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The complex orbifold structure of the moduli space of Riemann surfaces of genus g (g≥2) produces a stratification into complex subvarieties named equisymmetric strata. Each equisymmetric stratum is formed by the surfaces where the group of automorphisms acts in a topologically equivalent way. The Riemann surfaces in the equisymmetric strata of dimension one are of two structurally different types. Type 1 equisymmetric strata correspond to Riemann surfaces where the group of automorphisms produces a quotient surface of genus zero, while those of Type 2 appear when such a quotient is a surface of genus one. Type 1 equisymmetric strata have been extensively studied by the authors of the present work in a previous recent paper, we now focus on Type 2 strata. We first establish the existence of such strata and their frequency of occurrence in moduli spaces. As a main result we obtain a complete description of Type 2 strata as coverings of the sphere branched over three points (Belyi curves) and where certain isolated points (punctures) have to be eliminated. Finally, we study in detail the doubly infinite family of Type 2 strata whose automorphism groups have order the product of two primes.

The complex orbifold structure of the moduli space of Riemann surfaces of genus g (g≥2) produces a stratification into complex subvarieties named equisymmetric strata. Each equisymmetric stratum is formed by the surfaces where the group of automorphisms acts in a topologically equivalent way. The Riemann surfaces in the equisymmetric strata of dimension one are of two structurally different types. Type 1 equisymmetric strata correspond to Riemann surfaces where the group of automorphisms produces a quotient surface of genus zero, while those of Type 2 appear when such a quotient is a surface of genus one. Type 1 equisymmetric strata have been extensively studied by the authors of the present work in a previous recent paper, we now focus on Type 2 strata. We first establish the existence of such strata and their frequency of occurrence in moduli spaces. As a main result we obtain a complete description of Type 2 strata as coverings of the sphere branched over three points (Belyi curves) and where certain isolated points (punctures) have to be eliminated. Finally, we study in detail the doubly infinite family of Type 2 strata whose automorphism groups have order the product of two primes.

The complex orbifold structure of the moduli space of Riemann surfaces of genus g (g≥2) produces a stratification into complex subvarieties named equisymmetric strata. Each equisymmetric stratum is formed by the surfaces where the group of automorphisms acts in a topologically equivalent way. The Riemann surfaces in the equisymmetric strata of dimension one are of two structurally different types. Type 1 equisymmetric strata correspond to Riemann surfaces where the group of automorphisms produces a quotient surface of genus zero, while those of Type 2 appear when such a quotient is a surface of genus one. Type 1 equisymmetric strata have been extensively studied by the authors of the present work in a previous recent paper, we now focus on Type 2 strata. We first establish the existence of such strata and their frequency of occurrence in moduli spaces. As a main result we obtain a complete description of Type 2 strata as coverings of the sphere branched over three points (Belyi curves) and where certain isolated points (punctures) have to be eliminated. Finally, we study in detail the doubly infinite family of Type 2 strata whose automorphism groups have order the product of two primes.

Scald caused by Rhynchosporium commune is one of the most destructive barley diseases worldwide. Accumulation of adult plant resistance (APR) governed by multiple resistance alleles is predicted to be effective and long-lasting against a broad spectrum of pathotypes. However, the molecular mechanisms that control APR remain poorly understood. Here, quantitative trait loci (QTL) analysis of APR and fine mapping were performed on five barley populations derived from a common parent Vlamingh, which expresses APR to scald. Two QTLs, designated QSc.VR4 and QSc.BR7, were detected from a cross between Vlamingh and Buloke. Our data confirmed that QSc.VR4 is an effective and stable APR locus, residing on the short arm of chromosome 4H, and QSc.BR7 derived from Buloke may be an allele of reported Rrs2. High-resolution fine mapping revealed that QSc.VR4 is located in a 0.38 Mb genomic region between InDel markers 4H2282169 and 4H2665106. The gene annotation analysis and sequence comparison suggested that a gene cluster containing two adjacent multigene families encoding leucine-rich repeat receptor kinase-like proteins (LRR-RLKs) and germin-like proteins (GLPs), respectively, is likely contributing to scald resistance. Adult plant resistance (APR) governed by QSc.VR4 may confer partial levels of resistance to the fungus Rhynchosporium commune and, furthermore, be an important resource for gene pyramiding that may contribute broad-based and more durable resistance.

Recalcitrance to tissue culture and genetic transformation is the major bottleneck for gene manipulation in crops. In barley, immature embryos of Golden Promise have been mainly used as explants for transformation. However, the genotype-dependent approach limits the genetic modification in commercial varieties. Here, we develop an anther culture-based system that effectively creates transgenic and gene-edited plants from commercial barley varieties. The protocol was tested in four Australian varieties and Golden Promise with different phenology, callus induction and green plant regeneration responses. Agrobacterium-mediated transformation was performed on microspore-derived callus when targeting the HvPDS gene, and T0 albinos with targeted mutations were successfully obtained from commercial varieties. Further editing of three targets was achieved with an average mutation rate of 53% in the five varieties. In the 51 analysed T0 individuals, Cas9 induced about 69% of single-base insertion/deletions and two-base deletions in targeting sites, with variable mutation rates among targets and varieties. Both on-target and off-target activities were detected in T1 progenies. Compared with immature embryo protocols, this genotype-independent platform can deliver a high editing efficiency and more regenerants within a similar time frame. It is promising for functional genomics and application of CRISPR technologies for precise improvement in commercial varieties.

Recalcitrance to tissue culture and genetic transformation is the major bottleneck for gene manipulation in crops. In barley, immature embryos of Golden Promise have been mainly used as explants for transformation. However, the genotype-dependent approach limits the genetic modification in commercial varieties. Here, we develop an anther culture-based system that effectively creates transgenic and gene-edited plants from commercial barley varieties. The protocol was tested in four Australian varieties and Golden Promise with different phenology, callus induction and green plant regeneration responses. Agrobacterium-mediated transformation was performed on microspore-derived callus when targeting the HvPDS gene, and T0 albinos with targeted mutations were successfully obtained from commercial varieties. Further editing of three targets was achieved with an average mutation rate of 53% in the five varieties. In the 51 analysed T0 individuals, Cas9 induced about 69% of single-base insertion/deletions and two-base deletions in targeting sites, with variable mutation rates among targets and varieties. Both on-target and off-target activities were detected in T1 progenies. Compared with immature embryo protocols, this genotype-independent platform can deliver a high editing efficiency and more regenerants within a similar time frame. It is promising for functional genomics and application of CRISPR technologies for precise improvement in commercial varieties.

