* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download molecular marker-based characterization of barley powdery mildew
Population genetics wikipedia , lookup
Public health genomics wikipedia , lookup
Nutriepigenomics wikipedia , lookup
Deoxyribozyme wikipedia , lookup
Genetically modified organism containment and escape wikipedia , lookup
Genetic engineering wikipedia , lookup
Site-specific recombinase technology wikipedia , lookup
SNP genotyping wikipedia , lookup
Epigenetics of neurodegenerative diseases wikipedia , lookup
No-SCAR (Scarless Cas9 Assisted Recombineering) Genome Editing wikipedia , lookup
Quantitative trait locus wikipedia , lookup
Designer baby wikipedia , lookup
Therapeutic gene modulation wikipedia , lookup
Point mutation wikipedia , lookup
Selective breeding wikipedia , lookup
Helitron (biology) wikipedia , lookup
Genetically modified crops wikipedia , lookup
History of genetic engineering wikipedia , lookup
Dominance (genetics) wikipedia , lookup
______AGRONOMIJAS VĒSTIS (Latvian Journal of Agronomy), No.11, LLU, 2008____ exhibited the highest direct effect on seed yield both in dry and rainy growing seasons. Therefore, both these traits seem to be good selection criteria to improve sunflower seed yield. References 1. Fehr W. R. (1993) Principles of cultivar development. V.1. Macmillan Publ. New York, USA, 536. 2. Göksoy A. T. and Turan Z. M.. (2007) Correlations and path analysis of yield components in synthetic varieties of sunflower (H annuus L.) Acta Agron. Hungarica, 55:3, 339-345. 3. Kaya, Y. and Atakisi. I. K. (2003). Path and correlation analysis in different yield characters in sunflower (Helianthus annuus L.). Anadolu Journal.13. 31-45. 4. Kaya Y., G. Evci, V. Pekcan ve T Gucer. (2003) Ayciceginde Tane ve Yag Veriminin Olusumunda Etkili Verim Ogelerinin Katki Oranlarının Belirlenmesi. Turkiye 5. Tarla Bitkileri Kongresi. 13-17 Ekim 2003, Diyarbakir. 120-125. 5. Miller J.F. and Fick G.N. (1997) Sunflower Genetics. In: A.A. Schneiter (ed.) Sunflower Technology and Production. Agron. Monogr. 35. Madison, WI, USA, 441-495. 6. Ozcan K. ve Acikgoz, N. (1999). Populasyon Genetigi icin bir Istatistik Paket Programı Gelistirilmesi. 3. Tarimda Bilgisayar Uygulamalari Sempozyumu, 3 - 6 Ekim, Adana, 160-165. 7. Singh R. K. and Chaudhary B. D. (1979) Biometrical Methods in Quantitative Genetic Analysis. 2nd Edition. Kalyani Publishers. New Delhi, India. 304. 8. Vidhyavathi R., Mahalakshmi P., Manivannan N., Murulidharan V. (2005). Correlation and path analysis in sunflower (H. annuus L.). Agricultural Sci. Digest, 25, 16-10. SAULESPUĖU (Helianthus annuus L) RAŽAS PAZĪMJU KORELĀCIJU ANALĪZE Kaya Y., Evci G., Pekcan V., Gucer T., Durak S., Yilmaz M.I. Saulespuėu selekcionāriem jāzina, ka pazīmes, kuras galvenokārt nosaka sēklu ražu, ir kvantitatīvas un tās ietekmē vide, kā arī vides un pazīmes mijiedarbība. Korelācijas koeficientu analīze palīdz selekcionāram izskaidrot tiešās un netiešās ietekmes, tādejādi šī metode plaši tiek izmantota selekcijas darbā. Pētījums veikts, izmantojot ražas datus un korelāciju analīzes Nacionālā Saulespuėu pētījumu projekta izmēăinājumā iekĜautajiem hibrīdiem. Projekts notiek Edirne provincē, kurā ražo 20 % no Turcijas saulespuėu produkcijas. Kopumā 2932 saulespuėu hibrīdi tika pētīti 118 izmēăinājumos šī pētījuma gaitā. Augstražīgu hibrīdu selekcijā pazīmei - 1000 graudu svars - bija būtiskākā nozīme. Ziedkopas diametrs un auga garums gan sausos, gan lietainos augšanas apstākĜos bija nākamie nozīmīgākie, balstoties uz vienkāršām korelācijas analīzēm. MOLECULAR