Istvan Rajcan

Istvan Rajcan
University of Guelph | UOGuelph · Department of Plant Agriculture

Ph.D.

About

156
Publications
29,515
Reads
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Citations
Introduction
Dr. Rajcan’s research focuses on the genetics of seed compositional traits (e.g., modified fatty acids, isoflavones, vitamin E) for food and industrial applications of soybean. Genetic variation for yield and disease resistance traits is explored using exotic and elite germplasm sources. He collaborates widely with Canadian and international scientists. Field work focuses on phenotyping and soybean cultivar development in conjunction with genomics approaches in the lab.
Additional affiliations
March 1998 - present
University of Guelph
Position
  • Professor (Full)
Description
  • Soybean Breeding & Genetics
Education
September 1992 - August 1996
University of Guelph
Field of study
  • Crop Breeding and Genetics
October 1984 - December 1988
University of Novi Sad
Field of study
  • Field and Vegetable Crops

Publications

Publications (156)
Article
Full-text available
Genotyping through the pedigrees of elite soybean [Glycine max (L.) Merr.] cultivars developed by a breeding program represents an opportunity to explore and characterize various molecular and genetic changes that are a direct result of long-term selection by soybean breeders. For soybeans bred for Ontario Canada, one such elite cultivar was OAC Ba...
Article
Full-text available
One of the goals of plant breeding is to increase yield with improved quality characters. Plant introductions (PI) are a rich source of favorable alleles that could improve different characters in modern soybean [Glycine max (L.) Merril] including yield. The objectives of this study were to identify yield QTL underlying the genetic basis for differ...
Article
Full-text available
Soybean seed is a major source of oil for human consumption worldwide and the main renewable feedstock for biodiesel production in North America. Increasing seed oil concentration in soybean [Glycine max (L.) Merrill] with no or minimal impact on protein concentration could be accelerated by exploiting quantitative trait loci (QTL) or gene-specific...
Article
As the demand for plant-based pet foods is increasing exponentially, pet-food companies have considerable financial investments in this area. While most plant source proteins contain all essential amino acids, few contain all essential amino acids in sufficient amounts to fulfill the nutritional requirements. Therefore, the optimum balance of prote...
Article
Despite mounting concerns regarding the narrowness of the genetic base of soybean [(Glycine max (L.) Merr.] in North America and the challenges that it may pose in the changing global environment and climate, exotic germplasm remains seldom used by breeders owing to various concerns. The objective of this study was to evaluate a Genome Wide Associa...
Article
Full-text available
Key Message Identifying QTL associated with soybean seed quality traits from a diverse GWAS panel cultivated in Canadian and Ukrainian mega-environments may facilitate future cultivar development for foreign markets. Abstract Understanding the complex genetic basis of seed quality traits for soybean in the mega-environments (MEs) is critical for d...
Article
Full-text available
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 (Glycine max L.). We have established an eight-parent MAGIC population, comprising 721 recombinant inbred lines (RILs), through conical...
Article
Full-text available
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 mathe...
Article
Full-text available
Key message 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. Abstract 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...
Article
Full-text available
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 identifie...
Article
Full-text available
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...
Article
Full-text available
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 [Glycine max (L.) Merr.], which is the third largest field crop in Canada, a GWAS was conducted to identify novel alleles underlying seed yield and seed quali...
Article
Improvement of soybean [Glycine max (L.) Merr.] seed quality traits in addition to agronomic traits requires a detailed understanding of correlations between these traits. The objective of this study was to determine the correlations between seed compositions in soybeans grown in Canadian and Ukrainian mega-environments (MEs). The correlations betw...
Article
Full-text available
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 re...
Preprint
Genome-wide association study (GWAS) is currently one of the most recommended approaches for discovering quantitative trait loci (QTL) associated with complex traits in plant species. Insufficient statistical power is a limiting factor that current conventional GWAS methods are suffering from, especially in narrow genetic bases plants such as soybe...