Scald caused by Rhynchosporium commune is one of the most destructive barley diseases worldwide. Accumulation of adult plant resistance (APR) governed by multiple resistance alleles is predicted to be effective and long-lasting against a broad spectrum of pathotypes. However, the molecular mechanisms that control APR remain poorly understood. Here, quantitative trait loci (QTL) analysis of APR and fine mapping were performed on five barley populations derived from a common parent Vlamingh, which expresses APR to scald. Two QTLs, designated QSc.VR4 and QSc.BR7, were detected from a cross between Vlamingh and Buloke. Our data confirmed that QSc.VR4 is an effective and stable APR locus, residing on the short arm of chromosome 4H, and QSc.BR7 derived from Buloke may be an allele of reported Rrs2. High-resolution fine mapping revealed that QSc.VR4 is located in a 0.38 Mb genomic region between InDel markers 4H2282169 and 4H2665106. The gene annotation analysis and sequence comparison suggested that a gene cluster containing two adjacent multigene families encoding leucine-rich repeat receptor kinase-like proteins (LRR-RLKs) and germin-like proteins (GLPs), respectively, is likely contributing to scald resistance. Adult plant resistance (APR) governed by QSc.VR4 may confer partial levels of resistance to the fungus Rhynchosporium commune and, furthermore, be an important resource for gene pyramiding that may contribute broad-based and more durable resistance.

Tillering or branching is an important agronomic trait in plants, especially cereal crops. Previously, in barley (Hordeum vulgare) ‘Vlamingh’, we identified the high number of tillers1 (hnt1) mutant from a γ-ray-treated segregating population. hnt1 exhibited more tillers per plant, narrower leaves, and reduced plant height compared with the wild-type parent. In this study, we show that the hnt1-increased tiller number per plant is caused by accelerated outgrowth of tiller buds and that hnt1 narrower leaves are caused by a reduction in vascular tissue and cell number. Genetic analysis revealed that a 2-bp deletion in the gene HORVU2Hr1G098820 (HvHNT1), encoding a trypsin family protein, was responsible for the hnt1 mutant phenotype. Gene function was further confirmed by transgenic complementation with HvHNT1 and RNA interference experiments. HvHNT1 was expressed in vascular tissue, leaf axils, and adventitious root primordia and shown to negatively regulate tiller development. Mutation of HvHNT1 led to the accumulation of a putative cyclophilin-type peptidyl-prolyl cis/trans-isomerase (HvPPIase), which physically interacts with the HvHNT1 protein in the nucleus of plant cells. Our data suggest that HvHNT1 controls tiller development and leaf width through HvPPIase, thus contributing to understanding of the molecular players that control tillering in barley…

Strategies to breed sterile leucaena for Western Australia include plant breeding and biotechnology tools to generate sterile lines at both the tetraploid and triploid ploidy levels. For tetraploids, the main target species is the commercial Leucaena leucocephala, that is well known for its potential as a high-quality, productive and persistent forage. Gene editing technologies (CRISPR) will be utilized to edit out flowering genes and develop a non-flowering L. leucocephala. For triploids, the strategy is to cross tetraploid species (L. leucocephala and/or L. diversifolia) with diploid species to generate sterile triploid hybrids. The diploid parents will include species that have good forage attributes such as L. collinsii, L. macrophylla, L. shannonii and L. pulverulenta. Several of these triploid crosses have already been created by the Department of Primary Industries and Regional Development (Perth, Western Australia) and will be evaluated in the Kimberley and Pilbara regions of Western Australia for their agronomic performance and sterility. Vegetative propagation will be required for the tetraploid gene-edited non-flowering L. leucocephala. Triploids can either be vegetatively propagated, once generated, or generated via a seed production nursery.

Barley occupies the widest ecological area among the major cereal crops, thereby generating a high potential for adaptive genetic diversity against various environmental factors. Colored barley such as black grain barley has been suggested to result from environmental adaptation to biotic and abiotic stresses. Using one double haploid population (433 lines), plus three F5 recombinant inbred line (RIL) populations (1,009 lines), the black lemma and pericarp (Blp) gene was mapped between two Insertion/deletion (Indel) markers MC_1570156 and MC_162350 with a physical distance of 0.807 Mb, containing 21 annotated genes in the mapped interval. Whole-genome re-sequencing was performed on two Tibetan wild barley lines (X1 and W1) with black grain phenotype. The probable candidate genes for Blp were discussed based on gene functional annotation and gene sequence variation analyses. Thirteen polymorphic Indel markers covering the target genetic region were used to analyze 178 barley accessions including 49 black husk entries. Genotype-based clustering analyses showed that the black landraces of different geographical background may have evolved from a single origin. Our study represents a significant improvement on the genetic mapping of Blp and would facilitate future study on the characterization of the genetic basis underlying this interesting agronomic trait.

Strategies to breed sterile leucaena for Western Australia include plant breeding and biotechnology tools to generate sterile lines at both the tetraploid and triploid ploidy levels. For tetraploids, the main target species is the commercial Leucaena leucocephala, that is well known for its potential as a high-quality, productive and persistent forage. Gene editing technologies (CRISPR) will be utilized to edit out flowering genes and develop a non-flowering L. leucocephala. For triploids, the strategy is to cross tetraploid species (L. leucocephala and/or L. diversifolia) with diploid species to generate sterile triploid hybrids. The diploid parents will include species that have good forage attributes such as L. collinsii, L. macrophylla, L. shannonii and L. pulverulenta. Several of these triploid crosses have already been created by the Department of Primary Industries and Regional Development (Perth, Western Australia) and will be evaluated in the Kimberley and Pilbara regions of Western Australia for their agronomic performance and sterility. Vegetative propagation will be required for the tetraploid gene-edited non-flowering L. leucocephala. Triploids can either be vegetatively propagated, once generated, or generated via a seed production nursery.

Barley occupies the widest ecological area among the major cereal crops, thereby generating a high potential for adaptive genetic diversity against various environmental factors. Colored barley such as black grain barley has been suggested to result from environmental adaptation to biotic and abiotic stresses. Using one double haploid population (433 lines), plus three F5 recombinant inbred line (RIL) populations (1,009 lines), the black lemma and pericarp (Blp) gene was mapped between two Insertion/deletion (Indel) markers MC_1570156 and MC_162350 with a physical distance of 0.807 Mb, containing 21 annotated genes in the mapped interval. Whole-genome re-sequencing was performed on two Tibetan wild barley lines (X1 and W1) with black grain phenotype. The probable candidate genes for Blp were discussed based on gene functional annotation and gene sequence variation analyses. Thirteen polymorphic Indel markers covering the target genetic region were used to analyze 178 barley accessions including 49 black husk entries. Genotype-based clustering analyses showed that the black landraces of different geographical background may have evolved from a single origin. Our study represents a significant improvement on the genetic mapping of Blp and would facilitate future study on the characterization of the genetic basis underlying this interesting agronomic trait.

Tiller angle, an important agronomic trait, contributes to crop production and plays a vital role in breeding for plant architecture. A barley line V-V-HD, which has prostrate tillers during vegetative growth and erect tillers after booting, is considered the ideal type for repressing weed growth and increasing leaf area during early growth. Genetic analysis identified that the prostrate trait in V-V-HD is controlled by a single gene. A double haploid population with 208 lines from V-V-HD × Buloke was used to map the prostrate growth gene. Ninety-six SNP markers were used for primary mapping, and subsequently, SSR and InDel markers were used for fine mapping. The gene was fine-mapped to a 3.53 Mb region on chromosome 3HL between the markers InDelz3028 and InDelz3032 with 52 candidate genes located in this region. Gene annotation analysis of the 52 genes within the target region indicated that a gene involved in zinc-ion binding (gene ID HORVU3Hr1G090910) is likely to be the candidate gene for prostrate growth in V-V-HD, and is linked to the denso/sdw gene. Association analysis showed that prostrate plants were shorter, flowered later.