MARKER-BASED CHARACTERIZATION OF BARLEY POWDERY MILDEW MLO RESISTANCE LOCUS IN EUROPEAN VARIETIES AND BREEDING LINES 1 Kokina A.1, LegzdiĦa L.2, BērziĦa I.2, Bleidere M.3, Rashal I.4 and Rostoks N. 1 Faculty of Biology, University of Latvia, 4 Kronvalda Blvd., Rīga, LV-1586, Latvia , phone: +371 6703 4867, e-mail: [email protected] 2 State Priekuli Plant Breeding Institute, Zinatnes str. 1a, Priekuli, Latvia 3 State Stende Cereal Breeding Institute, Dižstende, Talsu raj., Latvia 4 Institute of Biology, University of Latvia, Miera str. 3, Salaspils, LV-2169, Latvia Abstract Powdery mildew is an economically important barley disease, caused by a fungal pathogen Blumeria (Erysiphe) graminis f.sp. hordei. While the pathogen is relatively easily controlled by fungicides, it may represent a serious threat for barley produced in low input and organic agriculture. Alternatively, the disease can be controlled using resistance genes that are either specific for certain fungal pathotypes or confer resistance to a broad range of pathotypes. Naturally occurring and induced recessive mutations in the Mlo gene provide race nonspecific resistance that has been effective against almost all powdery mildew pathotypes. The Mlo gene has been cloned and several resistance allele have been characterized at the DNA sequence level. Here we report the 77 ______AGRONOMIJAS VĒSTIS (Latvian Journal of Agronomy), No.11, LLU, 2008____ identification of a novel mlo allele in a mutant in the cultivar Maja, which represents an amino acid Gly318 to Arg exchange. Available CAPS (Cleaved Amplified Polymorphic Sequence) and indel markers for mlo-5, mlo-9 and mlo-11 alleles were used to screen a selection of European barley varieties, as well as Latvian and foreign breeding lines for the presence of mlo resistance. The results of our study demonstrate the advantages of using molecular markers for the selection of mildew resistant hybrids. Key words: barley, molecular marker, Mlo gene, Cleaved Amplified Polymorphic Sequences, CAPS, indel Introduction The barley crop was the fourth largest in the world by production in 2005 (FAO, http://www.fao.org ) with the end uses being mostly food, feed and malt production. The most important factors affecting barley production are abiotic stresses, such as drought, cold and soil salinity (Stanca, 2003), as well as biotic stresses, such as fungal pathogens (Weibull et al., 2003). The control of pathogens is usually achieved by the application of fungicides during the growing season, but such practice has associated cost penalties as well as often unpredictable effects on wildlife biodiversity. Moreover, the use of pesticides is unacceptable in organic agriculture. The combination of these factores requires the development of barley varieties that combine high yield and defined quality parameters with natural disease resistance. In barley, specific powdery mildew resistance is conferred by several loci of which the Mla locus is probably the best studied and the most important. The complex Mla locus is located on the short arm of the barley chromosome 1H and consists of several NBS-LRR type disease resistance genes providing resistance to different fungal pathotypes (Wei et al., 1999). The locus has been completely sequenced from the susceptible cultivar Morex and the resistance alleles Mla1 (Zhou et al., 2001), Mla6 (Halterman et al., 2001), Mla12 (Shen et al., 2003) and Mla13 (Halterman et al., 2003) have been characterized (Mejlhede et al., 2006). However, gene-for-gene disease resistance provided by Mla genes is relatively