This study mapped the adult-plant leaf rust resistance gene Lr22a in wheat using microsatellite markers (SSRs). Lr22a was previously introgressed from Aegilops tauschii into wheat. Comparing SSR alleles between the donor line and resistant backcross lines identified 2-5 markers co-introgressed with Lr22a spanning 9-20 cM. Testing these markers in an F2 population confirmed linkage of the closest marker GWM296 to Lr22a, located 2.9 cM away. GWM296 accurately predicted lines known to carry Lr22a and could be useful for marker-assisted selection of this resistance gene.
This Masters thesis defense presentation summarizes research identifying MH class IIβ alleles that may confer resistance or susceptibility to Bacterial Cold Water Disease (BCWD) in rainbow trout. The study genotyped MH class IIβ alleles in six families of trout that had been experimentally infected with the BCWD pathogen. Results found five alleles present among the families. The DAB*1001/DAB*0801 genotype had the lowest hazard ratio, suggesting an association with resistance to BCWD, although results were not statistically significant. Future work could examine MH class I alleles and innate immunity genes to better understand resistance in trout.
This study demonstrated a novel natural transformation mechanism in Actinobacillus actinomycetemcomitans (A.a.) that is independent of uptake signal sequences and the Tfox gene. The study showed that A.a. could be transformed with genomic and plasmid DNA present in microvesicles secreted into the growth medium of donor cells. This transformation occurred both in the presence and absence of components normally required for natural transformation in A.a. The results suggest outer membrane adhesion and fusion of donor microvesicles with recipient cells allows DNA delivery and homologous recombination. This novel mechanism could provide an easier method for genetically transforming A.a. compared to conventional techniques.
This document summarizes research on mutations in the genetic region that controls rapid lysis (rII group) in bacteriophage T4. The rII group includes many closely spaced mutants that produce different plaque morphologies on host bacteria. Recombination experiments between different rII mutants allow the detection of rare recombinant wild-type particles, enabling high resolution mapping of mutations within this genetic region. It is estimated that the resolution approaches distinguishing mutations just one nucleotide pair apart in the phage DNA. Preliminary results are presented on extending genetic mapping to the molecular scale using these hypermutable rII mutants.
This document summarizes a study that developed a reporter system in yeast to identify mutagens that preferentially damage single-stranded DNA (ssDNA). The system takes advantage of telomere uncapping in yeast, which exposes the reporter genes as long ssDNA overhangs. The researchers validated the system by expressing a human cytosine deaminase (APOBEC3G) that induced clusters of cytosine substitutions in the ssDNA. They then found that sulfites, at environmentally relevant concentrations, also induced large clusters of mutations specifically in the ssDNA by forming DNA adducts resistant to repair. This suggests sulfites may be a potent mutagen through ssDNA damage and highlights the importance of identifying such
This document summarizes a study that characterized resistance to the Russian wheat aphid (RWA) in the wheat line KRWA9. The researchers found that resistance segregated in a monogenic dominant manner. They used bulk segregant analysis with simple sequence repeat (SSR) markers between parental lines and resistant/susceptible bulks. One SSR marker on chromosome 7DS, Xgwm111, was closely linked to resistance with an R2 value of 85%. This marker provides opportunities for marker-assisted breeding to improve RWA resistance in wheat.
This document describes a study that developed a new method called amplified functional DNA restriction analysis (AFDRA) to analyze the diversity of catechol 2,3-dioxygenase (C23O) genes in soil bacteria. C23O genes code for enzymes important for degrading aromatic pollutants. The researchers used AFDRA to analyze C23O genes from reference strains and soil isolates. They found that AFDRA generated distinct restriction patterns that clustered the isolates into four groups, consistent with sequence analysis. AFDRA also allowed them to determine the predominant C23O gene variants present in environmental DNA extracts from soil samples. The study demonstrates that AFDRA provides a rapid way to assess functional gene diversity in cultures and
Poster64: QTL mapping of resitance to Thips palmi Karny in common bean (Phase...CIAT
This study identified quantitative trait loci (QTLs) for resistance to the bean flower thrips (Thrips palmi) in common beans. Recombinant inbred lines from a cross between resistant and susceptible bean varieties showed transgressive segregation for thrips resistance. Broad-sense heritability was higher for damage scores than reproductive adaptation scores. QTL mapping identified a major QTL for thrips resistance on linkage group B06 that explained up to 26.8% of variance. Joint interval mapping over multiple seasons revealed additional QTLs on linkage groups B02, B03, B06 and B08. Identification of thrips resistance genes can facilitate development of resistant bean varieties through marker-
This document summarizes research on the molecular mechanisms underlying inflammation caused by enteroaggregative Escherichia coli (EAEC) in the intestinal epithelium. EAEC causes chronic inflammation through the expression of aggregative adherence fimbriae (AAF) on its surface. In vitro studies showed that AAF expression triggers the basolateral release of the chemokine IL-8 from intestinal epithelial cells and the transmigration of polymorphonuclear neutrophils (PMNs). Further experiments identified that AAF expression from the prototype EAEC strains 042 and JM221, as well as the AAF/I and AAF/III fimbriae encoded on plasmids, are required for inducing PMN migration. Studies
This Masters thesis defense presentation summarizes research identifying MH class IIβ alleles that may confer resistance or susceptibility to Bacterial Cold Water Disease (BCWD) in rainbow trout. The study genotyped MH class IIβ alleles in six families of trout that had been experimentally infected with the BCWD pathogen. Results found five alleles present among the families. The DAB*1001/DAB*0801 genotype had the lowest hazard ratio, suggesting an association with resistance to BCWD, although results were not statistically significant. Future work could examine MH class I alleles and innate immunity genes to better understand resistance in trout.
This study demonstrated a novel natural transformation mechanism in Actinobacillus actinomycetemcomitans (A.a.) that is independent of uptake signal sequences and the Tfox gene. The study showed that A.a. could be transformed with genomic and plasmid DNA present in microvesicles secreted into the growth medium of donor cells. This transformation occurred both in the presence and absence of components normally required for natural transformation in A.a. The results suggest outer membrane adhesion and fusion of donor microvesicles with recipient cells allows DNA delivery and homologous recombination. This novel mechanism could provide an easier method for genetically transforming A.a. compared to conventional techniques.
This document summarizes research on mutations in the genetic region that controls rapid lysis (rII group) in bacteriophage T4. The rII group includes many closely spaced mutants that produce different plaque morphologies on host bacteria. Recombination experiments between different rII mutants allow the detection of rare recombinant wild-type particles, enabling high resolution mapping of mutations within this genetic region. It is estimated that the resolution approaches distinguishing mutations just one nucleotide pair apart in the phage DNA. Preliminary results are presented on extending genetic mapping to the molecular scale using these hypermutable rII mutants.
This document summarizes a study that developed a reporter system in yeast to identify mutagens that preferentially damage single-stranded DNA (ssDNA). The system takes advantage of telomere uncapping in yeast, which exposes the reporter genes as long ssDNA overhangs. The researchers validated the system by expressing a human cytosine deaminase (APOBEC3G) that induced clusters of cytosine substitutions in the ssDNA. They then found that sulfites, at environmentally relevant concentrations, also induced large clusters of mutations specifically in the ssDNA by forming DNA adducts resistant to repair. This suggests sulfites may be a potent mutagen through ssDNA damage and highlights the importance of identifying such
This document summarizes a study that characterized resistance to the Russian wheat aphid (RWA) in the wheat line KRWA9. The researchers found that resistance segregated in a monogenic dominant manner. They used bulk segregant analysis with simple sequence repeat (SSR) markers between parental lines and resistant/susceptible bulks. One SSR marker on chromosome 7DS, Xgwm111, was closely linked to resistance with an R2 value of 85%. This marker provides opportunities for marker-assisted breeding to improve RWA resistance in wheat.
This document describes a study that developed a new method called amplified functional DNA restriction analysis (AFDRA) to analyze the diversity of catechol 2,3-dioxygenase (C23O) genes in soil bacteria. C23O genes code for enzymes important for degrading aromatic pollutants. The researchers used AFDRA to analyze C23O genes from reference strains and soil isolates. They found that AFDRA generated distinct restriction patterns that clustered the isolates into four groups, consistent with sequence analysis. AFDRA also allowed them to determine the predominant C23O gene variants present in environmental DNA extracts from soil samples. The study demonstrates that AFDRA provides a rapid way to assess functional gene diversity in cultures and
Poster64: QTL mapping of resitance to Thips palmi Karny in common bean (Phase...CIAT
This study identified quantitative trait loci (QTLs) for resistance to the bean flower thrips (Thrips palmi) in common beans. Recombinant inbred lines from a cross between resistant and susceptible bean varieties showed transgressive segregation for thrips resistance. Broad-sense heritability was higher for damage scores than reproductive adaptation scores. QTL mapping identified a major QTL for thrips resistance on linkage group B06 that explained up to 26.8% of variance. Joint interval mapping over multiple seasons revealed additional QTLs on linkage groups B02, B03, B06 and B08. Identification of thrips resistance genes can facilitate development of resistant bean varieties through marker-
This document summarizes research on the molecular mechanisms underlying inflammation caused by enteroaggregative Escherichia coli (EAEC) in the intestinal epithelium. EAEC causes chronic inflammation through the expression of aggregative adherence fimbriae (AAF) on its surface. In vitro studies showed that AAF expression triggers the basolateral release of the chemokine IL-8 from intestinal epithelial cells and the transmigration of polymorphonuclear neutrophils (PMNs). Further experiments identified that AAF expression from the prototype EAEC strains 042 and JM221, as well as the AAF/I and AAF/III fimbriae encoded on plasmids, are required for inducing PMN migration. Studies
The document provides a history of genomics, beginning with Mendel's work in 1866 establishing the gene concept and laws of genetics. Key developments include the discovery of DNA in 1871, the chromosomal theory of inheritance in 1902, and the discovery of linkage in 1910. The structure of DNA was elucidated in the 1950s, leading to the development of recombinant DNA technology in the 1970s and DNA sequencing techniques in the 1970s-80s. The first whole genome of an organism was sequenced in 1995. More recent developments include next generation sequencing starting in 2005 and the advent of CRISPR/Cas9 genome editing in 2012. The document concludes with discussing the potential use of CRISPR to target genes in the diamondb
This document describes the development of 160 novel simple sequence repeat (SSR) markers in bitter gourd (Momordica charantia L.) through enriched genomic libraries. Genomic DNA from bitter gourd was used to construct libraries enriched for 10 different repeat motifs. Of the 3,072 clones screened, 93.7% contained microsatellite repeats. Unique primer pairs were designed and validated for 151 loci. Genetic diversity analysis of 51 loci among 54 accessions found 20% were polymorphic. The markers distinguished 15 Indian varieties and 78.4% were transferable across six Momordica species. The new SSR markers will be useful for genetic studies in bitter gourd.