Article
Full-text available
Soybean [ Glycine max (L.) Merr.] is the world's leading legume crop and the largest oilseed crop. It forms a symbiotic relationship with rhizobia bacteria residing in root nodules that provide fixed nitrogen to host plants through symbiotic nitrogen fixation (SNF). In soybean, it has been widely reported that the highest SNF occurs at the pod-fill...
Article
Genetic improvement of soybean, one of the major crops providing edible oil and protein-rich food, is important to ensure balanced nutrition for the growing world population. To make soybean cultivation more rewarding, an increase in seed oil and protein content is most desirable. Here, a critical review of the efforts employed over a half-century...
Article
Full-text available
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, espe...
Article
Insoybean [Glycine max (L.) Merr.], seed oil concentration is a complex quantitative trait, and genomic selection (GS) has been shown to be a valuable tool for performing selection on such traits. The objectives of this study were to evaluate multiple GS models for seed oil concentration using a low‐density marker panel in four biparental soybean p...
Preprint
Genome-wide association study (GWAS) is currently one of the important approaches for discovering quantitative trait loci (QTL) associated with traits of interest. However, insufficient statistical power is the limiting factor in current conventional GWAS methods for characterizing quantitative traits, especially in narrow genetic bases plants such...
Article
Maximizing yield is very important when developing new cultivars. However, yield must usually be improved jointly with other key traits, which can prove challenging when they are unfavorably correlated. Genomic predictions can facilitate the selection of promising lines among the progeny of crosses, but it may also help in selecting crosses that ar...
Article
Lodging resistance is an important objective for soybean [Glycine max (L.) Merr.] breeding, but selection for this trait has been difficult since the resistance is controlled by multiple genes and these genes interact with the environment. One hundred thirty of 139 lines constituting a soybean GWAS panel were phenotyped for stem pushing resistance,...
Article
Full-text available
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 line...
Preprint
Full-text available
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. A concern about losing genetic diversity as a result of decades of breeding has been expressed by soybean researchers. In order to develop new cultivars, it is critical for breeders to unde...
Article
The DP‐305423‐1 transgene elevates oleic acid concentration and reduces polyunsaturated fatty acids in soybean [Glycine max (L.) Merr.] oil, resulting in increased oxidative stability. The objective of this research was to investigate the effect of the DP‐305423‐1 transgene on agronomic and seed traits using four backcross derived soybean populatio...
Article
Full-text available
Here we describe a worldwide haplotype map for soybean (GmHapMap) constructed using whole‐genome sequence data for 1,007 Glycine max accessions and yielding 14.9 million variants as well as 4.3M tag single nucleotide polymorphisms (SNPs). When sampling random subsets of these accessions, the number of variants and tag SNPs plateaued beyond approxim...
Article
Full-text available
Key message: Identification of marker-trait associations and trait-associated haplotypes in breeding germplasm identifies regions under selection and highlights changes in haplotype diversity over decades of soybean improvement in Canada. Understanding marker-trait associations using genome-wide association in soybean is typically carried out in d...
Article
Full-text available
Key message We explored the genetic basis of SNF-related traits through GWAS and identified 40 candidate genes. This study provides fundamental insights into SNF-related traits and will accelerate efforts for SNF breeding. Abstract Symbiotic nitrogen fixation (SNF) increases sustainability by supplying biological nitrogen for crops to enhance yiel...
Article
Full-text available
The plant phenotyping community is adopting technological innovations in order to record phenotypic attributes more quickly and objectively. Low altitude aerial imaging is an appealing option for increasing throughput but there are still challenges in the image processing pipeline. One such challenge involves the assignment of a spatial reference t...
Article
Full-text available
Key message Genetic diversity in Canadian soybean is maintained over decades of selection in two public breeding programs. Breeders have used a portion of the genetic diversity available in germplasm collections. Abstract Both public and private breeding efforts have been critical for the development of soybean cultivars grown around the world. Gl...