rapidly overcome by the evolution of pathogen avirulence factors (Weibull et al., 2003), thus, race nonspecific resistance genes are desirable. Naturally occurring and induced recessive mutations at the Mlo locus on the barley chromosome 4H confer race nonspecific resistance against most of the powdery mildew pathotypes (Jørgensen, 1992). The Mlo gene has been cloned, multiple resistance alleles have been characterized at the DNA sequence level and molecular markers are available for marker-assisted selection (Buschges et al., 1997; Piffanelli et al., 2004). mlo-mediated resistance comes with a yield penalty because of the necrotic lesions on plant leaves (Wolter et al., 1993), therefore mlo-11 allele is often used in plant breeding as it exhibits a residual production of a functional MLO protein (Piffanelli et al., 2004). However, many varieties also possess the mlo-5 and mlo-9 alleles resulting from single nucleotide mutations in the Mlo gene (Buschges et al., 1997). CAPS (Cleaved Amplified Polymorphic Sequences) markers are PCR-amplified DNA regions that exhibit polymorphic DNA fragments after digestion with restriction endonucleases (Konieczny and Ausubel, 1993). In case of cloned genes, the CAPS markers can be designed based on the DNA sequence targeting specific DNA polymorphisms that alter restriction sites. CAPS markers are available for mlo-5 and mlo-9 alleles since mutations destroy the EcoRV and HhaI sites, respectively (Schulze-Lefert et al., 1998). In addition to the CAPS marker, a SNaPShot assay has been reported for the mlo-9 allele (Ovesna et al., 2003). The naturally occurring mlo-11 allele is caused by a complex sequence duplication of the Mlo locus, therefore detection of the mlo-11 allele is based on the genotyping of closely linked loci (Piffanelli et al., 2004; Tacconi et al., 2006). In this study we used molecular markers to characterize resistance alleles at the Mlo locus in a selection of European barley varieties and breeding lines, and we also sequenced a novel mlo allele. Molecular markers flanking the Mlo gene and targeting the induced mutations could be used to determine the presence and segregation of mlo-5, mlo-9 and mlo-11 alleles in hybrids. 78 ______AGRONOMIJAS VĒSTIS (Latvian Journal of Agronomy), No.11, LLU, 2008____ Materials and Methods DNA from 44 European barley varieties and 15 Latvians breeding lines (Table 1) was extracted from a single barley plant using a modified procedure by (Edwards et al., 1991). Plant tissue was collected either from a field-grown plant or a seedling germinated on Petri dish in the laboratory. Seeds were obtained from the State Priekuli Plant Breeding institute and State Stende Cereal Breeding institute. DNA extractions from barley hybrid lines were performed from a combined tissue sample originating from five plants. The Mildew resistant barley mutant line 792-99 previously characterized as allelic to mlo (I. Rashal, unpublished), was obtained from the Institute of Biology, University of Latvia. A single mutant plant was used for DNA extractions and sequence analysis. PCR was performed in a 20 1 reaction consisting of ca. 50 ng DNA, 10 M primers, 1 x reaction buffer (Fermentas, Vilnius, Lithuania), 2.5 mM MgCl2, 0.2 mM dNTPs and 1 u of Hot Start Taq polymerase (Fermentas, Vilnius, Lithuania). PCR primers and conditions for mlo-11 allele are described (Piffanelli et al., 2004). Barley CAPS markers for mlo-5 and mlo-9 alleles are described (Schulze-Lefert et al., 1998), except that the primers Y14573_F02 (5’CGCCAGCAAACCAGACACAC-3’) and Y14573_R01 (5’-TTCCATGAGGACGGACACGA-3’) were used to amplify a 321 bp fragment. Digestion with enzymes HhaI and EcoR32I (Fermentas, Vilnius, Lithuania) was done according to manufacturer’s recommendations. Restriction digests were analyzed on 1.5% w/v agarose gels (Fermentas, Vilnius, Lithuania). Primers for PCR amplification and the sequencing of the Mlo coding region were from (Mejlhede et al., 2006). Sequencing was done using BigDye 3.1. terminator mix (Applied Biosystems, Foster City, CA, USA) on an ABI3730 sequencer according to the manufacturer’s recommendations. Base calling and the sequence assembly was done using the Staden software package (Staden, 1996). The sequence alignment of mutant and wild type Mlo genes was done with Clustal 1.83 software (Thompson et al., 1997). Results and Discussion CAPS markers for mlo-5 and mlo-9 alleles (Figure 1A for their location in Mlo gene) and an indel marker for the mlo-11 allele (Piffanelli et al., 2004) were used to screen a selection of European barley varieties and breeding lines (Table 1) for the presence of mlo resistance alleles. We identified one variety with the mlo-5 allele, two varieties with mlo-9 alleles and five varieties with the mlo-11 allele (Table 1) based on DNA fragment sizes in agarose gels. In addition, two Latvian breeding lines appeared to carry mlo-11. The same markers were used to screen several barley hybrid lines (Figure 1B). Homozygous mlo-9 and mlo-11 alleles were detected in several hybrid lines, however, some hybrids showed a mlo-9/Mlo and mlo-11/Mlo restriction fragment pattern (Figure 1B, lanes 2 and 9, respectively). Because each hybrid line was represented by a pool of five plants, we could not distinguish between heterozygous plants and heterogeneous pools (Figure 1B), but it was a clear indication that the line was still segregating for mlo resistance. Registered Latvian barley varieties are known to be Mlo wild type, therefore introgression of mlo alleles in locally adapted germplasm could be beneficial for traditional and organic barley growers in Latvia. Application of the mlo molecular markers (Buschges et al., 1997; Piffanelli et al., 2004; SchulzeLefert et al., 1998) for barley breeding have the potential to facilitate the identification of mlo resistant progeny in crosses, in particular in the presence of other powdery mildew resistance genes, e.g., Mla. Table 1. Molecular marker-based assessment of mlo alleles in a set of barley accessions Accession Alamo Alexis Ametist Annabell Anni Ballistu Country of origin CA DE CZ DE EE FR Length of a PCR product or restriction fragment in base pairs for each marker 1 mlo-5 Eco32I mlo-9 HhaI mlo-11 (indel 3) 321 bp 195, 77, 49 bp 470 bp 321 bp 272, 49 bp 470 bp 321 bp 195, 77, 49 bp 470 bp 321 bp 195, 77, 49 bp 470 bp 321 bp 195, 77, 49 bp 470 bp 321 bp 195, 77, 49 bp 470 bp 79 Detected allele 2 wt Mlo mlo-9 wt Mlo wt Mlo wt Mlo wt Mlo ______AGRONOMIJAS VĒSTIS (Latvian Journal of Agronomy), No.11, LLU, 2008____ Barke DE 321 bp 272, 49 bp 470 bp mlo-9 Beatrice FR 321 bp 195, 77, 49 bp 470 bp wt Mlo Dziugiai LT 321 bp 195, 77, 49 bp 470 bp wt Mlo Effendi NL 321 bp 195, 77, 49 bp 470 bp wt Mlo Emir NL 321 bp 195, 77, 49 bp 470 bp wt Mlo Fager NO 218, 103 bp 195, 77, 49 bp 470 bp mlo-5 Fibar CA 321 bp 195, 77, 49 bp 470 bp wt Mlo Fink DE 321 bp 195, 77, 49 bp 470 bp wt Mlo Fontana FR 321 bp 195, 77, 49 bp 530 bp mlo-11 Forace IT 321 bp 195, 77, 49 bp 470 bp wt Mlo Fredrikson US 321 bp 195, 77, 49 bp 470 bp wt Mlo Freedom CA 321 bp 195, 77, 49 bp 470 bp wt Mlo Golf UK 321 bp 195, 77, 49 bp 470 bp wt Mlo Hellana AT 