(Editorial comment)

Dr. K. Sato summarized the meeting report of "The Third Triticeae Meeting of Japan, 2008" held on December 6 in Kurashiki, Okayama, Japan. We circulate the abstracts of oral presentations and the titles of poster presentations as edited by Dr. Sato.

The Third Triticeae Meeting of Japan, 2008

Kazuhiro Sato

Research Institute for Bioresources, Okayama University, Kurashiki, 710-0046, Japan

E-mail: kazsato@rib.okayama-u.ac.jp

The third Triticeae Meeting of Japan was held at Research Institute for Bioresources, Okayama University December 6, 2008. More than 100 researchers and students participated in the meeting (Fig. 1). Two special lectures by Profs. Kazuyoshi Takeda and Kazuhiko Noda were given under co-organization with Sanyo Breeding Workshop. Two plenary talks from barley and wheat, other five talks from recent Triticeae scientific activities were presented. Thirty posters with short oral explanation were presented mainly by young scientists. Summary of presentations were described below.

Another meeting was organized by Okayama University at the same place. The title was “Identification of important genes and their application to breeding in barley”. Recent activities of barley genome research and gene isolation were presented. Invited lectures were also presented by Dr. Nils Stein, IPK, representing International Barley Sequencing Consortium and Dr. Etienne Paux, INRA, for wheat chromosome 3B analysis. These two-day activities reviewed the advancements of Triticeae science internationally and gave good opportunity for young scientists and researchers in other fields to know the current and ongoing activities on Triticeae science.   

ABSTRACTS & TITLES

Oral Presentation

O1. Genetical studies on barley ; A special lecture

Kazuyoshi Takeda

Research Institute for Bioresources, Okayama University, Kurashiki, 710-0046, Japan

1) A brief history of Sanyo branch of Japanese Society of Breeding was introduced.

2) History of Barley Germplasm Center 

In 1942 the first scientific paper on the barley genetics was published by Ryuhei Takahashi, a leader of Japanese barley genetics. Barley germplasm preservation project was funded by Monbusho in 1967. Barley Germplasm Preservation Lab. was established in 1979, and it was expanded as Barley and Wild Plant Resource Center in 1997. In Barley division, we preserve ca. 14,000 germplasm accessions, DNA resources and their on-line database systems.

3) Selected topics of barley genetic studies

Semi-dwarf “uzu”: In 1942 Dr. R. Takahashi published the first paper concerning the varietal variation of coleoptile length, i.e. long vs. short.  The short type was named “uzu” after the dwarf mutant of the morning glory.  The uzu varieties were distributed in the south part of Japan and the Korean peninsula.  In China, uzu varieties were grown more than one million ha in 1960~1970s.  The trait is controlled by a single nucleotide mutation caused an amino-acid change which resulted in brasinosteroid insensitivity.

Diazinon sensitivity: Varietal variation of the sensitivity to an insecticide diazinon was found.  The sensitivity is caused by a single dominant gene named Diz located on chromosome 7H.  Out of 5,560 varieties tested, 708 were sensitive to diazinon and exclusively distributed in west of India. Varieties with Diz in east of China were western origin. Thus, Diz is an important marker trait to study the phylogeny of barley.

Deep seeding tolerance: Because the topsoil in semi-arid regions is very dry.  Seeds are usually sown deep.  Thus, varieties have to be capable to emerge from the depth.  The deep-seeding tolerance in more than 4,000 barley accessions was evaluated.  The varietal variation was very large and deep seeding tolerant varieties elongate the first internode which usually does not occur when seeds were sown shallow.  The major QTLs for the deep seeding tolerance were found on chromosome 5H and 7H.