Molecular marker to identify gynoecious lines in bitter gourdSwati Saxena
This document discusses the identification of molecular markers associated with the gynoecious trait in bitter gourd. Twenty-four gynoecious plants were screened using 200 RAPD and 28 ISSR markers. One ISSR primer amplified a 1000 base pair fragment present in all gynoecious plants but absent in two monoecious varieties. This fragment was repeatably amplified and could serve as a diagnostic marker for gynoecy, allowing identification of the trait at an early stage for hybrid seed production.
Polyploidy and molecular cytogenetics in crops: ECA conference Dublin July 2013Pat (JS) Heslop-Harrison
The document discusses using cytogenetics and molecular cytogenetics to study polyploidy signatures in crop karyotypes and breeding materials. Recent polyploidy can be revealed through hybridization and cytogenetics, while ancient polyploidy is revealed by sequencing. Understanding polyploidy is important for speciation, evolution and breeding. Different sequences classes evolve at different rates, and molecular cytogenetics can provide insights into recent rearrangements or duplications as well as ancient evolutionary polyploidy. The consequences and applications of studying polyploidy in crops are also discussed.
This study compares the transcriptomes of two switchgrass genotypes representing upland (VS16) and lowland (AP13) ecotypes. RNA sequencing was performed on leaf samples from both ecotypes, generating over 268 million reads. Over 90% of reads were mapped to the switchgrass reference genome. Differential expression analysis identified 6619 and 5369 differentially expressed genes in VS16 and AP13, respectively. Gene ontology and pathway analysis identified key genes involved in processes like C4 photosynthesis, photorespiration, and phenylpropanoid metabolism. The lowland ecotype AP13 showed higher expression of genes involved in photosynthesis, while the upland ecotype VS16 showed higher expression of genes related to ab
Marker Assisted Gene Pyramiding for Disease Resistance in RiceIndrapratap1
Why marker assisted gene pyramiding?
For traits that are simply inherited, but that are difficult or expensive to measure phenotypically, and/or that do not have a consistent phenotypic expression under specific selection conditions, marker-based selection is more effective than phenotypic selection.
Traits which are traditionally regarded as quantitative and not targeted by gene pyramiding program can be improved using gene pyramiding if major genes affecting the traits are identified.
Genes with very similar phenotypic effects, which are impossible or difficult to combine in single genotype using phenotypic selection, can be pyramided through marker assisted selection.
Markers provides a more effective option to control linkage drag and make the use of genes contained in unadapted resources easier.
Pyramiding is possible through conventional breeding but is extremely difficult or impossible at early generations..
DNA markers may facilitate selection because DNA marker assays are non destructive and markers for multiple specific genes/QTLs can be tested using a single DNA sample without phenotyping.
CONCLUSION:
• Molecular marker offer great scope for improving the efficiency of conventional plant breeding.
• Gene pyramiding may not be the most suitable strategy when many QTL with small effects control the trait and other methods such as marker-assisted recurrent selection should be considered.
• With MAS based gene pyramiding, it is now possible for breeder to conduct many rounds of selections in a year.
• Gene pyramiding with marker technology can integrate into existing plant breeding program all over the world to allow researchers to access, transfer and combine genes at a rate and with precision not previously possible.
• This will help breeders get around problems related to larger breeding populations, replications in diverse environments, and speed up the development of advance lines.
For further queries please contact at isag2010@gmail.com
This document summarizes research on the Scr74 gene family in Phytophthora infestans and how different variants of this gene are recognized in potato genotypes. The key points are:
1. 27 variants of the Scr74 effector gene were identified from 12 P. infestans isolates. 4 novel variants were cloned.
2. 13 amino acid sites in Scr74 were found to be under positive diversifying selection, indicating these sites are important for pathogen recognition.
3. 17 Scr74 variants were screened using PVX assays on 12 potato genotypes. Some genotypes had strong cell death responses to specific Scr74 variants, suggesting recognition of these variants.
4. Scr74 variants Scr74-A
This document describes the construction of two bacterial artificial chromosome (BAC) libraries containing over 1 gigabase of genomic DNA directly extracted from soil. The libraries were screened for various biochemical activities, identifying clones expressing antibacterial, lipase, amylase, nuclease, and hemolytic activities. Phylogenetic analysis of 16S rRNA gene sequences from one library revealed DNA from diverse microbial taxa. This cloning strategy allows genomic and functional genomic studies of uncultured soil microorganisms.
This document analyzed the genetic diversity of 50 Asian bitter gourd genotypes using morphological traits and molecular markers. Key findings:
1. Significant variation was found for yield and other traits based on morphological analysis, indicating genetic diversity. The highest yielding genotype was Sel-2.
2. Molecular analysis using RAPD and ISSR markers found high levels of polymorphism, with ISSR showing more polymorphic bands.
3. Cluster analyses based on morphological, RAPD, ISSR, and combined data grouped genotypes into clusters largely correlating with geographical origin and domestication status. The analyses demonstrate large genetic variability in the collection.
Gene pyramiding in tomato involves combining desirable genes from multiple parents into a single genotype to improve specific traits. It can enhance disease resistance, drought tolerance, yield, and fruit quality. One study found that pyramiding two virus resistance genes (Ty-2 and Ty-3) in tomato improved resistance to three viruses and had higher yields than lines with single genes. Another study found that pyramiding introgressions from wild tomato species S. pennellii improved drought tolerance, yield, soluble solids content, and the ratio of soluble solids to fruit weight. A third study showed that pyramiding quality trait genes increased antioxidant levels, soluble solids, and yield compared to lines with single introgressions. Gene
1. Recombinant DNA technology involves manipulating DNA from different species and combining them to form new recombinant DNA molecules.
2. Key steps include using restriction enzymes to cut DNA at specific sites, and DNA ligase to join DNA fragments together into vectors like plasmids.
3. The recombinant DNA can then be replicated in host cells like bacteria to produce multiple copies for analysis.
- The document discusses research on the cotton root-knot nematode (Meloidogyne incognita), an endoparasitic nematode that infects thousands of plant species and causes billions in crop damage worldwide.
- The research uses Arabidopsis thaliana plants, including mutant strains, to study the nematode's infection process. Mutant plants have mutations in an ABC transporter gene (At4g15320) involved in secreting chemicals that nematodes use to locate host plants.
- The goal is to see if the mutant transporter gene affects nematode infection rates compared to wild-type Arabidopsis. Results found the mutant was actually not a true mutant and showed similar nematode infection to the
Recombinant dna technology applicationsRamesh Gupta
Recombinant DNA technology has many applications in medicine including mapping genomes, producing proteins, diagnosing genetic diseases, and gene therapy. The human genome project mapped the entire human genome, finding it contains around 30,000 genes made up of 3.2 billion DNA base pairs. Recombinant DNA techniques allow mass production of human proteins like insulin to treat diseases. Genetic diseases can be diagnosed by analyzing changes in restriction fragment length patterns. DNA fingerprinting using variable tandem repeats is used in forensics and has helped solve criminal and parental identification cases. Gene therapy aims to treat genetic disorders by inserting normal genes to replace defective ones.
Recombinant DNA technology involves creating copies of DNA or genes by inserting them into vectors for introduction into host organisms. The key steps are: 1) isolating the gene of interest, 2) inserting it into a vector using restriction enzymes and DNA ligase, 3) transforming the recombinant DNA into a host cell, and 4) allowing the host to multiply and express the inserted gene. Common applications include producing recombinant human insulin, vaccines, and engineering crops for traits like herbicide or insect resistance.
This document discusses domestication, polyploidy, and genomics of crops and weeds. It notes that most major crop species were domesticated around 10,000 years ago, with a few more recently. Polyploidy, or whole genome duplication events, have also played an important role in crop evolution. The document examines genome sizes and components of various crop species, and notes that repetitive elements like transposons can make up large proportions of plant genomes. Differences in repetitive sequences between microspecies of dandelion are also discussed.
This document discusses the use of marker-assisted selection (MAS) in plant breeding. It begins by outlining some key challenges in plant breeding, then describes how MAS can accelerate the breeding cycle by allowing selection at early generations. It provides details on different types of MAS, including marker-assisted backcrossing, pyramiding of multiple genes, and early generation selection. Examples are given of MAS being used to introgress submergence tolerance and salinity tolerance genes into rice varieties. The document also discusses some reasons for the low impact of MAS to date, such as insufficient linkage between markers and traits.
This document summarizes a study that investigated the influence of HLA-DRB1 alleles on the production of antibodies against malaria antigens in individuals naturally infected with Plasmodium vivax in Brazil. The study found an association between HLA-DR3 and HLA-DR5 alleles and lack of antibody response to the amino terminal region of the circumsporozoite protein (CSP). It also found an association between HLA-DR3 and higher antibody response to merozoite surface protein 1 (MSP1). No significant associations were found between HLA-DRB1 alleles and antibody responses to other malaria antigens tested.
Thanveer Aslam - Tools of rDNA and its applications in agriculture Thanveer Aslam
1. Recombinant DNA technology uses restriction enzymes, DNA ligases, and vectors to introduce foreign genes into host organisms and alter their phenotypes.
2. The key tools of recombinant DNA technology are restriction enzymes, which cut DNA at specific recognition sequences; vectors like plasmids that carry foreign genes; and host organisms like E. coli bacteria that the foreign genes are introduced into.
3. Applications of biotechnology in agriculture include producing transgenic plants that are pest resistant, drought tolerant, or nutritionally enhanced to increase crop yields in a more sustainable way.
Cloning in gram positive bacteria by neelima sharma,neelima.sharma60@gmail.co...Neelima Sharma
This document discusses cloning in gram-positive bacteria like Bacillus subtilis. Key points include:
1. Vectors for cloning in B. subtilis are often derived from Staphylococcus aureus plasmids which can replicate in B. subtilis.
2. Hybrid plasmids that can replicate in both E. coli and B. subtilis are often used, allowing cloning in E. coli and expression in B. subtilis.
3. Recombinant DNA can be structurally unstable in B. subtilis, so vectors that replicate through the theta mechanism tend to be more stable.
This document discusses various methods of genetic recombination including transformation, conjugation, transduction, and protoplast fusion. It provides definitions and examples of key terms. Transformation involves the direct uptake of exogenous DNA by a cell. Conjugation is the transfer of genetic material between bacterial cells through direct contact. Transduction is the transfer of genes between bacteria mediated by bacteriophages. Protoplast fusion involves fusing plant protoplasts using electric shock or chemicals to produce somatic hybrid plants. The document also discusses applications of these techniques such as gene cloning, production of monoclonal antibodies, and genetic engineering.