321 bp 195, 77, 49 bp 470 bp wt Mlo Heris CZ 321 bp 195, 77, 49 bp 530 bp mlo-11 Hily SE 321 bp 195, 77, 49 bp 470 bp wt Mlo Hiproly DK 321 bp 195, 77, 49 bp 470 bp wt Mlo Hockey UK 321 bp 195, 77, 49 bp 470 bp wt Mlo Ivana FI 321 bp 195, 77, 49 bp 470 bp wt Mlo Jaspis CZ 321 bp 195, 77, 49 bp 470 bp wt Mlo Jet ET 321 bp 195, 77, 49 bp 470 bp wt Mlo Justina DE 321 bp 195, 77, 49 bp 530 bp mlo-11 Karat CZ 321 bp 195, 77, 49 bp 470 bp wt Mlo Keti DK 321 bp 195, 77, 49 bp 470 bp wt Mlo Klaxon UK 321 bp 195, 77, 49 bp 470 bp wt Mlo Kompakt SK 321 bp 195, 77, 49 bp 470 bp wt Mlo Lawina DE 321 bp 195, 77, 49 bp 470 bp wt Mlo Lysimax DK 321 bp 195, 77, 49 bp 530 bp mlo-11 Magda NL 321 bp 195, 77, 49 bp 530 bp mlo-11 Merlin US 321 bp 195, 77, 49 bp 470 bp wt Mlo Peggy DE 321 bp 195, 77, 49 bp 470 bp wt Mlo Prosa AT 321 bp 195, 77, 49 bp 470 bp wt Mlo Rattan CA 321 bp 195, 77, 49 bp 470 bp wt Mlo Rupal SE 321 bp 195, 77, 49 bp 470 bp wt Mlo Samson CA 321 bp 195, 77, 49 bp 470 bp wt Mlo Steffi DE 321 bp 195, 77, 49 bp 470 bp wt Mlo Wanubet US 321 bp 195, 77, 49 bp 470 bp wt Mlo Washonubet US 321 bp 195, 77, 49 bp 470 bp wt Mlo L-3118 LV 321 bp 195, 77, 49 bp 530 bp mlo-11 PR-2797 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo PR-3005 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo PR-3282 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo PR-3297 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo PR-3335 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo PR-3345 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo PR-3348 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo PR-3351 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo PR-3353 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo PR-3455 LV 321 bp 195, 77, 49 bp 530 bp mlo-11 PR-3487 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo PR-3520 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo PR-3522 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo PR-3524 LV 321 bp 195, 77, 49 bp 470 bp wt Mlo 1 Length of PCR amplicons and restriction fragments is predicted from the known sequence of the Mlo locus. 2 wt Mlo – wild type Mlo allele. 80 ______AGRONOMIJAS VĒSTIS (Latvian Journal of Agronomy), No.11, LLU, 2008____ 3 indel – PCR fragment length polymorphism caused by an insertion of transposable element (Piffanelly et al., 2004). While mlo-5, mlo-9 and mlo-11 alleles are mostly used in plant breeding (http://www.crpmb.org/mlo/), there is still a need for the characterization of additional mutant alleles both for the understanding of the Mlo function in plants and as a material for breeding. The complete coding sequence of the Mlo gene from the 792-99 mutant and the variety Maja was obtained and used to identify the cause of mutation. A single base exchange at position 2004 relative to the ATG codon was identified as the only difference between the mutant 792-99 and the wild type variety Maja (Figure 1A). Figure 1. Molecular markers for the mlo alleles A Structure of the Mlo gene with the mlo-5 and mlo-9 mutations indicated. A G to A transition in the 10th exon is a novel mutation identified in the variety Maja. Boxes represent exons; filled boxes represent coding regions, open boxes represent 5’- and 3’-untranslated regions. B Molecular marker-based detection of mlo-9 and mlo-11 alleles in barley hybrids. Lanes 1 – 4 – four hybrid lines analyzed with the mlo-9 CAPS marker (Schulze-Lefert et al., 1998); lane 5 – MW marker; lanes 6 – 9 – the same four hybrid lines analyzed with the mlo-11 indel marker (Piffanelli et al., 2004). The