Brachypodium Sylvaticum Research Articles

Region and site conditions affect phenotypic trait variation in five forest herbs

Phenotypic plasticity is the ability of organisms to express different phenotypes under different environmental conditions. It may buffer individuals both against short-term environmental fluctuations and long-term effects of global change. A plastic behaviour in response to changes in the environment may be especially important in species with low migration rates and colonization capacities, such as in many forest plants in present-day fragmented landscapes. We compared the phenotypic trait variation (used as a proxy for the amount of phenotypic plasticity) of five forest herbs (Brachypodium sylvaticum, Circaea lutetiana, Impatiens noli-tangere, Sanicula europaea and Stachys sylvatica) between two regions in Germany that differ in their overall environmental conditions (Bremen in the northwest, Freiburg in the southwest; 5 species × 2 regions × 8–15 populations × 25–50 individuals). In addition, we measured light intensity and important soil parameters (soil pH, moisture, K, P and N) in all populations. We found consistent differences in trait variability between the two regions in several species. In Brachypodium and Stachys both vegetative and reproductive traits were more variable in Freiburg. Similarly, reproductive traits of Impatiens and Sanicula appeared to be more variable in Freiburg, while in both species at least one of the vegetative traits was more variable in Bremen. Mean local environmental conditions also affected trait variation; in most of the species both vegetative and reproductive traits were more variable in sites with higher nutrient contents and higher light availability. Across all traits and both regions, seed or fruit production was most variable. In summary, at least some of the studied forest herbs appear to respond strongly to large-scale environmental differences, showing a higher trait variability in the more southern region. Given the assumption that phenotypic trait variation is positively associated with phenotypic plasticity, we conclude that these populations may more easily respond to changes in the environment.

Host Status of False Brome Grass to the Leaf Rust Fungus Puccinia brachypodii and the Stripe Rust Fungus P. striiformis.

Purple false brome grass (Brachypodium distachyon) has recently emerged as a model system for temperate grasses and is also a potential model plant to investigate plant interactions with economically important pathogens such as rust fungi. We determined the host status of five Brachypodium species to three isolates of Puccinia brachypodii, the prevalent rust species on Brachypodium sylvaticum in nature, and to one isolate each of three formae speciales of the stripe rust fungus P. striiformis. Two P. striiformis isolates produced sporulating lesions, both in only one of the tested interactions, suggesting a marginal host status of B. distachyon. P. brachypodii formed sporulating uredinia on the five Brachypodium species tested, and a range of reactions was observed. Surprisingly, the B. sylvaticum-derived rust isolates were more frequently pathogenic to B. distachyon than to their original host species. The B. distachyon diploid inbred lines, developed and distributed as reference material to the Brachypodium research community, include susceptible and resistant genotypes to at least three of the four P. brachypodii isolates tested. This creates the opportunity to use B. distachyon/P. brachypodii as a model pathosystem. In one B. distachyon accession, heavy infection by the loose smut fungus Ustilago bromivora occurred. That pathogen could also serve as a model pathogen of Brachypodium.

Slender False Brome (<em>Brachypodium sylvaticum</em>, Poaceae), an Invasive Grass New to Ontario, Canada

Brachypodium sylvaticum, Slender False Brome, an invasive Eurasian grass, is reported for the first time in Ontario and eastern Canada from Grey County, southern Ontario. The only previous Canadian record is from Vancouver Island, British Columbia. The species is widespread in the U.S. Pacific Northwest, where it is spreading aggressively throughout much of western Oregon. In the eastern U.S.A., known populations are few and localized, although the species will likely spread.

Population regulation by enemies of the grass Brachypodium sylvaticum: demography in native and invaded ranges

The enemy-release hypothesis (ERH) states that species become more successful in their introduced range than in their native range because they leave behind natural enemies in their native range and are thus "released" from enemy pressures in their introduced range. The ERH is popularly cited to explain the invasive properties of many species and is the underpinning of biological control. We tested the prediction that plant populations are more strongly regulated by natural enemies (herbivores and pathogens) in their native range than in their introduced range with enemy-removal experiments using pesticides. These experiments were replicated at multiple sites in both the native and invaded ranges of the grass Brachypodium sylvaticum. In support of the ERH, enemies consistently regulated populations in the native range. There were more tillers and more seeds produced in treated vs. untreated plots in the native range, and few seedlings survived in the native range. Contrary to the ERH, total measured leaf damage was similar in both ranges, though the enemies that caused it differed. There was more damage by generalist mollusks and pathogens in the native range, and more damage by generalist insect herbivores in the invaded range. Demographic analysis showed that population growth rates were lower in the native range than in the invaded range, and that sexually produced seedlings constituted a smaller fraction of the total in the native range. Our removal experiment showed that enemies regulate plant populations in their native range and suggest that generalist enemies, not just specialists, are important for population regulation.