Article
The apparent efficacy of linuron to control pigweeds (Amaranthus spp.) has declined in Ontario, Canada, in past decades, possibly due to resistance. Samples were collected in multiple fields across Ontario with reported linuron failure. These were characterized at the whole-plant and molecular levels. Screening with linuron revealed resistance in s...
Article
Full-text available
Common beans (Phaseolus vulgaris) form a relationship with nitrogen-fixing rhizobia and through a process termed symbiotic nitrogen fixation (SNF) which provides them with a source of nitrogen. However, beans are considered poor nitrogen fixers, and modern production practices involve routine use of N fertilizer, which leads to the down-regulation...
Preprint
Full-text available
Here we describe the first worldwide haplotype map for soybean (GmHapMap) constructed using whole-genome sequence data for 1,007 Glycine max accessions and yielding 15 million variants. The number of unique haplotypes plateaued within this collection (4.3 million tag SNPs) suggesting extensive coverage of diversity within the cultivated germplasm....
Article
Full-text available
Key message Significant QTL for soyasaponin I, as the major component of the soyasaponin B, have been identified using an RIL soybean population, which could facilitate the development of functional food soybean cultivars. Abstract Soyasaponin B forms that are naturally found in soybean (Glycine max [L.] Merr.) seed, have been of interest to the f...
Article
Domestication is an important key co‐evolutionary process through which humans have extensively altered the genomic make‐up and appearance of both plants and animals. The identification of domestication‐related genes remains very arduous. In this study, we present a systematic analytical approach that harnesses two recent advances in genomics, whol...
Article
Isoflavones are plant secondary metabolites produced in soybean (Glycine max), which provide plant defense against pathogens and are beneficial to human health. Soybean cyst nematode (SCN) is a major yield‐limiting pest in most soybean‐producing area across the world. Traits, seed isoflavones and SCN resistance are quantitative in nature, and their...
Article
Full-text available
Genetic hitchhiking methods used to uncover selection signatures related to traits of agronomic importance in crops have primarily been used at the level of domestication by comparing groups of wild germplasm to landraces or elite breeding lines. In this study, two groups of cultivars defined by an elite Canadian soybean cultivar, ‘OAC Bayfield’, w...
Article
Full-text available
The apple ( × Borkh.) is an economically and culturally important crop grown worldwide. Growers of this long-lived perennial must produce fruit of adequate quality while also combatting abiotic and biotic stress. Traditional apple breeding can take up to 20 yr from initial cross to commercial release, but genomics-assisted breeding can help acceler...
Article
Oil value is determined by the functional qualities imparted from the fatty acid profile. Soybean oil historically had excellent use in foods and industry; the need to increase the stability of the oil without negative health consequences has led to a decline in soybean oil use. One solution to make the oil stable is to have high oleic acid (>70%)...
Article
Soybean (Glycine max [L.] Merr.) is a major isoflavone producing legume. Isoflavones and their derivatives function as phytoalexins that may function in protecting plants against pathogens. They are also known as phytoestrogens in the human diet, which have putative positive human health effects such as reduced risk of breast and prostate cancers,...
Article
Full-text available
Glyphosate-resistant populations of Conyza canadensis have been spreading at a rapid rate in Ontario, Canada, since first being documented in 2010. Determining the genetic relationship among existing Ontario populations is necessary to understand the spread and selection of the resistant biotypes. The objectives of this study were to: (1) character...
Article
Full-text available
Next-generation sequencing (NGS) and bioinformatics tools have greatly facilitated the characterization of nucleotide variation; nonetheless, an exhaustive description of both SNP haplotype diversity and of structural variation remains elusive in most species. In this study, we sequenced a representative set of 102 short-season soybeans and achieve...
Article
Full-text available
Breeding apples is a long-term endeavour and it is imperative that new cultivars are selected to have outstanding consumer appeal. This study has taken the approach of merging sensory science with genome wide association analyses in order to map the human perception of apple flavour and texture onto the apple genome. The goal was to identify genomi...