O2. Nucleotide-substitution rate of the B-genome donor species of wheat; a special lecture

Kazuhiko Noda

Research Institute for Bioresources, Okayama University, Kurashiki, 710-0046, Japan

Phylogenetic studies of hexaploid wheat, Triticum aestivum (AABBDD), have shown that Aegilops speltoides (SS) is a candidate species for the B-genome donor; however, this finding remains controversial. It has been suggested that the high rate of nucleotide change just after polyploidisation and during diversification of Ae. speltoides may cause ambiguity in predicted B-genome ancestry. We compared 29 orthologous dihydroflavonol-4-reductase (DFR) genes from the Triticum-Aegilops complex, the synthetic wheat, barley and maize, and estimated the amount of nucleotide change among these DFRs through the use of the Molecular Evolutionary Genetics Analysis (MEGA) software. Ae. speltoides (SS) was the closest species to the B and G genomes of tetraploid (T. turgidum [AABB]), T. araraticum [AAGG]) and hexaploid wheat (T. aestivum [AABBDD]). However, there were more nucleotide differences between Ae. speltoides and the B and G genomes than between T. urartu (AA) and the A genome of tetraploid and hexaploid wheats or between Ae. squarrosa (DD) and the D genome of hexaploid wheat. Polyploidisation does not appear to induce a high rate of nucleotide change because no significant change was detected in the synthetic hexaploid wheat. The substitution-rate heterogeneity test showed that a high rate of nucleotide change occurred in Ae. speltoides compared with nucleotide changes in the other species of the Sitopsis section (SS). The high rate of nucleotide change in Ae. speltoides might have caused ambiguity in predicted B-genome ancestries.

O3. Multiple molecular events responsible for barley domestication

Takao Komatsuda

National Institute of Agrobiological Sciences (NIAS), Plant Genome Research Unit, Kan-non-dai 2-1-2, Tsukuba, Ibaraki 305 8602, Japan.

Early cultivators of barley (Hordeum vulgare ssp. vulgare) selected a spike phenotype with non-brittle rachis. Two genes responsible for non-brittle rachis (btr1 and btr2) were genetically detected more than 50 years ago, and existence of the two genes allowed Dr. R. Takahashi, Okayama University, Kurashiki, to suggest at least two independent origins of cultivated barley. A physical map covering the btr1 and btr2 genes has been constructed for the isolation of these genes. Non-brittle rachis was followed by a six-rowed spike that stably produced three times the usual grain number during domestication. Six-rowed spike 1 (Vrs1) was cloned. Vrs1 encoded a homeodomain leucine zipper I?class protein (HD-ZIP I), a potential transcription factor. Vrs1 is expressed only in lateral spikelet primordia of the early developmental stage. Analysis of plenty of mutant lines allowed the gene identification. In addition to many mutational events detected at the coding sequence of Vrs1 gene, mutational event at the regulatory regions of Vrs1 was suggested in five mutant lines. Three independent origins of six-rowed barley were caused by loss-of-function mutation of the homeobox gene, while another origin showed no DNA changes throughout the coding region of the Vrs1 gene leaving its mutational event unknown. Report on the isolation of naked caryopsis (nud) indicated a single origin of naked barley of the world. Seed dormancy is controlled by rather complex genetic system, QTL, and SD1 and SD2, the major QTL, would be targets for gene isolation. Origin of vernalization non- requirement (Vrn-H1 or Sgh2) was reported to be multiple, while photoperiod insensitive gene ppd-H1 was suggested to be of a single origin. Molecular cloning of genes responsible for domestication and adaptation may allow inferring developmental process of cultivated barley as an important crop.

O4. Genome resources and functional genomics in common wheat

Yasunari Ogihara

Kihara Institute for Biological Research, Yokohama City University, Yokohama 244-0813, Japan

