Monosomic and double monosomic substitutions of Hordeum bulbosum L. chromosomes into H. vulgare L.

Summary One of the aims of the interspecific crossing programme between Hordeum vulgare L. and H. bulbosum L. has been to introgress desirable genes into barley from the wild species. However, despite their close taxonomic relationship there have been few reports of achieving this objective using amphidiploid hybrids. In order to broaden the range of available hybrids, partially fertile triploids between H. vulgare (2n = 2x = 14) and H. bulbosum (2n = 4x = 28) were developed and crossed with H. vulgare as female parent. From 580 progeny which were screened, eight putative single monosomic chromosome substitution lines and one double monosomic substitution were identified by cytological analysis. These involved the substitution of H. vulgare chromosome 1 (two lines), 6 (four lines), 6L (one line), 7 (one line) and 1 + 4 (one line) by their respective H. bulbosum homoeologues. The H. bulbosum chromosome was frequently eliminated during plant development, but it was observed regularly in pollen mother cells of two lines. However, pairing between the H. bulbosum chromosome and its H. vulgare homoeologue was low. Several of the lines were more resistant than their H. vulgare parents to powdery mildew (Erysiphe graminis DC. f.sp. hordei Em. Marchai), net blotch (Drechslera teres Sacc.) and scald (Rhynchosporium secalis (Oudem.) Davis). Apart from their use in studying genome relationships, their value to plant breeders will depend on the ease of inducing translocations between the parental chromosomes.     

Genome relationships between Hordeum vulgare L. and H. bulbosum L.

Interrelationships between H. vulgare (2x=14) and H. bulbosum (2x=14; 4x=28) were estimated on the basis of the karyotypes and the pairing behaviour of the chromosomes in diploid, triploid and tetraploid hybrids obtained with the aid of embryo culture. — A comparison of the karyotypes of the two species revealed similarities as well as differences. It was concluded that at least 4 or more of the chromosomes were similar in morphology and probably closely related. — Diploid and tetraploid hybrids are rarely obtained and their chromosome numbers tend to be unstable whereas triploid hybrids (1 vulgare + 2 bulbosum genomes) were stable and relatively easy to produce. In the diploid hybrid only 40% of the meiotic cells contained 14 chromosomes while the numbers ranged from 7 to 16 in other cells. All hybrids exhibited pairing between the chromosomes of the two species. Diploid hybrids had a mean of 5.0 and a maximum of 7 bivalents per cell in those cells having 14 chromosomes. Triploid hybrids from crosses between 2x H. vulgare and 4x H. bulbosum exhibited a mean of 1.5 and a maximum of 5 trivalents per cell. In a hexaploid sector found following colchicine treatment of a triploid the mean frequencies of chromosome associations per cell were: 5.5_I+8.0_II+0.7_III+3.7_IV+0.3_V+0.4_VI. One unstable 27 chromosome hybrid obtained from crosses between the autotetraploid forms had a mean of 1.1 and a maximum of 4 quadrivalents per cell. The chromosome associations observed in these hybrids are consistent and are taken as evidence of homoeologous pairing between the chromosomes of the two species. Interspecific hybridization between these two species also reveals that chromosome stable hybrids are only obtained when the genomes are present in a ratio of 1 vulgare2 bulbosum. Based upon the results obtained, the possibility of transferring genetic characters from H. bulbosum into cultivated barley is discussed.     

Characterisation of progeny from backcrosses of triploid hybrids between Hordeum vulgare L. (2x) and H. bulbosum L (4x) to H. vulgare

Interspecific hybridisations between Hordeum vulgare L. (cultivated barley) and H. bulbosum L. (bulbous barley grass) have been carried out to transfer desirable traits, such as disease resistance, from the wild species into barley. In this paper we report the results of an extensive backcrossing programme of triploid hybrids (H. vulgare 2x x H. bulbosum 4x) to two cultivars of H. vulgare. Progenies were characterised cytologically and by restriction fragment length polymorphism analysis and comprised (1) haploid and diploid H. vulgare plants, (2) hybrids and aneuploids, (3) single and double monosomic substitutions of H. bulbosum chromosomes into H. vulgare and (4) chromosomal rearrangements and recombinants. Five out of the seven possible single monosomic chromosome substitutions have now been identified amongst backcross progeny and will be valuable for directed gene introgression and genome homoeology studies. The presence amongst progeny of 1 plant with an H. vulgare-H. bulbosum translocated chromosome and one recombinant indicates the value of fertile triploid hybrids for interspecific gene introgression.     