Cloning and Sequence Analysis of Actin Gene from Guzmania

As a house keeping gene, Actin was often used as inner control in quantitative and semiquantitative PCR tests to determine relative expressive amount of target genes. Based on EST monoclones of Actin gene obtained from Guzmania full length cDNA library, its full length cDNA sequence was obtained by Primer Walking sequencing. The gene, named for Goactin1 (GenBank accession No. HQ184438), consisted of 1 625 bp cDNA sequence, 1 131 bp ORF (open reading frame) which encoded a protein with 377 amino acids residues, and a putative protein which was 41.7 kD at estimated molecular weight, 5.31 at isoelectric point and had a ‘actin superfamily’conservative domain. The secondary structure of the protein was composed of random coil, alpha helix, extend strand and beta turn by SPOMA analysis. Furthermore, its tertiary structure was also build based on A chain of 2BTF. Through phylogenetic tree analysis, Goactin1 was gather to a same group with Actin protein in Solanum tuberosum , Gossypium hirsutum , Nicotiana tabacum , Brachypodium sylvaticum , and Arabidopsis thaliana .

Cloning and Sequence Analysis of Actin Gene from Guzmania

As a house keeping gene, Actin was often used as inner control in quantitative and semiquantitative PCR tests to determine relative expressive amount of target genes. Based on EST monoclones of Actin gene obtained from Guzmania full length cDNA library, its full length cDNA sequence was obtained by primer walking sequencing. The gene, named for Goactin1 (GenBank accession No. HQ184438), consisted of 1 625 bp cDNA sequence, 1 131 bp ORF (open reading frame) which encoded a protein with 377 amino acids residues, and a putative protein which was 41.7 kD at estimated molecular weight, 5.31 at isoelectric point and had a ‘actin superfamily’ conservative domain. The secondary structure of the protein was composed of random coil, alpha helix, extend strand and beta turn by SPOMA analysis. Furthermore, its tertiary structure was also build based on A chain of 2BTF. Through phylogenetic tree analysis, Goactin1 was gathered to the same group with Actin protein in Solanum tuberosum, Gossypium hirsutum, Nicotiana tabacum, Brachypodium sylvaticum, and Arabidopsis thaliana .

Synteny between Brachypodium distachyon and Hordeum vulgare as revealed by FISH

We investigated by fluorescence in situ hybridization (FISH) the synteny between Brachypodium distachyon with a small genome (1C = 320 Mb) and barley with a large genome (1C = 5,100 Mb) at the chromosome level. Reciprocal genomic in situ hybridization (GISH) between B. distachyon and barley labeled mainly 45S ribosomal DNA loci, indicating that most high copy DNA is weakly conserved between both grasses. Of 13 BAC clones with inserts from different B. distachyon chromosomes, only two belonging to chromosome 1 yielded hybridization signals on a barley metaphase chromosome (on 7HS and 7HL, respectively), confirming synteny between both chromosomes. FISH experiments to characterize the synteny of single-copy loci were performed. Two of four Brachypodium sylvaticum BACs spanning a 223-kb interval homologous to the region of barley that harbors a gibberellic-acid-insensitive semi-dwarfing gene, sdw3, hybridized specifically to a central position of B. distachyon chromosome 1 short arm but not to the homologous region of the barley genome. Repeat-free sequences PCR amplified from four non-overlapping barley BACs linked to the core of Sdw3 region yielded signals at distinct positions in the middle of barley chromosome arm 2HS. Together, these results (1) confirmed the synteny between B. distachyon chromosome 1 and barley chromosomes 2H and 7H at the cytological level, (2) indicated mid-arm position for the Sdw3 locus genetically mapped at the centromere of barley chromosome 2H, and (3) proved that the sdw3 core interval of < 100 kb in B. distachyon corresponds to a megabase-sized syntenic region in barley.

