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INSTITUT FÜR PFLANZENGENETIK UND KULTURPFLANZENFORSCHUNG (IPK)

Corrensstraße 3, 06466 Gatersleben, Germany.

A. Börner, O. Dobrovolskaya, E.K. Khlestkina, U. Lohwasser, S. Navakode, M.S. Roeder, V. Schubert, A. Weidner, and K. Zaynali Nezhad.

Leaf rust resistance. [p. 24]

The majority of Aegilops species is characterized by the valuable potential of resistance against economically important diseases such as powdery mildew, yellow rust, and leaf rust. The Ae. caudata accession S740-69 possesses, among others, resistance to leaf rust inherited at the seedling stage by one dominant gene and some minor factors. The C genome of Ae. triuncialis and Ae. caudata is known to cause gametocidal effects. The expression of these effects was slightly reduced in the Ae. caudata accession S740-69. Therefore, six of the seven possible monosomic addition lines could be selected from the cross of T. aestivum subsp. aestivum cv. Alcedo with Ae. caudata accession S740-69. Selfing of these lines permitted the selection of lines with 42 chromosomes and introgressions of Ae. caudata caused by the gametocidal effects of the C genome on the wheat background. By using microsatellite markers, segments of Ae. caudata chromatin in the wheat background were detected on chromosomes 2AS, 2BS, 3BL, 4AL, and 6DL. Different F3 populations from backcrosses of leaf rust-resistant introgression lines with a wheat like growth habit and Alcedo will be used to investigate the leaf rust resistance at the seedling stage and the location of responsible genes.

Drought stress. [p. 24]

In order to find QTL related to postanthesis drought tolerance in wheat two accessions, one tolerant line from Pakistan and one sensitive line from Sweden were selected as parental lines, and 143 lines of the F2 and F2:3 families derived from their cross were used for population genotyping using SSR markers and for phenotypic investigations. Based on a chemical desiccation method, drought stress was induced and the stress-tolerance index was calculated with a range from 23 to 55 %. For population genotyping, 550 primers were tested and a total of 356 polymorphic primers (65 %) were found. With these selected primers, all wheat genetic linkage groups will be covered. Finally, these linkage groups and data from field experiments will be used for QTL analysis.

Aluminum tolerance. [p. 24]

A set of 85 T. aestivum subsp. aestivum cv. Chinese Spring-Ae. tauschii introgression lines developed at IPK Gatersleben were grown in nutrient solutions and characterized at the seedling stage for tolerance to aluminum and to map the genetic loci involved. The experimental principle is based on a comparative evaluation between aluminum-stress conditions and a control with nutrient solution only. The root tolerance index (RTI = length of roots grown with Al / length of roots grown without Al*100) was calculated. Using microsatellite markers, a major QTL was mapped on the long arm of chromosome 4D near the centromere indicating the influence of the D genome on aluminum tolerance in wheat.

Preharvest sprouting / dormancy. [p. 24-25]

Two wheat mapping populations, the International Triticeae Mapping Initiative (ITMI) population and D-genome introgression lines, were evaluated for the domestication traits of preharvest sprouting and dormancy. Cultivation in the field and the greenhouse was used to discover the influence of environmental conditions on detecting QTL for these traits. No significant correlation between the evaluated traits and the environmental conditions was found. Under field conditions, major QTL could be localized for preharvest sprouting on chromosome 4AL and for dormancy on chromosome 3AL in the ITMI population. Under greenhouse conditions, a major QTL on chromosome 4AL was found for both traits. The major QTL on chromosome 3AL could not be detected again. The D-genome introgression lines were researched under greenhouse conditions at first. A major QTL for dormancy was localized on chromosome 6DL, but no QTL was found for preharvest sprouting. Under field conditions, the major QTL on chromosome 6DL could not be identified again. For preharvest sprouting, it was not possible to find an important genome region. The influence of environmental conditions could not be researched.