Analysis of chromosomal polymorphism in barley (Hordeum vulgare L. ssp. vulgare) and between H. vulgare and H. chilense using three-color fluorescence in situ hybridization (FISH)

The aim of the present work was to study chromosomal polymorphism within cultivated barley (Hordeum vulgare ssp. vulgare) using three-color fluorescence in situ hybridization (FISH). The physical distribution of the most frequently used, highly repetitive DNA sequences (GAA)₇ specific for pericentromeric heterochromatic regions, the ribosomal DNA clone pTa71, specific for the 45S rDNA, and the barley-specific telomere-associated sequence HvT01, was investigated to reveal genetic diversity in metaphase spreads of ten barley genotypes with diverse geographical origin, growth habit and row number. A wild relative of barley, Hordeum chilense was also studied in order to compare the polymorphism between and within Hordeum species. Significant differences in the hybridization patterns of all three DNA probes could be detected between the two related species, but only probes pTa71 and HvT01 showed variation in the intensity and/or position of hybridization sites among genotypes of H. vulgare ssp. vulgare. The extent of polymorphism was less than that earlier reported for molecular markers and was restricted to the long chromosome arms, with differences between the chromosomes. 1H and 3H proved to be the most variable chromosomes and 4H and 6H the most conserved.     

Genetic Control of Chromosome Elimination during Haploid Formation in Barley

Genetic control over chromosome stability in the interspecific hybrid embryos of Hordeum vulgare and H. bulbosum has been hypothesized to reside on specific chromosomes. In this study, crosses between the primary trisomic lines for the seven different H. vulgare chromosomes and tetraploid H. bulbosum revealed that both chromosomes 2 and 3 of H. vulgare were involved in the control of chromosome elimination. Subsequent crosses using the available monotelotrisomics for chromosomes 2 and 3 led to the conclusion that both arms of chromosome 2 and the short arm of chromosome 3 most likely contain major genetic factors.—From the results of this study and the genome balance observed in the interspecific crosses between H. vulgare and H. bulbosum at the diploid and tetraploid cytotypes, it appears that the factors causing the elimination of the bulbosum chromosomes are located on the H. vulgare chromosome. These factors are offset or balanced by factors on the H. bulbosum chromosomes which, when present in sufficient dosage, either neutralize the effects of the vulgare factors or are able to "protect" the bulbosum chromosomes.     

Karyotypes,nucleoli, and amphiplasty in hybrids between Hordeum vulgare L. and H. bulbosum L.

Chromosome measurements were carried out in Hordeum vulgare, H. bulbosum, and their diploid, triploid, and tetraploid hybrids. The chromosomes were classified by using relative values, and thus karyotypes were established. For comparison of these karyotypes both relative and absolute values were used. It was concluded that differential amphiplasty occurred, whereas neutral amphiplasty could not be demonstrated. In the hybrids the relative length of the parts of the chromosomes (long arm, short arm, satellite) was not changed in comparison with these lengths in the pure species. The karyotypes of both species had considerable similarities. From comparing the mean absolute genome lengths, it was, however, concluded that in the pure species, as well as in all hybrid types, the chromosomes of H. vulgare were longer than those of H. bulbosum. In the diploid and tetraploid hybrids the mean genome lengths were shorter than those in the pure species and the triploid hybrids. The differential amphiplasty was such that the secondary constriction of chromosome 6 of H. bulbosum, did not show up in the hybrids. This could be related to the suppression of nucleolar formation in the genome of H. bulbosum, because the maximum number of nucleoli in root tip cells equalled the number of satellite chromosomes. Finally it was found that the pattern of nucleolar fusion in diploid and triploid hybrids deviated from the expectation. The results were discussed in relation to chromosomal disturbances that occurred in the hybrid tissues and that resulted in elimination of chromosomes and other effects.     

The influence of parental genotype on the chromosome behaviour of Hordeum vulgare X H. bulbosum diploid hybrids

Summary The PMCs of 74 diploid hybrids involving ten H. vulgare varieties and three H. bulbosum lines were analysed at metaphase I and chromosome number and chiasma frequency recorded. There were differences between parental combinations and between plants within those combinations for both chromosome and chiasma number. It is suggested that these characters are controlled by both parents and that differences between plants within families reflect the heterozygosity of the H. bulbosum parents. Chromosomally stable, high pairing lines have been identified for use in a backcrossing programme to introduce H. bulbosum characters to the H. vulgare germplasm.     