Tiller angle, an important agronomic trait, contributes to crop production and plays a vital role in breeding for plant architecture. A barley line V-V-HD, which has prostrate tillers during vegetative growth and erect tillers after booting, is considered the ideal type for repressing weed growth and increasing leaf area during early growth. Genetic analysis identified that the prostrate trait in V-V-HD is controlled by a single gene. A double haploid population with 208 lines from V-V-HD × Buloke was used to map the prostrate growth gene. Ninety-six SNP markers were used for primary mapping, and subsequently, SSR and InDel markers were used for fine mapping. The gene was fine-mapped to a 3.53 Mb region on chromosome 3HL between the markers InDelz3028 and InDelz3032 with 52 candidate genes located in this region. Gene annotation analysis of the 52 genes within the target region indicated that a gene involved in zinc-ion binding (gene ID HORVU3Hr1G090910) is likely to be the candidate gene for prostrate growth in V-V-HD, and is linked to the denso/sdw gene. Association analysis showed that prostrate plants were shorter, flowered later.

Leaf color is an important trait for not only controlling crop yield but also monitoring plant status under temperature stress. In this study, a thermo-inducible chlorophyll-deficient mutant, named V-V-Y, was identified from a gamma-radiated population of the barley variety Vlamingh. The leaves of the mutant were green under normal growing temperature but turned yellowish under high temperature in the glasshouse experiment. The ratio of chlorophyll a and chlorophyll b in the mutant declined much faster in the first 7–9 days under heat treatment. The leaves of V-V-Y turned yellowish but took longer to senesce under heat stress in the field experiment. Genetic analysis indicated that a single nuclear gene controlled the mutant trait. The mutant gene (vvy) was mapped to the long arm of chromosome 4H between SNP markers 1_0269 and 1_1531 with a genetic distance of 2.2 cM and a physical interval of 9.85 Mb. A QTL for grain yield was mapped to the same interval and explained 10.4% of the yield variation with a LOD score of 4. This QTL is coincident with the vvy gene interval that is responsible for the thermo-inducible chlorophyll-deficient trait. Fine mapping, based on the barley reference genome sequence, further narrowed the vvy gene to a physical interval of 0.428 Mb with 11 annotated genes. This is the first report of fine mapping a thermo-inducible chlorophyll-deficient gene in barley.

A doubled haploid (DH) population of barley (Hordeum vulgare L.) generated from salinity tolerant genotype CM72 and salinity sensitive variety Gairdner was studied for salinity stress tolerance at germination, seedling emergence and first leaf full expansion growth stages. Germination study was conducted with deionized water, 150 mM and 300 mM NaCl treatments. Seedling stage salinity tolerance was conducted with three treatments: control, 150 mM NaCl added at seedling emergence and first leaf full expansion growth stages. Results from this study revealed transgressive phenotypic segregations for germination percentage and biomass at seedling stage. Twelve QTL were identified on chromosomes 2H–6H each explaining 10–25% of the phenotypic variations. A QTL located at 176.5 cM on chromosome 3H was linked with fresh weight per plant and dry weight per plant in salinity stress induced at first leaf full expansion growth stage, and dry weight per plant in salinity stress induced at seedling emergence. A stable QTL for germination at both 150 and 300 mM salinity stress was mapped on chromosome 2H but distantly located from a QTL linked with seedling stage salinity stress tolerance. QTL, associated markers and genotypes identified in this study play important roles in developing salinity stress tolerant barley varieties.

Background The dwarfing gene sdw1 has been widely used throughout the world to develop commercial barley varieties. There are at least four different alleles at the sdw1 locus. Results Mutations in the gibberellin 20-oxidase gene (HvGA20ox2) resulted in multiple alleles at the sdw1 locus. The sdw1.d allele from Diamant is due to a 7-bp deletion in exon 1, while the sdw1.c allele from Abed Denso has 1-bp deletion and a 4-bp insertion in the 5’ untranslated region. The sdw1.a allele from Jotun resulted from a total deletion of the HvGA20ox2 gene. The structural changes result in lower gene expression in sdw1.d and lack of expression in sdw1.a. There are three HvGA20ox genes in the barley genome. The partial or total loss of function of the HvGA20ox2 gene could be compensated by enhanced expression of its homolog HvGA20ox1and HvGA20ox3. A diagnostic molecular marker was developed to differentiate between the wild-type, sdw1.d and sdw1.a alleles and another molecular marker for differentiation of sdw1.c and sdw1.a. The markers were further tested in 197 barley varieties, out of which 28 had the sdw1.d allele and two varieties the sdw1.a allele. To date, the sdw1.d and sdw1.a alleles have only been detected in the modern barley varieties and lines. Conclusions The results provided further proof that the gibberellin 20-oxidase gene (HvGA20ox2) is the functional gene of the barley sdw1 mutants. Different deletions resulted in different functional alleles for different breeding purposes. Truncated protein could maintain partial function. Partial or total loss of function of the HvGA20ox2 gene could be compensated by enhanced expression of its homolog HvGA20ox1 and HvGA20ox3.

BACKGROUND: In the UK, the closure of 'long-stay' hospitals was accompanied by the development of community teams (CTs) to support people with intellectual disabilities (IDs) to live in community settings. The self-reported experiences of staff working in such teams have been neglected. METHODS: Focusing on a single county-wide service, comprising five multi-disciplinary and inter-agency CTs, we measured perceptions among the health care and care management Team members of (1) their personal well-being; (2) the functioning of their team; and (3) the organisation's commitment to quality, and culture. RESULTS: Almost three-quarters of the questionnaires were returned (73/101; 72%). The scores of health care practitioners and care managers were very similar: (1) the MBI scores of more than half the respondents were 'of concern'; (2) similarly, almost four in ten respondents' scores on the Vision scale of the TCI were 'of concern'; (3) the perceived commitment to quality (QIIS-II Part 2) was uncertain; and (4) the organisational culture (QIIS-II, Part 1) was viewed as primarily hierarchical. DISCUSSION: The perceived absence of a vision for the service, combined with a dominant culture viewed by its members as strongly focussed on bureaucracy and process, potentially compromises the ability of these CTs to respond proactively to the needs of people with IDs. Given the changes in legislation, policy and practice that have taken place since CTs were established, it would be timely to revisit their role and purpose.