The document summarizes research on sequencing part of the ribosomal RNA coding region and determining the secondary structure of the 25S rRNA of Candida albicans. Key findings include:
- A rDNA cistron from C. albicans strain WO-1 was cloned and sequencing revealed the ITS1, ITS2, 5.8S rDNA and 25S rDNA coding regions.
- The C. albicans ITS regions are shorter than those of most other eukaryotes.
- The 5.8S and 25S rDNA sequences were used to model the secondary structure, which was compared to other species.
- Variable regions in the 25S r
The document summarizes research on pleiotropic adult plant resistance (PAPR) loci in wheat. Key points:
1. CIMMYT has conducted PAPR research since the 1970s, identifying loci such as Lr34, Lr46, and Lr67 that confer resistance to multiple diseases.
2. Studies mapped additional PAPR QTL in various wheat populations and identified markers for genes like Lr46, Sr2, and Yr54 useful for marker-assisted selection.
3. Research involves fine mapping genes, identifying deletion mutants, and understanding resistance mechanisms to improve durability and pyramide genes in wheat breeding.
4. An international shuttle breeding program
The document provides a history of genomics, beginning with Mendel's work in 1866 establishing the gene concept and laws of genetics. Key developments include the discovery of DNA in 1871, the chromosomal theory of inheritance in 1902, and the discovery of linkage in 1910. The structure of DNA was elucidated in the 1950s, leading to the development of recombinant DNA technology in the 1970s and DNA sequencing techniques in the 1970s-80s. The first whole genome of an organism was sequenced in 1995. More recent developments include next generation sequencing starting in 2005 and the advent of CRISPR/Cas9 genome editing in 2012. The document concludes with discussing the potential use of CRISPR to target genes in the diamondb
This document describes the development of 160 novel simple sequence repeat (SSR) markers in bitter gourd (Momordica charantia L.) through enriched genomic libraries. Genomic DNA from bitter gourd was used to construct libraries enriched for 10 different repeat motifs. Of the 3,072 clones screened, 93.7% contained microsatellite repeats. Unique primer pairs were designed and validated for 151 loci. Genetic diversity analysis of 51 loci among 54 accessions found 20% were polymorphic. The markers distinguished 15 Indian varieties and 78.4% were transferable across six Momordica species. The new SSR markers will be useful for genetic studies in bitter gourd.
Molecular marker to identify gynoecious lines in bitter gourdSwati Saxena
This document discusses the identification of molecular markers associated with the gynoecious trait in bitter gourd. Twenty-four gynoecious plants were screened using 200 RAPD and 28 ISSR markers. One ISSR primer amplified a 1000 base pair fragment present in all gynoecious plants but absent in two monoecious varieties. This fragment was repeatably amplified and could serve as a diagnostic marker for gynoecy, allowing identification of the trait at an early stage for hybrid seed production.
Polyploidy and molecular cytogenetics in crops: ECA conference Dublin July 2013Pat (JS) Heslop-Harrison
The document discusses using cytogenetics and molecular cytogenetics to study polyploidy signatures in crop karyotypes and breeding materials. Recent polyploidy can be revealed through hybridization and cytogenetics, while ancient polyploidy is revealed by sequencing. Understanding polyploidy is important for speciation, evolution and breeding. Different sequences classes evolve at different rates, and molecular cytogenetics can provide insights into recent rearrangements or duplications as well as ancient evolutionary polyploidy. The consequences and applications of studying polyploidy in crops are also discussed.
This study compares the transcriptomes of two switchgrass genotypes representing upland (VS16) and lowland (AP13) ecotypes. RNA sequencing was performed on leaf samples from both ecotypes, generating over 268 million reads. Over 90% of reads were mapped to the switchgrass reference genome. Differential expression analysis identified 6619 and 5369 differentially expressed genes in VS16 and AP13, respectively. Gene ontology and pathway analysis identified key genes involved in processes like C4 photosynthesis, photorespiration, and phenylpropanoid metabolism. The lowland ecotype AP13 showed higher expression of genes involved in photosynthesis, while the upland ecotype VS16 showed higher expression of genes related to ab
Marker Assisted Gene Pyramiding for Disease Resistance in RiceIndrapratap1
Why marker assisted gene pyramiding?
For traits that are simply inherited, but that are difficult or expensive to measure phenotypically, and/or that do not have a consistent phenotypic expression under specific selection conditions, marker-based selection is more effective than phenotypic selection.
Traits which are traditionally regarded as quantitative and not targeted by gene pyramiding program can be improved using gene pyramiding if major genes affecting the traits are identified.
Genes with very similar phenotypic effects, which are impossible or difficult to combine in single genotype using phenotypic selection, can be pyramided through marker assisted selection.
Markers provides a more effective option to control linkage drag and make the use of genes contained in unadapted resources easier.
Pyramiding is possible through conventional breeding but is extremely difficult or impossible at early generations..
DNA markers may facilitate selection because DNA marker assays are non destructive and markers for multiple specific genes/QTLs can be tested using a single DNA sample without phenotyping.
CONCLUSION:
• Molecular marker offer great scope for improving the efficiency of conventional plant breeding.
• Gene pyramiding may not be the most suitable strategy when many QTL with small effects control the trait and other methods such as marker-assisted recurrent selection should be considered.
• With MAS based gene pyramiding, it is now possible for breeder to conduct many rounds of selections in a year.
• Gene pyramiding with marker technology can integrate into existing plant breeding program all over the world to allow researchers to access, transfer and combine genes at a rate and with precision not previously possible.
• This will help breeders get around problems related to larger breeding populations, replications in diverse environments, and speed up the development of advance lines.
For further queries please contact at isag2010@gmail.com
This document summarizes research on the Scr74 gene family in Phytophthora infestans and how different variants of this gene are recognized in potato genotypes. The key points are:
1. 27 variants of the Scr74 effector gene were identified from 12 P. infestans isolates. 4 novel variants were cloned.
2. 13 amino acid sites in Scr74 were found to be under positive diversifying selection, indicating these sites are important for pathogen recognition.
3. 17 Scr74 variants were screened using PVX assays on 12 potato genotypes. Some genotypes had strong cell death responses to specific Scr74 variants, suggesting recognition of these variants.
4. Scr74 variants Scr74-A
This document describes the construction of two bacterial artificial chromosome (BAC) libraries containing over 1 gigabase of genomic DNA directly extracted from soil. The libraries were screened for various biochemical activities, identifying clones expressing antibacterial, lipase, amylase, nuclease, and hemolytic activities. Phylogenetic analysis of 16S rRNA gene sequences from one library revealed DNA from diverse microbial taxa. This cloning strategy allows genomic and functional genomic studies of uncultured soil microorganisms.
This document analyzed the genetic diversity of 50 Asian bitter gourd genotypes using morphological traits and molecular markers. Key findings:
1. Significant variation was found for yield and other traits based on morphological analysis, indicating genetic diversity. The highest yielding genotype was Sel-2.
2. Molecular analysis using RAPD and ISSR markers found high levels of polymorphism, with ISSR showing more polymorphic bands.
3. Cluster analyses based on morphological, RAPD, ISSR, and combined data grouped genotypes into clusters largely correlating with geographical origin and domestication status. The analyses demonstrate large genetic variability in the collection.
Gene pyramiding in tomato involves combining desirable genes from multiple parents into a single genotype to improve specific traits. It can enhance disease resistance, drought tolerance, yield, and fruit quality. One study found that pyramiding two virus resistance genes (Ty-2 and Ty-3) in tomato improved resistance to three viruses and had higher yields than lines with single genes. Another study found that pyramiding introgressions from wild tomato species S. pennellii improved drought tolerance, yield, soluble solids content, and the ratio of soluble solids to fruit weight. A third study showed that pyramiding quality trait genes increased antioxidant levels, soluble solids, and yield compared to lines with single introgressions. Gene
1. Recombinant DNA technology involves manipulating DNA from different species and combining them to form new recombinant DNA molecules.
2. Key steps include using restriction enzymes to cut DNA at specific sites, and DNA ligase to join DNA fragments together into vectors like plasmids.
3. The recombinant DNA can then be replicated in host cells like bacteria to produce multiple copies for analysis.
- The document discusses research on the cotton root-knot nematode (Meloidogyne incognita), an endoparasitic nematode that infects thousands of plant species and causes billions in crop damage worldwide.
- The research uses Arabidopsis thaliana plants, including mutant strains, to study the nematode's infection process. Mutant plants have mutations in an ABC transporter gene (At4g15320) involved in secreting chemicals that nematodes use to locate host plants.
- The goal is to see if the mutant transporter gene affects nematode infection rates compared to wild-type Arabidopsis. Results found the mutant was actually not a true mutant and showed similar nematode infection to the
Recombinant dna technology applicationsRamesh Gupta
Recombinant DNA technology has many applications in medicine including mapping genomes, producing proteins, diagnosing genetic diseases, and gene therapy. The human genome project mapped the entire human genome, finding it contains around 30,000 genes made up of 3.2 billion DNA base pairs. Recombinant DNA techniques allow mass production of human proteins like insulin to treat diseases. Genetic diseases can be diagnosed by analyzing changes in restriction fragment length patterns. DNA fingerprinting using variable tandem repeats is used in forensics and has helped solve criminal and parental identification cases. Gene therapy aims to treat genetic disorders by inserting normal genes to replace defective ones.
Recombinant DNA technology involves creating copies of DNA or genes by inserting them into vectors for introduction into host organisms. The key steps are: 1) isolating the gene of interest, 2) inserting it into a vector using restriction enzymes and DNA ligase, 3) transforming the recombinant DNA into a host cell, and 4) allowing the host to multiply and express the inserted gene. Common applications include producing recombinant human insulin, vaccines, and engineering crops for traits like herbicide or insect resistance.
This document discusses domestication, polyploidy, and genomics of crops and weeds. It notes that most major crop species were domesticated around 10,000 years ago, with a few more recently. Polyploidy, or whole genome duplication events, have also played an important role in crop evolution. The document examines genome sizes and components of various crop species, and notes that repetitive elements like transposons can make up large proportions of plant genomes. Differences in repetitive sequences between microspecies of dandelion are also discussed.
This document discusses the use of marker-assisted selection (MAS) in plant breeding. It begins by outlining some key challenges in plant breeding, then describes how MAS can accelerate the breeding cycle by allowing selection at early generations. It provides details on different types of MAS, including marker-assisted backcrossing, pyramiding of multiple genes, and early generation selection. Examples are given of MAS being used to introgress submergence tolerance and salinity tolerance genes into rice varieties. The document also discusses some reasons for the low impact of MAS to date, such as insufficient linkage between markers and traits.
