its component traits through augmenting the models by using sophisticated machine learning algorithms and optimized genetic information.

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Multi-Parent Advanced Generation Inter-Cross (MAGIC) populations are emerging genetic platforms for high-resolution and fine mapping of quantitative traits, such as agronomic and seed composition traits in soybean ( L.). We have established an eight-parent MAGIC population, comprising 721 recombinant inbred lines (RILs), through conical inter-mating of eight soybean lines.

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Article Synopsis
  • * The study analyzed 14 seed quality traits in Canada and 2 in Ukraine, using a panel of 184 soybean genotypes grown in different locations during 2018 and 2019.
  • * Findings showed distinct accumulation patterns for protein and oil in the two regions, with no shared QTL for these traits; instead, nine Canadian-specific QTL for protein were identified, indicating the need for tailored breeding strategies for each mega-environment.
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A genome-wide association study (GWAS) is currently one of the most recommended approaches for discovering marker-trait associations (MTAs) for complex traits in plant species. Insufficient statistical power is a limiting factor, especially in narrow genetic basis species, that conventional GWAS methods are suffering from. Using sophisticated mathematical methods such as machine learning (ML) algorithms may address this issue and advance the implication of this valuable genetic method in applied plant-breeding programs.

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The SoyaGen project was a collaborative endeavor involving Canadian soybean researchers and breeders from academia and the private sector as well as international collaborators. Its aims were to develop genomics-derived solutions to real-world challenges faced by breeders. Based on the needs expressed by the stakeholders, the research efforts were focused on maximizing realized yield through optimization of maturity and improved disease resistance.

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Cytochrome P450 monooxygenases (P450) participate in the catalytic conversion of biological compounds in a plethora of metabolic pathways, such as the biosynthesis of alkaloids, terpenoids, phenylpropanoids, and hormones in plants. Plants utilize these metabolites for growth and defense against biotic and abiotic stress. In this study, we identified 346 P450 (GmP450) enzymes encoded by 317 genes in soybean where 26 genes produced splice variants.

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Genome-wide association study (GWAS) has emerged in the past decade as a viable tool for identifying beneficial alleles from a genomic diversity panel. In an ongoing effort to improve soybean [ (L.) Merr.

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Significant QTL for sucrose concentration have been identified using a historical soybean genomic panel, which could aid in the development of food-grade soybean cultivars. Soybean (Glycine max (L.) Merr) is a crop of global importance for both human and animal consumption, which was domesticated in China more than 6000 years ago.

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In conjunction with big data analysis methods, plant omics technologies have provided scientists with cost-effective and promising tools for discovering genetic architectures of complex agronomic traits using large breeding populations. In recent years, there has been significant progress in plant phenomics and genomics approaches for generating reliable large datasets. However, selecting an appropriate data integration and analysis method to improve the efficiency of phenome-phenome and phenome-genome association studies is still a bottleneck.

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The accurate determination of soybean pubescence is essential for plant breeding programs and cultivar registration. Currently, soybean pubescence is classified visually, which is a labor-intensive and time-consuming activity. Additionally, the three classes of phenotypes (tawny, light tawny, and gray) may be difficult to visually distinguish, especially the light tawny class where misclassification with tawny frequently occurs.

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Type I Diacylglycerol acyltransferase (DGAT1) catalyzes the final step of the biosynthesis process of triacylglycerol (TAG), the major storage lipids in plant seeds, through the esterification of diacylglycerol (DAG). To characterize the function of DGAT1 genes on the accumulation of oil and other seed composition traits in soybean, transgenic lines were generated via trans-acting siRNA technology, in which three DGAT1 genes (Glyma.13G106100, Glyma.

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Article Synopsis
  • A global haplotype map for soybean (GmHapMap) was created using whole-genome data from 1007 Glycine max accessions, resulting in 14.9 million variants and 4.3 million tag SNPs.
  • The study found that sampling 800 accessions provided extensive coverage of soybean genetic diversity, with a successful imputation of variants in previously genotyped accessions.
  • A local association analysis led to the identification of a candidate SNP linked to seed oil content and highlighted the potential of gene-centric haplotypes for understanding phenotypic variation and exploring gene functions.
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