A doubled haploid (DH) population of barley (Hordeum vulgare L.) generated from salinity tolerant genotype CM72 and salinity sensitive variety Gairdner was studied for salinity stress tolerance at germination, seedling emergence and first leaf full expansion growth stages. Germination study was conducted with deionized water, 150 mM and 300 mM NaCl treatments. Seedling stage salinity tolerance was conducted with three treatments: control, 150 mM NaCl added at seedling emergence and first leaf full expansion growth stages. Results from this study revealed transgressive phenotypic segregations for germination percentage and biomass at seedling stage. Twelve QTL were identified on chromosomes 2H–6H each explaining 10–25% of the phenotypic variations. A QTL located at 176.5 cM on chromosome 3H was linked with fresh weight per plant and dry weight per plant in salinity stress induced at first leaf full expansion growth stage, and dry weight per plant in salinity stress induced at seedling emergence. A stable QTL for germination at both 150 and 300 mM salinity stress was mapped on chromosome 2H but distantly located from a QTL linked with seedling stage salinity stress tolerance. QTL, associated markers and genotypes identified in this study play important roles in developing salinity stress tolerant barley varieties.

Background The dwarfing gene sdw1 has been widely used throughout the world to develop commercial barley varieties. There are at least four different alleles at the sdw1 locus. Results Mutations in the gibberellin 20-oxidase gene (HvGA20ox2) resulted in multiple alleles at the sdw1 locus. The sdw1.d allele from Diamant is due to a 7-bp deletion in exon 1, while the sdw1.c allele from Abed Denso has 1-bp deletion and a 4-bp insertion in the 5’ untranslated region. The sdw1.a allele from Jotun resulted from a total deletion of the HvGA20ox2 gene. The structural changes result in lower gene expression in sdw1.d and lack of expression in sdw1.a. There are three HvGA20ox genes in the barley genome. The partial or total loss of function of the HvGA20ox2 gene could be compensated by enhanced expression of its homolog HvGA20ox1and HvGA20ox3. A diagnostic molecular marker was developed to differentiate between the wild-type, sdw1.d and sdw1.a alleles and another molecular marker for differentiation of sdw1.c and sdw1.a. The markers were further tested in 197 barley varieties, out of which 28 had the sdw1.d allele and two varieties the sdw1.a allele. To date, the sdw1.d and sdw1.a alleles have only been detected in the modern barley varieties and lines. Conclusions The results provided further proof that the gibberellin 20-oxidase gene (HvGA20ox2) is the functional gene of the barley sdw1 mutants. Different deletions resulted in different functional alleles for different breeding purposes. Truncated protein could maintain partial function. Partial or total loss of function of the HvGA20ox2 gene could be compensated by enhanced expression of its homolog HvGA20ox1 and HvGA20ox3.

Leaf color is an important trait for not only controlling crop yield but also monitoring plant status under temperature stress. In this study, a thermo-inducible chlorophyll-deficient mutant, named V-V-Y, was identified from a gamma-radiated population of the barley variety Vlamingh. The leaves of the mutant were green under normal growing temperature but turned yellowish under high temperature in the glasshouse experiment. The ratio of chlorophyll a and chlorophyll b in the mutant declined much faster in the first 7–9 days under heat treatment. The leaves of V-V-Y turned yellowish but took longer to senesce under heat stress in the field experiment. Genetic analysis indicated that a single nuclear gene controlled the mutant trait. The mutant gene (vvy) was mapped to the long arm of chromosome 4H between SNP markers 1_0269 and 1_1531 with a genetic distance of 2.2 cM and a physical interval of 9.85 Mb. A QTL for grain yield was mapped to the same interval and explained 10.4% of the yield variation with a LOD score of 4. This QTL is coincident with the vvy gene interval that is responsible for the thermo-inducible chlorophyll-deficient trait. Fine mapping, based on the barley reference genome sequence, further narrowed the vvy gene to a physical interval of 0.428 Mb with 11 annotated genes. This is the first report of fine mapping a thermo-inducible chlorophyll-deficient gene in barley.

Background: Barley semi-dwarf genes have been extensively explored and widely used in barley breeding programs. The semi-dwarf gene ari-e from Golden Promise is an important gene associated with some agronomic traits and salt tolerance. While ari-e has been mapped on barley chromosome 5H using traditional markers and next-generation sequencing technologies, it has not yet been finely located on this chromosome. Results: We integrated two methods to develop molecular markers for fine-mapping the semi-dwarf gene ari-e: (1) specific-length amplified fragment sequencing (SLAF-seq) with bulked segregant analysis (BSA) to develop SNP markers, and (2) the whole-genome shotgun sequence to develop InDels. Both SNP and InDel markers were developed in the target region and used for fine-mapping the ari-e gene. Linkage analysis showed that ari-e co-segregated with marker InDel-17 and was delimited by two markers (InDel-16 and DGSNP21) spanning 6.8 cM in the doubled haploid (DH) Dash × VB9104 population. The genetic position of ari-e was further confirmed in the Hindmarsh × W1 DH population which was located between InDel-7 and InDel-17. As a result, the overlapping region of the two mapping populations flanked by InDel-16 and InDel-17 was defined as the candidate region spanning 0.58 Mb on the POPSEQ physical map. Conclusions: The current study demonstrated the SLAF-seq for SNP discovery and whole-genome shotgun sequencing for InDel development as an efficient approach to map complex genomic region for isolation of functional gene. The ari-e gene was fine mapped from 10 Mb to 0.58 Mb interval.

Genome-wide association studies (GWAS) based on linkage disequilibrium (LD) have been used to detect QTLs underlying complex traits in major crops. In this study, we collected 218 barley (Hordeum vulgare L.) lines including wild barley and cultivated barley from China, Canada, Australia, and Europe. A total of 408 polymorphic markers were used for population structure and LD analysis. GWAS for acid soil resistance were performed on the population using a general linkage model (GLM) and a mixed linkage model (MLM), respectively. A total of 22 QTLs (quantitative trait loci) were detected with the GLM and MLM analyses. Two QTLs, close to markers bPb-1959 (133.1 cM) and bPb-8013 (86.7 cM), localized on chromosome 1H and 4H respectively, were consistently detected in two different trials with both the GLM and MLM analyses. Furthermore, bPb-8013, the closest marker to the major Al3+ resistance gene HvAACT1 in barley, was identified to be QTL5. The QTLs could be used in marker-assisted selection to identify and pyramid different loci for improved acid soil resistance in barley.

Background: Barley semi-dwarf genes have been extensively explored and widely used in barley breeding programs. The semi-dwarf gene ari-e from Golden Promise is an important gene associated with some agronomic traits and salt tolerance. While ari-e has been mapped on barley chromosome 5H using traditional markers and next-generation sequencing technologies, it has not yet been finely located on this chromosome. Results: We integrated two methods to develop molecular markers for fine-mapping the semi-dwarf gene ari-e: (1) specific-length amplified fragment sequencing (SLAF-seq) with bulked segregant analysis (BSA) to develop SNP markers, and (2) the whole-genome shotgun sequence to develop InDels. Both SNP and InDel markers were developed in the target region and used for fine-mapping the ari-e gene. Linkage analysis showed that ari-e co-segregated with marker InDel-17 and was delimited by two markers (InDel-16 and DGSNP21) spanning 6.8 cM in the doubled haploid (DH) Dash × VB9104 population. The genetic position of ari-e was further confirmed in the Hindmarsh × W1 DH population which was located between InDel-7 and InDel-17. As a result, the overlapping region of the two mapping populations flanked by InDel-16 and InDel-17 was defined as the candidate region spanning 0.58 Mb on the POPSEQ physical map. Conclusions: The current study demonstrated the SLAF-seq for SNP discovery and whole-genome shotgun sequencing for InDel development as an efficient approach to map complex genomic region for isolation of functional gene. The ari-e gene was fine mapped from 10 Mb to 0.58 Mb interval.