mutation caused the amino acid Gly to Arg exchange at position 318 of the MLO protein, a position that has also been mutated in the mlo-27 allele (Gly to Glu) (Piffanelli et al., 2002). Thus, the predicted Gly to Arg exchange was likely to be responsible for the observed resistance phenotype and further confirmed the functional significance of this amino acid residue. Powdery mildew is still one of the most damaging barley diseases in Europe regnising extensive use of pesticides. The exploitation of natural plant disease resistance provides a sustainable solution for pest control, however, breeding for disease resistance is often complicated because of difficulty of carrying out field phenotyping tests and the linkage drag of undesired traits with resistance genes. Molecular markers have the potential to facilitate plant breeding by the enabling one to carry out selection at seedling stage based on molecular marker genotypes and thus avoiding time- and labor-intensive field tests (Varshney et al., 2005). Molecular markers also provide the opportunity to screen a large number of progeny to select for the rare recombinants that uncouple the resistance from closely linked deleterious alleles (Thomas et al., 1998). Acknowledgements The study was funded by the Latvian National programme in agrobiotechnology, the Latvian Council of Science project 07.2055 and University of Latvia grant ZP-59. References 1. 2. Buschges R., Hollricher K., Panstruga R., Simons G., Wolter M., Frijters A., Van Daelen R., Van Der Lee T., Diergarde P., Groenendijk J., Topsch S., Vos P., Salamini F. and Schulze-Lefert P. (1997) The barley Mlo gene: A novel control element of plant pathogen resistance. Cell, 88, 695-705. Edwards K., Johnstone C. and Thompson C. (1991) A simple and rapid method for the preparation of plant genomic DNA for PCR analysis. Nucleic Acids Res, 19, 1349. 81 ______AGRONOMIJAS VĒSTIS (Latvian Journal of Agronomy), No.11, LLU, 2008____ 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. Halterman D., Zhou F., Wei F., Wise R. and Schulze-Lefert P. (2001) The MLA6 coiled-coil, NBS-LRR protein confers AvrMla6-dependent resistance specificity to Blumeria graminis f. sp. hordei in barley and wheat. Plant J, 25, 335-348. Halterman D.A., Wei F. and Wise R.P. (2003) Powdery mildew-induced Mla mRNAs are alternatively spliced and contain multiple upstream open reading frames. Plant Physiol, 131, 558-567. Jørgensen H. (1992) Discovery, characterization and exploitation of Mlo powdery mildew resistance in barley. Euphytica, 63, 141-152. Konieczny A. and Ausubel FM. (1993) A procedure for mapping Arabidopsis mutations using codominant ecotype-specific PCR-based markers. Plant J, 4, 403-410. Mejlhede N., Kyjovska Z., Backes G., Burhenne K., Rasmussen S.K. and Jahoor A. (2006) EcoTILLING for the identification of allelic variation in the powdery mildew resistance genes mlo and Mla of barley. Plant Breeding, 125, 461-467. Ovesna J., Polakova K., Kucera L. and Rulcova J. (2003) SNP typing in cereals: comparison of SSCP and SNaPShot markers using the barley Mlo locus as a model. Czech J Genet Plant Breed, 39, 109-112. Piffanelli P., Zhou F., Casais C., Orme J., Jarosch B., Schaffrath U., Collins N.C., Panstruga R. and Schulze-Lefert P. (2002) The barley MLO modulator of defense and cell death is responsive to biotic and abiotic stress stimuli. Plant Physiol, 129, 1076-1085. Piffanelli P., Ramsay L., Waugh R., Benabdelmouna A., D'Hont A., Hollricher K., Jorgensen J.H., Schulze-Lefert P. and Panstruga R. (2004) A barley cultivation-associated