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1Latest Papers from Table of Contents or Articles in PressHaizhen A. Zhong, Elizabeth M. Santos, Chrysoula Vasileiou, Zheng Zheng, James H. Geiger, Babak Borhan and Kenneth M. Merz
American Chemical Society (ACS)
Published 2018Staff ViewPublication Date: 2018-03-06Publisher: American Chemical Society (ACS)Print ISSN: 0002-7863Electronic ISSN: 1520-5126Topics: Chemistry and PharmacologyPublished by: -
2Latest Papers from Table of Contents or Articles in PressD. Walter ; A. Lier ; A. Geiselhart ; F. B. Thalheimer ; S. Huntscha ; M. C. Sobotta ; B. Moehrle ; D. Brocks ; I. Bayindir ; P. Kaschutnig ; K. Muedder ; C. Klein ; A. Jauch ; T. Schroeder ; H. Geiger ; T. P. Dick ; T. Holland-Letz ; P. Schmezer ; S. W. Lane ; M. A. Rieger ; M. A. Essers ; D. A. Williams ; A. Trumpp ; M. D. Milsom
Nature Publishing Group (NPG)
Published 2015Staff ViewPublication Date: 2015-02-25Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsKeywords: Animals ; Bone Marrow/pathology ; *Cell Cycle ; Cell Death ; Cell Proliferation ; *DNA Damage ; Fanconi Anemia/metabolism ; Hematopoietic Stem Cells/*cytology/*metabolism ; Mice ; Reactive Oxygen Species/metabolism ; Stress, PhysiologicalPublished by: -
3Latest Papers from Table of Contents or Articles in PressThaiss, C. A., Levy, M., Grosheva, I., Zheng, D., Soffer, E., Blacher, E., Braverman, S., Tengeler, A. C., Barak, O., Elazar, M., Ben-Zeev, R., Lehavi-Regev, D., Katz, M. N., Pevsner-Fischer, M., Gertler, A., Halpern, Z., Harmelin, A., Aamar, S., Serradas, P., Grosfeld, A., Shapiro, H., Geiger, B., Elinav, E.
American Association for the Advancement of Science (AAAS)
Published 2018Staff ViewPublication Date: 2018-03-23Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyGeosciencesComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: Immunology, PhysiologyPublished by: -
4Latest Papers from Table of Contents or Articles in PressK. Howe ; M. D. Clark ; C. F. Torroja ; J. Torrance ; C. Berthelot ; M. Muffato ; J. E. Collins ; S. Humphray ; K. McLaren ; L. Matthews ; S. McLaren ; I. Sealy ; M. Caccamo ; C. Churcher ; C. Scott ; J. C. Barrett ; R. Koch ; G. J. Rauch ; S. White ; W. Chow ; B. Kilian ; L. T. Quintais ; J. A. Guerra-Assuncao ; Y. Zhou ; Y. Gu ; J. Yen ; J. H. Vogel ; T. Eyre ; S. Redmond ; R. Banerjee ; J. Chi ; B. Fu ; E. Langley ; S. F. Maguire ; G. K. Laird ; D. Lloyd ; E. Kenyon ; S. Donaldson ; H. Sehra ; J. Almeida-King ; J. Loveland ; S. Trevanion ; M. Jones ; M. Quail ; D. Willey ; A. Hunt ; J. Burton ; S. Sims ; K. McLay ; B. Plumb ; J. Davis ; C. Clee ; K. Oliver ; R. Clark ; C. Riddle ; D. Elliot ; G. Threadgold ; G. Harden ; D. Ware ; S. Begum ; B. Mortimore ; G. Kerry ; P. Heath ; B. Phillimore ; A. Tracey ; N. Corby ; M. Dunn ; C. Johnson ; J. Wood ; S. Clark ; S. Pelan ; G. Griffiths ; M. Smith ; R. Glithero ; P. Howden ; N. Barker ; C. Lloyd ; C. Stevens ; J. Harley ; K. Holt ; G. Panagiotidis ; J. Lovell ; H. Beasley ; C. Henderson ; D. Gordon ; K. Auger ; D. Wright ; J. Collins ; C. Raisen ; L. Dyer ; K. Leung ; L. Robertson ; K. Ambridge ; D. Leongamornlert ; S. McGuire ; R. Gilderthorp ; C. Griffiths ; D. Manthravadi ; S. Nichol ; G. Barker ; S. Whitehead ; M. Kay ; J. Brown ; C. Murnane ; E. Gray ; M. Humphries ; N. Sycamore ; D. Barker ; D. Saunders ; J. Wallis ; A. Babbage ; S. Hammond ; M. Mashreghi-Mohammadi ; L. Barr ; S. Martin ; P. Wray ; A. Ellington ; N. Matthews ; M. Ellwood ; R. Woodmansey ; G. Clark ; J. Cooper ; A. Tromans ; D. Grafham ; C. Skuce ; R. Pandian ; R. Andrews ; E. Harrison ; A. Kimberley ; J. Garnett ; N. Fosker ; R. Hall ; P. Garner ; D. Kelly ; C. Bird ; S. Palmer ; I. Gehring ; A. Berger ; C. M. Dooley ; Z. Ersan-Urun ; C. Eser ; H. Geiger ; M. Geisler ; L. Karotki ; A. Kirn ; J. Konantz ; M. Konantz ; M. Oberlander ; S. Rudolph-Geiger ; M. Teucke ; C. Lanz ; G. Raddatz ; K. Osoegawa ; B. Zhu ; A. Rapp ; S. Widaa ; C. Langford ; F. Yang ; S. C. Schuster ; N. P. Carter ; J. Harrow ; Z. Ning ; J. Herrero ; S. M. Searle ; A. Enright ; R. Geisler ; R. H. Plasterk ; C. Lee ; M. Westerfield ; P. J. de Jong ; L. I. Zon ; J. H. Postlethwait ; C. Nusslein-Volhard ; T. J. Hubbard ; H. Roest Crollius ; J. Rogers ; D. L. Stemple
Nature Publishing Group (NPG)
Published 2013Staff ViewPublication Date: 2013-04-19Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsKeywords: Animals ; Chromosomes/genetics ; Conserved Sequence/*genetics ; Evolution, Molecular ; Female ; Genes/genetics ; Genome/*genetics ; Genome, Human/genetics ; Genomics ; Humans ; Male ; Meiosis/genetics ; Molecular Sequence Annotation ; Pseudogenes/genetics ; Reference Standards ; Sex Determination Processes/genetics ; Zebrafish/*genetics ; Zebrafish Proteins/geneticsPublished by: -
5Latest Papers from Table of Contents or Articles in PressM. C. Florian ; K. J. Nattamai ; K. Dorr ; G. Marka ; B. Uberle ; V. Vas ; C. Eckl ; I. Andra ; M. Schiemann ; R. A. Oostendorp ; K. Scharffetter-Kochanek ; H. A. Kestler ; Y. Zheng ; H. Geiger
Nature Publishing Group (NPG)
Published 2013Staff ViewPublication Date: 2013-10-22Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsKeywords: Animals ; *Cell Aging ; Cell Differentiation ; Cell Polarity ; Female ; Haploinsufficiency ; Hematopoietic Stem Cells/*cytology ; Male ; Mice ; Mice, Inbred C57BL ; Phenotype ; Rejuvenation ; Wnt Proteins/deficiency/genetics/metabolism ; *Wnt Signaling Pathway ; cdc42 GTP-Binding Protein/metabolismPublished by: -
6Latest Papers from Table of Contents or Articles in PressW. Wang ; Z. Nossoni ; T. Berbasova ; C. T. Watson ; I. Yapici ; K. S. Lee ; C. Vasileiou ; J. H. Geiger ; B. Borhan
American Association for the Advancement of Science (AAAS)
Published 2012Staff ViewPublication Date: 2012-12-12Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: Absorption ; Electrons ; Humans ; Mutagenesis ; Point Mutation ; Retinaldehyde/*analogs & derivatives/chemistry ; Retinol-Binding Proteins, Cellular/*chemistry/genetics ; Static ElectricityPublished by: -
7Latest Papers from Table of Contents or Articles in PressLeins, H., Mulaw, M., Eiwen, K., Sakk, V., Liang, Y., Denkinger, M., Geiger, H., Schirmbeck, R.