Genome-wide association studies (GWAS) based on linkage disequilibrium (LD) have been used to detect QTLs underlying complex traits in major crops. In this study, we collected 218 barley (Hordeum vulgare L.) lines including wild barley and cultivated barley from China, Canada, Australia, and Europe. A total of 408 polymorphic markers were used for population structure and LD analysis. GWAS for acid soil resistance were performed on the population using a general linkage model (GLM) and a mixed linkage model (MLM), respectively. A total of 22 QTLs (quantitative trait loci) were detected with the GLM and MLM analyses. Two QTLs, close to markers bPb-1959 (133.1 cM) and bPb-8013 (86.7 cM), localized on chromosome 1H and 4H respectively, were consistently detected in two different trials with both the GLM and MLM analyses. Furthermore, bPb-8013, the closest marker to the major Al3+ resistance gene HvAACT1 in barley, was identified to be QTL5. The QTLs could be used in marker-assisted selection to identify and pyramid different loci for improved acid soil resistance in barley.

Thrips are small insects that cause direct damage and some transmit viruses to agricultural and horticultural crops and forest trees. Current thrips management requires a significant input of agrichemicals, which creates risks for workers, consumers and the environment. As well, a number of thrips species are of significant quarantine concern. New thrips management strategies are urgently needed to supplement existing tools such as chemical and biological pesticides. For example, semiochemical-based technologies could serve as additional management tools, since they have proved their efficiency at controlling many large insect pests. However, these technologies have been under-exploited for small insects such as thrips. To address this issue, an international network was initiated in 2012, the focus of this Europe Australasian Thrips Semiochemical Network (EATS) is to develop semiochemical-based tools for management of thrips. The progress made in this field is reported in the following paper.

Background: Acid soil is a serious limitation to crop production all over the world. Toxic aluminium (Al) cations in acid soil inhibit root growth and reduce yield. Although a gene tolerant to acid soil has been identified, it has not been used in malting barley breeding, which is partly due to the acid soil tolerance gene being linked to unfavorable malting quality traits. Results: A Brazilian malting barley variety Br2 was identified as tolerant to acid soil. A doubled haploid (DH) population was developed from a cross between Br2 and the Australian acid-sensitive cultivar Hamelin. The DH population was tested for acid soil tolerance in native acid soil and a hydroponic system with pH 4.2, pH 4.2 + Al or pH 6.5, and genotyped using SSR, DArT and gene-specific markers. A single QTL was detected for all parameters related to acid soil tolerance. The QTL was mapped to the known HvMATE location on chromosome 4H. Sequence alignment of the HvMATE gene identified 13 INDELs and 87 SNPs, where one SNP coded for a single amino acid difference between the two varieties. A gene-specific marker was developed to detect the single nucleotide polymorphism between Hamelin and Br2. This marker co-segregated with aluminium tolerance and accounted for 79 % of phenotypic variation for acid soil tolerance. Conclusion: The present study identified a novel source of acid soil/Al tolerance from a Brazilian malting barley cultivar Br2. This variety tolerated Al toxicity but was sensitive to low pH which is similar to most other Al-tolerant varieties. A gene-specific marker Cit7 was developed based on the HvMATE gene sequence. Cit7 will improve the efficiency of molecular-assisted selection of new barley varieties with tolerance to acid soil. Multiple alleles exist for the acid soil tolerance gene on chromosome 4H, so a malting barley variety that tolerates acid soil could be developed by selecting suitable tolerant alleles. Tolerance to low pH may play an important role for barley to adapt

Tolerance to waterlogging is an important breeding objective for barley (Hordeum vulgare L.); however, it is a complex quantitative trait. It is difficult to screen large numbers of lines in the field due to environmental variability, and it is also challenging to screen large numbers in controlled conditions if yield data are to be collected. The direct measurement of traits that contribute to waterlogging tolerance, such as aerenchyma development in roots, may offer advantages especially if molecular markers can be developed to screen breeding populations. A doubled haploid population from a cross between Franklin and YuYaoXiangTian Erleng was screened for adventitious root porosity (gas-filled volume per unit root volume) as an indicator of aerenchyma formation. A single QTL for root porosity was identified on chromosome 4H which explained 35.7 and 39.0 % of phenotypic variation in aerated and oxygen-deficient conditions, respectively. The nearest marker was EBmac0701. This QTL is located in the same chromosomal region that contributed to tolerance when the same population was screened in an earlier independent soil waterlogging experiment. Comparative mapping revealed that this QTL is syntenic with the Qaer1.02-3 QTL in maize and the Sub1A-1 gene in rice, which are associated with aerenchyma formation (maize) and submergence tolerance (rice), respectively. This is the first report of a QTL for root porosity in barley which elucidates a major mechanism of waterlogging tolerance.

Background: Acid soil is a serious limitation to crop production all over the world. Toxic aluminium (Al) cations in acid soil inhibit root growth and reduce yield. Although a gene tolerant to acid soil has been identified, it has not been used in malting barley breeding, which is partly due to the acid soil tolerance gene being linked to unfavorable malting quality traits. Results: A Brazilian malting barley variety Br2 was identified as tolerant to acid soil. A doubled haploid (DH) population was developed from a cross between Br2 and the Australian acid-sensitive cultivar Hamelin. The DH population was tested for acid soil tolerance in native acid soil and a hydroponic system with pH 4.2, pH 4.2 + Al or pH 6.5, and genotyped using SSR, DArT and gene-specific markers. A single QTL was detected for all parameters related to acid soil tolerance. The QTL was mapped to the known HvMATE location on chromosome 4H. Sequence alignment of the HvMATE gene identified 13 INDELs and 87 SNPs, where one SNP coded for a single amino acid difference between the two varieties. A gene-specific marker was developed to detect the single nucleotide polymorphism between Hamelin and Br2. This marker co-segregated with aluminium tolerance and accounted for 79 % of phenotypic variation for acid soil tolerance. Conclusion: The present study identified a novel source of acid soil/Al tolerance from a Brazilian malting barley cultivar Br2. This variety tolerated Al toxicity but was sensitive to low pH which is similar to most other Al-tolerant varieties. A gene-specific marker Cit7 was developed based on the HvMATE gene sequence. Cit7 will improve the efficiency of molecular-assisted selection of new barley varieties with tolerance to acid soil. Multiple alleles exist for the acid soil tolerance gene on chromosome 4H, so a malting barley variety that tolerates acid soil could be developed by selecting suitable tolerant alleles. Tolerance to low pH may play an important role for barley to adapt