Because wheat harbors huge genome size and is characteristic of its polyploidy nature, we have conducted comprehensive collections of expressed sequence tags (ESTs) in common wheat for several years.  Up to now, 55 cDNA libraries derived from tissues during the wheat life cycle as well as stress-treated tissues were constructed.  Several thousand colonies were randomly selected from each of these cDNA libraries and their inserts were sequenced from both of 5’- and 3’ ends. Sequence data of about one-million ESTs are now available.  These ESTs were grouped into about 90 thousands homoeologs and 38 thousands gene clusters with CAP3/phrap and BLAST methods.  These contigs were estimated to cover more than 90 % of expressed wheat genes.  By computing ESTs, correlated expression patterns of genes across the tissues (Virtual Display: VD) were monitored including stress-treated tissues.  Thus, genes specifically induced and/or suppressed by certain stresses were able to be selected from the VD.  These genes were annotated with the BLAST search. Furthermore, by using these contigs, we had constructed oligo DNA microarray spotting 38K wheat gene probes under collaboration with Agilent Co. Ltd.  This array was applied to select salt (NaCl) responsive genes in common wheat. We also promoted systematic survey and sequencing of the wheat full-length cDNA clones to carry out gene annotation in the wheat genome and functional genomics of wheat. These functional genomics data of wheat should provide powerful tools for wheat breeding.

O5. Molecular mechanisms controlling adhesion of hulls to caryopses in barley.

Shin Taketa

Research Institute for Bioresources, Okayama University, Kurashiki, Okayama, 710-0046, Japan

Typical barley cultivars have caryopses with adhering hulls at maturity, known as covered (hulled) barley. However, a few barley cultivars are a free-threshing variant called naked (hulless) barley. The covered/naked caryopsis is controlled by a single locus (nud) on chromosome arm 7HL. Such differentiation in caryopsis types is unique to the barley crop. By means of positional cloning, it was concluded that an ERF (ethylene response factor) family transcription factor gene controls the covered/naked caryopsis phenotype. This conclusion was supported by (1) fixation of the 17-kb deletion, harboring the ERF gene, among all 100 naked cultivars studied, (2) two x-ray induced nud alleles with a DNA lesion at a different site, each affecting the putative functional motif, and (3) gene expression strictly localized to the testa. Available results indicate the monophyletic origin of naked barley in the world. The Nud gene has homology to the Arabidopsis WIN1/SHN1 transcription factor gene, whose deduced function is control of a lipid biosynthesis pathway. Staining with a lipophilic dye (Sudan Black B) detected a lipid layer on the pericarp epidermis only in covered barley. It is suggested that, in covered barley, the contact of the caryopsis surface, overlaid with lipids to the inner side of the hull, generates organ adhesion. Details were reported in our recent publication, Taketa et al. PNAS 4062-4067(2008).

O6. “The origin of bread wheat” revisited - fieldwork, diversity analysis, and QTL mapping

Yoshihiro Matsuoka

Department of Bioscience, Fukui Prefectural University, 4-1-1 Matsuoka-kenjojima, Eiheiji-cho, Yoshida-gun, Fukui 910-1195, Japan

Bread wheat (Triticum aestivum L. ssp. aestivum) has a hexaploid genome (genome constitution AABBDD) derived from a hybrid cross between a cultivated form of tetraploid Triticum wheat (T. turgidum L., genome constitution AABB) as the female parent and a wild diploid species Aegilops tauschii Coss. (genome constitution DD) as the male parent. The hybrid cross is supposed to have produced a fertile triploid F₁ hybrid (genome constitution ABD) that spontaneously set hexaploid seeds by producing unreduced gametes in male and female gametogenesis.  Bread wheat represents cases in which the genetic relationships between crops and their relatives are known.  Important questions, however, remain concerning the genetic and ecological mechanisms that underlie the early stages of the evolution of bread wheat.  How often does Ae. tauschii grow in the T. turgidum fields?  Under what environmental conditions does the T. turgidum-Ae. tauschii hybrid cross successfully take place?  Which Ae. tauschii population has the ability to produce the fertile triploid F₁ hybrid with T. turgidum?  To what extent is the fertility of the triploid F₁ hybrid genetically controlled?  In the last four years, we addressed these questions by (1) fieldwork to examine the current ecological status of Ae. tauschii and T. turgidum in northern Iran, (2) diversity analysis to examine the natural variation for fertile T. turgidum-Ae. tauschii F₁ hybrid formation, and (3) QTL mapping to examine the genetic basis of the T. turgidum-Ae. tauschii F₁ hybrid fertility.  In this talk, I will summarize the results of those studies and discuss advances in understanding the evolution of bread wheat. 