Fine mapping and syntenic integration of the semi-dwarfing gene sdw3 of barley

The barley mutant allele sdw3 confers a gibberellin-insensitive, semi-dwarf phenotype with potential for breeding of new semi-dwarfed barley cultivars. Towards map-based cloning, sdw3 was delimited by high-resolution genetic mapping to a 0.04cM interval in a "cold spot" of recombination of the proximal region of the short arm of barley chromosome 2H. Extensive synteny between the barley Sdw3 locus (Hvu_sdw3) and the orthologous regions (Osa_sdw3, Sbi_sdw3, Bsy_sdw3) of three other grass species (Oryza sativa, Sorghum bicolor, Brachypodium sylvaticum) allowed for efficient synteny-based marker saturation in the target interval. Comparative sequence analysis revealed colinearity for 23 out of the 38, 35, and 29 genes identified in Brachypodium, rice, and Sorghum, respectively. Markers co-segregating with Hvu_sdw3 were generated from two of these genes. Initial attempts at chromosome walking in barley were performed with seven orthologous gene probes which were delimiting physical distances of 223, 123, and 127kb in Brachypodium, rice, and Sorghum, respectively. Six non-overlapping small bacterial artificial chromosome (BAC) clone contigs (cumulative length of 670kb) were obtained, which indicated a considerably larger physical size of Hvu_sdw3. Low-pass sequencing of selected BAC clones from these barley contigs exhibited a substantially lower gene frequency per physical distance and the presence of additional non-colinear genes. Four candidate genes for sdw3 were identified within barley BAC sequences that either co-segregated with the gene sdw3 or were located adjacent to these co-segregating genes. Identification of genic sequences in the sdw3 context provides tools for marker-assisted selection. Eventual identification of the actual gene will contribute new information for a basic understanding of the mechanisms underlying growth regulation in barley.

Shifting dispersal modes at an expanding species’ range margin

While it is generally recognized that noncontiguous (long-distance) dispersal of small numbers of individuals is important for range expansion over large geographic areas, it is often assumed that colonization on more local scales proceeds by population expansion and diffusion dispersal (larger numbers of individuals colonizing adjacent sites). There are few empirical studies of dispersal modes at the front of expanding ranges, and very little information is available on dispersal dynamics at smaller geographic scales where we expect contiguous (diffusion) dispersal to be prevalent. We used highly polymorphic genetic markers to characterize dispersal modes at a local geographic scale for populations at the edge of the range of a newly invasive grass species (Brachypodium sylvaticum) that is undergoing rapid range expansion in the Pacific Northwest of North America. Comparisons of Bayesian clustering of populations, patterns of genetic diversity, and gametic disequilibrium indicate that new populations are colonized ahead of the invasion front by noncontiguous dispersal from source populations, with admixture occurring as populations age. This pattern of noncontiguous colonization was maintained even at a local scale. Absence of evidence for dispersal among adjacent pioneer sites at the edge of the expanding range of this species suggests that pioneer populations undergo an establishment phase during which they do not contribute emigrants for colonization of neighbouring sites. Our data indicate that dispersal modes change as the invasion matures: initial colonization processes appear to be dominated by noncontiguous dispersal from only a few sources, while contiguous dispersal may play a greater role once populations become established.

Delineating the structural, functional and evolutionary relationships of sucrose phosphate synthase gene family II in wheat and related grasses

BackgroundSucrose phosphate synthase (SPS) is an important component of the plant sucrose biosynthesis pathway. In the monocotyledonous Poaceae, five SPS genes have been identified. Here we present a detailed analysis of the wheat SPSII family in wheat. A set of homoeologue-specific primers was developed in order to permit both the detection of sequence variation, and the dissection of the individual contribution of each homoeologue to the global expression of SPSII.ResultsThe expression in bread wheat over the course of development of various sucrose biosynthesis genes monitored on an Affymetrix array showed that the SPS genes were regulated over time and space. SPSII homoeologue-specific assays were used to show that the three homoeologues contributed differentially to the global expression of SPSII. Genetic mapping placed the set of homoeoloci on the short arms of the homoeologous group 3 chromosomes. A resequencing of the A and B genome copies allowed the detection of four haplotypes at each locus. The 3B copy includes an unspliced intron. A comparison of the sequences of the wheat SPSII orthologues present in the diploid progenitors einkorn, goatgrass and Triticum speltoides, as well as in the more distantly related species barley, rice, sorghum and purple false brome demonstrated that intronic sequence was less well conserved than exonic. Comparative sequence and phylogenetic analysis of SPSII gene showed that false purple brome was more similar to Triticeae than to rice. Wheat - rice synteny was found to be perturbed at the SPS region.ConclusionThe homoeologue-specific assays will be suitable to derive associations between SPS functionality and key phenotypic traits. The amplicon sequences derived from the homoeologue-specific primers are informative regarding the evolution of SPSII in a polyploid context.