Tolerance to waterlogging is an important breeding objective for barley (Hordeum vulgare L.); however, it is a complex quantitative trait. It is difficult to screen large numbers of lines in the field due to environmental variability, and it is also challenging to screen large numbers in controlled conditions if yield data are to be collected. The direct measurement of traits that contribute to waterlogging tolerance, such as aerenchyma development in roots, may offer advantages especially if molecular markers can be developed to screen breeding populations. A doubled haploid population from a cross between Franklin and YuYaoXiangTian Erleng was screened for adventitious root porosity (gas-filled volume per unit root volume) as an indicator of aerenchyma formation. A single QTL for root porosity was identified on chromosome 4H which explained 35.7 and 39.0 % of phenotypic variation in aerated and oxygen-deficient conditions, respectively. The nearest marker was EBmac0701. This QTL is located in the same chromosomal region that contributed to tolerance when the same population was screened in an earlier independent soil waterlogging experiment. Comparative mapping revealed that this QTL is syntenic with the Qaer1.02-3 QTL in maize and the Sub1A-1 gene in rice, which are associated with aerenchyma formation (maize) and submergence tolerance (rice), respectively. This is the first report of a QTL for root porosity in barley which elucidates a major mechanism of waterlogging tolerance.

Thrips are small insects that cause direct damage and some transmit viruses to agricultural and horticultural crops and forest trees. Current thrips management requires a significant input of agrichemicals, which creates risks for workers, consumers and the environment. As well, a number of thrips species are of significant quarantine concern. New thrips management strategies are urgently needed to supplement existing tools such as chemical and biological pesticides. For example, semiochemical-based technologies could serve as additional management tools, since they have proved their efficiency at controlling many large insect pests. However, these technologies have been under-exploited for small insects such as thrips. To address this issue, an international network was initiated in 2012, the focus of this Europe Australasian Thrips Semiochemical Network (EATS) is to develop semiochemical-based tools for management of thrips. The progress made in this field is reported in the following paper.

Rhynchosporium secalis can overcome a single resistance gene of barley in a relatively short period of time. Novel genes and quantitative trait locis (QTLs) are therefore vital to control scald in barley. A population of 220 double haploid lines was developed from a cross of Vlamingh and WABAR2147, where Vlamingh showed adult plant resistance (APR) and WABAR2147 showed seedling resistance to a group of isolates. The population was tested for APR to scald under natural infection in two consecutive seasons in addition to a seedling screen with three isolates. One single gene was mapped to chromosome 6H based on the seedling test, and two QTLs (QSc.VlWa.4H and QSc.VlWa.6H) were mapped to chromosomes 4H and 6H based on APR. Epistatic interaction was observed between the two QTLs, and environment/QTL interaction was only observed for QSc.VlWa.6H which co-segregated with the seedling resistance gene and contributed to basal resistance against scald during whole growth stages. QSc.VlWa.4H explained 42.5 and 57.8 % of the phenotypic variation in the two independent trials when the effect of QSc.VlWa.6H was excluded from the analysis. We developed a high-density consensus genetic map with 7,876 molecular makers and anchored 43 QTLs and 7 genes for scald resistance from different mapping populations. No known QTLs or genes were reported in a similar position to QSc.VlWa.4H, and it was the first major QTL for APR of scald on chromosome 4HS in barley. Combination of the two QTLs achieved better and stable scald resistance across four different environments.

Proteins in barley grains are determinants of beer quality, which are modified during malting to provide nutrition for yeast during brewing. Different malting barley varieties behave differently during malting. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to characterize storage proteins including albumin, globulin, hordein and glutelin in grains and malt of parental varieties and a doubled haploid (DH) population. Each parental variety produces malt with particular quality profiles. The protein profiles of analyzed extracts in seed and malt were compared to find the most influenced proteins during the malting process. Our results revealed that malting procedure dramatically affected the composition and amounts of albumin, then hordein, glutelin and globulin in barley. Moreover, hordein and glutelin profiles in the DH population exhibited high levels of polymorphism. The genetic information represented by individual hordein and glutelin profiles was successfully mapped as molecular markers in a genetic linkage map. Twelve and 8 (hordein in seed and malt, respectively) or 10 and 8 (glutelin in seed and malt, respectively) segregating peaks were scored as polymorphic across the population, and all peaks were located to the chromosome 1H. The MALDI-TOF MS provides a method with high resolution and throughput to characterize mass patterns of extracted storage proteins in barley and malt.

Rhynchosporium secalis can overcome a single resistance gene of barley in a relatively short period of time. Novel genes and quantitative trait locis (QTLs) are therefore vital to control scald in barley. A population of 220 double haploid lines was developed from a cross of Vlamingh and WABAR2147, where Vlamingh showed adult plant resistance (APR) and WABAR2147 showed seedling resistance to a group of isolates. The population was tested for APR to scald under natural infection in two consecutive seasons in addition to a seedling screen with three isolates. One single gene was mapped to chromosome 6H based on the seedling test, and two QTLs (QSc.VlWa.4H and QSc.VlWa.6H) were mapped to chromosomes 4H and 6H based on APR. Epistatic interaction was observed between the two QTLs, and environment/QTL interaction was only observed for QSc.VlWa.6H which co-segregated with the seedling resistance gene and contributed to basal resistance against scald during whole growth stages. QSc.VlWa.4H explained 42.5 and 57.8 % of the phenotypic variation in the two independent trials when the effect of QSc.VlWa.6H was excluded from the analysis. We developed a high-density consensus genetic map with 7,876 molecular makers and anchored 43 QTLs and 7 genes for scald resistance from different mapping populations. No known QTLs or genes were reported in a similar position to QSc.VlWa.4H, and it was the first major QTL for APR of scald on chromosome 4HS in barley. Combination of the two QTLs achieved better and stable scald resistance across four different environments.

Proteins in barley grains are determinants of beer quality, which are modified during malting to provide nutrition for yeast during brewing. Different malting barley varieties behave differently during malting. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to characterize storage proteins including albumin, globulin, hordein and glutelin in grains and malt of parental varieties and a doubled haploid (DH) population. Each parental variety produces malt with particular quality profiles. The protein profiles of analyzed extracts in seed and malt were compared to find the most influenced proteins during the malting process. Our results revealed that malting procedure dramatically affected the composition and amounts of albumin, then hordein, glutelin and globulin in barley. Moreover, hordein and glutelin profiles in the DH population exhibited high levels of polymorphism. The genetic information represented by individual hordein and glutelin profiles was successfully mapped as molecular markers in a genetic linkage map. Twelve and 8 (hordein in seed and malt, respectively) or 10 and 8 (glutelin in seed and malt, respectively) segregating peaks were scored as polymorphic across the population, and all peaks were located to the chromosome 1H. The MALDI-TOF MS provides a method with high resolution and throughput to characterize mass patterns of extracted storage proteins in barley and malt.