Duplicate identification in germ plasm collections. [p. 25]

Genebank accessions of the Gatersleben collection were selected based on the screening of the passport data for identical cultivar names or accession numbers of the donor genebanks. Twelve potential duplicate groups consisting of three to nine accessions with identical names/numbers were selected and analyzed with DNA markers (microsatellites). A bootstrap approach based on resampling of both microsatellite markers and alleles within marker loci was used to test for homogeneity. Although several homogenous groups were identified, it became clear that only cultivar name did not allow the determination of duplicates. A combination of SSR-analysis followed by the bootstrap method and database survey considering the botanical classification and other data (origin, growth habit, donor) available is necessary in order to determine duplicates.

Leaf pubescence genes. [p. 25]

A study was initiated to map genes determining hairy leaves in cultivated wheat and a wheat/Ae. speltoides introgression line. A QTL-mapping approach also was performed to investigate the ITMI mapping population and consider the hairiness of leaves and auricles. Two major genes controlling leaf pubescence were mapped on chromosomes 4BL (Hl1) and 7BS (Hl2Aesp) in the hexaploid wheat Saratovskaya 29 and a wheat/Aegilops introgression line (102/00i), respectively, together with QTL determining hairiness of leaf margin (QHl.ipk-4B, QHl.ipk-4D) and auricle (QPa.ipk-4B, QPa.ipk-4D) on the long arms of chromosomes 4B and 4D. The QTL on chromosome 4D were contributed by the synthetic wheat and, therefore, originated from Ae. tauschii. The homoeologous, group-4 wheat/Ae. tauschii genes/QTL detected in the present study line up with the barley pubescence genes Hln/Hsh and Hsb and the hairy peduncle rye gene Hp1. The locus seems to be pleiotropically responsible for the pubescence of different plant organs in different species of the Triticeae. Another homoeologous series may be present on the short arms of the homoeologous group-7 chromosomes, concluded from an allelic test cross between the Chinese local cultivar Hong-mang-mai carrying Hl2 and the wheat/Ae. speltoides introgression line 102/00'.

Glume color and pubescence. [p. 25]

Microsatellite markers were used for the precise mapping and comparative studies of the genes determining the traits red glume color (Rg3 on chromosome 1A and Rg1 on chromosome 1B), black glume color (Bg on chromosome 1A), smoky-gray glume color (on chromosome 1D), and hairy glume (Hg on chromosome 1A). The loci were mapped to the distal regions of the chromosomes 1AS, 1BS, and 1DS, respectively, between markers Xgwm1223 (in proximal or closely linked position) and Xgwm0033 (distal). From the results and from the known close linkage of these genes with homoeologous gliadin loci, we concluded that we had mapped a homoeologous series and proposed the designation Rg-A1, Rg-B1, and Rg-D1. Genes Rg3 and Bg were considered to be different alleles of the locus Rg-A1. Both Rg3 and Bg were found to be closely linked to the major glume pubescence gene Hg, also mapped in the present study. The smoky-gray glume gene and Rg2 (1D), the latter mapped previously in a synthetic wheat, were proposed to be different alleles of the locus Rg-D1.

Purple grain color. [p. 25-26]

Three genes for purple grain color, Pp1, Pp2, and Pp3 (now designated Pp1, Pp3b, and Pp3a, respectively), were mapped using crosses between the purple-grained hexaploid wheats Purple (Pp1Pp1Pp3Pp3 (Pp1Pp1Pp3aPp3a)) and Purple Feed (Pp1Pp1Pp2Pp2 (Pp1Pp1Pp3bPp3b)) with the nonpurple-grained cultivars Novosibirskaya 67 and Saratovskaya 29. The genes Pp2 (Pp3b) and Pp3 (Pp3a) were inherited as monofactorial dominant when purple grained wheats were crossed to Novosibirskaya 67. Both were mapped in the centromeric region of the chromosome 2A. Therefore, they were suggested being different alleles at the same locus and designated Pp3a and Pp3b. In the crosses between purple-grained wheats and Saratovskaya 29, a segregation ratio of 9 (purple) to 7 (nonpurple) was obtained suggesting a complementary interaction of two dominant genes, Pp1 and Pp3. To map Pp1 as a single gene, the influence of the other Pp gene was taken into consideration by determining the Pp3 genotype of the F2 plants. The gene was mapped on chromosome 7BL, about 24 cM distal to the centromere. The Pp1 gene was shown to be nonallelic to the Rc-1 (red coleoptile) and Pc (purple culm) genes, contrary to what was previously suggested. The coloration caused by the Pp genes was found to have no effect on preharvest sprouting.