Context-dependent pattern and process: the distribution and competitive dynamics of an invasive grass, Brachypodium sylvaticum

Brachypodium sylvaticum, or false brome, a recent invader of North America, has spread rapidly following establishment in Oregon in 1939 and is now colonizing at least five US states. To understand how ecological processes and environmental context interact to facilitate invasion, we combined a GIS analysis of spatial patterns of invasion with a greenhouse competition experiment under two light and two nutrient levels, and a field competition-removal experiment. Brachypodium sylvaticum was concentrated along human-use corridors and in forests, where our experiments indicate it is a better competitor than co-occurring grasses. Forested areas near trails require the greatest focus for detection and control because the species’ dual propensities to establish and thrive in these locations may make them key source areas for further invasion. Our methodology demonstrates how understanding both the patterns and processes of invasion enables the prescription of context-specific remedial actions.

Characterization of the primary cell walls of seedlings of Brachypodium distachyon – A potential model plant for temperate grasses

The genome of Brachypodium distachyon, also known as purple false brome, was fully sequenced in 2008 largely in response to the demand for a model plant for temperate grasses. A comparative study of the primary cell walls of seedlings of B. distachyon, Hordeum vulgare and Triticum aestivum was carried out. The cell walls of the three species were characterized by similar relative levels of, and developmental changes in, hemicelluloses. The occurrence of (1,3;1,4)-β- d-glucans was correlated with phases of growth involving cell elongation. Expression profiling of the genes involved in (1,3;1,4)-β- d-glucan synthesis ( cellulose synthase-like F family ( CSLF), CSLH and a putative synthase gene CSLJ) did not show a transcriptional regulation that corresponded to the abundance of (1,3;1,4)-β- d-glucans. CSLF6 transcripts were similarly highly expressed in all three grasses, and were much more abundant than any of the other transcripts. The CSLH transcript was relatively abundant in B. distachyon but almost undetectable in the other species. The deposition of arabinoxylans increased steadily during seedling growth in all three grasses, but they became less substituted and more cross-linked into the wall matrix during cell maturation. Moreover, arabinoxylans in B. distachyon differed from the two other grasses in having a lower degree of arabinose substitution, a higher percentage of ferulic acid in form of dimers and a larger proportion of ester-linked p-coumaric acid.

Unravelling the effects of temperature, latitude and local environment on the reproduction of forest herbs

ABSTRACTAim To investigate the effect of temperature, latitude and local environment on the reproductive traits of widespread perennial forest herbs to better understand the potential impacts of rising temperatures on their population dynamics and colonization capacities.Location Six regions along a latitudinal gradient from France to Sweden.Methods Within each region, we collected data from three to five populations of up to six species. For each species, several variables were recorded in each region (temperature, latitude) and population (local abiotic and biotic environmental variables), and seed production and germination were estimated. Resource investment in reproduction (RIR) was quantified as seed number × seed mass, while germinable seed output (GSO) was expressed as seed number × germination percentage. We performed linear regression and mixed effect models to investigate the effects of temperature (growing degree hours), latitude and local abiotic and biotic environment on RIR and GSO.Results Temperature and latitude explained most of the variation in RIR and GSO for early flowering species with a northerly distribution range edge (Anemone nemorosa, Paris quadrifolia and Oxalis acetosella). Reproduction of the more southerly distributed species (Brachypodium sylvaticum, Circaea lutetiana and Primula elatior), in contrast, was independent of temperature/latitude. In the late summer species, B. sylvaticum and C. lutetiana, variation in RIR and GSO was best explained by local environmental variables, while none of the investigated variables appeared to be related to reproduction in P. elatior.Main conclusions We showed that reproduction of only two early flowering, northerly distributed species was related to temperature. This suggests that the potential reproductive response of forest herbs to climate warming partly depends on their phenology and distribution, but also that the response is to some extent species dependent. These findings should be taken into account when predictions about future shifts in distribution range are made.