American Society of Hematology (ASH)
Published 2018Staff ViewPublication Date: 2018-08-10Publisher: American Society of Hematology (ASH)Print ISSN: 0006-4971Electronic ISSN: 1528-0020Topics: BiologyMedicineKeywords: Hematopoiesis and Stem Cells, Immunobiology and ImmunotherapyPublished by: -
8Articles: DFG German National LicensesPresterl, T. ; Groh, S. ; Landbeck, M. ; Seitz, G. ; Schmidt, W. ; Geiger, H. H.
Oxford, UK : Blackwell Publishing Ltd
Published 2002Staff ViewISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: Maize varieties with improved nitrogen(N)-use efficiency under low soil N conditions can contribute to sustainable agriculture. Tests were carried to see whether selection of European elite lines at low and high N supply would result in hybrids with differential adaptation to these contrasting N conditions. The objective was to analyze whether genotypic differences in N uptake and N-utilization efficiency existed in this material and to what extent these factors contributed to adaptation to low N supply. Twenty-four hybrids developed at low N supply (L × L) were compared with 25 hybrids developed at high N supply (H × H). The N uptake was determined as total above-ground N in whole plants, and N-utilization efficiency as the ratio between grain yield and N uptake in yield trials at four locations and at three N levels each. Highly significant variations as a result of hybrids and hybrids × N-level interaction were observed for grain yield as well as for N uptake and N-utilization efficiency in both hybrid types. Average yields of the L × L hybrids were higher than those of the H × H hybrids by 11.5% at low N supply and 5.4% at medium N level. There was no significant yield difference between the two hybrid types at high N supply. The L × L hybrids showed significantly higher N uptake at the low (12%) and medium (6%) N levels than the H × H hybrids. In contrast, no differences in N-utilization efficiency were observed between the hybrid types. These results indicate that adaptation of hybrids from European elite breeding material to conditions with reduced nitrogen input was possible and was mainly the result of an increase in N-uptake efficiency.Type of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesButrón, A. ; Malvar, R. A. ; Revilla, P. ; Soengas, P. ; Ordás, A. ; Geiger, H. H.
Oxford, UK : Blackwell Publishing Ltd
Published 2002Staff ViewISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: The main pest of maize in north-western Spain is the pink stem borer, Sesamia nonagrioides, and stem lodging is one of the consequences of attack. Since rind puncture resistance is related to stem lodging resistance, the objectives of this work were to estimate the genetic effects involved in the inheritance of rind puncture resistance and to determine the phenotypic correlation coefficients between rind puncture resistance and pink stem borer damage. Six generations from the crosses ‘CM109’בEP31’ and ‘CM109’בEP42’ and a 10-inbred line diallel were evaluated in Pontevedra, Spain, in 1995 and 1996. The inheritance of rind puncture resistance had two significant components, one additive and one dominant. Non-allelic and genotype × environment interactions were not significant. Improvement for internode rind puncture resistance to increase stem strength and stalk lodging resistance could have some positive influence on resistance to pink stem borer. However, its use as an estimator of pink stem borer resistance cannot be generalized and so must be restricted to programmes that involve materials exhibiting physical resistance to pink stem borer attack.Type of Medium: Electronic ResourceURL: -
10Articles: DFG German National LicensesMiedaner, T. ; Gey, A.-K. M. ; Sperling, U. ; Geiger, H. H.
Oxford, UK : Blackwell Publishing Ltd
Published 2002Staff ViewISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: Leaf rust is the most frequent leaf disease of winter rye in Germany. All widely grown population and hybrid varieties are susceptible. This study was undertaken to estimate quantitative-genetic parameters of leaf-rust resistance in self-fertile breeding materials with introgressed foreign leaf-rust resistances and to analyze the relative importance of seedling and adult-plant resistance. Forty-four inbred lines and their corresponding testcrosses with a highly susceptible tester line were grown in a field in four different environments (location-year combinations) with artificial inoculation. Plots were separated by a nonhost to promote autoinfections and minimize interplot interference. Leaf-rust severity was rated on three leaf insertions at three dates. The testcrosses showed a considerably higher disease severity than the lines. High correlations (r ≅ 0.9, P = 0.01) existed among the leaf insertions and the rating dates. Large genotypic variation for resistance was found in both the inbred and testcross populations. Genotype-environment interaction and error variances were of minor importance, thus high entry-mean heritabilities were achieved. A tight correlation between the inbreds and their corresponding testcrosses was found (r = 0.88, P = 0.01). Heterosis for resistance was significant (P = 0.05), but not very important. In a seedling test with 20—30 single-pustule isolates, 34 out of 44 inbreds reacted race-specifically. From the remaining inbred lines, three were medium and seven highly susceptible. In a further greenhouse test with 16 inbreds, seven were susceptible and five were resistant in both seedling and adult-plant stages. The remaining four lines had adult-plant resistance. In conclusion, race-specific leaf-rust resistance can be selected among inbred lines per se. Lines should also be tested in the adult-plant stage.Type of Medium: Electronic ResourceURL: -
11Articles: DFG German National LicensesMelchinger, A. E. ; Geiger, H. H. ; Seitz, G. ; Schmidt, G. A.