The minimum genus problem consists on determining the minimum algebraic genus of a surface on which a given group G acts. For cyclic groups G this problem on bordered Klein surfaces was solved in 1989. The next step is to fix the number of boundary components of the surface and to obtain the minimum algebraic genus, and so the minimum topological genus. It was achieved for cyclic groups of prime and prime-power order in the nineties. In this work the corresponding results for cyclic groups of order N = 2q, where q is an odd prime, are obtained. There appear different results depending on the orientability of the surface. Finally, using the above mentioned results and those of this paper, we state explicitly, the general values for arbitrary number of boundary components, which are valid for each N < 12, and show how to deal with N = 12.

Basic vegetative period (BVP) is an important trait for determining flowering time and adaptation to variable environments. A short BVP barley mutant is about 30 d shorter than its wild type. Genetic analysis using 557 F2 individuals revealed that the short BVP is governed by a single recessive gene (BVP-1) and was further validated in 2 090 F3 individuals. The BVP-1 gene was first mapped to barley chromosome 1H using SSR markers. Comparative genomic analysis demonstrated that the chromosome region of BVP-1 is syntenic to rice chromosome 5 and Brachypodium chromosome 2. Barley ESTs/genes were identified after comparison with candidate genes in rice and Brachypodium; seven new gene-specific markers were developed and mapped in the mapping populations. The BVP-1 gene co-segregated with the Mot1 and Ftsh4 genes and was flanked by the gene-specific markers AK252360 (0.2 cM) and CA608558 (0.5 cM). Further analysis demonstrated that barley and wheat share the same short BVP gene controlling early flowering.

Acid soil/aluminium toxicity is one of the major constraints on barley production around the world. Genetic improvement is the best solution and molecular-marker-assisted selection has proved to be an efficient tool for developing barley cultivars with acid soil/aluminium tolerance. In this study, barley variety Svanhals-introduced from CYMMIT (International Maize and Wheat Improvement Center)-was identified as acid soil/aluminium tolerant and the tolerance was mapped to chromosome 4H in 119 doubled haploid (DH) lines from a cross of Hamelin/Svanhals. The HvMATE gene, encoding an aluminium-activated citrate transporter, was selected as a candidate gene and gene-specific molecular markers were developed to detect acid soil/aluminium tolerance based on the polymerase chain reaction. Sequence analysis of the HvMATE gene identified a 21-bp indel (insertion-deletion) between the tolerant and sensitive cultivars. The new marker was further mapped to the QTL (quantitative trait loci) region on chromosome 4H for acid soil tolerance and accounted for 66.9 % of phenotypic variation in the DH population. Furthermore, the polymorphism was confirmed in other tolerant varieties which have been widely used as a source of acid soil tolerance in Australian barley breeding programs. The new gene-specific molecular marker provides an effective and simple molecular tool for selecting the acid soil tolerance gene from multiple tolerance sources.

Basic vegetative period (BVP) is an important trait for determining flowering time and adaptation to variable environments. A short BVP barley mutant is about 30 d shorter than its wild type. Genetic analysis using 557 F2 individuals revealed that the short BVP is governed by a single recessive gene (BVP-1) and was further validated in 2 090 F3 individuals. The BVP-1 gene was first mapped to barley chromosome 1H using SSR markers. Comparative genomic analysis demonstrated that the chromosome region of BVP-1 is syntenic to rice chromosome 5 and Brachypodium chromosome 2. Barley ESTs/genes were identified after comparison with candidate genes in rice and Brachypodium; seven new gene-specific markers were developed and mapped in the mapping populations. The BVP-1 gene co-segregated with the Mot1 and Ftsh4 genes and was flanked by the gene-specific markers AK252360 (0.2 cM) and CA608558 (0.5 cM). Further analysis demonstrated that barley and wheat share the same short BVP gene controlling early flowering.

Acid soil/aluminium toxicity is one of the major constraints on barley production around the world. Genetic improvement is the best solution and molecular-marker-assisted selection has proved to be an efficient tool for developing barley cultivars with acid soil/aluminium tolerance. In this study, barley variety Svanhals-introduced from CYMMIT (International Maize and Wheat Improvement Center)-was identified as acid soil/aluminium tolerant and the tolerance was mapped to chromosome 4H in 119 doubled haploid (DH) lines from a cross of Hamelin/Svanhals. The HvMATE gene, encoding an aluminium-activated citrate transporter, was selected as a candidate gene and gene-specific molecular markers were developed to detect acid soil/aluminium tolerance based on the polymerase chain reaction. Sequence analysis of the HvMATE gene identified a 21-bp indel (insertion-deletion) between the tolerant and sensitive cultivars. The new marker was further mapped to the QTL (quantitative trait loci) region on chromosome 4H for acid soil tolerance and accounted for 66.9 % of phenotypic variation in the DH population. Furthermore, the polymorphism was confirmed in other tolerant varieties which have been widely used as a source of acid soil tolerance in Australian barley breeding programs. The new gene-specific molecular marker provides an effective and simple molecular tool for selecting the acid soil tolerance gene from multiple tolerance sources.

The risk factors for and clinical features of bloodstream infection with uncommon Candida spp. (species other than C. albicans, C. glabrata, C. parapsilosis, C. tropicals and C. krusei) are incompletely defined. To identify clinical variables associated with these species that might guide management, 57 cases of candidaemia resulting from uncommon Candida spp. were analysed in comparison with 517 episodes of Candida albicans candidaemia (2001-2004). Infection with uncommon Candida spp. (5.3% of candidaemia cases), as compared with C. albicans candidaemia, was significantly more likely to be outpatient-acquired than inpatient-acquired (15 of 57 vs. 65 of 517 episodes, p0.01). Prior exposure to fluconazole was uncommon (n =1). Candida dubliniensis was the commonest species (n =22, 39%), followed by Candida guilliermondii (n = 11, 19%) and Candida lusitaniae (n = 7, 12%). C. dubliniensis candidaemia was independently associated with recent intravenous drug use (p0.01) and chronic liver disease (p0.03), and infection with species other than C. dubliniensis was independently associated with age <65 years (p0.02), male sex (p0.03) and human immunodeficiency virus infection (p0.05). Presence of sepsis at diagnosis and crude 30-day mortality rates were similar for C. dubliniensis-related, non- C. dubliniensis-related and C. albicans-related candidaemia. Haematological malignancy was the commonest predisposing factor in C. guilliermondii (n = 3, 27%) and C. lusitaniae (n = 3, 43%) candidaemia. The 30-day mortality rate of C. lusitaniae candidaemia was higher than the overall death rate for all uncommon Candida spp. (42.9% vs. 25%, not significant). All isolates were susceptible to amphotericin.B, voriconazole, posaconazole, and caspofungin; five strains (9%) had fluconazole MIC values of 16-32 mg/L. Candidaemia due to uncommon Candida spp. is emerging among hospital outpatients; certain clinical variables may assist in recognition of this entity. © 2009 The Authors Journal c

Population-based surveillance for candidemia in Australia from 2001 to 2004 identified 1,095 cases. Annual overall and hospital-specific incidences were 1.81/100,000 and 0.21/1,000 separations (completed admissions), respectively. Predisposing factors included malignancy (32.1%), indwelling vascular catheters (72.6%), use of antimicrobial agents (77%), and surgery (37.1%). Of 919 episodes, 81.5% were inpatient healthcare associated (IHCA), 11.6% were outpatient healthcare associated (OHCA), and 6.9% were community acquired (CA). Concomitant illnesses and risk factors were similar in IHCA and OHCA candidemia. IHCA candidemia was associated with sepsis at diagnosis (p<0.001), death <=30 days after infection (p<0.001), and prolonged hospital admission (p<0.001). Non-Candida albicans species (52.7%) caused 60.5% of cases acquired outside hospitals and 49.9% of IHCA candidemia (p = 0.02). The 30-day death rate was 27.7% in those >=65 years of age. Adult critical care stay, sepsis syndrome, and corticosteroid therapy were associated with the greatest risk for death. Systematic epidemiologic studies that use standardized definitions for IHCA, OHCA, and CA candidemia are indicated.