The cytogenetics of a triploid Hordeum bulbosum and of some of its hybrid and trisomic derivatives

Summary The progeny from a cross between diploid H. vulgare and triploid H. bulbosum were mostly triploid (VBB) hybrids, the other progeny were haploid (V) barley (H. vulgare). From a cross between diploid and triploid H. bulbosum, four of the seven possible trisomic lines were isolated. The Giemsa banded karyotype of H. bulbosum was produced, and two of the lines were identified as trisomic for chromosomes 6 and 7. The cytology and transmission rates of the trisomics were examined.     

Transfer of a dominant gene for powdery mildew resistance and DNA from Hordeum bulbosum into cultivated barley (H. vulgare)

Summary In an attempt to transfer traits of agronomic importance from H. bulbosum into H. vulgare we carried out crosses between four diploid barley cultivars and a tetraploid H. bulbosum. Eleven viable triploid F₁ plants were produced by means of embryo rescue techniques. Meiotic pairing between H. vulgare and H. bulbosum chromosomes was evidenced by the formation of trivalents at a mean frequency of 1.3 with a maximum of five per cell. The resulting triploid hybrids were backcrossed to diploid barley, and nine DC₁ plants were obtained. Three of the BC₁ plants exhibited H. bulbosum DNA or disease resistance. A species specific 611-bp DNA probe, pSc119.2, located in telomeres of the H. bulbosum genome, clearly detected five H. bulbosum DNA fragments of about 2.1, 2.4, 3.4, 4.0 and 4.8 kb in size present in one of the BC₁ plants (BC₁-5) in BamHI-digésted genomic Southern blots. Plant BC₁-5 also contained a heterozygous chromosomal interchange involving chromosomes 3 and 4 as identified by N-banding. One of the two translocated chromosomes had the H. bulbosum sequence in the telomeric region as detected using in situ hybridization with pSc119.2. Two other BC₁ plants (BC₁-1 and BC₁-2) were resistant to the powdery mildew isolates to which the barley cultivars were susceptible. Seventy-nine BC₂ plants from plant BC₁-2 segregated 32 mildew resistant to 47 susceptible, which fits a ratio of 11, indicating that the transferred resistance was conditioned by a single dominant gene. Reciprocal crosses showed a tendency towards gametoselection that was relative to the resistance. Mildew resistant plant BC₁-2 also had a 1-kb H. bulbosum DNA fragment identified with a ten-base random primer using polymerase chain reaction (PCR). Forty-three BC₁ plants, randomly sampled from the 79 BC₁ plants, also segregated 2320 for the presence versus absence of this 1-kb H. bulbosum DNA fragment, thereby fitting a 11 ratio and indicating that the PCR product originated from a single locus. The 1-kb DNA fragment and disease resistance were independently inherited as detected by PCR analysis of bulked DNA from 17 resistant and 17 susceptible plants as well as by trait segregation in the 43 individual plants. The progenies produced could serve as an important resistant source in plant breeding. This is the first conclusive report of the stable transfer of disease resistance and DNA from H. bulbosum to H. vulgare.     

Chromosome elimination and chromosome pairing in tetraploid hybrids of Hordeum vulgare × H. bulbosum

Summary The C₀ tetraploid counterparts of diploid hybrids of Hordeum vulgare × H. bulbosum were meiotically analysed, and were found to be chromosomally less stable than the same genotypes had been as diploids. The 14 bulbosum chromosomes present in the tetraploid cytotypes were probably eliminated as pairs rather than randomly or one genome at the time. Development of the vulgare and bulbosum genomes was asynchronous in some hybrids, the bulbosum chromosomes appearing less advanced than the vulgare chromosomes in the same cell. This appeared to reduce pairing between bulbosum homologues and also suppressed homoeologous pairing.     

Chromosome instability in Hordeum vulgare x H. bulbosum hybrids

Chromosome number in Hordeum vulgare x H. bulbosum hybrids ranged between the haploid and diploid number but with peaks in frequency occurring at the 14 and 7 chromosome level. This was reflected in a gradual change from hybrid morphology to that of haploid H. vulgare. The rate of chromosome elimination differed significantly between hybrids, while within each hybrid, differences in mean chromosome number were recorded between and within individual tillers. An increase in temperature from 25–30° C caused a significant increase in the rate of elimination of H. bulbosum chromosomes.     