Aphid feeding response and microsatellite-based genetic diversity among diploidBrachypodium distachyon(L.) Beauv accessions

False brome grass,Brachypodium distachyon(L.) Beauv, has been proposed as a new model species to bridge rice and temperate cereal crops for genomics research. However, much basic information for this species is still lacking. In this study, six diploidB. distachyon(2n = 2x = 10) accessions (Bd1-1, Bd2-3, Bd3-1, Bd18-1, Bd21 and BD29) were evaluated for their response to infestation by two cereal aphid pests of common wheat (Triticum aestivumL.): the greenbug,Schizaphis graminumRondani, and the Russian wheat aphid (RWA),Diuraphis noxiaMordvilko. Through database mining ofB. distachyonexpressed sequence tag (EST) and genomic DNA sequences, 160 EST- and 21 genomic microsatellite markers were developed and used to evaluate genetic diversity among theB. distachyonaccessions. All six accessions were resistant to RWA biotype RWA1 but showed distinct responses to feeding by greenbug biotypes C and E, as well as RWA2 RWAs. Although microsatellite-based genetic diversity among different accessions was generally low, Bd1-1 and BD29 were the most diverged from the other four lines. The genetic divergence was correlated with geographical distances between theBrachypodiumaccessions. Comparison of simple sequence repeat polymorphisms in three inbred lines (Bd2-3, Bd3-1 and Bd18-1) with their respective original parental lines revealed no effect of inbreeding on genetic diversity. Phylogenetic analysis suggested thatAegilops tauschii(Coss.) Schmal., the D genome donor of common wheat, was closer toB. distachyonthan to rice. The greenbug - B. distachyonsystem seems to be a model of choice for plant–aphid interaction studies in the grass genome.

Selectively eliminating and conserving exotic plants to save an endangered butterfly from local extinction

AbstractRare butterfly conservation requires understanding of butterfly interactions with the resource conditions that influence population growth. Exotic plant invasions can reduce butterfly population size and growth by displacing key resources, degrading habitat conditions and directly impacting fitness, but exotic plants may also be incorporated into native butterfly diets, rendering practicing conservation biologists a choice between exotic plant control and butterfly population persistence. Euphydryas editha taylori (Nymphalidae), a candidate endangered butterfly species in the Pacific Northwest of North America, switched from an unknown native larval host plant to become entirely dependent on an exotic larval host Plantago lanceolata in extant western Oregon populations. Furthermore, the last Oregon butterfly populations are surrounded by two exotic grasses, Brachypodium sylvaticum and Festuca arundinacea, both of which can dominate remnant native prairies and degrade native grassland structural conditions. When given a choice of habitat conditions, E. e. taylori oviposited on larval host plants surrounded by increasing abundance of short‐statured native bunchgrasses and adult nectar resources, indicating that females select egg‐laying sites based on habitat conditions rather than just host plant presence. Both larval and adult resources substantially diminished with increasing cover of exotic grasses and were nearly absent when B. sylvaticum and F. arundinacea dominated. Butterfly resource loss with increasing exotic grass cover, the documentation of contemporary subpopulation extinction, current historic site conditions and grass invasion history in the Willamette Valley suggest that mass E. e. taylori extinction in western Oregon by the late 1970s was due to B. sylvaticum and F. arundinacea invasion. To prevent the extinction of E. e. taylori, land managers must accept that the anthropogenically mediated host switch to P. lanceolata must be conserved and that reintroductions/augmentation with a potential native host plant species is unlikely to be effective because larval development is timed to P. lanceolata growth.

Seed bank composition and above-ground vegetation in response to grazing in sub-Mediterranean oak forests (NW Greece)

We investigate the persistent soil seed bank composition and its relation to the above-ground flora of grazed and non-grazed sub-Mediterranean deciduous oak forests of NW Greece. Twenty-eight taxa were recorded in the soil seed bank and 83 taxa (70 taxa in plots of seed bank sampling) in the above-ground vegetation. The dominant tree species and many woodland species found in the above-ground vegetation were absent from the soil seed bank. Similarity between the soil seed bank and the above-ground vegetation decreased with grazing, and grazing led to a decrease of species richness in above-ground vegetation and soil seed bank. Beta diversity of vegetation among grazed and among non-grazed plots did not differ, but was significantly higher between grazed and non-grazed areas. Beta diversity of the soil seed bank declined with grazing. When applying classification tree and logistic regression analyses, non-grazed forest sites are clearly differentiated by the presence of Phillyrea latifolia, Euphorbia amygdaloides and Brachypodium sylvaticum. PCA ordination of above-ground species composition reflected a gradient from sites grazed by ruminants to non-grazed sites, but no clear structure was detected in the seed bank.

