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The John Innes Centre is a major centre for research into the genetics, cytogenetics, molecular biology, pathology and biotechnology of cereals. Most work focuses on wheat, but barley, rye, maize, rice and millet species are also studied. Work on cereal cytogenetics is concerned with studying chromosome pairing and transferring new variation, particularly for biotic and abiotic stress resistance, from related alien species into wheat. The transfer of genes for mildew resistance, aluminum tolerance and salt tolerance are recent successes. Particularly significant at the present time is work to clone the gene Ph1 ,responsible for controlling the diploid meiotic behavior of hexaploid wheat. Using a comparative mapping approach and rice molecular tools, possible rice homologues of Ph1 have been isolated on rice BACs, and sequencing of these BACs has identified candidate genes. Work on cereal genomics is concerned with developing new molecular markers, particularly SSR markers, and using these for mapping and fingerprinting European wheat germplasm. Work to develop Single Nucleotide Polymorphism (SNP) systems has been initiated. Additionally, new genomic tools are being developed such as a hexaploid wheat BAC library, and the Department is involved in the ITEC EST sequencing and databasing, and the development of wheat DNA microarray technology. The Department has large projects concerned with identifying new major genes and QTL controlling important agronomic traits using molecular marker mediated forms of genetic analysis and precise genetic stocks, particularly recombinant substitution lines and recombinant doubled haploid populations. Major targets are genes controlling adaptation, drought and salt tolerance, pre harvest sprouting tolerance, bread making and animal feed quality, and adult plant resistance to fungal pathogens. The Department is a major centre for cereal transformation with programs on the genetic engineering of wheat, barley and rice, mainly, at present, using biolistics.A non destructive marker system using the luciferase gene is used routinely, mediated by special JIC developed transformation cassettes. A major component of this work is technology development, where systems for Agrobacterium mediated transformation are being developed so that marker free, clean gene technology can be used. In rice, the major target traits being engineered are for pest and disease resistance into West African varieties, particularly the use of protease inhibitor constructs effective against nematodes, and a homology dependant induced resistance mechanism against rice yellow mottle virus. In barley, quality traits are being modified, such as the introduction of a fungal enzyme to increase starch conversion during the malting process, and a gene for lysine biosynthesis to improve nutritional value. Alongside technology development, molecular analysis of transgene structure, expression, and the physical and genetic mapping of transgenes is being carried out. Work on cereal fungal pathology is concerned with studying pathogen variation and molecular biology, and discovering new host resistance genes against isolates of the major UK fungal pathogens; yellow and brown rust, powdery mildew, Septoria triticii , eyespot and Fusarium species. A mixture of conventional pathology and molecular pathology approaches are used in this work, and a major target is the cloning of avirulence genes in the pathogen and resistance genes in the host, and understanding the mechanisms of virulence and resistance. New genes for resistance to Septoria species on chromosome 7D have recently been mapped. For resistance breeding against Fusarium species, new molecular diagnostic tools have been developed to quantify infection levels using quantitative PCR, so that the effects of specific species on infection levels in the stem base and in the head can be characterized. Details of the work can be viewed at the web site : www.jic.bbsrc.ac.uk.
The John Innes Center is a major center for research into the genetics, cytogenetics, molecular biology, pathology and biotechnology of cereals. Most work focuses on wheat, but barley, rye, maize, rice and millet species are also studied. Work on cereal cytogenetics is concerned with studying chromosome pairing and transferring new variation, particularly for biotic and abiotic stress resistance, from related alien species into wheat. The transfer of genes for mildew resistance, aluminum tolerance and salt tolerance are recent successes. Particularly significant at the present time is is work to clone the gene Ph1, responsible for controlling the diploid meiotic behavior of hexaploid wheat. Using a comparative mapping approach and rice molecular tools, possible rice homologues of Ph1 have been isolated on rice BACs, and sequencing of these BACs with identified candidate genes. Work on cereal genomics is concerned with developing new molecular markers, particularly SSR markers, a nd using these for mapping and fingerprinting European wheat germplasm. Work to develop Single Nucleotide Polymorphism (SNP) systems has been initiated. Additionally, new genomic tools are being developed such as a hexaploid wheat BAC library, and the Department is involved in the ITEC EST sequencing and databasing, and the development of wheat DNA microarray technology. The Department has large projects concerned with identifying new major genes and QTL controlling important agronomic traits using molecular marker mediated forms of genetic analysis and precise genetic stocks, particularly recombinant substitution lines and recombinant doubled haploid populations. Major targets are genes controlling adaptation, drought and salt tolerance, pre harvest sprouting tolerance, bread making and animal feed quality, and adult plant resistance to fungal pathogens. The Department is a major center for cereal transformation with programs on the genetic engineering of wheat, barley and rice,mainly, at present, using biolistics. A non destructive marker system using the luciferase gene is used routinely, mediated by special JIC developed transformation cassettes. A major component of this work is technology development, where systems for Agrobacterium mediated transformation are being developed so that that marker free, clean gene technology can be used. In rice, the major target traits being engineered are for pest and disease resistance into West African varieties, particularly the use of protease inhibitor constructs against against nematodes, and a homology dependant induced resistance mechanism against rice yellow mottle virus. In barley, quality traits are being modified, such as the introduction of a fungal enzyme to increase starch conversion during the malting process, and a gene for lysine biosynthesis to improve nutritional value. Alongside technology development, molecular analysis of transgene structure , expression, and the physical and genetic mapping of transgenes is being carried out. Work on cereal fungal pathology is concerned with studying pathogen variation and molecular biology, and discovering new host resistance genes against isolates of the major UK fungal pathogens; yellow and brown rust, powdery mildew, Septoria triticii, eyespot and Fusarium species. A mixture of conventional pathology and molecular pathology approaches are used in this work, and a major target is the cloning of avirulence genes in the pathogen and resistance genes in the host, and understanding the mechanisms of virulence and resistance. New genes for resistance to Septoria species on chromosome 7D have recently been mapped. For resistance breeding against Fusarium species, new molecular diagnostic tools have been developed to quantify infection levels using quantitative PCR, so that the effects of specific species on infection levels in the stem base and in the head can be characterized. Details of the work can be viewed at the web site: www.jic.bbsrc.ac.uk.