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Deodoro A Brandao - One of the best experts on this subject based on the ideXlab platform.
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ergasilus Thatcheri n sp copepoda poecilostomatoida ergasilidae from the gills of rhamdia quelen teleostei siluriformes pimelodidae from southern brazil
Journal of Parasitology, 2000Co-Authors: Kerlen B Engers, Deodoro A Brandao, Walter A. BoegerAbstract:The female of Ergasilus Thatcheri n. sp. (Copepoda, Poecilostomatoida, Ergasilidae) is described from the gills of the “jundia,” Rhamdia quelen (Teleostei, Siluriformes, Pimelodidae), from fish ponds in the State of Rio Grande do Sul, Brazil. The new species has a falciform semipinnate terminal seta on the first exopod, which suggests phylogenetic affinity to 10 other congeners, all from fishes of the Amazon Basin. Based on general morphology, the new species shows great similarity to E. callophysus Thatcher and Boeger, 1984, a parasite of another pimelodid fish Callophysus macropterus. Ergasilus Thatcheri n. sp., however, can be easily differentiated from E. callophysus in its possession of a more distal sensillum not located on a cuticular elevation, and a row of spinules on the inner margin of the second antennal segment (first endopodal segment).
Matthew N Rouse - One of the best experts on this subject based on the ideXlab platform.
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complementary epistasis involving sr12 explains adult plant resistance to stem rust in Thatcher wheat triticum aestivum l
Theoretical and Applied Genetics, 2014Co-Authors: Matthew N Rouse, L E Talbert, Davinder Singh, J D ShermanAbstract:Key message Quantitative trait loci conferring adult plant resistance to Ug99 stem rust in Thatcher wheat display complementary gene action suggesting multiple quantitative trait loci are needed for effective resistance. Abstract Adult plant resistance (APr) in wheat (Triticum aestivum l.) to stem rust, caused by Puccinia graminis f. sp. tritici (Pgt), is desirable because this resistance can be Pgt race non-specific. resistance derived from cultivar Thatcher can confer high levels of APr to the virulent Pgt race TTKSK (Ug99) when combined with stem rust resist- ance gene Sr57 (Lr34). To identify the loci conferring APr in Thatcher, we evaluated 160 rIls derived from Thatcher crossed to susceptible cultivar Mcneal for field stem rust
J. A. Kolmer - One of the best experts on this subject based on the ideXlab platform.
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Thatcher wheat line rl6149 carries lr64 and a second leaf rust resistance gene on chromosome 1ds
Theoretical and Applied Genetics, 2019Co-Authors: J. A. Kolmer, Matthew J Hayden, Amy Bernardo, Guihua Bai, James A AndersonAbstract:KEY MESSAGE The leaf rust resistance gene Lr64 in the Thatcher wheat RL6149 was mapped to chromosome 6AL with SNP and KASP markers and a second leaf rust resistance gene was mapped to chromosome 1DS. RL6149, a near-isogenic line of Thatcher wheat, carries leaf rust resistance gene Lr64 on chromosome arm 6AL. The objective of this study was to develop molecular markers that can be easily used to select wheat lines with Lr64. RL6149 was crossed with Thatcher and F2 plants derived from a single F1 plant were advanced to F6 lines by single seed descent. The 100 F7 recombinant inbred lines (RIL) were inoculated with two races of P.triticina that differed widely for virulence in order to identify resistant and susceptible RIL. Thirty RIL that differed for resistance and the parental lines were genotyped with the 90 K Infinium iSelect single nucleotide polymorphism (SNP) array to find closely linked markers with Lr64. Seven linked SNPs on chromosome arm 6AL were converted into Kompetitive Allele Specific PCR (KASP) markers that were genotyped on the 100 RIL. A genetic linkage map for the seven KASP markers spanned 19.1 cM on chromosome arm 6AL. KASP marker K-IWB59855 was tightly linked to Lr64. A second unexpected gene for leaf rust resistance also segregated in the F7 lines. Four KASP markers that spanned 18.6 cM located the gene on chromosome 1DS. The KASP marker K-IWB38437 was tightly linked to the second leaf rust resistance gene.
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genetics of stem rust resistance in the spring wheat cultivar Thatcher and the enhancement of stem rust resistance by lr34
Euphytica, 2008Co-Authors: Carmen Gavin D Vanegas, David F. Garvin, J. A. KolmerAbstract:Three recombinant inbred line populations from the crosses RL6071/Thatcher, RL6071/RL6058 (Thatcher Lr34), and Thatcher/RL6058, were used to study the genetics of stem rust resistance in Thatcher and TcLr34. Segregation of stem rust response in each population was used to determine the number of genes conferring resistance, as well as the effect of the leaf rust resistance gene Lr34 on stem rust resistance. The relationship between resistance in seedling and adult plants was also examined, and an attempt was made to identify microsatellite markers linked to genes that were effective in adult plants. In field plot tests at least three additive resistance genes segregated in the RL6071/RL6058 population, whereas two resistance genes segregated in the RL6071/Thatcher population. The presence of the gene Lr34 permitted the expression of additional stem rust resistance in Thatcher-derived lines both at the seedling and adult plant stages. Seedling resistance to races TPMK and RKQQ was significantly associated with resistance in adult plants, whereas seedling resistance to races QCCD and QCCB may have made a minor contribution. The seedling resistance genes Sr16 and Sr12 may have contributed to resistance in adult plants. A molecular marker linked to resistance in adult plants was identified on chromosome 2BL.