polymorphism conveys resistance to powdery mildew. Nature, 430, 887-891. Schulze-Lefert P., Maria J., Panstruga R. and Bueschges R. (1998) Polynucleotide and its use for modulating a defence response in plants . WO1997GB02046 19970729. Shen Q.H., Zhou F., Bieri S., Haizel T., Shirasu K. and Schulze-Lefert P. (2003) Recognition specificity and RAR1/SGT1 dependence in barley Mla disease resistance genes to the powdery mildew fungus. Plant Cell, 15, 732-744. Staden R. (1996) The Staden sequence analysis package. Mol Biotechnol, 5, 233-241. Stanca M. (2003) Diversity in abiotic stress tolerance. In: Diversity in barley. von Bothmer R., van Hintum T., Knuepffer H. and Sato K. (eds.) Elsevier, Amsterdam, 179-199. Tacconi G., Baldassarre V., Collins N.C., Bulgarelli D., Stanca A.M. and Vale G. (2006) Haplotype characterization and markers at the barley Mlo powdery mildew resistance locus as tools for markerassisted selection. Genome, 49, 864-872. Thomas W.T.B., Baird E., Fuller J.D., Lawrence P., Young G.R., Russell J., Ramsay L., Waugh R. and Powell W. (1998) Identification of a QTL decreasing yield in barley linked to Mlo powdery mildew resistance. Molecular Breeding, 4, 381-393. Thompson J.D., Gibson T.J., Plewniak F., Jeanmougin F. and Higgins D.G. (1997) The CLUSTAL_X windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. Nucleic.Acids.Res, 25, 4876-4882. Varshney R.K., Graner A. and Sorrells M.E. (2005) Genomics-assisted breeding for crop improvement. Trends Plant Sci., 10, 621-630. Wei F., Gobelman-Werner K., Morroll S.M., Kurth J., Mao L., Wing R., Leister D., Schulze-Lefert P. and Wise R.P. (1999) The Mla (powdery mildew) resistance cluster is associated with three NBS-LRR gene families and suppressed recombination within a 240-kb DNA interval on chromosome 5S (1HS) of barley. Genetics, 153, 1929-1948. Weibull J., Walther U., Sato K., Habekuss A., Kopahnke D. and Proeseler G. (2003) Diversity in resistance to biotic stresses. In: Diversity in barley. von Bothmer R., van Hintum T., Knuepffer H. and Sato K. (eds.) Elsevier, Amsterdam, 143-178. Wolter M., Hollricher K., Salamini F. and Schulze Lefert P. (1993) The mlo resistance alleles to powdery mildew infection in barley trigger a developmentally controlled defence mimic phenotype. Mol Gen Genet, 239, 122-128. Zhou F., Kurth J., Wei F., Elliott C., Vale G., Yahiaoui N., Keller B., Somerville S., Wise R. and Schulze-Lefert P. (2001) Cell-autonomous expression of barley Mla1 confers race-specific resistance to the powdery mildew fungus via a Rar1-independent signaling pathway. Plant Cell, 13, 337-350. MOLEKULĀRO MARĖIERU PIELIETOJUMS MILTRASAS IZTURĪBAS LOKUSA MLO RAKSTUROJUMAM EIROPAS MIEŽU ŠĖIRNĒS UN SELEKCIJAS LĪNIJĀS Kokina A, LegzdiĦa L, BērziĦa I, Bleidere M, Rashal I un Rostoks N. Miltrasa ir plaši izplatīta miežu slimība, ko izraisa mikroskopiskā sēne Blumeria (Erysiphe) graminis f.sp. hordei. Slimību var kontrolēt izmantojot pesticīdus, taču to pielietošana paaugstina 82 ______AGRONOMIJAS VĒSTIS (Latvian Journal of Agronomy), No.11, LLU, 2008____ ražošanas izmaksas un nav pieĦemama bioloăiskajā lauksaimniecībā. Miežiem piemīt dabiskā izturība pret miltrasu, ko nosaka vairāki genoma rajoni, no kuriem svarīgākie ir Mlo un Mla lokusi. Dabiskas vai inducētas recesīvas mutācijas Mlo lokusā nodrošina plaša spektra izturību pret gandrīz visiem zināmajiem miltrasas patotipiem. Mlo gēns ir klonēts un vairākas mutācijas gēna DNS sekvencē, kas piešėir slimību izturību, ir zināmas. Mēs raksturojām jaunu mlo allēli mutantā, kas iegūts no šėirnes Maja, kurā notikusi aminoskābes