Mapping of powdery mildew resistance genes in a newly determined accession of Hordeum vulgare ssp. spontaneum

The accession PI466197 of wild barley (Hordeum vulgare ssp. spontaneum) with a newly identified resistance to powdery mildew caused by Blumeria graminis f.sp. hordei was studied with the aim to localise the genes determining resistance on a barley genetic map using DNA markers. Molecular analysis was performed in the F₂ population of the cross between the winter variety ‘Tiffany’ and the resistant accession PI466197, consisting of 113 plants. DNA markers, 17 simple sequence repeats (SSRs), four sequence-tagged sites (STSs) and one cleaved amplified polymorphic sequence (CAPS) marker developed from the Mla locus sequence were used for genetic mapping and a two-locus model of resistance was shown. One of the resistance genes originating from H. vulgare ssp. spontaneum PI466197 was localised between the markers RGH1aE1 and Bmac0213 on the short arm of chromosome 1H, which is the position consistent with the Mla locus. The other gene was proven to be highly significantly linked with GBMS247, Bmac0134 and MWG878 on the short arm of chromosome 2H. The flanking markers were Bmac0134 and MWG878, assigned 4 and 8 cM from the resistance gene, respectively. Until now, no gene conferring powdery mildew resistance originating from H. vulgare has been located on the short arm of barley chromosome 2H.     

The evolutionary history of sea barley (Hordeum marinum) revealed by comparative physical mapping of repetitive DNA

Background and Aims Hordeum marinum

is a species complex that includes the diploid subspecies marinum and both diploid and tetraploid forms of gussoneanum. Their relationships, the rank of the taxa and the origin of the polyploid forms remain points of debate. The present work reports a comparative karyotype analysis of six H. marinum accessions representing all taxa and cytotypes.

Methods

Karyotypes were determined by analysing the chromosomal distribution of several tandemly repeated sequences, including the Triticeae cloned probes pTa71, pTa794, pAs1 and pSc119·2 and the simple sequence repeats (SSRs) (AG)₁₀, (AAC)₅, (AAG)₅, (ACT)₅ and (ATC)₅.

Key Results

The identification of each chromosome pair in all subspecies and cytotypes is reported for the first time. Homologous relationships are also established. Wide karyotypic differences were detected within marinum accessions. Specific chromosomal markers characterized and differentiated the genomes of marinum and diploid gussoneanum. Two subgenomes were detected in the tetraploids. One of these had the same chromosome complement as diploid gussoneanum; the second subgenome, although similar to the chromosome complement of diploid H. marinum sensu lato, appeared to have no counterpart in the marinum accessions analysed here.

Conclusions

The tetraploid forms of gussoneanum appear to have come about through a cross between a diploid gussoneanum progenitor and a second, related—but unidentified—diploid ancestor. The results reveal the genome structure of the different H. marinum taxa and demonstrate the allopolyploid origin of the tetraploid forms of gussoneanum.     

Cytomolecular discrimination of the A<Superscript>m</Superscript> chromosomes of <Emphasis Type="Italic">Triticum monococcum</Emphasis> and the A chromosomes of <Emphasis Type="Italic">Triticum aestivum</Emphasis> using microsatellite DNA repeats

The cytomolecular discrimination of the A^m- and A-genome chromosomes facilitates the selection of wheat-Triticum monococcum introgression lines. Fluorescence in situ hybridisation (FISH) with the commonly used DNA probes Afa family, 18S rDNA and pSc119.2 showed that the more complex hybridisation pattern obtained in T. monococcum relative to bread wheat made it possible to differentiate the A^m and A chromosomes within homoeologous groups 1, 4 and 5. In order to provide additional chromosomal landmarks to discriminate the A^m and A chromosomes, the microsatellite repeats (GAA)_n, (CAG)_n, (CAC)_n, (AAC)_n, (AGG)_n and (ACT)_n were tested as FISH probes. These showed that T. monococcum chromosomes have fewer, generally weaker, simple sequence repeat (SSR) signals than the A-genome chromosomes of hexaploid wheat. A differential hybridisation pattern was observed on 6A^m and 6A chromosomes with all the SSR probes tested except for the (ACT)_n probe. The 2A^m and 2A chromosomes were differentiated by the signals given by the (GAA)_n, (CAG)_n and (AAC)_n repeats, while only (GAA)_n discriminated the chromosomes 3A^m and 3A. Chromosomes 7A^m and 7A could be differentiated by the lack of (GAA)_n and (AGG)_n signals on 7A. As potential landmarks for identifying the A^m chromosomes, SSR repeats will facilitate the introgression of T. monococcum chromatin into wheat.     