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Genetics of leaf rust resistance in three Western Canada spring wheats
Plant Disease, 1994Co-Authors: J. A. KolmerAbstract:The wheat cultivars Laura, Biggar, and Genesis have recently been licensed and released for production in western Canada. These cultivars all have effective resistance to the wheat leaf rust fungus, Puccinia recondita f. sp. tritici. The objective of this study was to identify the leaf rust resistance genes in these cultivars. The three cultivars were crossed with the leaf rust-susceptible cultivar Thatcher and also with near-isogenic lines of Thatcher with known leaf rust resistance genes. Segregation of F 3 lines in an artificially inoculated rust nursery indicated that Laura has the adult plant gene Lr34. The seedling resistance genes Lr1 and Lr10 were also identified in Laura. Segregation of F 3 lines indicated that the adult plant gene Lr13 was in Genesis and Biggar [...]
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Selection in a heterogeneous population of Puccinia recondita f. sp. tritici
Phytopathology, 1993Co-Authors: J. A. KolmerAbstract:A heterogeneous population of Puccinia recondita f. sp. tritici developed from randomly mated pycnial infections on Thalictrum speciosissimum was selected for 12 generations on four wheat lines with different resistance genes to determine if unnecessary genes for virulence were deleterious to general levels of fitness in the wheat leaf rust fungus. Diversity of virulence phenotypes, as measured with the Shannon index, declined least in the population selected on the susceptible line Thatcher and most in the population selected on the resistant cultivar Roblin (Lr1, Lr10, Lr13, and Lr34). Phenotypes with virulence to six differential lines predominated in the populations selected on Thatcher, the Thatcher isogenic line containing Lr3ka (TcLr3ka) and TcLr11 [...]
J D Sherman - One of the best experts on this subject based on the ideXlab platform.
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complementary epistasis involving sr12 explains adult plant resistance to stem rust in Thatcher wheat triticum aestivum l
Theoretical and Applied Genetics, 2014Co-Authors: Matthew N Rouse, L E Talbert, Davinder Singh, J D ShermanAbstract:Key message Quantitative trait loci conferring adult plant resistance to Ug99 stem rust in Thatcher wheat display complementary gene action suggesting multiple quantitative trait loci are needed for effective resistance. Abstract Adult plant resistance (APr) in wheat (Triticum aestivum l.) to stem rust, caused by Puccinia graminis f. sp. tritici (Pgt), is desirable because this resistance can be Pgt race non-specific. resistance derived from cultivar Thatcher can confer high levels of APr to the virulent Pgt race TTKSK (Ug99) when combined with stem rust resist- ance gene Sr57 (Lr34). To identify the loci conferring APr in Thatcher, we evaluated 160 rIls derived from Thatcher crossed to susceptible cultivar Mcneal for field stem rust
Walter A. Boeger - One of the best experts on this subject based on the ideXlab platform.
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ergasilus Thatcheri n sp copepoda poecilostomatoida ergasilidae from the gills of rhamdia quelen teleostei siluriformes pimelodidae from southern brazil
Journal of Parasitology, 2000Co-Authors: Kerlen B Engers, Deodoro A Brandao, Walter A. BoegerAbstract:The female of Ergasilus Thatcheri n. sp. (Copepoda, Poecilostomatoida, Ergasilidae) is described from the gills of the “jundia,” Rhamdia quelen (Teleostei, Siluriformes, Pimelodidae), from fish ponds in the State of Rio Grande do Sul, Brazil. The new species has a falciform semipinnate terminal seta on the first exopod, which suggests phylogenetic affinity to 10 other congeners, all from fishes of the Amazon Basin. Based on general morphology, the new species shows great similarity to E. callophysus Thatcher and Boeger, 1984, a parasite of another pimelodid fish Callophysus macropterus. Ergasilus Thatcheri n. sp., however, can be easily differentiated from E. callophysus in its possession of a more distal sensillum not located on a cuticular elevation, and a row of spinules on the inner margin of the second antennal segment (first endopodal segment).
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ergasilus Thatcheri n sp copepoda poecilostomatoida ergasilidae from the gills of rhamdia quelen teleostei siluriformes pimelodidae
2000Co-Authors: From Southern Brazil, Kerlen B Engers, Walter A. Boeger, Deodoro A BrandioAbstract:The female of Ergasilus Thatcheri n. sp. (Copepoda, Poecilostomatoida, Ergasilidae) is described from the gills of the "jundii," Rhamdia quelen (Teleostei, Siluriformes, Pimelodidae), from fish ponds in the State of Rio Grande do Sul, Brazil. The new species has a falciform semipinnate terminal seta on the first exopod, which suggests phylogenetic affinity to 10 other congeners, all from fishes of the Amazon Basin. Based on general morphology, the new species shows great similarity to E. callophysus Thatcher and Boeger, 1984, a parasite of another pimelodid fish Callophysus macropterus. Ergasilus Thatcheri n. sp., however, can be easily differentiated from E. callophysus in its possession of a more distal sensillum not located on a cuticular elevation, and a row of spinules on the inner margin of the second antennal segment (first endopodal segment). Ergasilus is the most species-rich genus of the family Er- gasilidae in South America. Twenty-one species have been de- scribed from different hosts and locations in Brazil (see Motta Amado and Rocha, 1995; Thatcher, 1998). However, the taxo- nomic status and the validity of some of these species are doubtful, probably reflecting the status of the entire genus, and a more comprehensive revision is required. During a survey of parasites of the "jundidi," Rhamdia quelen (Quoy and Gai- mard), a new species of ergasilid was collected from the gill filaments. This new species is described herein.