O7.Low temperature stress signal pathways in wheat

Fuminori Kobayashi

Research Fellow of the Japan Society for the Promotion of Science, Plant Genome Research Unit, National Institute of Agrobiological Sciences, Kan-non-dai 2-1-2, Tsukuba, Ibaraki 305-8602, Japan

Low temperature induces and/or enhances expression of numerous Cor (cold-responsive)/Lea (late embryogenesis abundant) genes, and accumulated COR/LEA proteins promote the development of freezing tolerance by protecting cellular components. In wheat, a number of low temperature-inducible Cor/Lea genes have been isolated, and genetic maps of major loci and QTLs affecting cold/freezing tolerance have been constructed. Fr-1 (Frost resistance-1) and Fr-2 are well known to be major loci determining winter hardiness. Fr-1 controls development of freezing tolerance and Cor/Lea gene expression through transcriptional activation of the CBF gene family, tandemly located on the Fr-2 loci. Wcbf2, Wdreb2 and Wlip19 out of four cold-responsive transcription factor genes identified in our previous studies were transcriptionally activated through Fr-1 under low temperature conditions. Transgenic tobacco plants expressing either these transcription factors showed a significant increase in freezing tolerance. The direct interaction between the transcription factors and wheat Cor/Lea promoters was in vivo confirmed using the wheat cultured cells and the transgenic tobacco plants. These results indicate that WCBF2, WDREB2, WABI5 and WLIP19 act as transcriptional regulators to activate Cor/Lea gene expression under low temperature conditions. In other words, various stress-responsive transcription factors cooperatively function in development of cold/freezing tolerance in wheat. On the other hand, it is well known that abscisic acid (ABA) also regulates responses to environmental stress. In fact, two wheat lines, ‘EH47-1’ (ABA-less-sensitive mutant) and ‘Mutant ABA 27’ (ABA-hypersensitive mutant), showed significantly increased freezing tolerance comparing with their parental lines, suggesting that ABA sensitivity is associated with determination of freezing tolerance level in wheat. Four QTLs for ABA sensitivity were identified on chromosomes 1B, 2A, 2B and 6D in common wheat seedling. Because of limited information about functional roles of the ABA signal pathways on activation of the cold-responsive genes, further studies should be required to confirm functional relationship between each of the identified QTLs and cold/freezing tolerance.

O8. What is the real model for flowering gene network in wheat and barley?

Koji Murai

Department of Bioscience, Fukui Prefectural University, 4-1-1 Matsuoka-kenjojima, Eiheiji-cho, Yoshida-gun, Fukui 910-1195, Japan

In cereal crops such as wheat and barley, heading time associated with the timing of floral transition (flowering) is an important character because of its influence on the adaptability to various environmental conditions. Several orthologous genes have been identified for flowering regulation in wheat and barley, suggesting that the common regulatory mechanisms are involved in the flowering of wheat and barley. Among the genes for flowering regulation, VRN1 (identical with WAP1), VRN2 and FT were identified to play the central roles in flowering. VRN1 and FT are activators of flowering, but VRN2 is a repressor. Two different models for flowering gene network have been presented by Jorge Dubcovsky’s group and Ben Travaskis’s group. According to our mutant and transgenic studies, the third model can be presented. In our model, VRN1 is upstream of FT and possibly acts with CO to activate FT expression under LD conditions. Like in Arabidopsis and rice, FT proteins could be the florigen that moves from the leaves into the SAMs to determine floral meristem identity in wheat and barley. VRN2 is down-regulated by vernalization, and suppresses the VRN1 expression. Furthermore, VRN2 is down-regulated by FT. Consequently, a feedback triangle of VRN1-FT-VRN2 could be the central mechanism in the wheat flowering. Our model can explain why VRN1 represses VRN2 expression, and why VRN2 is epistatic to VRN1. It is important to notice that the gene interactions shown in the model are events occurring in leaves not in SAMs.