Characterization of fertility restoration in alloplasmic lines derived from hybridization of self-fertilized offspring of barley-wheat (Hordeum vulgare L. × Triticum aestivum L.) amphiploid with common wheat varieties Saratovskaya 29 and Pyrotrix 28

The problems of fertility restoration in the progeny of barley-wheat hybrids (H. vulgare × T. aestivum) are explained by incompatibility between the cytoplasm of cultivated barley and the nuclear genome of common wheat. Appropriate models for studying these problems are alloplasmic lines that combine the cytoplasm of barley and the nuclear genome of wheat. In this work, the differences of fertility restoration in alloplasmic common wheat lines (H. vulgare)-T. aestivum were studied depending on the influence of wheat varieties Saratovskaya 29 (Sar29) and Pyrotrix 28 (Pyr28) used to produce these lines. The alloplasmic lines were created using hybrids between the 48-chromosome offspring (Amph₁) of the barley-wheat amphiploid H. vulgare (ya-319) × T. aestivum (Sar29) and these wheat varieties. Backcrossing of the Amph₁ (2n = 48) × Sar29 hybrid with the wheat variety Sar29 resulted in the complete sterility in the (H. vulgare)-Sar29 line, which suggests the incompatibility of the nuclear genome of the common wheat variety Sar29 with the cytoplasm of H. vulgare. Crossing of Amph₁ (2n = 48) with Pyr28 resulted in the restoration of self-fertility in the hybrid with 2n = 44. In the alloplasmic lines (2n = 42) formed based on plants of the self-fertilized generations of this hybrid, the barley chromosomes were eliminated, and recombination between the nuclear genomes of the parental wheat varieties Sar29 and Pyr28 took place. Alloplasmic recombinant lines (H. vulgare)-T. aestivum with different levels of fertility were isolated. As was shown by the SSR analysis, differences in the fertility between these lines are determined by differences in the content of the genetic material from the wheat varieties Sar29 and Pyr28. The complete restoration of fertility in these alloplasmic recombinant lines is accompanied by the formation of a nuclear genome in which the genetic material of Pyr28 significantly prevails. The conclusion is made that the common wheat variety Pyrotrix 28 is a carrier of a gene (or genes), which determines the restoration of common wheat fertility on the cytoplasm of cultivated barley.     

The transfer of a powdery mildew resistance gene from Hordeum bulbosum L to barley (H. vulgare L.) chromosome 2 (2I)

Hordeum bulbosum L. is a source of disease resistance genes that would be worthwhile transferring to barley (H. vulgare L.). To achieve this objective, selfed seed from a tetraploid H. vulgare x H. bulbosum hybrid was irradiated. Subsequently, a powdery mildew-resistant selection of barley phenotype (81882/83) was identified among field-grown progeny. Using molecular analyses, we have established that the H. bulbosum DNA containing the powdery mildew resistance gene had been introgressed into 81882/83 and is located on chromosome 2 (2I). Resistant plants have been backcrossed to barley to remove the adverse effects of a linked factor conditioning triploid seed formation, but there remains an association between powdery mildew resistance and non-pathogenic necrotic leaf blotching. The dominant resistance gene is allelic to a gene transferred from H. bulbosum by co-workers in Germany, but non-allelic to all other known powdery mildew resistance genes in barley. We propose Mlhb as a gene symbol for this resistance.     

In silico mining of EST-SSRs in <Emphasis Type="Italic">Arachis hypogaea</Emphasis> L. and their utilization for genetic structure and diversity analysis in cultivars/breeding lines in Odisha,India

A total of 26,685 unutilized public domain expressed sequence tags (ESTs) of Arachis hypogaea L. were analyzed to give a total of 4442 EST-SSRs, in which 517 ESTs contained more than one simple sequence repeat (SSR). Of these EST-SSRs, 2542 were mononucleotide repeats (MNRs), 803 were dinucleotide repeats (DNRs), 1043 were trinucleotide repeats (TNRs), 40 were tetranucleotide repeats (TtNRs), six were pentanucleotide repeats (PNRs) and eight were hexanucleotide repeats (HNRs). Out of these 4442 EST-SSRs, only 1160 were found to be successful in non-redundant primer design; 1060 were simple SSRs, while the remaining 100 were compound forms. Among all the motifs, MNRs were abundant, followed by TNRs and DNRs. The AAG/CTT motif was the most abundant (~33 %) TNR, while AG/CT was the most abundant DNR. For redundancy and novelty, a stringent criterion deploying three different strategies was used and a total of 782 novel EST-SSRs were added to the public domain of peanut. These novel EST-SSR markers will be useful for qualitative and quantitative trait mapping, marker-assisted selection and genetic diversity studies in cultivated peanut as well as related Arachis species. A subset of 30 novel EST-SSRs was further randomly selected for validation and genotyping studies with eight well-known cultivars and 32 advanced breeding lines (ADBX lines, ADBY lines and ADBZ lines) from Odisha state, India. The number of polymorphic markers among accessions of A. hypogaea was low; however, a set of informative EST-SSR markers detected considerable levels of genetic variability in peanut cultivars and uncharacterized breeding lines collected from Odisha. The 30 newly developed EST-SSRs from Arachis spp. showed ~97 % amplification in Cicer arientinum and 93 % in pigeon pea. Thus, the EST-SSRs developed in this study will be a very useful asset for genetic analysis, comparative genome mapping, population genetic structure and phylogenetic inferences among wild and allied species of Arachis.     