Oxford, UK : Blackwell Publishing Ltd
Published 1987Staff ViewISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: The importance of epistasis for forage performance and quality traits was studied in early maturing European maize (Zea mays L.) breeding materials. Sixty-six three-way crosses (3W), 33 of the flint x (dent · dent) and 33 of the dem × (flint · flint) type, were compared with the mean of their respective non-parental single crosses (〈inlineGraphic alt="inline image" href="urn:x-wiley:01799541:PBR185:PBR_185_mu1" location="equation/PBR_185_mu1.gif" extraInfo="missing"/〉) using data obtained in six environments. For each of the 11 traits examined, at least 6 out of the 66 three-way crosses displayed significant (P 〈 0.05) epistatic deviations, calculated as 〈inlineGraphic alt="inline image" href="urn:x-wiley:01799541:PBR185:PBR_185_mu1" location="equation/PBR_185_mu1.gif" extraInfo="missing"/〉– 3W. Averaged over crosses and environments, epistatic deviations were highly significant (P 〈 0,31] for 8 trails, but of minor importance except for grain yield. In general, the variance of epistatie deviations was appreciably smaller than the variance of genotype × environment interactions. Highly significant correlations occurred among epistatie deviations for silking date, dry matter content of ear, and dry matter yield of grain and stover. The reliability of predicting the performance of three-way crosses from 2W as opposed to assessing them directly was investigated as a function of the number of test environments. Disturbing e fleets of epistasis on prediction only became important under intense testing (〉 3 or 4 environments), With fewer test environments, both procedures were almost equivalent, due to a smaller influence of genotype × environment interaction on the 〈inlineGraphic alt="inline image" href="urn:x-wiley:01799541:PBR185:PBR_185_mu1" location="equation/PBR_185_mu1.gif" extraInfo="missing"/〉 values, Epistasis is concluded to be of minor importance with regard to the optimum type of hybrid for forage use.Type of Medium: Electronic ResourceURL: -
12Articles: DFG German National LicensesMelchinger, A. E. ; Schmidt, G. A. ; Geiger, H. H.
Oxford, UK : Blackwell Publishing Ltd
Published 1986Staff ViewISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: The prediction of grain and stover quality parameters in maize {Zea mays L.) by near infra-red reflectance spectroscopy (NIRS) was studied. A total of 110 grain and 135 stover samples originating from different genotypes and environments were assayed. Calibration equations for content of crude protein (CP), crude fat (CF), starch (ST), and water soluble carbohydrates (WSC) in grain were obtained by multiple linear regression of known manual values on NIRS data from the odd numbered samples. Calibrations for CP, acid detergent fibre (ADF), in vitro digestible organic matter according to the Tilley & Terry (IVDOM-T & T) and the gas production (IVDOM-Gp) method, respectively, and metabolizable energy (ME) in stover were developed analogously. Equations were validated with the evennumbered .samples and for ME additionally with the 1584 stover samples from an experiment with 66 F1 hybrids tested in six environments. The coefficients of multiple determination (R2) of the prediction equations ranged from 0.80 for IVDOM-Gp and ME in stover to 0.94 for CP in grain. Standard errors of calibration (SEC) and prediction (SEP) were in most cases not higher than commonly reported for conventional manual assays. With regard to the correct ranking of hybrids, prediction equations for ME applied well to stover samples from other environments with one exception. We concluded that NIRS can evaluate the quality traits investigated to a similar degree to that of conventional methods of analysis. Since NIRS is simple and safe to operate and allows rapid screening of several quality traits simultaneously, it should be particularly attractive for breeding purposes.Type of Medium: Electronic ResourceURL: -
13Articles: DFG German National LicensesPodlich, D. W. ; Cooper, M. ; Basford, K. E. ; Geiger, H. H.