Publications. [p. 26-27]

• Bálint AF, Röder MS, Hell R, Galiba G, Sutka J, and Börner A. 2006. Cereals with better heavy metal tolerance: physical and genetic mapping of copper tolerance in wheat. In: Proc 13th Internat EWAC Workshop, Prague, Czech Republic, 2005 (in press).
• Barzali M, Lohwasser U, Niedzielski M, and Börner A. 2005. Effects of different temperatures and atmospheres on seed and seedling traits in a long term storage experiment on rye (Secale cereale L.). Seed Sci Tech 33:713-721.
• Börner A, Freytag U, and Sperling U. 2005. Analysis of wheat disease resistance data originating from screenings of Gatersleben genebank accessions during 1933 and 1992. Genet Res Crop Evol DOI: 10.1007/s10722-004-1158-8.
• Börner A, Röder MS, Chebotar S, Varshney RK, and Weidner A. 2005. Molecular tools for genebank management and evaluation. In: Proc 5th Internat Triticeae Symp, Czech Journal of Genetics and Breeding 41:122-127.
• Börner A, Schäfer M, Schmidt A, Grau M, and Vorwald J. 2005. Geographical distribution of morphological characters in hexaploid wheat (Triticum aestivum L.). Plant Genet Res 3:360-372.
• Börner A, Korzun V, Khlestkina EK, Dobrovolskaya OB, Pshenichnikova TA, Castro AM, and Röder MS. 2006. Genetic stocks in the 21st century - waste or important tool? In: Proc 13th Internat EWAC Workshop, Prague, Czech Republic, 2005 (in press).
• Castro AM, Gimenez DO, Manifesto M, Tocho E, Searez G, Barragan M, Tacaliti E, Suarez E, Dobrovolskaya O, Röder MS, and Börner A. 2005. Mapping antixenosis genes to aphids on chromosome 6A of wheat. Plant Breed 124:229-233.
• Chebotar SV, Börner A, and Sivolap YM. 2006. Dwarfing genes in Ukrainian bread wheat varieties. Cytol Genet (in press).
• Chebotar SV, Röder MS, and Börner A. 2006. Analysis of Ukrainian wheat varieties by using diagnostic marker for Yrns-B1. In: Proc 13th Internat EWAC Workshop, Prague, Czech Republic, 2005 (in press).
• Dobrovolskaya O, Arbuzova VS, Röder MS, and Börner A. 2006. Microsatellite mapping of complementary genes for purple grain colour in bread wheat (Triticum aestivum L.). Euphytica (in press).
• Dobrovolskaya O, Saleh U, Malysheva-Otto L, Röder MS, and Börner A. 2005. Rationalising germplasm collections - a case study for wheat. Theor Appl Genet 111:1322-1329.
• Eticha F, Bekele E, Belay G, and Börner A. 2005. Phenotypic diversity in tetraploid wheats collected from Bale and Wello regions of Ethiopia. Plant Genet Res 3:35-43.
• Görlitz D, Lorenz C, and Börner A. 2005. Investigation about long distance drifts of domesticated plants drift and germination experiments deliver new knowledges about the transoceanic spread of crop plants. Migration and Diffusion 6:6-29.
• Khlestkina EK, Röder MS, Unger O, Meinel A, and Börner A. 2006. Nonspecific adult plant disease resistance against stripe rust (Puccinia striiformis) - fine mapping and origin of Yrns-B1. In: Proc 13th Internat EWAC Workshop, Prague, Czech Republic, 2005 (in press).
• Khlestkina EK, Huang X, Varshney RK, Chebotar S, Röder MS, Graner A, and Börner A. 2006. Dynamics of genetic diversity in wheat and barley germplasm collected at different time periods of last century. In: Proc 13th Internat EWAC Workshop, Prague, Czech Republic, 2005 (in press).