O9. Wheat Research In India: Current Status

H. S. Balyan

Department of Genetics and Plant Breeding

Ch. Charan Singh University, Meerut-250 001 India

Email: hsbalyan@gmail.com

Wheat is one of the most important grain crops of India, which is second to only rice in production. India ranks first in terms of area under wheat cultivation and second in terms of production and consumption after China. Current wheat production in India contributes ~8% to the total world’s wheat production. To maintain self-sufficiency in food grains and to meet the projected demands of wheat grain in 2025, the annual production of wheat and rice needs to increase by 2 mt every year.  With increasing urbanization and changes in life style, the demand for diversified end-products of wheat is also rising steadily. To meet these challenges, wheat research currently is focused on development of wheat varieties with improved (a) yield potential, (b) tolerance to biotic and abiotic stress, (c) water use efficiency, (d) micronutrient (Zn and Fe) composition, and (d) end-use quality. An overview of the efforts to meet the above challenges through classical plant breeding including the use of alien species and molecular approaches will be presented. Significant efforts made towards development and use of molecular markers for introgression and pyramiding the genes/QTL for different traits including leaf rust resistance and grain quality will be discussed in some details with emphasis on the work done during the past few years in our laboratory. The role of India in wheat genome sequencing will also be presented.

Poster Presentation

P1. Sanae Shimada (Dep. Biosci., Fukui Pref. Univ.) Why a wheat line Cho-gokuwase is so early heading?

P2. Naoki Shitsukawa (Dep. Biosci., Fukui Pref. Univ.) Transcription variant in wheat class B MADS-box gene WAP3.

P3. Hiroko Kinjo (Dep. Biosci., Fukui Pref. Univ.) Is WFUL2 is a wheat class A MADS box gene?

P4. Yuki Fujiwara (Dep. Biosci., Fukui Pref. Univ.) Heading characters in synthetic hexaploid wheat and its ancestral species.

P5. Megumi Suzuki (Dep. Biosci., Fukui Pref. Univ.) Epigenetic expression mechanism in the homoeologs of wheat class E MADS-box gene WLHS1.

P6. Tonooka, T., E..Aoki, T. Yoshioka (Natl. Inst. Crop Sci., NARO) Breeding of barley with new useful quality in NICS.

P7. Matsuoka, Y. ¹ , S. Takumi ² , T. Kawahara ³ ( ¹ Fukui Pref. Univ., ² Laboratory of Plant Genetics, Graduate School of Agricultural Science, Kobe Univ., ³ .Graduate School of Agriculture, Kyoto Univ.) Flowering time diversification and dispersal in central Eurasian wild wheat Aegilops tauschii Coss.: genealogical and ecological framework.

P8. Matsunaka, H., M. Chono, M. Seki (Natl. Inst. Crop Sci., NARO) Screening of new genotype of R-A1 and its pedigrees.

P9. Seki, M., M. Chono, H. Matsunaka (Natl. Inst. Crop Sci., NARO) Breeding of near-isogenic lines for Ppd-1, controlling photoperiodic response in wheat.

P10. Kawakami , K. ¹ , T. Kawahara ² , H. Nishida ¹ , Y. Akashi ¹ , K. Kato ¹   ( ¹ Grad. Sch. Natural Sci. Tech., Okayama U., ² Grad. Sch. Agr., Kyoto U.)  Molecular genetic analysis of vernalization response gene in wild species of diploid wheat.

P11. Sibai, S., Y. Omura, Y. Akashi, H. Nishida and K. Kato  (Grad. Sch. Natural Sci. Tech., Okayama U.) Evolution and diversification of spring type wheat - Geographical variation in the sequence variation at Vrn-D1 locus.

P12. Matsumoto, A. ¹ , T. Tonooka ² , D. Ishihara ¹ , E. Aoki ² , T. Yoshioka ² , Y. Akashi ¹ , H. Nishida ¹ and K. Kato ¹ ( ¹ Grad. Sch. Natural Sci. Tech., Okayama U., ² Natl. Inst. Crop Sci.) Genetic diversity of heading time related genes of barley and its relation with heading date in the field.