Gly nomaiĦa par Arg 318 pozīcijā. Lai raksturotu mlo miltrasas izturību Eiropas miežu šėirnēs, kā arī Latvijas un ārzemju selekcijas līnijās, tika izmantoti CAPS marėieri mlo-5, mlo-9 un mlo-11 allēlēm. Iegūtie rezultāti apstiprina molekulāro marėieru pielietojuma perspektīvu pret miltrasu izturīgu miežu hibrīdu selekcijā. A COMPARISION OF THE YIELD AND QUALITY TRAITS OF WINTER AND SPRING WHEAT Koppel, R., Ingver, A. Jõgeva Plant Breeding Institute, Aamisepa 1, Jõgeva alevik, Estonia, 48 309, phone +372 77 66 901, e-mail: [email protected] Abstract Traditionally winter wheat is known by its higher yield potential and spring wheat by better baking quality. In this investigation we studied how yield and quality traits of spring and winter wheat differed at the Jõgeva PBI trials during 2004-2007. Yield and 1000 kernel weight of winter wheat exceeded spring wheat every year. Spring wheat had higher protein and gluten content and volume weight. There was no clear trend for the falling number and gluten index. According to variance analyses, the value of yield and 1000 kernel weight were determined by the wheat type (spring or winter) but other characteristics were more affected by the weather conditions of a particular year. The effect of the weather conditions for the year was greater for yield, 1000 kernel weight, protein and gluten content, bread loaf volume and dough stability for the both types of wheat. For falling number the influence of the year was greater than that of the variety of spring wheat and the influence was revesed for winter wheat. Volume weight depended more on the weather for spring wheat and on the variety for winter wheat. Key words: spring wheat, winter wheat, quality, yield Introduction The climatic conditions in Estonia are suitable for cultivation of the both wheat types – spring and winter wheat. The acreage of wheat cultivation has enlarged from 78 to 102 thousand ha during the last 4 years (2004-2007). The acreage share of winter wheat is 1/3 smaller than that of spring wheat (but has a tendency to increase). Traditionally winter wheat is known for its higher yield potential and spring wheat for its better baking quality (Swenson, 2006; Baker and Townley-Smith, 1986). Yield and quality potential is largely determined by the variety, but the extent to which this potential is achieved depends upon factors such as seasonal weather conditions. Higher grain yields are usually associated with lower protein concentration (Terman et al., 1969, Blackman and Payne, 1987). The protein is a primary quality component of cereal grains. The protein concentration is influenced by both environmental and genotypic factors that are difficult to separate (Fowler et al, 1990). The protein content of wheat grains can vary from 6% up to as much as 25%, depending upon the growing conditions (Blackman and Payne, 1987). Terman et al. (1969) noted that protein content varied more widely among locations than among varieties at the growing location. Differences among cultivars tended to be greatest under optimum growth conditions (Terman, 1979). Protein content and protein quality have been also shown to be significant for baking quality (Johanson and Svensson, 1998). Fredericson et al. (1997, 1998) found that protein content was positively correlated with wet gluten content, farinogram dough stability and bread loaf volume. The great majority of wheat products are adversely affected by alfa-amylase. The activity of alfaamylase can be described by the falling number test. High levels of alfa-amylase activity in the 83