This document summarizes a study that investigated the influence of HLA-DRB1 alleles on the production of antibodies against malaria antigens in individuals naturally infected with Plasmodium vivax in Brazil. The study found an association between HLA-DR3 and HLA-DR5 alleles and lack of antibody response to the amino terminal region of the circumsporozoite protein (CSP). It also found an association between HLA-DR3 and higher antibody response to merozoite surface protein 1 (MSP1). No significant associations were found between HLA-DRB1 alleles and antibody responses to other malaria antigens tested.
Thanveer Aslam - Tools of rDNA and its applications in agriculture Thanveer Aslam
1. Recombinant DNA technology uses restriction enzymes, DNA ligases, and vectors to introduce foreign genes into host organisms and alter their phenotypes.
2. The key tools of recombinant DNA technology are restriction enzymes, which cut DNA at specific recognition sequences; vectors like plasmids that carry foreign genes; and host organisms like E. coli bacteria that the foreign genes are introduced into.
3. Applications of biotechnology in agriculture include producing transgenic plants that are pest resistant, drought tolerant, or nutritionally enhanced to increase crop yields in a more sustainable way.
Cloning in gram positive bacteria by neelima sharma,neelima.sharma60@gmail.co...Neelima Sharma
This document discusses cloning in gram-positive bacteria like Bacillus subtilis. Key points include:
1. Vectors for cloning in B. subtilis are often derived from Staphylococcus aureus plasmids which can replicate in B. subtilis.
2. Hybrid plasmids that can replicate in both E. coli and B. subtilis are often used, allowing cloning in E. coli and expression in B. subtilis.
3. Recombinant DNA can be structurally unstable in B. subtilis, so vectors that replicate through the theta mechanism tend to be more stable.
This document discusses various methods of genetic recombination including transformation, conjugation, transduction, and protoplast fusion. It provides definitions and examples of key terms. Transformation involves the direct uptake of exogenous DNA by a cell. Conjugation is the transfer of genetic material between bacterial cells through direct contact. Transduction is the transfer of genes between bacteria mediated by bacteriophages. Protoplast fusion involves fusing plant protoplasts using electric shock or chemicals to produce somatic hybrid plants. The document also discusses applications of these techniques such as gene cloning, production of monoclonal antibodies, and genetic engineering.
The document summarizes research on sequencing part of the ribosomal RNA coding region and determining the secondary structure of the 25S rRNA of Candida albicans. Key findings include:
- A rDNA cistron from C. albicans strain WO-1 was cloned and sequencing revealed the ITS1, ITS2, 5.8S rDNA and 25S rDNA coding regions.
- The C. albicans ITS regions are shorter than those of most other eukaryotes.
- The 5.8S and 25S rDNA sequences were used to model the secondary structure, which was compared to other species.
- Variable regions in the 25S r
The document summarizes research on pleiotropic adult plant resistance (PAPR) loci in wheat. Key points:
1. CIMMYT has conducted PAPR research since the 1970s, identifying loci such as Lr34, Lr46, and Lr67 that confer resistance to multiple diseases.
2. Studies mapped additional PAPR QTL in various wheat populations and identified markers for genes like Lr46, Sr2, and Yr54 useful for marker-assisted selection.
3. Research involves fine mapping genes, identifying deletion mutants, and understanding resistance mechanisms to improve durability and pyramide genes in wheat breeding.
4. An international shuttle breeding program
This document presents the complete small subunit ribosomal RNA (SSU rRNA) sequences of Giardia ardeae, G. muris, G. duodenalis, and the diplomonad Hexamita. The sequences are compared to analyze phylogenetic relationships. The Giardia sequences range from 1432 to 1453 nucleotides in length, while Hexamita's is 1550 nucleotides. Secondary structure analysis reveals both typically eukaryotic and variable regions. A phylogenetic tree groups the Giardia species separately from Hexamita and Vairimorpha, suggesting they represent a separate kingdom within the domain Eucarya.
4 16s rna partial sequencing of isolated strains of metal resistant bacteria ...BIOLOGICAL FORUM
ABSTRACT: Elaeocarpus is a diverse genus within the family Elaeocarpaceae. There is wide distribution of Elaeocarpus in the world among the tropical and subtropical climatic zones. In India, rudraksha (Elaeocarpus sphaericus) has important medicinal and religious values and its history dates back to ancient times. However, the evolutionary relationship of rudraksha with other species of Elaeocarpus is not much explored specially at the molecular and phylogenetic level. The present study establishes evolutionary relationship between rudraksha and other species of Elaeocarpus through phylogenetic algorithms like neighbor joining and maximum likelihood. Thirty species of Elaeocarpus found in the Indo-Australian region were grouped into clusters based on the rDNA and ITS sequence based phylogenetic analysis. This studies paves a way for further studies on evolutionary history of rudraksha with respect to other species of Elaeocarpus and their geographical distribution.
The document describes an experiment to construct a double mutant yeast strain deficient in both interstrand crosslink repair genes and homologous recombination repair genes. Yeast strains with single mutations in these genes were mated and the progeny were screened to isolate strains with mutations in both genes. Hundreds of progeny colonies from three crosses were tested for growth on selective media and after mating with tester strains to identify eight candidate double mutant strains.
1. DREB genes play an important role in improving crop tolerance to stresses like drought, salt, and cold. DREB transcription factors regulate stress-responsive genes allowing plants to adapt.
2. Case studies showed overexpression of DREB genes enhanced stress tolerance in crops like rice and sugarcane. Co-transformation with DREB and other stress genes improved tolerance more than single DREB genes.
3. DREB genes respond differently to various stresses. DREB1 genes respond mainly to cold while DREB2 genes respond to dehydration and heat. Proper expression analysis of DREB genes is important for abiotic stress tolerance in transgenic crops.
Yellow rust seminar by Priyanka (Phd Scholar Genetics and Plant Breeding CSK ...Priyanka Guleria
This seminar explains about the yellow rust disease of wheat: Its genetics and prevention methods as well as molecular techniques to combat yellow rust
The Lr34 gene in wheat has provided effective resistance against rust for over 100 years. It confers partial and durable resistance by prolonging the latency period and reducing spore production. Lr34 is not race-specific and also confers resistance to other pathogens. It encodes an ATP-binding cassette (ABC) transporter protein and differs by only two amino acids from susceptible alleles. Transgenic wheat with Lr34 shows complementation of resistance, though the genetic background can influence effects. Lr34's durable resistance is likely due to its ability to transport antimicrobial compounds or prime defense responses through its function as an ABC transporter.
This study characterized the plant pathogen Verticillium dahliae using genetic analysis techniques. Random amplified polymorphic DNA (RAPD) analysis of 34 isolates from different host plants and geographic regions identified 79 distinct genetic markers that clustered the isolates into two main groups. One group consisted primarily of isolates from oilseed rape, while the other comprised isolates from a diverse range of host plants. Sequencing of the 18S ribosomal RNA gene integrated V. dahliae into the sexual system of filamentous ascomycetes fungi. The study investigated genetic diversity and phylogenetic position of V. dahliae.
This document summarizes research on gene duplications in Drosophila flies and humans. It finds that tandem gene duplications are more common around centromeres in Drosophila yakuba flies. In D. simulans flies, there is an excess of high-frequency duplications on the X chromosome compared to autosomes, suggesting widespread selection for duplications on the D. simulans X chromosome. The document also reviews cases of partial gene duplications associated with human diseases, finding they can result in novel gene structures and expression patterns with implications for disease.
Molecular tagging of genes involves identifying existing DNA or introducing new DNA to function as a tag or label for the gene of interest. There are four main strategies for gene tagging: marker-based tagging, transposon tagging, T-DNA tagging, and epitope tagging. Marker-based tagging uses molecular markers tightly linked to important traits to assist in plant breeding programs. Transposon tagging relies on transposons, which can move within the genome, to provide a DNA tag that can then be used to identify adjacent DNA sequences and genes.
This document summarizes a seminar on doubled haploids (DH). It defines a DH as an individual with a doubled set of chromosomes from a haploid cell. It discusses the history of DH development, including early work in the 1920s. It also covers methods for producing haploids, identifying haploids, doubling chromosomes, and applications of DHs in plant breeding like QTL mapping, backcrossing, hybrid sorting, and cultivar development. DHs allow fixing of traits in one or two generations, faster development of pure lines and cultivars compared to conventional methods.
Breeding for Abiotic Stress Tolerance in Legumesasmat ara
This document summarizes a seminar on breeding for abiotic stress tolerance in legumes. It discusses various breeding strategies, including field testing, phenotyping traits, screening genes and QTLs, and using transcriptomics, proteomics, and microbiome approaches. It also describes some legume varieties bred for stress tolerance. Additionally, it outlines physiological, molecular, and genomic approaches for improving stress tolerance, such as escape mechanisms, dehydration avoidance, dehydration tolerance, signaling pathways, transgenics, molecular markers, QTL analysis, and genome editing using CRISPR-Cas9.
This document summarizes research on cloning rust resistance genes from wheat and developing gene pyramids via genetic engineering. Key points include:
- Researchers at the University of Minnesota and other institutions are working to clone multiple rust resistance genes from wheat including Sr2, Sr22, Sr33, Sr35, Sr46, Sr50 and Lr67.
- Cloned genes like Lr34/Yr18, Yr36, and others can be stacked together in transgenic cassettes to provide pyramided resistance in a single locus.
- Preliminary work has successfully stacked two or three resistance genes in transgenic wheat.
- Further work will continue cloning additional genes, validating gene function through transformation, and
Plant disease resistance genes: current status and future directions.RonikaThakur
Agriculture plays a key role to ensure the food security. But plant diseases hinder the crop production by reducing yield to much extent. To overcome this problem it is crucial to understand plant disease resistance genes which prevent growth of plant pathogens thereby reducing the yield loss.
This document proposes establishing a new order, Thoreales, for the freshwater red algal family Thoreaceae based on phylogenetic and ultrastructural evidence. The study examines specimens of Nemalionopsis and Thorea using gene sequencing and electron microscopy of pit plugs. Phylogenetic trees produced from rbcL and 18S rRNA gene sequences strongly support Thoreaceae as a distinct clade separate from other families in the order Batrachospermales. Pit plug ultrastructure also differs from descriptions in Batrachospermales by having two cap layers, with the outer layer usually plate-like. The evidence indicates Thoreaceae has been misclassified in Batrachospermales and warrants being placed in its own order,
This document presents a study that mapped quantitative trait loci (QTL) controlling powdery mildew resistance in a recombinant inbred line population of mungbean. The study identified two QTLs, a major QTL (qPMR-2) explaining 57.81% of phenotypic variation and a minor QTL (qPMR-1) explaining 20.10% of variation, that control resistance on different linkage groups. Flanking markers for each QTL were identified that can be used for marker-assisted selection of mungbean lines with improved powdery mildew resistance.