The association between high malting quality and pre-harvest sprouting (PHS) susceptibility is a key challenge when developing new malting barley varieties. A new malting barley variety Baudin has successfully combined high malting quality and PHS tolerance. A doubled haploid population was developed for mapping PHS tolerance and seed dormancy from a cross of Baudin × AC Metcalfe using 233 molecular markers. Three QTLs were mapped for seed dormancy based on the standard germination test at 24, 48 and 72 h. One major QTL was mapped to the long arm of chromosome 5H controlling seed dormancy and PHS tolerance from Baudin. Two other minor QTLs were identified from Baudin on chromosomes 3 and 7H. QTL/QTL interaction was detected for seed dormancy between chromosomes 3 and 5H. The PHS tolerance allele of the 5H QTL from Baudin contributes to higher malt yield without significant impact on diastatic power, beta-glucan content and wort viscosity. QTL from Baudin provide new sources to integrate PHS tolerance and high malting quality.

Photoperiod response is a key determinant for barley adaptation to diverse environments. A major quantitative trait locus (QTL) for response to long photoperiod was identified in Australia (Perth, 31A degrees 56'S) and China (Wuhan, 30A degrees 33'N) using 178 doubled haploid lines derived from a cross of an Australian barley, Baudin, and a Canadian barley, AC Metcalfe. The QTL was detected as a major QTL in the 18-h photoperiod glasshouse experiments and mapped to the Xp12m50B199-Xp13m47B399 interval on chromosome 4H with a LOD score of 57 in Australia and confirmed in China. The single QTL accounted for 77.48 and 37.81% of phenotypic variation for long photoperiod response in Australia and China, respectively. The same QTL also controlled heading date in Australia, under normal and extended photoperiod conditions, and in China, under extended photoperiod and late-sown conditions. The QTL advanced heading date by 27.8 days in Australia and 42.5 days in China under a 18-h photoperiod. In addition, QTL for heading date were identified on chromosomes 2H and 3H. The chromosome 3H QTL was associated with the denso gene and detected in all conditions, but the chromosome 2H QTL was only detected in Australia. The new photoperiod response QTL, Qhea.BM.4-13/Qpho.BM.4-13, on chromosome 4H and its associated markers will provide an alternative for plant breeders developing new varieties for different environments using marker-assisted selection.

The risk factors for and clinical features of bloodstream infection with uncommon Candida spp. (species other than C. albicans, C. glabrata, C. parapsilosis, C. tropicals and C. krusei) are incompletely defined. To identify clinical variables associated with these species that might guide management, 57 cases of candidaemia resulting from uncommon Candida spp. were analysed in comparison with 517 episodes of Candida albicans candidaemia (2001-2004). Infection with uncommon Candida spp. (5.3% of candidaemia cases), as compared with C. albicans candidaemia, was significantly more likely to be outpatient-acquired than inpatient-acquired (15 of 57 vs. 65 of 517 episodes, p0.01). Prior exposure to fluconazole was uncommon (n =1). Candida dubliniensis was the commonest species (n =22, 39%), followed by Candida guilliermondii (n = 11, 19%) and Candida lusitaniae (n = 7, 12%). C. dubliniensis candidaemia was independently associated with recent intravenous drug use (p0.01) and chronic liver disease (p0.03), and infection with species other than C. dubliniensis was independently associated with age <65 years (p0.02), male sex (p0.03) and human immunodeficiency virus infection (p0.05). Presence of sepsis at diagnosis and crude 30-day mortality rates were similar for C. dubliniensis-related, non- C. dubliniensis-related and C. albicans-related candidaemia. Haematological malignancy was the commonest predisposing factor in C. guilliermondii (n = 3, 27%) and C. lusitaniae (n = 3, 43%) candidaemia. The 30-day mortality rate of C. lusitaniae candidaemia was higher than the overall death rate for all uncommon Candida spp. (42.9% vs. 25%, not significant). All isolates were susceptible to amphotericin.B, voriconazole, posaconazole, and caspofungin; five strains (9%) had fluconazole MIC values of 16-32 mg/L. Candidaemia due to uncommon Candida spp. is emerging among hospital outpatients; certain clinical variables may assist in recognition of this entity. © 2009 The Authors Journal c

Population-based surveillance for candidemia in Australia from 2001 to 2004 identified 1,095 cases. Annual overall and hospital-specific incidences were 1.81/100,000 and 0.21/1,000 separations (completed admissions), respectively. Predisposing factors included malignancy (32.1%), indwelling vascular catheters (72.6%), use of antimicrobial agents (77%), and surgery (37.1%). Of 919 episodes, 81.5% were inpatient healthcare associated (IHCA), 11.6% were outpatient healthcare associated (OHCA), and 6.9% were community acquired (CA). Concomitant illnesses and risk factors were similar in IHCA and OHCA candidemia. IHCA candidemia was associated with sepsis at diagnosis (p<0.001), death <=30 days after infection (p<0.001), and prolonged hospital admission (p<0.001). Non-Candida albicans species (52.7%) caused 60.5% of cases acquired outside hospitals and 49.9% of IHCA candidemia (p = 0.02). The 30-day death rate was 27.7% in those >=65 years of age. Adult critical care stay, sepsis syndrome, and corticosteroid therapy were associated with the greatest risk for death. Systematic epidemiologic studies that use standardized definitions for IHCA, OHCA, and CA candidemia are indicated.

The association between high malting quality and pre-harvest sprouting (PHS) susceptibility is a key challenge when developing new malting barley varieties. A new malting barley variety Baudin has successfully combined high malting quality and PHS tolerance. A doubled haploid population was developed for mapping PHS tolerance and seed dormancy from a cross of Baudin × AC Metcalfe using 233 molecular markers. Three QTLs were mapped for seed dormancy based on the standard germination test at 24, 48 and 72 h. One major QTL was mapped to the long arm of chromosome 5H controlling seed dormancy and PHS tolerance from Baudin. Two other minor QTLs were identified from Baudin on chromosomes 3 and 7H. QTL/QTL interaction was detected for seed dormancy between chromosomes 3 and 5H. The PHS tolerance allele of the 5H QTL from Baudin contributes to higher malt yield without significant impact on diastatic power, beta-glucan content and wort viscosity. QTL from Baudin provide new sources to integrate PHS tolerance and high malting quality.