• Khlestkina EK, Varshney RK, Röder MS, Graner A, and Börner A. 2006. Comparative assessment of genetic diversity in cultivated barley collected at different periods of the last century in Austria, Albania and India by using genomic and genic SSR markers. Plant Genet Res (in press).
• Konarev A, Gubareva N, Kornuchin D, and Börner A. 2005. Gliadin electrophoretic analysis of the genetic integrity of wheat (Triticum aestivum L.) accessions after frequent seed reproductions. Genet Res Crop Evol 52:519-523.
• Lohwasser U, Röder MS, and Börner A. 2005. QTL mapping of the domestication traits pre-harvest sprouting and dormancy in wheat (Triticum aestivum L.). Euphytica 143:247-249.
• Lohwasser U, Röder MS, and Börner A. 2006. Influence of environmental conditions on detecting QTLs for the traits pre-harvest sprouting and dormancy in wheat (Triticum aestivum L.). In: Proc 13th Internat EWAC Workshop, Prague, Czech Republic, 2005 (in press).
• Navakode S, Varshney RK, Graner A, and Börner A. 2006. Screening OWB population for aluminium tolerance. In: Proc 13th Internat EWAC Workshop, Prague, Czech Republic, 2005 (in press).
• Navakode S, Weidner A, Varshney RK, Röder MS, and Börner A. 2006. Analysis of wheat/Ae. tauschii Coss. introgression lines for aluminium tolerance. Vorträge Pflanzenzüch (in press).
• Permyakova MD,Trufanov VA, Permyakov AV, Pshenichnikova TA, Ermakova MF, Chistyakova AK, Shchukina LV, and Börner A. 2006. Relationship between specific lipoxygenase activity and technological characteristics of gluten in the recombinant inbred lines of ITMI mapping population. In: Proc 13th Internat EWAC Workshop, Prague, Czech Republic, 2005 (in press).
• Pestsova EG, Börner A, and Röder MS. 2006. Development and QTL-assessment of Triticum aestivum - Aegilops tauschii introgression lines. Theor Appl Genet DOI: 10.1007/s00122-005-0166-1.
• Pshenichnikova TA, Börner A, Dobrovolskaya OB, Khlestkina EK, Röder M, and Ermakova MF. 2006. The use of precise genetic stocks for precise gene mapping: results obtained within EWAC. In: Proc 13th Internat EWAC Workshop, Prague, Czech Republic, 2005 (in press).
• Szira, F, Balint AF, Galiba G, Varshney RK, and Börner A. 2006. Searching for QTLs controlling drought tolerance in barley and wheat. Vorträge Pflanzenzüch (in press).
• Varshney RK, Sigmund R, Börner A, Korzun V, Stein N, Sorrells ME, Langridge P, and Graner A. 2005. Interspecific transferability and comparative mapping of barley EST-SSR markers in wheat, rye and rice. Plant Sci 168:195-202.
• Varshney RK, Prasad M, Kota R, Sigmund R, Börner A, Valkoun J, Scholz U, Stein N, and Graner A. 2005. Functional molecular markers in barley: Development and applications. In: Proc 5th Internat Triticeae Symp, Czech J Genet Breed 41:128-133.
• Weidner A, Varshney RK, Buck-Sorlin GH, Stein N, Graner A, and Börner A. 2006. QTLs for salt tolerance in three different barley mapping populations. In: Proc 13th Internat EWAC Workshop, Prague, Czech Republic, 2005 (in press).
• Zaynali Nezad K, Lohwasser U, Röder MS, and Börner A. 2006. Primary results from studies of post anthesis drought tolerance in cereals. Vorträge Pflanzenzüch (in press).