Isolation and characterization of nine microsatellite markers for Brachypodium sylvaticum (Huds.) Beauv., a recently invasive grass species in Oregon

The patterns of genetic diversity caused by rapid range expansions following recent colonizations are best observed using highly polymorphic genetic markers. We characterized nine microsatellite markers for Brachypodium sylvaticum, a bunchgrass invasive in the Northwestern United States and native to Eurasia. Loci exhibited from two to 10 alleles, and generally had high F(IS) values. These loci will help identify sources of new populations in the region, and they will be useful for studying patterns of genetic diversity during rapid range expansions.

Evidence for multiple sources of invasion and intraspecific hybridization inBrachypodium sylvaticum(Hudson) Beauv. in North America

We compared the levels and distribution of genetic diversity in Eurasian and North American populations of Brachypodium sylvaticum (Huds.) Beauv. (false brome), a newly invasive perennial bunchgrass in western North America. Our goals were to identify source regions for invasive populations, determine the number of independent invasion events, and assess the possibility that postinvasion bottlenecks and hybridization have affected patterns of genetic diversity in the invaded range. We tested the hypothesis that this Eurasian grass was accidentally introduced into two areas in Oregon and one site in California by examining nuclear microsatellites and chloroplast haplotype variation in 23 introduced and 25 native populations. In the invaded range, there was significantly lower allelic richness (R(S)), observed heterozygosity (H(O)) and within-population gene diversity (H(S)), although a formal test failed to detect a significant genetic bottleneck. Most of the genetic variation existed among populations in the native range but within populations in the invaded range. All of the allelic variation in the invaded range could be explained based on alleles found in western European populations. The distribution of identified genetic clusters in the North American populations and the unique alleles associated with them is consistent with two historical introductions in Oregon and a separate introduction to California. Further analyses of population structure indicate that intraspecific hybridization among genotypes from geographically distinct regions of western Europe occurred following colonization in Oregon. The California populations, however, are more likely to be derived from one or perhaps several genetically similar regions in the native range. The emergence and spread of novel recombinant genotypes may be facilitating the rapid spread of this invasive species in Oregon.

Genotypes on the move: some things old and some things new shape the genetics of colonization during species invasions

When we set a species loose outside of its historical range, we create opportunities to test fundamental questions about how populations establish, adapt, disperse, and ultimately define range boundaries. A particularly controversial issue here is how genetic variation among and within populations contributes to the dynamics of species distributions. In this issue of Molecular Ecology, Rosenthal and colleagues (2008) seize an opportunity to examine how multiple introductions create genetically distinct establishment events and how these are incorporated into invasive spread. Their findings suggest that a particular recombinant lineage of Brachypodium sylvaticum may be responsible for most of the recent expansion of this invader, highlighting the potential importance of genetic novelty and historical context for colonization success.

Micro-colinearity between rice, Brachypodium, and Triticum monococcum at the wheat domestication locus Q

Brachypodium, a wild temperate grass with a small genome, was recently proposed as a new model organism for the large-genome grasses. In this study, we evaluated gene content and microcolinearity between diploid wheat (Triticum monococcum), Brachypodium sylvaticum, and rice at a local genomic region harboring the major wheat domestication gene Q. Gene density was much lower in T. monococcum (one per 41 kb) because of gene duplication and an abundance of transposable elements within intergenic regions as compared to B. sylvaticum (one per 14 kb) and rice (one per 10 kb). For the Q gene region, microcolinearity was more conserved between wheat and rice than between wheat and Brachypodium because B. sylvaticum contained two genes apparently not present within the orthologous regions of T. monococcum and rice. However, phylogenetic analysis of Q and leukotriene A-4 hydrolase-like gene orthologs, which were colinear among the three species, showed that Brachypodium is more closely related to wheat than rice, which agrees with previous studies. We conclude that Brachypodium will be a useful tool for gene discovery, comparative genomics, and the study of evolutionary relationships among the grasses but will not preclude the need to conduct large-scale genomics experiments in the Triticeae.