Oxford, UK : Blackwell Publishing Ltd
Published 1999Staff ViewISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: Multi-environment trials (METs) are used in plant breeding programmes to evaluate genotypes (lines/families) as a basis for selection on expected performance (yield and/or quality) in a target population of environments (TPE). When a large component of the genotype environment (G × E) interactions results from crossover interactions, samples of environments in METs that deviate from the TPE provide a suboptimal basis for selection of genotypes on performance expected in the TPE. To adjust for the negative effects of these deviations, a selection strategy that weights the data from the MET according to their expected frequency of occurrence in the TPE (i.e. a weighted selection strategy) was investigated. Computer simulation methodology was used to obtain preliminary information on the weighted selection strategy and compare it to the traditional unweighted selection strategy for a range of MET scenarios and G × E interaction models. The evaluation of the weighted selection strategy was conducted in context with the germplasm enhancement programme (GEP) of the Northern Wheat Improvement Programme in Australia. The results indicated that when the environments sampled in the MET matched those expected in the TPE, the unweighted and weighted selection strategies achieved a similar response to selection in the TPE. However, when the environments sampled in the MET did not match the expectations in the TPE and a large component of the G × E interactions resulted from crossover interactions, the weighted selection strategy achieved a greater response to selection in the TPE. The advantage of the weighted strategy increased as the amount of crossover G × E interaction increased or fewer environments were sampled in the METs.Type of Medium: Electronic ResourceURL: -
14Articles: DFG German National LicensesStaff View
ISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: The amount of genetic variation among inbred lines and testcrosses, and covariation between both genetic materials, are of crucial importance for selection efficiency in hybrid breeding. To estimate these quantitative genetic parameters for resistance of winter rye (Secale cereale) to head blight caused by Fusarium culmorum, 88 three-way cross hybrids, produced by crossing each of 44 S2 Carsten inbred lines with two unrelated Petkus single-cross testers, were evaluated along with the parental lines over 2 years. Resistance traits were head-blight rating and grain weight per spike relative to the non-inoculated control. Significant genotypic variation occurred among lines and in both testcross series. S2 lines displayed considerably more variation than testcross series. Genotype × environment interaction was more marked among the inbred lines, while estimates of heritability were similar for both genetic materials. Testcrosses showed heterosis for head-blight resistance. No relationship existed between S2 lines and the two testcross series for any resistance trait. This might be caused by an association between inbreeding and Fusarium-head-blight susceptibility and different inbreeding depression among the S2 population. The phenotypic correlations between the testcross series were moderate for both traits (r = 0.58, P 〈 0.01). In conclusion, Fusarium-head-blight resistance has to be selected at the respective heterozygosity levels.Type of Medium: Electronic ResourceURL: -
15Articles: DFG German National LicensesHöxter, Henriette ; Sieber, Gerlinde ; Miedaner, T. ; Geiger, H. H.