This study aimed to determine the phylogenetic relationships between 17 species of sea cucumbers found in Malaysia using sequences of the 16S mitochondrial rRNA gene. Phylogenetic trees were constructed using neighbor joining, maximum parsimony, and maximum likelihood methods. The trees showed five main genera of sea cucumbers were present: Molpadia, Holothuria, Stichopus, Bohadschia, and Actinopyga. However, one species of Holothuria was found to be outside of the Holothuria group, making it paraphyletic. Further studies with more samples and different mitochondrial DNA genes are needed to better understand the molecular phylogeny of sea cucumbers.
Identification of Candidate Genes for Drought Stress in MaizeCIMMYT
1) The document summarizes research on identifying genes and regulatory mechanisms related to drought tolerance in maize.
2) Whole genome resequencing of 16 maize inbred lines identified candidate genes containing non-synonymous SNPs associated with drought tolerance.
3) Analysis of natural antisense transcripts (NATs) in maize found many NAT pairs responsive to drought stress, with concordant or discordant expression patterns between sense and antisense transcripts.
4) Experimental validation confirmed the expression of selected NAT pairs and their response to drought stress. The role of the ZmNAC48-cis-NATZmNAC48 pair in the drought response was further investigated.
The document discusses a study on MRSA 252, a methicillin-resistant Staphylococcus aureus strain. It aims to construct a prophage-free host strain of MRSA 252 that can propagate lytic bacteriophages. 31 mutant strains of MRSA 252 were created using mitomycin C to induce prophages. Prophage screening using PCR found that mutations 7 and 8 did not contain the φSa2 and φSa3 prophages. Most mutant strains were susceptible to lytic phages in spot tests, but were resistant to some phages and high dilutions of others. Mutations 7 and 8 were resistant to all tested phages. The attempt to mobilize prophages from M
This document provides information about the TRANZFOR project, which aims to strengthen research collaboration on forestry and climate change between the EU and Australia-New Zealand through staff exchanges. At the mid-point of the project, 25 exchanges had been completed out of a planned 75, representing one-third of the total expected person-months of exchange. Exchanges involved researchers working on topics across the five work packages of the project, including genomics and tree breeding, forest modeling, environmental services, risk assessment, and bioenergy. Ten joint publications were in preparation, and five of the planned milestones had been achieved, including the establishment of a project website.
This document summarizes the TRANZFOR project, which aims to improve understanding of how forests and forestry can adapt to climate change. It discusses the project's work packages focusing on genomics, forest modeling, environmental services, risk assessment, and bioenergy. It provides examples of research conducted under each work package. It also outlines TRANZFOR's past work and potential future areas of research, such as forest mortality, carbon cycling, genetics by environment interactions, and native forest resilience.
The National Institute for Agronomic Research (INRA) was established in 1946 in France. It is the largest agricultural research organization in Europe with nearly 9,000 staff and a budget of 680 million euros. INRA conducts research in six major areas: environment and rural areas, human nutrition and food safety, quality of agricultural products, understanding living organisms, agricultural practices and systems, and social sciences. It focuses on sustainable agriculture, nutrition and health, and the environment. INRA collaborates extensively with other research organizations, universities, and industry partners in France and internationally.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms for those who already suffer from conditions like anxiety and depression.
Pushing the limits of ePRTC: 100ns holdover for 100 daysAdtran
At WSTS 2024, Alon Stern explored the topic of parametric holdover and explained how recent research findings can be implemented in real-world PNT networks to achieve 100 nanoseconds of accuracy for up to 100 days.
Driving Business Innovation: Latest Generative AI Advancements & Success StorySafe Software
Are you ready to revolutionize how you handle data? Join us for a webinar where we’ll bring you up to speed with the latest advancements in Generative AI technology and discover how leveraging FME with tools from giants like Google Gemini, Amazon, and Microsoft OpenAI can supercharge your workflow efficiency.
During the hour, we’ll take you through:
Guest Speaker Segment with Hannah Barrington: Dive into the world of dynamic real estate marketing with Hannah, the Marketing Manager at Workspace Group. Hear firsthand how their team generates engaging descriptions for thousands of office units by integrating diverse data sources—from PDF floorplans to web pages—using FME transformers, like OpenAIVisionConnector and AnthropicVisionConnector. This use case will show you how GenAI can streamline content creation for marketing across the board.
Ollama Use Case: Learn how Scenario Specialist Dmitri Bagh has utilized Ollama within FME to input data, create custom models, and enhance security protocols. This segment will include demos to illustrate the full capabilities of FME in AI-driven processes.
Custom AI Models: Discover how to leverage FME to build personalized AI models using your data. Whether it’s populating a model with local data for added security or integrating public AI tools, find out how FME facilitates a versatile and secure approach to AI.
We’ll wrap up with a live Q&A session where you can engage with our experts on your specific use cases, and learn more about optimizing your data workflows with AI.
This webinar is ideal for professionals seeking to harness the power of AI within their data management systems while ensuring high levels of customization and security. Whether you're a novice or an expert, gain actionable insights and strategies to elevate your data processes. Join us to see how FME and AI can revolutionize how you work with data!
Removing Uninteresting Bytes in Software FuzzingAftab Hussain
Imagine a world where software fuzzing, the process of mutating bytes in test seeds to uncover hidden and erroneous program behaviors, becomes faster and more effective. A lot depends on the initial seeds, which can significantly dictate the trajectory of a fuzzing campaign, particularly in terms of how long it takes to uncover interesting behaviour in your code. We introduce DIAR, a technique designed to speedup fuzzing campaigns by pinpointing and eliminating those uninteresting bytes in the seeds. Picture this: instead of wasting valuable resources on meaningless mutations in large, bloated seeds, DIAR removes the unnecessary bytes, streamlining the entire process.
In this work, we equipped AFL, a popular fuzzer, with DIAR and examined two critical Linux libraries -- Libxml's xmllint, a tool for parsing xml documents, and Binutil's readelf, an essential debugging and security analysis command-line tool used to display detailed information about ELF (Executable and Linkable Format). Our preliminary results show that AFL+DIAR does not only discover new paths more quickly but also achieves higher coverage overall. This work thus showcases how starting with lean and optimized seeds can lead to faster, more comprehensive fuzzing campaigns -- and DIAR helps you find such seeds.
- These are slides of the talk given at IEEE International Conference on Software Testing Verification and Validation Workshop, ICSTW 2022.
Best 20 SEO Techniques To Improve Website Visibility In SERPPixlogix Infotech
Boost your website's visibility with proven SEO techniques! Our latest blog dives into essential strategies to enhance your online presence, increase traffic, and rank higher on search engines. From keyword optimization to quality content creation, learn how to make your site stand out in the crowded digital landscape. Discover actionable tips and expert insights to elevate your SEO game.
For the full video of this presentation, please visit: https://www.edge-ai-vision.com/2024/06/building-and-scaling-ai-applications-with-the-nx-ai-manager-a-presentation-from-network-optix/
Robin van Emden, Senior Director of Data Science at Network Optix, presents the “Building and Scaling AI Applications with the Nx AI Manager,” tutorial at the May 2024 Embedded Vision Summit.
In this presentation, van Emden covers the basics of scaling edge AI solutions using the Nx tool kit. He emphasizes the process of developing AI models and deploying them globally. He also showcases the conversion of AI models and the creation of effective edge AI pipelines, with a focus on pre-processing, model conversion, selecting the appropriate inference engine for the target hardware and post-processing.
van Emden shows how Nx can simplify the developer’s life and facilitate a rapid transition from concept to production-ready applications.He provides valuable insights into developing scalable and efficient edge AI solutions, with a strong focus on practical implementation.
Cosa hanno in comune un mattoncino Lego e la backdoor XZ?Speck&Tech
ABSTRACT: A prima vista, un mattoncino Lego e la backdoor XZ potrebbero avere in comune il fatto di essere entrambi blocchi di costruzione, o dipendenze di progetti creativi e software. La realtà è che un mattoncino Lego e il caso della backdoor XZ hanno molto di più di tutto ciò in comune.
Partecipate alla presentazione per immergervi in una storia di interoperabilità, standard e formati aperti, per poi discutere del ruolo importante che i contributori hanno in una comunità open source sostenibile.
BIO: Sostenitrice del software libero e dei formati standard e aperti. È stata un membro attivo dei progetti Fedora e openSUSE e ha co-fondato l'Associazione LibreItalia dove è stata coinvolta in diversi eventi, migrazioni e formazione relativi a LibreOffice. In precedenza ha lavorato a migrazioni e corsi di formazione su LibreOffice per diverse amministrazioni pubbliche e privati. Da gennaio 2020 lavora in SUSE come Software Release Engineer per Uyuni e SUSE Manager e quando non segue la sua passione per i computer e per Geeko coltiva la sua curiosità per l'astronomia (da cui deriva il suo nickname deneb_alpha).
Communications Mining Series - Zero to Hero - Session 1DianaGray10
This session provides introduction to UiPath Communication Mining, importance and platform overview. You will acquire a good understand of the phases in Communication Mining as we go over the platform with you. Topics covered:
• Communication Mining Overview
• Why is it important?
• How can it help today’s business and the benefits
• Phases in Communication Mining
• Demo on Platform overview
• Q/A
HCL Notes and Domino License Cost Reduction in the World of DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-and-domino-license-cost-reduction-in-the-world-of-dlau/
The introduction of DLAU and the CCB & CCX licensing model caused quite a stir in the HCL community. As a Notes and Domino customer, you may have faced challenges with unexpected user counts and license costs. You probably have questions on how this new licensing approach works and how to benefit from it. Most importantly, you likely have budget constraints and want to save money where possible. Don’t worry, we can help with all of this!
We’ll show you how to fix common misconfigurations that cause higher-than-expected user counts, and how to identify accounts which you can deactivate to save money. There are also frequent patterns that can cause unnecessary cost, like using a person document instead of a mail-in for shared mailboxes. We’ll provide examples and solutions for those as well. And naturally we’ll explain the new licensing model.
Join HCL Ambassador Marc Thomas in this webinar with a special guest appearance from Franz Walder. It will give you the tools and know-how to stay on top of what is going on with Domino licensing. You will be able lower your cost through an optimized configuration and keep it low going forward.
These topics will be covered
- Reducing license cost by finding and fixing misconfigurations and superfluous accounts
- How do CCB and CCX licenses really work?