The time rate and mechanism of chromosome elimination in Hordeum hybrids

Seed development at 20±1° C in continuous light was studied during the first 5 days after pollination in diploid Hordeum vulgare, diploid H. bulbosum and the cross, H. vulgare x H. bulbosum, where H. bulbosum chromosomes were eliminated. Developing seeds were fixed and stained at known intervals after pollination and the embryo sac contents dissected out for cytological examination. — In all cases, the pattern of development was similar to that previously described for the Triticeae. After intraspecific pollination, the rate of endosperm and embryo development was significantly faster in H. vulgare than in H. bulbosum. In hybrid tissues, the rate was intermediate, but often much nearer to that of H. vulgare at first. Elimination of H. bulbosum chromosomes occurred only during endosperm and embryo mitoses. Usually, 0–3 chromosomes were lost at any one division but up to 7 were lost at some. Elimination, which occurred as early as zygotic anaphase, was nearly or quite complete in all dividing cells in both embryo and endosperm after 5 days. The mean number of chromosomes lost per nucleus per nuclear cycle was low at first but rose rapidly and stayed high for about a day in each tissue before falling quickly. The rate of elimination in each tissue was maximal when that tissue first synthesized significant amounts of new cytoplasm (day 2 after pollination in the endosperm and day 3 in the embryo). At mitosis, chromosomes being eliminated differed from others only in failing to congress at metaphase or to reach a pole at anaphase or both. — It is noted that in several widely different examples where either haploids are produced when only hybrids are expected, or where chromosomes of one species are preferentially eliminated from hybrid cells, nucleolar activity was suppressed in chromosomes of the genome which was selectively or preferentially eliminated. Consequently, it is suggested that chromosome elimination in Hordeum hybrids may be caused by a disturbed control of protein metablism in hybrid seeds and perhaps H. bulbosum chromosomes are selectively eliminated because they are less efficient than H. vulgare chromosomes at forming normal attachments to spindle protein.     

QTL Analysis in Recombinant Chromosome Substitution Lines and Doubled Haploid Lines Derived from a Cross between Hordeum vulgare ssp. vulgare and Hordeum vulgare ssp. spontaneum

Recombinant chromosome substitution lines (RCSLs) were developed in BC₃ generation to introduce segments of a wild barley strain ‘H602’ (Hordeum vulgare ssp. spontaneum) into a barley cultivar ‘Haruna Nijo’ (H. vulgare ssp. vulgare) genetic background. One hundred thirty four RCSLs were genotyped by 25 SSR and 60 EST markers, which were localized on a linkage map of doubled haploid lines (DHLs) derived from the same cross combination. Graphical genotyping revealed that the observed average substitution ratio of H602 segment (12.9%) agreed with the expected substitution ratio (12.5%), and a minimum set of 19 RCSLs represented the entire H602 genome. Phenotypes of five qualitative and nine quantitative traits were scored in both the RCSLs and DHLs. Five qualitative traits were localized as morphological markers on the linkage map of the DHLs, and these molecular markers were aligned on the respective chromosomal regions in the RCSLs. Simple and composite interval mapping procedures detected a total of 18 and 24 QTLs for nine qualitative traits on the RCSLs and DHLs, respectively. Several QTLs were localized at coincident or very close regions on both linkage maps. In spite of general inferior agronomic performances in wild barley, several H602 QTL alleles showed agronomically positive effects. These RCSLs should contribute to substitution of favorable alleles from wild barley into cultivated barley. These RCSLs are also available as sources of near isogenic lines, with which we can apply advanced genetic analysis methods such as isolation of QTLs and detection of epistatic interactions among QTLs.