Data
Phenotypic distributions of 78 apple cultivars evaluated for instrumental and sensory fruit quality in 2012 and 2013. (PDF)
Data
Spearman rank correlations between all fruit quality traits. The trait “Designation” refers to apple cultivars as either heritage or commercial. Rank correlations were estimated by comparison of fruit quality trait values in 78 apple genotypes for two-year combined data. (PDF)
Data
Linkage disequilibrium decay summary and SNP distribution by chromosome for 85 apple cultivars. (PDF)
Data
Genotypes of apple cultivars at the MdACO1 and MdPG1 gene loci. Alleles are indicated as: “F” = homozygous favourable, “H” = heterozygous, “N” = homozygous non-favourable and “-” = unknown. Genotyping was based on MdACO1 and MdPG1 apple texture candidate gene studies [13,15]. (PDF)
Data
Polymorphism data of all SNPs in all apple accessions including chromosome location and physical location. (7Z)
Data
Variance statistics for allele class of SNPs associated with fruit quality traits. (PDF)
Conference Paper
Full-text available
Sclerotinia stem rot or white mold (WM) is an important fungal disease affecting soybean production [Glycine max (L.) Merr.]. White mold is prevalent in cool and moist environments and causes significant damage to yield and grain quality particularly in the soybean growing regions of northern United States and Canada. Although sources of complete r...
Article
Full-text available
Identity recognition systems allow plants to tailor competitive phenotypes in response to the genetic relatedness of neighbours. There is limited evidence for the existence of recognition systems in crop species and whether they operate at a level that would allow for identification of different degrees of relatedness. Here, we test the responses o...
Chapter
The oilseed crops canola, soybean, linseed, and sunflower are grown in the three North American countries to varying extent. Among these, canola and soybean represent 95% of the total oilseed acreage in North America. Canada is the largest producer of canola, while the United States is the largest producer of soybean. Most of the North American lin...
Article
The oilseed crops canola, soybean, linseed, and sunflower are grown in the three North American countries to varying extent. Among these, canola and soybean represent 95% of the total oilseed acreage in North America. Canada is the largest producer of canola, while the United States is the largest producer of soybean. Most of the North American lin...
Article
Soybean (Glycine max [L.] Merr.) is cultivated primarily for its protein and oil in the seed. In addition, soybean seeds contain nutraceutical compounds such as tocopherols (vitamin E), which are powerful antioxidants with health benefits. The objective of this study was to identify molecular markers linked to quantitative trait loci (QTL) that aff...
Article
OAC Prosper is a semi-determinate food-grade soybean (Glycine max (L.) Merr.) cultivar with high yield potential, high seed protein concentration, and resistance to soybean cyst nematode. OAC Prosper is developed and recommended for soybean growing areas in southwestern Ontario with 2950 or greater crop heat units. OAC Prosper has a relative maturi...
Article
Full-text available
The apple (Malus×domestica Borkh.) is one of the world’s most widely grown and valuable fruit crops. With demand for apples year round, storability has emerged as an important consideration for apple breeding programs. Soft scald is a cold storage-related disorder that results in sunken, darkened tissue on the fruit surface. Apple breeders are keen...
Article
Candor is a yellow hilum tofu-type soybean (Glycine max (L.) Merr.) cultivar with extra-large seed size, high protein level, and high yield potential. Candor is adapted to and recommended for soybean growing regions in southwestern Ontario with 3000 or greater crop heat units. Candor has a relative maturity of 2.1.
Article
OAC Brooke is an indeterminate food-grade soybean (Glycine max [L.] Merr.) cultivar with high yield potential and high seed protein concentration. OAC Brooke is adapted to and recommended for soybean growing regions in southwestern Ontario with 3050 or greater crop heat units. OAC Brooke has a relative maturity of 2.2.
Article
Full-text available
Soybean seeds [Glycine max (L.) Merrill] are a major source of tocopherols that provide many human health benefits including decrease in lung cancer risk and osteoporosis. The objectivesof this study were: (i) to determine the impact of genotype, environment, and genotype x environment on soybean seed tocopherols and (ii) to evaluate relationships...