- Understanding the DLAU tool and how to best utilize it
- Tips for common problem areas, like team mailboxes, functional/test users, etc
- Practical examples and best practices to implement right away
Essentials of Automations: The Art of Triggers and Actions in FMESafe Software
In this second installment of our Essentials of Automations webinar series, we’ll explore the landscape of triggers and actions, guiding you through the nuances of authoring and adapting workspaces for seamless automations. Gain an understanding of the full spectrum of triggers and actions available in FME, empowering you to enhance your workspaces for efficient automation.
We’ll kick things off by showcasing the most commonly used event-based triggers, introducing you to various automation workflows like manual triggers, schedules, directory watchers, and more. Plus, see how these elements play out in real scenarios.
Whether you’re tweaking your current setup or building from the ground up, this session will arm you with the tools and insights needed to transform your FME usage into a powerhouse of productivity. Join us to discover effective strategies that simplify complex processes, enhancing your productivity and transforming your data management practices with FME. Let’s turn complexity into clarity and make your workspaces work wonders!
Climate Impact of Software Testing at Nordic Testing DaysKari Kakkonen
My slides at Nordic Testing Days 6.6.2024
Climate impact / sustainability of software testing discussed on the talk. ICT and testing must carry their part of global responsibility to help with the climat warming. We can minimize the carbon footprint but we can also have a carbon handprint, a positive impact on the climate. Quality characteristics can be added with sustainability, and then measured continuously. Test environments can be used less, and in smaller scale and on demand. Test techniques can be used in optimizing or minimizing number of tests. Test automation can be used to speed up testing.
Sudheer Mechineni, Head of Application Frameworks, Standard Chartered Bank
Discover how Standard Chartered Bank harnessed the power of Neo4j to transform complex data access challenges into a dynamic, scalable graph database solution. This keynote will cover their journey from initial adoption to deploying a fully automated, enterprise-grade causal cluster, highlighting key strategies for modelling organisational changes and ensuring robust disaster recovery. Learn how these innovations have not only enhanced Standard Chartered Bank’s data infrastructure but also positioned them as pioneers in the banking sector’s adoption of graph technology.
Building Production Ready Search Pipelines with Spark and MilvusZilliz
Spark is the widely used ETL tool for processing, indexing and ingesting data to serving stack for search. Milvus is the production-ready open-source vector database. In this talk we will show how to use Spark to process unstructured data to extract vector representations, and push the vectors to Milvus vector database for search serving.
GraphSummit Singapore | The Art of the Possible with Graph - Q2 2024Neo4j
Neha Bajwa, Vice President of Product Marketing, Neo4j
Join us as we explore breakthrough innovations enabled by interconnected data and AI. Discover firsthand how organizations use relationships in data to uncover contextual insights and solve our most pressing challenges – from optimizing supply chains, detecting fraud, and improving customer experiences to accelerating drug discoveries.
How to Get CNIC Information System with Paksim Ga.pptxdanishmna97
Pakdata Cf is a groundbreaking system designed to streamline and facilitate access to CNIC information. This innovative platform leverages advanced technology to provide users with efficient and secure access to their CNIC details.
UiPath Test Automation using UiPath Test Suite series, part 6DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 6. In this session, we will cover Test Automation with generative AI and Open AI.
UiPath Test Automation with generative AI and Open AI webinar offers an in-depth exploration of leveraging cutting-edge technologies for test automation within the UiPath platform. Attendees will delve into the integration of generative AI, a test automation solution, with Open AI advanced natural language processing capabilities.
Throughout the session, participants will discover how this synergy empowers testers to automate repetitive tasks, enhance testing accuracy, and expedite the software testing life cycle. Topics covered include the seamless integration process, practical use cases, and the benefits of harnessing AI-driven automation for UiPath testing initiatives. By attending this webinar, testers, and automation professionals can gain valuable insights into harnessing the power of AI to optimize their test automation workflows within the UiPath ecosystem, ultimately driving efficiency and quality in software development processes.
What will you get from this session?
1. Insights into integrating generative AI.
2. Understanding how this integration enhances test automation within the UiPath platform
3. Practical demonstrations
4. Exploration of real-world use cases illustrating the benefits of AI-driven test automation for UiPath
Topics covered:
What is generative AI
Test Automation with generative AI and Open AI.
UiPath integration with generative AI
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
TrustArc Webinar - 2024 Global Privacy SurveyTrustArc
How does your privacy program stack up against your peers? What challenges are privacy teams tackling and prioritizing in 2024?
In the fifth annual Global Privacy Benchmarks Survey, we asked over 1,800 global privacy professionals and business executives to share their perspectives on the current state of privacy inside and outside of their organizations. This year’s report focused on emerging areas of importance for privacy and compliance professionals, including considerations and implications of Artificial Intelligence (AI) technologies, building brand trust, and different approaches for achieving higher privacy competence scores.
See how organizational priorities and strategic approaches to data security and privacy are evolving around the globe.
This webinar will review:
- The top 10 privacy insights from the fifth annual Global Privacy Benchmarks Survey
- The top challenges for privacy leaders, practitioners, and organizations in 2024
- Key themes to consider in developing and maintaining your privacy program
Why You Should Replace Windows 11 with Nitrux Linux 3.5.0 for enhanced perfor...SOFTTECHHUB
The choice of an operating system plays a pivotal role in shaping our computing experience. For decades, Microsoft's Windows has dominated the market, offering a familiar and widely adopted platform for personal and professional use. However, as technological advancements continue to push the boundaries of innovation, alternative operating systems have emerged, challenging the status quo and offering users a fresh perspective on computing.
One such alternative that has garnered significant attention and acclaim is Nitrux Linux 3.5.0, a sleek, powerful, and user-friendly Linux distribution that promises to redefine the way we interact with our devices. With its focus on performance, security, and customization, Nitrux Linux presents a compelling case for those seeking to break free from the constraints of proprietary software and embrace the freedom and flexibility of open-source computing.
2. Theor Appl Genet
genes which often confers a higher level of resistance than the procedures of McCallum and Seto-Goh (2003). Plants
would be expected from the level of resistance demon- were grown with 16 h supplemental lighting in a green-
strated by the genes in isolation (Samborski and Dyck house at approximately 20°C. Twelve days after inocula-
1982). The resistance genes Lr34 (German and Kolmer tion plants were classiWed as resistant (infection types; to
1992) and Lr13 (Kolmer 1992) were both demonstrated to 1), moderately resistant (infection types 1+ to 2) and sus-
enhance the level of resistance synergistically when in ceptible (infection types 3–4) as described by Stakman
combination with other Lr genes. Complex stacks of Lr et al. (1962). Parents of the F2 population were tested for
genes can be diYcult to construct using phenotypic selec- leaf rust resistance at the seedling and adult stage.
tion. For example the Canadian cultivar Pasqua carries Wve Thatcher NILs and cultivars carrying Lr22a were grown in
Lr genes including Lr11, Lr13, Lr14b, Lr30 and Lr34, but Weld plots at Glenlea, MB, Canada from 2003 to 2006 and
failed to retain Lr16 and Lr22a from the parental cross 2002 to 2006, respectively, to observe Lr gene eVectiveness.
(Dyck 1993a). With suitable markers a stack of seven Lr Plants were infected with natural leaf rust inoculum and rows
genes could have been stabilized in this cross. of susceptible wheat throughout the nurseries were artiWcially
Close molecular markers for all Lr genes can help in the inoculated with a mixture of virulence phenotypes found in
assembly and dissection of complex gene stacks in any western Canada during the previous year. Adult-plants were
cross. Lr22a has been physically mapped to chromosome rated for leaf rust based on a modiWed Cobb scale for incidence
2DS using telocentric mapping (Rowland and Kerber 1974). (Peterson et al. 1948) and severity was scored as R = resistant
In this paper we report both the genetic location and the (Xecks and small uredinia with necrosis), MR = moderately
identiWcation of a closely linked, unique molecular marker resistant (large necrotic Xecks and large uredinia), M = moder-
allele for Lr22a that was retained from Ae. tauschii. The ate (mixture of uredinia sizes), MS = moderately susceptible
application of this marker in diVerent genetic backgrounds (moderate to large uredinia with chlorosis), and S = susceptible
was examined on a broad range of wheat germplasm. (large uredinia without chlorosis or necrosis).
Molecular mapping
Materials and methods
DNA was extracted from lyophilized leaf tissue using a
Plant material and populations modiWed CTAB extraction (KleinhoVs et al. 1993). PCR
was performed with a cycle of 2 min 94°C, then 1 min
Lr22a was previously transferred to a synthetic hexaploid 95°C, 1 min 50–60°C, and 50 s 73°C for 30 cycles, fol-
RL5404 by crossing tetra-Canthatch (2n = 2x = 28, AABB) lowed by 5 min 73°C, using the following conditions: PCR
with Aegilops tauschii var. strangulata RL5271 (2n = 14, buVer 1£, dNTPs 0.2 mM each, MgCl2 1.5 mM, primers
DD; Dyck and Kerber 1970; Rowland and Kerber 1974). 10 pmol each, Taq DNA polymerase 1 U, and approxi-
This was followed by six backcrosses with Thatcher to pro- mately 50 ng genomic DNA. PCR products were separated
duce the line RL6044 (Thatcher*7//tetra-Canthatch/ on 5% denaturing polyacrylamide gels in TBE buVer
RL5271) which was then backcrossed with AC Domain to (89 mM tris, 89 mM boric acid, 20 mM EDTA) at 85 W for
produce the leaf rust resistant line 98B34-T4B (AC 2 h, and stained with silver (Promega, Madison, WI, USA).
Domain*6/RL6044) with Lr22a. RL5404 was also crossed Lr22a has been previously located on chromosome 2DS
with Neepawa (Neepawa*6/RL5404) to create the Lr22a- (Rowland and Kerber 1974). Microsatellite marker (SSR)
carrying near-isogenic line (NIL) RL4495. alleles located on chromosome 2DS were compared
An F2 population that segregated for Lr22a was created by between RL5271, RL5404, RL6044, Thatcher, 98B34-
crossing 98B34-T4B with the leaf rust susceptible line 98B26- T4B, and AC Domain. Polymorphic markers were tested
N1C01 (AC Domain*2/Sumai3//Grandin*2/AC Domain). for linkage to Lr22a using 68 of the susceptible individuals
Thatcher NILs carrying single Lr genes (Lr11, Lr13, Lr16, from the F2 population of 98B34-T4B £ 98B26-N1C01.
Lr22a and Lr34), cultivars carrying Lr22a (AC Minto) and Susceptible F2 plants were used for mapping because their
cultivars believed to carry Lr22a (5500HR and 5600HR) genotypes at the Lr22a locus were known. These suscepti-
were used in Weld tests to evaluate leaf rust resistance. ble individuals were selected for pustule uniformity to
avoid assigning homozygous susceptible genotypes at the
Disease rating Lr22 locus to heterozygous individuals that would falsely
appear to be recombinants. The location of linked SSR alle-
Segregation of Lr22a was followed in the 98B34- les was conWrmed using nulli/tetra and ditelocentric cytoge-
T4B £ 98B26-N1C01 F2 population by inoculating Xag netic stocks (Sears 1966; Sears and Sears 1978).
leaves with Puccinia triticina isolate TJBJ-77-2 (Long and SSR markers on chromosome 2DS were compared
Kolmer 1989; McCallum and Seto-Goh 2003) following between RL5271, RL5404, RL6044, Thatcher, 98B34-T4B,
123
3. Theor Appl Genet
AC Domain, RL4495, Neepawa, BW63, AC Minto, 5500HR, Aegilops tauschii donor of Lr22a (RL5271), the original
and 5600HR to determine which markers were co-introgres- synthetic (RL5404 = Tetra-Canthatch/RL5271) and two
sed with Lr22a from Ae. tauschii into Canadian wheat. backcross lines (RL6044 = Thatcher*7/RL5404 and
New SSR markers were added to the Agriculture and 98B34-T4B = AC Domain*6/RL6044). Microsatellite alle-
Agri-Food Canada Cereal Research Centre (AAFC-CRC) les from GWM296 and GWM455 were introgressed from
International Triticeae Mapping Initiative (ITMI) genetic RL5271 via RL5404 to these two resistant backcross lines
map (Opata85/Synthetic W-7984; Somers et al. unpub- (Table 1; Fig. 1). Thus GWM296 and GWM455 alleles
lished, ITMI-CRC). A newly developed Opata85/Synthetic from RL5271 have remained associated with Lr22a
doubled haploid (DH) population was tested to conWrm the through a minimum of 13 cycles of recombination in com-
marker order on 2DS found in the ITMI-CRC population. mon wheat.
The ITMI-CRC map was used to align the Lr22a linkage The same 14 SSR markers were used to assess the intro-
group with the genetic map of 2DS. Genetic distances were gression of Lr22a into RL4495 (Neepawa*6/RL5404) and
calculated using the Kosambi mapping function (Kosambi its derivatives which included BW63, AC Minto, 5500HR
1944). All maps were constructed using MapMaker version and 5600HR. RL4495 retained Ae. tauschii alleles from
3.0 (Lander et al. 1987). GWM455, GWM296, GWM261, WMC25, and WMC503,
To asses the potential of GMW296, the closest marker to and transmitted them to its derivatives (Table 1). Two other
Lr22a, as a selection tool in varying genetic backgrounds 118 introgression sizes were detected in RL4495, one with
diVerent cultivars and breeding lines were surveyed (Table 2). GWM455, GWM296, and GWM261, and one with
Alleles from these genotypes were compared to the allele GWM455 and GWM296. Since these introgressions are
ampliWed from RL5271, the Ae. tauschii donor of Lr22a. smaller than the one found in BW63 they cannot be in the
line of descent to AC Minto, 5500HR and 5600HR as these
cultivars have retained the largest introgression found in
Results RL4495.
In the F2 of 98B34-T4B £ 98B26-N1C01, 88 plants
Fourteen polymorphic microsatellite markers on chromo- were resistant, 216 plants had a moderately resistant infec-
some 2DS were evaluated in Thatcher, AC Domain, the tion type and 102 plants were susceptible. These numbers
Table 1 SSR alleles on chromosome 2DS introgressed along with Lr22a from Ae. tauschii into common wheat
Locusa Alleles on 2DSb
RL5271c RL5404c RL4495 c BW63c AC Minto RL6044c 98B34-T4Bc Neepawa Thatcher AC Domain
BARC124 T T A A A A A A A A
WMC111 T T A A A A A A A A
GWM210 T T A A A A A A A A
GWM455 T T T T T T T A A A
GWM296 T A A A
Lr22a T T T T T T T A A A
GWM261 T T T T T A A A A A
WMC025 T T T T T A A A A A
WMC503 T T T T T A A A A A
WMC112 T T A A A A A A A A
WMC470 T T A A A A A A A A
GWM484 T T A A A A A A A A
WMC453 T T A1 A1 A2 A1 A2 A1 A1 A2
GWM102 T T A2 A2 A1 A2 A2 A2 A2 A2
GWM515 T T A A A A A A A A
a
GWM markers are from Röder et al. (1998); WMC markers are from Somers et al. (2004); BARC markers are from Song et al. (2005)
b
T = Ae. tauschii allele; A = T. aestivum allele; subscript numbers diVerentiate between alleles within the same species
c
RL5271 = Ae. tauschii donor of Lr22a; RL5404 = synthetic hexaploid from tetra-Canthatch/RL5271; RL4495 = Neepawa*6/RL5404; BW63 is
derived from RL4495 and is the donor of Lr22a in all currently registered Canadian wheat cultivars; RL6044 = Thatcher*6/RL5404; 98B34-
T4B = AC Domain*6/RL6044. Two other introgressions were detected in RL4495 but are not shown because they lack the full introgression trans-
ferred to AC Minto via BW63
123
4. Theor Appl Genet
linked to the APR of Lr22a was on chromosome 2DS
(Fig. 1).
A minor conXict exists between our proposed order for
markers close to Lr22a and those published elsewhere
(Raupp et al. 2001). The marker order was clariWed by re-
genotyping lines recombinant in the region and adding
additional markers to the ITMI-CRC map. An alternate DH
population from the ITMI cross was also used to make a
comparative map. The DH map agreed with the ITMI-CRC
map (data not shown). Based on these results, we con-
cluded that the marker order on 2DS is as shown (Table 1;
Fig. 2) with the GWM296 locus 2.9 cM distal to Lr22a.
One hundred and Wve North American wheat cultivars
and breeding lines, four Asian lines, eight European culti-
vars and one South American wheat cultivar were surveyed
for alleles of GWM296 (Table 2). In total 14 alleles were
detected, with the most common being that found in
Thatcher (Fig. 1). Most Canadian hard-red spring wheat
cultivars are derived from Thatcher (B. McCallum and R.
DePauw unpublished). In this collection of wheat, the allele
from Ae. tauschii RL5271 was present in those lines and
cultivars that were expected to carry Lr22a and was absent
from all others (Table 2). BW63 was heterogeneous for
GWM296 with half the individuals tested carrying the
RL5271 allele. Two products were ampliWed from RL5271
that were 131 and 121 bp in size (Fig. 1). The size range of
all other chromosome 2DS alleles found were between 167
and 135 bp.
Cultivars expected to carry Lr22a, including AC Minto,
5500HR, and 5600HR, showed strong resistance to P. triti-
cina in the Weld from 2002 to 2006 (Table 3). Furthermore,
Fig. 1 Alleles of GWM296 found in RL5271 (Lr22a donor), RL6044 no isolates of P. triticina that are virulent to Lr22a have
(Thatcher*6/RL5271; carries Lr22a), Thatcher (recurrent wheat par- been found in Canadian virulence surveys between 2002
ent), Chinese Spring, nulli-2D/tetra-2B, nulli-2A/tetra-2B, ditelo 2DS,
and ditelo 2DL on a silver-stained polyacrylamide gel. The allele asso- and 2005 (McCallum and Seto-Goh 2005; McCallum and
ciated with Lr22a has DNA fragments that are 131 and 121 bp in size. Seto-Goh unpublished data; Table 4). The Thatcher NILs
A common chromosome 2DS allele in the North American wheat lines tested in the Weld showed that Lr22a provided good resis-
tested has the 167 and 135 bp fragments. The 176 bp fragment is from tance singly, while Lr34 showed moderate resistance, Lr16
the chromosome 2A locus
provided moderate to poor resistance, and Lr11 and Lr13
showed no improved resistance compared to Thatcher
Wt both a 3:1 ratio (resistant plus moderate resistant: sus- (Table 3).
ceptible; 23:1 = 0.02, P = 0.87), and a 1:2:1 ratio (resistant:
moderate resistant: susceptible; 21:2:1 = 2.64, P = 0.27). As
adult plants 98B34-T4B was resistant to P. triticina and Discussion
98B26-N1C01 was susceptible, while as seedlings both
lines were susceptible. This conWrms that the F2 population Wheat SSR maps reveal that coverage by polymorphic
segregated for the APR conferred by Lr22a. The Ae. tau- markers is non-uniform (Somers et al. 2004). Of the three
schii alleles of GWM296 and GWM455 (both present in genomes of common wheat, the D genome was added most
98B34-T4B) were both polymorphic with respect to recently and has the shortest evolutionary life span at the
98B26-N1C01. Based on 68 susceptible F2 plants repre- hexaploid level. Therefore, the degree of polymorphism is
senting 136 gametes, GWM296 was 2.9 cM and GWM455 lowest for the D genome chromosomes. By contrast, Ae.
was 4.4 cM from the Lr22a locus (Fig. 2). Testing with tauschii is an older, polymorphic, broadly distributed dip-
nulli-2D/tetra-2B, nulli-2A/tetra-2B, ditelo 2DS, and ditelo loid that has contributed the D genome to many polyploids
2DL conWrmed that the locus of GWM296 shown to be in the Triticeae. These diVerences in polymorphism were
123
5. Theor Appl Genet
Fig. 2 Alignment of the Lr22a
and ITMI-CRC maps with two
previously published maps of
chromosome 2DS. The map of
98B34-T4B/98B26-N1C01 was
based on 68 F2 plants while the
ITMI-CRC map was derived
from 68 recombinant inbred
lines from the cross of Opata85/
W-7984 (W-7984 = Ae. tauscii/
Altar84 durum; this cross is
commonly called Opata/Syn-
thetic). The map of Raupp et al.
(2001) reports the mapping of
Lr39, however, Singh et al.