Oxford, UK : Blackwell Publishing Ltd
Published 1992Staff ViewISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: The first results of three test systems for evaluating the susceptibility of rye inbred lines to foot rot caused by Fusarium culmorum and F. graminearum are presented. The test systems were specifically designed for greenhouse, foliar tent and field experiments. The inbred lines, some of which are being used in commercial hybrids, showed significant variation for resistance. Significant interactions occurred between genotypes and test systems, and within the test systems between genotypes and years or growth stages. A significant correlation existed between susceptibility in the greenhouse and in the field (r = 0.84, P = 0.05), when inoculation in the greenhouse took place at the jointing stage (EC 31). In earlier growth stages, however, this correlation was not significant. In both greenhouse and foliar tent experiments, susceptibility to F. culmorum and F. graminearum was strongly correlated (r = 0.71, 0.87, resp., P = 0.01). In the field, F. culmorum alone was used for artificial inoculation. Genotypic variance and repeatability in the field were highest after inoculation in spring with conidia suspensions. It is concluded that, in inbreeding generations with limited seed quantities, the greenhouse and the foliar-tent test systems offer good possibilities of indirectly improving foot-rot resistance in rye.Type of Medium: Electronic ResourceURL: -
16Articles: DFG German National LicensesStaff View
ISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: The quantitative-genetic basis of sprouting resistance in winter rye (Secale cereale L.) was investigated in order to facilitate breeding for improved baking quality. Crosses within and between the Petkus and Carsten gene pools were tested along with the parental lines over two locations, two years, and two harvest dates. Heritabilities of approximately 0.6 were found for falling number (FN), a-amylase activity, dormancy, and amylograph curve characters. FN showed moderate heterosis that reached 35%. High genetic variation for FN was observed in most genetic materials, and error variances were generally small. Considerable genotype × year interactions occurred. Genotypes with high FN showed more instability for FN over environments. General combining ability was the main source of genetic variation for FN (80%) and was correlated with line per se performance in the Carsten gene pool (r = 0.66). FN showed moderate to strong correlations with slowness of development, but only loose ones or none with other agronomic traits. We conclude that improving sprouting resistance by selecting for FN should be highly effective and would not cause unfavourable side effects with regard to yielding performance.Type of Medium: Electronic ResourceURL: -
17Articles: DFG German National LicensesAbdel-Ghani, A. H. ; Parzies, H. K. ; Ceccarelli, S. ; Grando, S. ; Geiger, H. H. ; Graner, A.
Oxford, UK : Blackwell Publishing Ltd
Published 2003Staff ViewISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: Previous studies have revealed that, in areas affected by severe drought, yielding ability and stability of barley (Hordeum vulgare L.) could be improved by increasing the level of heterozygosity. One possible approach to increase the heterozygosity level is to improve the outcrossing rate. In view of that, the genetic variability and phenotypic correlation coefficients involving four floral traits related to outcrossing behaviour were investigated in 274 drought adapted barley lines from the International Center for Agricultural Research in the Dry Areas (ICARDA's) current breeding programme. A significant quantitative variation existed in anther length and width, stigma length, and anther extrusion, which indicate that selection for these traits may be effective. Anther extrusion showed weak but highly significant positive correlations with anther and stigma length. Somewhat higher positive correlations were found between anther and stigma length. The results indicate that selection for high anther extrusion and longer anthers and stigmata may increase outcrossing in cultivated barley and consequently improve yielding ability through enhanced heterozygosity.Type of Medium: Electronic ResourceURL: -
18Articles: DFG German National LicensesStaff View
ISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: In maize, inbred lines are used for the production of hybrid varieties. Corn breeders and researchers have considered using haploids to develop inbred lines; however, this procedure has not been practically applied because of the inefficiency of chromosome doubling of maize haploid seedlings. In this report, a procedure has been developed to overcome this difficulty. Maize haploid seedlings obtained from eight different genotypes were treated with nitrous oxide gas (2 days at 600 kPa). Treatment at the six-leaf stage (flower primordia formation stage) significantly increased the occurrence of fertile sectors on both tassels and ears so that approximately half (44%) of the treated haploids produced kernels after self-pollination. In the control, only 11% of haploids produced selfed kernels owing to spontaneous chromosome doubling. A strong genotypic effect on the occurrence of fertile sectors after the treatment was observed. This procedure can be used for inbred line development in maize breeding programmes.Type of Medium: Electronic ResourceURL: -
19Articles: DFG German National LicensesStaff View
ISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: Turcicum or northern corn leaf blight (NCLB) incited by the ascomycete Setosphaeria turcica, anamorph Exserohilum turcicum, is a ubiquitous foliar disease of maize. Diverse sources of qualitative and quantitative resistance are available but qualitative resistances (Ht genes) are often unstable. In the tropics especially, they are either overcome by new virulent races or they suffer from climatically sensitive expression. Quantitative resistance is expressed independently of the physical environment and has never succumbed to S. turcica pathotypes in the field. This review emphasizes the identification and mapping of genes related to quantitative NCLB resistance. We deal with the consistency of the genomic positions of quantitative trait loci (QTL) controlling resistance across different maize populations, and with the clustering of genes for resistance to S. turcica and other fungal pathogens or insect pests in the maize genome. Implications from these findings for further genomic research and resistance breeding are drawn.Incubation period (IP) and area under the disease progress curve (AUDPC), based on multiple disease ratings, are important component traits of quantitative NCLB resistance. They are generally tightly correlated (rp≅ 0.8) and highly heritable (h2≅ 0.75). QTL for resistance to NCLB (IP and AUDPC) were identified and characterized in three mapping populations (A, B, C). Population A, a set of 121-150 F3 families of the cross B52×mo17, represented US Corn Belt germplasm with a moderate level of resistance. It was field-tested in Iowa, USA, and Kenya, and genotyped at 112 restriction fragment length polymorphism (RFLP) loci. Population B consisted of 194-256 F3 families of the cross Lo951×CML202, the first parent being a Corn-Belt-derived European inbred line and the second parent being a highly resistant tropical African inbred line. The population was also tested in Kenya and genotyped with 110 RFLP markers. Population C was derived from a cross between two early-maturing European inbred lines, D32 and D145, both having a moderate level of resistance. A total of 220 F3 families were tested in Switzerland and characterized with 87 RFLP and seven SSR markers. In each of the three studies, 12-13 QTL were detected by composite interval mapping at a signifcance threshold of LOD=2.5. The phenotypic and the genotypic variance were explained to an extent of 50-70% and 60-80%, respectively. Gene action was additive to partly dominant, as in previous generation means and combining ability analyses with other genetic material. In each population, gene effects of the QTL were of similar magnitude and no putative major genes were discovered. QTL for AUDPC were located on chromosomes 1 to 9. All three populations carried QTL in identical genomic regions on chromosomes 3 (bin 3.06/07), 5 (bin 3.06/07) and 8 (bin 8.05/06). The major genes Ht2 and Htn1 were also mapped to bins 8.05 and 8.06, suggesting the presence of a cluster of closely linked major and minor genes. The chromosomal bins 3.05, 5.04 and 8.05, or adjacent intervals, were further associated with QTL and major genes for resistance to eight other fungal diseases and insect pests of maize. Bins 1.05/07 and 9.05 were found to carry population-specifc genes for resistance to S. turcica and other organisms. Several disease lesion mimic mutations, resistance gene analogues and genes encoding pathogenesis-related proteins were mapped to regions harbouring NCLB resistance QTL.Type of Medium: Electronic ResourceURL: -
20Articles: DFG German National LicensesBoppenmaier, J. ; Melchinger, A. E. ; Seiltz, G. ; Geiger, H. H. ; Herrmann, R. G.
Oxford, UK : Blackwell Publishing Ltd
Published 1993Staff ViewISSN: 1439-0523Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionNotes: Restriction fragment length polymorphisms (RFLPs) have been proposed for predicting the yield potential of different types of cross. Their has been evaluated in 15 flint and 12 dent inbreds from the European maize (Zea mays L.) germplasm as well as in 68 F1 crosses (21 flint × flint, 14 dent × dent, and 33 flint × dent) produced between them. The materials were evaluated for F1 performance and midparent heterosis of grain yield, dry matter content (DMC) and plant height in two environments in Germany. Genetic distances (GDs) between parental lines, calculated from RFLP data of 194 clone-enzyme combinations, showed greater means for flint × dent (0.67) than dent × dent (0.62) and flint × flint (0.55) crosses. Cluster analysis based on GDs resulted in a clear separation of flint and dent lines and agreed well with pedigree information. For the complete set of 64 crosses analyzed (excluding 4 crosses between closely related lines) correlations of GD with F1 performance and heterosis were significant for all traits except F1 performance of DMC. When separate calculations were performed for individual subjets of crosses, correlations of GD with Fl performance and heterosis were significantly positive (0.48 ≤ r ≤ 0.80) for all traits in the flint × flint crosses, but not significant for the subsets of flint × dent and dent × dent crosses. Our results confirm those of previous investigations in that the predictive value of RFLP data is restricted to crosses between lines from the same heterotic group, and cannot be applied to crosses between lines from genetically divergent heterotic groups.Type of Medium: Electronic ResourceURL: