Salinity tolerance of wild barley Hordeum vulgare ssp. spontaneum

Salinity tolerance of 47 wild barley genotypes and six barley cultivars was evaluated under control and salinity stress (300 mM NaCl) conditions. Shoot and root dry weight (DW), plant height, membrane stability index (MSI), relative water content, survival rate, leaf malondialdehyde (MDA) and proline contents, root and leaf Na, K, Ca and K/Na ratio, and chlorophyll a fluorescence were measured. Salinity stress caused significant increase in the MDA, proline content, Na and Ca concentrations of the roots and leaves, but resulted in a decrease in the other traits. H. spontaneum genotypes were considerably less affected by the salinity than the genotypes of H. vulgare. Plant survivability was negatively correlated with the Na concentration (r =−.66) but positively correlated with the leaf K/Na ratio (r = .67) and MSI (r = .68). Tolerance mechanisms such as ion exclusion (Na) were likely to be present in the wild barley causing K/Na homeostasis as well as the much lower root and shoot Na, resulting in the higher survival rate.     

Inheritance of agronomic traits from the Chinese barley dwarfing gene donors 'Xiaoshan Lixiahuang' and 'Cangzhou Luodama'

The inheritance of agronomic traits from the barley dwarfing gene donors ‘Xiaoshan Lixiahuang’ and ‘Cangzhou Luodamai’ was studied. The results indicated that dwarf plants, six‐row and short spikes, dense spikelets and naked kernels, respectively, were controlled by one pair of recessive genes, but a toothed awn was determined by one pair of dominant genes in both barley cultivars. The genes for the six characters in ‘Xiaoshan Lixiahuang’ were allelic to those in ‘Cangzhou Luodamai’. Genetic linkage was found among the genes for plant height, spike length and spikelet density. They were located on the long arm of chromosome 3 (3HL) in the order: plant height, spikelet density, spike length. The genes for naked kernels, six‐row spikes and tooth awns were independent of each other, and carried on the long arms of chromosomes 1(7H), 2(H) and 7(5H), respectively. The dwarfing genes were the same as the gene uz in Japanese and Korean barley cultivars.     

Mapping genes for deep-seeding tolerance in barley

Deep-seeding tolerance, the emergence of seedlings from deep seeded conditions, is involved in stand establishment in semi-arid regions, where the soil surface is too dry for seed germination. Genes determining deep-seeding tolerance in barley were mapped using two doubled haploid populations derived from the following crosses: Harrington × TR306 (H/T)and Step toe × Morex (S/M). Significant quantitative trait loci (QTLs) for deep-seeding tolerance were found in each population. Two QTL sex plained 40% of the phenotypic variation in the H/T population and one QTL (S/M) 8% of the total phenotypic variance. Multiple QTLs accounting for coleoptile length and first internode length were detected in both populations. In the H/T population, there were coincident QTLs for deep-seeding tolerance, coleoptile length and first internode length on the long arm of chromosome 5H. These QTLs correspond with previously reported QTLs for abscisic acid and gibberellic acid response. QTL coincidence may be due to the pleiotropic effects of alleles at a single locus. This information may be useful for breeding programs manipulating morphological and physiological traits in order to develop varieties for semi-arid regions. This revised version was published online in August 2006 with corrections to the Cover Date.     

Inheritance of tolerance to zinc deficiency in barley

Barley (Hordeum vulgare L.) is often grown on alkaline zinc (Zn)‐deficient soils where reductions in yield and grain quality are frequently reported. Currently, the use of Zn‐based fertilizer along with Zn‐deficiency‐tolerant genotypes is considered the most thorough approach for cropping the Zn‐deficient soils; however, developing or breeding genotypes with higher Zn efficiency requires a good understanding of the inheritance of tolerance to Zn deficiency. This study was conducted to determine genetic control of this trait in barley. Two parental cultivars ('Skiff, moderately tolerant; and ‘Forrest’, sensitive), 185 F₂ plants, and 48 F₂‐derived F₃ families from this cross were screened to determine inheritance of tolerance to Zn deficiency using a visual score of deficiency symptoms. The segregation ratios observed indicated that greater tolerance to Zn deficiency in ‘Skiff compared with ‘Forrest’ at the seedling stage is controlled by a single gene with no dominance. The results also indicate that visual scores are useful for genetic analysis of tolerance to Zn deficiency.     

Inheritance of tolerance to barley yellow dwarf virus in oats

Summary Advanced generation random lines from crosses of tolerant x susceptible parents were studied to determine the inheritance of tolerance to barley yellow dwarf virus (BYDV) in oats Avena sativa L. Clintland 64, a susceptible oat cultivar, was crossed with the BYDV tolerant oat lines Otee, FF64/74, M921 and CI4492. Randomly selected lines were advanced to F5 or F6 by single seed descent and were tested for their reaction to BYDV at Palmerston North, New Zealand and Winnipeg, Manitoba and Ste-Foy, Quebec, Canada.The reactions of the lines to BYDV infection from each cross at the three test sites fall into a relatively continuous distribution. Two to four quantitatively inherited genes appear to contribute to the tolerance of the four tolerant oats. At Palmerston North, Clintland 64 expressed some tolerance to the virus.The correlation between the three sites was significant (P=0.01) for all crosses, ranging from 0.36 to 0.69, according to the particular cross considered. This correlation is sufficient to justify more international testing of oats for BYDV tolerance.Contribution Nos. 1163.     

Inheritance of resistance to Russian wheat aphid in barley

Summary The inheritance of resistance to Russian wheat aphid Diuraphis noxia (Mordvilko), in two resistant barleys, Hordeum vulgare L., ASE/2CM//B76BB and Gloria/Come, was studied in the field and in the greenhouse. The resistant genotypes were crossed with susceptible genotypes Esperanza and Shyri. Resistance reactions of F1, BC1, and F2 plants, and individual F2 plant derived F3 families indicated that resistance in each genotype was controlled by the same single dominant gene.     

Inheritance of resistance to Pyrenophora teres f. teres in spring barley

The inheritance of seedling resistance to a Swedish isolate of Pyrenophora teres f. teres was investigated in four resistance sources of spring barley. Accessions CI 2330, CI 5791, CI 5822 and CI 9779 were used as resistance sources, and the cultivar ‘Alexis’ was used as a susceptible parent in different crosses. From the disease reaction in the F₁, F₂ and F₃ generations it was concluded that the resistance was governed by the same two complementary genes in CI 5791, CI 822 and CI 9776. One of these genes was present in CI 2330. The first three cultivars were highly resistant to the isolate used in this investigation. These results, when combined with earlier studies, suggest that CI 5791, CI 5822 and CI 9776 may be of great value as sources of resistance to barley net blotch. Spearman's rank correlation between the disease reaction of F₂ plants and their F₃ progeny was highly significant (r = 0.75; P ≥ 0.001) It is suggested that selection in the F₂ generation is effective. In a backcross breeding scheme, single plant reactions in F₁ or F₂ need to be confirmed in later generations.     

大麦重组自交系群体籽粒总花色苷含量和千粒重QTL定位

以云南特有的紫色大麦紫光芒裸二棱和澳大利亚引进的黄色大麦Schooner构建的193个重组自交系为材料,对2013—2015年3年3个试验点的大麦籽粒总花色苷含量和千粒重进行相关性分析和QTL定位。大麦总花色苷含量和千粒重之间呈显著或极显著负相关。共检测到12个总花色苷含量QTL,分别位于1H、2H、4H、6H和7H染色体,贡献率为5.06%～23.86%; 8个千粒重QTL,分别位于2H、4H和7H染色体,贡献率为4.67%～42.32%。贡献率大于10%的QTL有10个,大于20%的有5个,最大的可达42.32%。其中至少2年2点重复检测到2个总花色苷含量QTL,分别位于2H Bmag0125–GBM1309和7H EBmatc0016–Bmag0206区间,可分别解释表型变异的13.66%～17.76%和13.07%～16.43%;3年3点重复检测到2个千粒重QTL,分别位于2HScssr03381–scssr07759和7H GBM1297-GBM1303区间,可分别解释表型变异的4.67%～14.55%和34.51%～42.32%,其加性作用方向均一致。控制总花色苷含量与千粒...     

Inheritance of plant height and allelism tests of the dwarfing genes in Chinese barley

In order to find new dwarfing genes, the inheritance of plant height in 25 Chinese barley dwarf accessions was studied and allelism tests carried out, not only between the dwarfing genes found but also with the known dwarfing genes uz, br, sdw and denso. The results showed that out of the 25 dwarf accessions, 20 were due to monogenic recessiveness and four to digenic recessiveness. Only the short plant character in ‘1974E’ was controlled by a recessive together with a dominant dwarfing gene. In the present study, seven recessive and one dominant new dwarfing genes were identified. Five recessive genes were found in the monogenic mutants ‘91G318’, ‘91D27’ and ‘93‐597’ and in the Tibetan monogenic dwarf landraces ‘Jia Jiu’ and ‘BQK’, respectively. The other two recessives were found in the Tibetan digenic dwarf landraces ‘ZLL’ and ‘ZLLQK’, and the one dominant gene in the digenic mutant ‘1974E’.     

Genetic regulation of growth and nutrient content under phosphorus deficiency in the wild barley introgression library S42IL

Phosphorus (P) is an important macronutrient required for plant growth and yield formation. Since decades, breeders aim to optimize P efficiency in crops. We studied a set of 47 wild barley (Hordeum vulgare ssp. spontaneum, Hsp) introgression lines (ILs) in hydroponic culture to identify quantitative trait loci (QTLs) improving growth and nutrient content under P deficiency. Applying a mixed model analysis, a total of 91 independent QTLs were located among 39 ILs, of which 64 QTLs displayed trait‐improving Hsp effects. For example, an unknown Hsp allele on barley chromosome 4H increased shoot dry weight under P deficiency in three overlapping ILs by 25.9%. Likewise, an Hsp allele on barley chromosome 6H increased root dry weight under P deficiency in two overlapping ILs by 27.6%. In total, 31 QTLs confirmed Hsp effects already identified in previous field and glasshouse experiments with the same ILs. We conclude that wild barley contains numerous trait‐improving QTL alleles, which are active under P deficiency. In future, the underlying genes can be subjected to cloning and, simultaneously, used in elite barley breeding.     

Inheritance and geographical distribution of phenol reaction-less varieties of barley

Summary The reaction of spikes and grains of barley to phenol was investigated using 8,849 cultivated and 349 wild accessions collected from the world. The pericarp and hull of the grain were stained dark brown by a 1% phenol solution and the reaction of awn was sharpest. Phenol reaction was controlled by a dominant gene, named Phr (phenol reaction) which was located on chromosome 2. All the wild strains of various Hordeum species showed a positive reaction to phenol indicating it was the prototype of the trait. Only 51 accessions of cultivated barley showed negative reaction to phenol. They were distributed along the so-called Silk-road and the type of variety was limited suggesting that it was a rather new mutation which occurred in the Middle East. Synteny of the chromosome region involving the phenol reaction gene in some gramineous plants was discussed.     

Transgenic barley by particle bombardment. Inheritance of the transferred gene and characteristics of transgenic barley plants

Summary Transgenic barley plants (Hordeum vulgare L. cv. Kymppi) were obtained by particle bombardment of various tissues. Immature embryos and microspore-derived cultures were bombarded with gold particles coated with plasmid DNA carrying the gene coding for neomycin phosphotransferase II (NPTII), together with plasmid DNA containing the gene for -glucuronidase (GUS).Bombarded immature embryos were grown to plants without selection and NPTII activity was screened in small plantlets. One plant proved to be transgenic (T₀). This chimeric plant passed the transferred nptII gene to its T₁ progeny. The presence of the nptII gene was demonstrated by the PCR technique and enzyme activity was analyzed by an NPTII gel assay. Four T₀ spikes and 15 T₁ offspring were transgenic. The integration and inheritance was confirmed by Southern blot hybridization. Transgenic T₂ and T₃ plants were produced by isolating embryos from green grains of transgenic T₁ and T₂ plants, respectively and growing them to plants. After selfing, the ratio of transgenic to non-transgenic T₂ offspring was shown to follow the rule of Mendelian inheritance. The general performance of transgenic plants was normal and no reduction in fertility was observed.Microspore-derived cultures were bombarded one and four weeks after microspore isolation. After bombardment, cultures were grown either with or without antibiotic selection (geneticin ^R or kanamycin). When cultures were grown without selection and regenerated plants were transferred to kanamycin selection in rooting phase, one out of a total of about 1500 plants survived. This plant both carried and expressed the transferred nptII gene. The integration was confirmed by Southern blot hybridization. This plant was not fertile.     

Genetic characterization of wild barley populations (Hordeum vulgare ssp. spontaneum) from Kazakhstan based on genome wide SNP analysis

The wild ancestral form of barley, Hordeum vulgare ssp. spontaneum, is a valuable source for gene enrichment of cultivated barley. The purpose of this work was to study the area of distribution as well as the extent and structure of genetic variation of wild barley populations grown in Kazakhstan. It was found that distribution of wild barley populations in Kazakhstan is restricted to the most southern province. A genome wide single nucleotide polymorphism (SNP) analysis was performed in order to study the level of the genetic diversity in 96 accessions representing 14 wild barley populations from Kazakhstan and 25 accessions from the Middle East which is the center of diversity of this subspecies. The oligonucleotide pooled assay was used to genotype 384 SNPs distributed throughout the genome. In total 233 polymorphic SNPs were selected for further statistical analysis. The level of genetic diversity of wild barley populations from Kazakhstan was predictably narrower (He = 0.19 ± 0.01) in comparison with wild barley samples from the Middle East (He = 0.29 ± 0.01). The results suggested that H. vulgare ssp. spontaneum populations in Kazakhstan probably represent a recent spread of a limited number of plants from the primary distribution area and might be well adapted to winter low temperature.     

Identification of novel alleles from wild barley for the improvement of alpha‐amylase and related malt quality traits

Germplasms consisting of 64 wild barley accessions (Hordeum vulgare ssp. spontaneum) were examined for polymorphisms in α‐amylase using both isoelectric focusing (IEF) and thermostability assays. Wide variation was found for the high pI α‐amylase with 20 IEF band patterns identified. Enzyme activity and thermostability assays showed large differences among α‐amylase isoenzymes. Two wild accessions Tel‐Shoket CPI 77146‐32 and Afiq CPI 77128‐41 showed superior enzyme activity and thermostability compared with commercial varieties such as ‘Baudin’, ‘Flagship’ or ‘Navigator’. The functionality of the Tel‐Shoket allele was validated in backcross lines with ‘Flagship’ as the recurrent parent. The Tel‐Shoket allele at the amy1 locus increased α‐amylase thermostability at 75°C by 8.4% and α‐amylase activity in kilned malt by 18.7%. The introgression of the wild allele also led to significant improvements in fermentability, hot water extract and viscosity. Gene sequencing showed that there are three single nucleotide polymorphisms in the Tel‐Shoket amy1 sequence, which can be used as diagnostic markers for the selection of this allele in breeding programmes.     

Inheritance of earliness in barley

The data collected by Johnson and Paul (1958) from five crosses for the study of the inheritance of earliness in barley have been re-analysed by following biometrical techniques as developed by Mather (1949).Earliness in barley was found to be controlled by polymeric genes. Two to five effective factors were estimated to be operating, affecting earliness in the various crosses.Presence of overdominance was observed in three of the five crosses, while in the remaining two crosses no dominance was noted.Transgressive segregation was observed in the two crosses, Frontier x Bonneville and Montcalm x Atsel. The cross, Montcalm x Atsel, may be a source for breeding a new strain which might be expected to mature earlier than the early parent, Atsel.University of Alberta Postdoctorate Research Fellow     

Variation in vegetative parameters related to the nitrogen economy of wild barley,Hordeum spontaneum,in Israel

Summary Hordeum spontaneum, the wild progenitor of cultivated barley, has previously been examined in various studies as a germplasm resource in breeding for grain protein content and related nutritional traits.The nitrogen content and dry weight of leaf and stem (stem plus sheath) at anthesis, and the final grain size and grain protein content were measured in 33 H. spontaneum and two H. vulgare genotypes. H. spontaneum was generally higher in nitrogen content of leaves and stems, but lower in dry weight at anthesis. Consistent with previous reports, the H. spontaneum genotypes were considerably higher in grain protein than the cultivars. There was wide variation between and within populations of H. spontaneum suggesting that for breeding purposes lines combining high vegetative nitrogen content, dry weight and grain protein content can be selected.Incumbent of the Seagram Chair for Plant Science     

Transgressive segregation in inter and intraspecific crosses of barley

Summary Six populations of F₂-derived lines of barley and their parents were evaluated for heading date, plant height, grain yield, bundle weight, and harvest index in a replicated experiment in the field. These data were used to estimate the minimum number of effective factor pairs segregating for each trait, the number of favorable factors contributed by each parent in a cross, and the frequencies and magnitudes of transgressive segregates.Heading date, plant height, and harvest index were controlled by three to four effective factor pairs, whereas grain yield and bundle weight were controlled by five or more.All three H. spontaneum strains used in our study contributed one or more useful genes for each of the traits, grain yield, heading date, plant height, bundle weight, and harvest index. Therefore, it seems that H. spontaneum can be a useful source of favorable genes for quantitative traits, especially for grain yield, which could be incorporated into barley varieties readily by backcrossing. Transgressive segregates for grain yield in the interspecific crosses may provide the basic materials for improving the productivity of cultivated barley varieties.Journal Paper No. J-9760 of the Iowa Agric. and Home Econ. Exp. Stn., Ames, IA 50011. Project 2227. Supported in part by a grant from the Science and Education Administration-Cooperative Research, United States Department of Agriculture.     

Inheritance of sensitivity to the insecticide diazinon in barley and the geographical distribution of sensitive varieties

Summary A total of 5,560 barley varieties collected from the world was tested for the sensitivity to an organophosphorous insecticide, diazinon. Among them, 708 (12.7%) varieties were sensitive to diazinon. The sensitive/insensitive reaction was clear when 1,000–2,000ppm diazinon solution was sprayed onto the young seedlings at low temperature. The sprayed leaves of the sensitive varieties wilted and failed to recover, while the succeeding leaves were normal and appeared to be unharmed although the vigor was reduced. Diazinon sensitivity was controlled by a dominant gene, named Diz, and it was located on chromosome 1 in an order of br-Diz-gl-5-n. The sensitive varieties were distributed mainly in the western part of the world, and none of the local varieties east of Nepal was sensitive to diazinon. Thus, Diz is a new and effective marker gene for studying the phylogeny of barley.     

Inheritance of resistance to powdery mildew (Erysiphe graminis f. sp. hordei) in eleven primitive barley varieties

The inheritance of the powdery mildew resistance of eleven primitive barley varieties was investigated. crosses with varieties with identified resistance genes revealed that at least three different genes are present in a group of six genotypes from Greece (Hor736, Hor847, Hor878, Hor1159, Hor1379 and Hor1873) and one from Turkey (Hor1188). One dominant gene is common to these seve genotypes and in the Greek accessions a second gene is present. The expression of this second gene was respectively dominant in the crosses with Hor736 and Hor1159, recessive in the crosses with Hor878 and Hor1873, and depended on the employed powdery mildew isolate in the crosses with Hor847 and Hor1379. The detected genes differ from the resistance genes of the crossing partners, viz. Ml-al2, Ml-(Ab), Ml-(CP) and Ml-(1402). The accessions from China (Hor824 and Hor4021) each possess two resistance genes which differ from Ml-a12, Ml-(La) and Ml-(CP). The major gene is common to both accessions and is either identical, allelic or closely linked to a gene in the variety Nigrate. The Columbian accession Hor1894 possesses one resistance gene linked to a resistance gene in Nigrate but this gene differs from the Ml-a locus. The variety Palestine (Hor3997) possesses two resistance genes of which one is allelic or closely linked to Ml-(at).