(2004) found that Lr39 = Lr41
evident in this study as all 14 SSR markers tested on chro- the GWM296 locus (Schnurbusch et al. 2004). Schnur-
mosome 2DS were polymorphic between the Ae. tauschii busch et al. (2004) speculated that this QTL on 2DS could
accession RL5271 and the two recurrent parents, Thatcher represent Lr22 and our data supports this hypothesis.
and AC Domain. Thatcher and AC Domain were mono- GWM455 was previously reported to be polymorphic
morphic for 13 of the 14 SSR markers (Table 1). between Thatcher and RL6044 in an eVort to exclude Lr22a
In this study SSR markers previously mapped to 2DS as an allele of other Lr genes introgressed from Ae. tau-
were compared between backcross lines and the recurrent schii, but linkage experiments between Lr22a and
parents in order to identify candidate markers that might be GWM455 were not performed (Raupp et al. 2001).
linked to Lr22a. Out of the 14 loci investigated, two poly- Other genes of interest are found near the Lr22 locus on
morphic markers were transferred through thirteen rounds chromosome 2DS. Lr41 (Lr41 = Lr39; Singh et al. 2004) is
of backcrossing and both were then shown to be closely distal to GWM210 (Raupp et al. 2001) whereas Lr22a is
linked to the target gene. This screening strategy was suc- proximal. The order of loci near Lr22 is inconsistent
cessful because of the high marker density and high degree between our map (ITMI-CRC) and the map of Raupp et al.
of polymorphism between chromosome 2DS of Ae. tauschii (2001). After re-genotyping lines recombinant on 2DS, the
and the corresponding chromosome of common wheat. marker order as presented in the ITMI-CRC map is the most
Based on recombination in the F2 population, the mini- likely (Fig. 2). However, the marker orders in the ITMI-
mum size of the segment introgressed into RL6044 and CRC map and the map presented by Raupp et al. (2001)
98B34-T4B was 4.4 cM and the probable size was 9 cM both place Lr22a and Lr41 on opposite sides of GWM210
(assuming the crossovers occurred at the midpoint of the (Fig. 2). Both introgressions of Lr22a into wheat, RL6044
Xanking intervals; Fig. 2). In contrast, the Lr22a introgres- and RL4495, retained SSR markers proximal to GWM210.
sion from RL5271, via RL5405, into RL4495 included up Furthermore, Lr41 is a seedling resistance gene and Lr22a is
to Wve SSR markers. The largest introgression represents a an adult plant resistance gene. McIntosh et al. (1995)
minimum of 17 cM and a probable size of 20 cM as esti- recorded no instances of an adult-plant resistance gene with
mated from the ITMI-CRC map (Table 1; Fig. 2). This an allele that confers seedling resistance for any of the three
larger introgression has persisted from RL4495 into three rusts of wheat. In the particular case of Lr22 there are two
Canadian cultivars, AC Minto, 5500HR, and 5600HR. alleles that have been reported and both provide adult-plant
Three-point linkage values observed in the F2 population resistance (Rowland and Kerber 1974; Dyck 1979). This
(98B34-T4B/98B26-N1C01) conWrmed that Lr22a, data agrees with the conclusion of Raupp et al. (2001) that
GWM296 and GWM455 are closely linked (Fig. 2). In a Lr41 is not allelic to Lr22a. The dwarWng gene Rht8 is
study of durable leaf rust resistance in Swiss winter wheat, closely linked with GWM261 (Korzun et al. 1998) and is
QTL analysis revealed a signiWcant narrow QTL close to proximal to the Lr22 locus (Fig. 2).
123
6. Theor Appl Genet
Table 2 Cultivars from diVerent geographical origins screened with (Table 2). The uniqueness of the GWM296 allele, ease of
GWM296, the closest marker to Lr22a, to survey allele diversity and scoring, and its close association with Lr22a provides a
cross-applicability means to include Lr22a in complex gene stacks and to clas-
Ae. tauschii Other allelesa sify existing lines for the distribution of Lr22a provision-
allele ally.
North America North America CDC Teal Superb
In the survey of wheat breeding lines and cultivars
5500HR 5601HR Columbus Thatcher
GWM296 was useful in tracking the transmission of Lr22a
through the genealogy of Canadian wheat. BW63 is an
5600HR AC Barrie Grandin South America
important source of leaf rust resistance in the pedigree of
AC Minto AC Bellatrix Invader Frontana
b several Canadian bread wheat varieties containing Lr11,
BW63 AC Cadillac Kanata Asia
Lr14b, Lr22a, Lr30 and Lr34 (Dyck 1993a). The data indi-
AC Cora Katepwa Chinese Spring
cated that BW63 was heterogeneous for the presence of
AC Domain Lancer Nyu Bai
Lr22a and this could explain why AC Minto (Columbus/
AC Elsa Laura Wuhan-1
BW63//Katepwa/BW552; Townley-Smith et al. 1993)
AC Intrepid McClintock Sumai-3
inherited Lr22a from BW63 while Pasqua (BW63*2/
AC Majestic McKenzie Europe
Columbus) did not (Dyck 1993a). Since BW63 would have
AC Readymade Neepawa Alcedo
demonstrated a high degree of adult-plant resistance it
AC Splendor Norstar Alidos
would have been diYcult to track the incorporation Lr22a
AC Tempest Park Altos during the development of Pasqua. All of the Canadian
Alikat Pasqua Bezostaya cultivars (Table 2) and breeding lines tested that inherited
Alsen Prodigy Kontrast the RL5271 allele of GWM296, and presumably Lr22a,
CDC Falcon Roblin Milan 13 were derived from AC Minto except for 98B34-T4B
CDC Kestrel Snowbird Welford (AC Domain*6/3/Thatcher*7//tetra-Canthatch/Ae. tauschii
CDC Osprey Somerset Zentos RL5271).
Only named cultivars are listed. An additional 65 North American In Canada Lr22a is deployed in AC Minto (registered in
breeding lines were tested. Six of these breeding lines carried the Ae. 1991) and putatively in 5500HR (2000) and 5600HR
tauschii allele. Five of these had AC Minto as a parent while the sixth (1999). There are no reports of US cultivars that carry
line was 98B34-T4B (see “Materials and methods”)
a
Lr22a (JA Kolmer, personal communication). The Cana-
Thirteen alleles of GWM296 were found in addition to the allele int-
rogressed from Ae. tauschii
dian cultivars that carry Lr22a have only occupied small
b
BW63 was not a released cultivar, however, it was an important Lr
percentages (0.13–0.95%) of the wheat production area in
gene source in Canadian wheat breeding programs. The allele scores Canada from 1998 to 2006 (Canadian Wheat Board, http://
for BW63 indicate it was heterogeneous for the GWM296 marker and www.cwb.ca). Thus Lr22a has had relatively low exposure
presumably for Lr22a to P. triticina in Canada and the US. The detection of an
ineVective race-speciWc “b” allele of Lr22 (Dyck 1979)
Even though the D genome of wheat has reduced poly- implies that Lr22a will also prove to be race speciWc. The
morphism, 14 alleles for GWM296 were identiWed on 2DS. absence of virulence on Lr22a could be explained in part by
Although both of the 2DS alleles illustrated in Fig. 1 have its lack of exposure to P. triticina.
two fragments, other genotypes tested exhibited a single AC Minto carries Lr11, Lr13 and Lr22a (Kolmer 1997).
fragment. For example, the 2DS allele of GWM296 found Presense of Lr22a in AC Minto is conWrmed by presense of
in AC Splendor has a single fragment of 167 bp while the Wve Ae. tauschii alleles found in BW63 (Table 1). Each
Superb has fragments of 149 and 137 bp (not shown). Thus year AC Minto showed Weld resistance that was better than
heterozygotes may have two, three or four fragments from the Lr22a NIL, indicating that Lr13 and/or Lr11 had the
chromosome 2DS while homozygotes may have one or ability to interact synergistically with Lr22a even though
two. Therefore caution is required when classifying an indi- they were ineVective independently (Table 3). Lr13 is
vidual’s genotype without prior knowledge of parental known to interact synergistically with some other Lr genes
haplotypes and the degree of homozygosity. It should be (Kolmer 1992), however, no data has been reported on the
noted that GWM296 also ampliWed a locus on chromosome potential interaction between Lr13 and Lr22a. Cultivars
2A; however, this larger fragment (176 § 4 bp) did not 5600HR (AC Minto//Columbus/Roblin) and 5500HR (AC
overlap with the 2DS fragments in any of the genotypes Minto/3/MN72506/Columbus//RL4473) both received the
tested. Despite the allele diversity of GWM296 on chromo- Ae. tauschii alleles found in BW63, and presumably Lr22a,
some 2D, the allele that was co-introgressed with Lr22a via AC Minto (Table 1). In addition to Lr22a, 5600HR and
from Ae. tauschii was not found in any common wheat 5500HR may also carry Lr11, Lr13, and Lr16, and Lr11
lines tested except for those believed to carry Lr22a and Lr16, respectively, based on pedigree and their
123
7. Theor Appl Genet
Table 3 Virulence of P. triticina on Lr22a and to selected cultivars and NILs in Canada
Year No. of Virulence Field reaction to P. triticinae
isolatesa on Lr22a
AC Mintob 5600 HRc 5500 HRc Tcd Tc-Lr11d Tc-Lr13d Tc-Lr16d Tc-Lr22ad Tc-Lr34d
2002 71 0 TR R TR R 10 RMR 80 S – – – – –
2003 29 0 TR R 0R 0R 80 S 70 S 80 S 65 M 7 RMR 25 M
2004 58 0 3 MR 0R 15 MR 80 S 80 S 80 S 60 M 19 MR 20 M
2005 81 0 15 RMR 5 RMR 5 RMR 80 S 80 S 80 S 70 MSS 20 M 40 M
2006 – – 0R 0R 0R 80 S 80 S 80 S 50 M 10 RMR 40 M
a
Survey of Canadian P. triticina isolates for 2002 is from McCallum and Seto-Goh (2005) and (2003) to (2005) is from McCallum and Seto-Goh
(unpublished data)
b
AC Minto is reported to have Lr11, Lr13 and Lr22a (Kolmer 1992)
c
5600 HR and 5500 HR are derivatives of AC Minto that carry the SSR allele linked to Lr22a. Our evidence suggests that these cultivars carry
Lr11, Lr16 and Lr22a. It is also possible that these two carry Lr34
d
Tc = Thatcher, Tc-Lr11 = RL6053, Tc-Lr13 = RL4031, Tc-Lr16 = RL6005, Tc-Lr22a = RL6044, Tc-Lr34 = RL6058
e
Field ratings are based on a modiWed Cobb scale for incidence (Peterson et al. 1948) and severity was scored as R resistant (Xecks and small
uredinia with necrosis), MR moderately resistant (large necrotic Xecks and large uredinia), M moderate (mixture of uredinia sizes), MS moderately
susceptible (moderate to large uredinia with chlorosis), and S susceptible (large uredinia without chlorosis or necrosis)
reactions to diVerent P. triticina virulence phenotypes Post-Graduate Scholarship. Additional Wnancial support was received
(Samborski and Dyck 1982; Dyck 1993b; B. McCallum from the Agriculture and Agri-Food Canada Matching Investment Ini-
tiative and the Western Grains Research Foundation Check-oV. Inocu-
unpublished). In the Weld all three Canadian cultivars that lum was provided by Pat Seto-Goh. Figure formatting assistance was
carry Lr22a showed leaf rust resistance that is better than provided by Mike Shillinglaw.
the individual genetic components of their resistance
(Table 3). Although Lr22a appeared to be the key compo-
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