P13. Mizuno, N., S. Takumi (Lab. Plant Genetics, Grad. Sch. Agr. Sci., Kobe Univ.) Transcriptome profiling of hybrid necrosis in hybrids between emmer wheat and Aegilops tauschii.

P14. Kajimura, T., N. Mizuno, S. Takumi (Lab. Plant Genetics, Grad. Sch. Agr. Sci., Kobe Univ.) Identification of senescence-associated ESTs in common wheat.

P15. Kurahashi, Y., A. Terashima, S. Takumi (Lab. Plant Genetics, Grad. Sch. Agr. Sci., Kobe Univ.) Comparative study of ABA sensitivity in D-genome-varied synthetic hexaploid wheat lines.

P16. Takumi, S. ¹ , E. Nishioka ¹ , Y. Matsuoka ² ( ¹ Lab. Plant Genetics, Grad. Sch. Agr. Sci., Kobe Univ., ² Fukui Pref. Univ.)    Intraspecific variation of Aegilops tauschii revealed by spikelet morphology.

P17. Garg, M., H. Tanaka, H. Tsujimoto (Fac. Agr., Tottori Univ.) Exploitation of the variation of Agropyron elongatum and Aegilops geniculata for improvement of bread making quality.

P18. Ishii, T., T. Ueda, H. Tanaka, H. Tsujimoto (Grad. Sci. Agr., Tottori Univ.) Behavior of pearl millet chromosomes in Triticeae-pearl millet hybrid embryos.

P19. Sakata, T., Y. Taguchi, H. Tanaka, H. Tsujimoto (Grad. Sch. Agr., Tottori Univ.) Production of wheat lines with the fragments of alien chromosome by pollen irradiation method.

P20. Tanaka, K., M. Shimada, H. Tanaka, H. Tsujimoto (Grad. Sch. Agr., Tottori Univ.) Application of TILLING to detection of polymorphism in SSR markers in wheat.

P21. Ban, T. ^{1 , 2} , H. Buerstmayr ³ ,. J.A. Anderson ⁴ ( ¹ KIBR, Yokohama City Univ., ² CIMMYT, ³ IFA-Tulln, Austria, ⁴ UMN, USA) Consensus map of Fusarium head blight resistance QTL in wheat.

P22. Arifi, M. ¹ , ² ( ¹ MAIL ARIA, Afghanistan, ² KIBR, Yokohama City Univ.) Wheat production and breeding techniques in Afghanistan.

P23. Manickavelu A.1, K. Kawaura1, N. Yahiaoui2, B. Keller2, Y. Ogihara1 (1KIBR, Yokohama City U., 2Inst. Plant Biology, University of Zurich) Identification of new O-methyltransferase gene in common wheat induced by fungal pathogen.

P24. Kouyama S, K. Kawaura, Y. Ogihara (KIBR, Yokohama City U.) Analyses of global gene expression patterns in wheat during the allopolyploidization course.  

P25. Saito M., M. Isshiki, K. Kawaura, Y. Ogihara (KIBR, Yokohama City U.) Molecular analyses of seed storage proteins in bread wheat.

P26. Takaku M., K. Kawaura, Y. Ogihara (KIBR, Yokohama City U.) Variation of the spike morphology in TILLING lines of common wheat.

P27. Hoshikawa A., Y. Tetsu, K. Kawaura, Y. Ogihara (KIBR, Yokohama City U.) Functional analysis of wheat NAC transcription factors in response to salt stress.

P28. Yasumoro,M,.K.Kawaura,Y.Ogihara (KIBR.,Yokohama City U.) Molecular study on regulation systems of gene expression in hexaploid wheat.

P29. Tetsu Y., M. Saito, A. Hoshikawa, K. Kawaura, Y. Ogihara (KIBR, Yokohama City U.) Production of transgenic lines suppressed NAC genes with RNA in Triticum aestivum.