Allelic Diversity of Hrd A and Hrd B Hordein-Coding Loci in Wild (Hordeum spontaneum C. Koch) and Cultivated (Hordeum vulgare L.) Barley from Israel and Palestine

Russian Journal of Genetics - Polymorphism of hordeins encoded by the Hrd A and Hrd B loci was studied using starch gel electrophoresis in 13 barley landrace accessions and in 31 wild barley...     

Studies on G-Banding Karyotype in Barley (Hordeum vulgare)

G-banding karyotypes of three cultivars in barley were analyzed. Multiple closely adjacent G-bands were able to be observed in each early metaphase or metaphase chromosome treatted by an ASG method. The more concentrated the chromosome, the less was the number of G-bands during mitosis. The position of band distribution, staining degree and band numbers between homologous chromosomes were basically identical. Chromosome pairing for karyotype analysis could be carried out more accurately. G-banding patterns of different chromosome pairs were not the same, they could be used as the markers to distinguish one from another chromosome pair. During the same mitotic stage the banding patterns including number, relative position and staining degree of the bands between different cultivars were basically the same, but they had differences in the size and staining degree of some bands near centromeres. G-banding technique and G-banding of metaphase chromosomes were discussed.     

On the origin and domestication history of Barley (Hordeum vulgare)

Remains of barley (Hordeum vulgare) grains found at archaeological sites in the Fertile Crescent indicate that about 10,000 years ago the crop was domesticated there from its wild relative Hordeum spontaneum. The domestication history of barley is revisited based on the assumptions that DNA markers effectively measure genetic distances and that wild populations are genetically different and they have not undergone significant change since domestication. The monophyletic nature of barley domestication is demonstrated based on allelic frequencies at 400 AFLP polymorphic loci studied in 317 wild and 57 cultivated lines. The wild populations from Israel-Jordan are molecularly more similar than are any others to the cultivated gene pool. The results provided support for the hypothesis that the Israel-Jordan area is the region in which barley was brought into culture. Moreover, the diagnostic allele I of the homeobox gene BKn-3, rarely but almost exclusively found in Israel H. spontaneum, is pervasive in western landraces and modern cultivated varieties. In landraces from the Himalayas and India, the BKn-3 allele IIIa prevails, indicating that an allelic substitution has taken place during the migration of barley from the Near East to South Asia. Thus, the Himalayas can be considered a region of domesticated barley diversification.     

Further Characterization of Calmodulin from the Monocotyledon Barley (Hordeum vulgare)

We report here that calmodulin isolated from the monocotyledon barley is indistinguishable by a variety of criteria from calmodulin isolated from the dicotyledon spinach. In contrast to previous reports, we find that barley (Hordeum vulgare) calmodulin has an amino acid composition similar to that of vertebrate and spinach calmodulins, including the presence of a single trimethyllysinyl residue, and that barley calmodulin quantitatively activates cyclic nucleotide phosphodiesterase. Furthermore, spinach and barley calmodulins are similar in terms of tryptic peptide maps and immunoreactivity with various antisera that differ in their molecular specificities for calmodulins. Limited amino acid sequence analysis demonstrates that the region around the single histidinyl and trimethyllysinyl residues is identical among barley, spinach, and vertebrate calmodulins and that barley calmodulin, like spinach calmodulin, has a novel glutamine residue at position 96. We conclude that calmodulin is highly conserved among higher plants and that detailed sequence analysis is required before significant differences, if any, can be assigned to barley or other higher plant calmodulins. These studies suggest that calmodulin's fundamental importance to the eukaryotic cell may have been established prior to the evolutionary emergence of higher plants.     

Jasmonate-induced Changes in Flavonoid Metabolism in Barley (Hordeum vulgare) Leaves

The effects of jasmonic acid (JA) on secondary metabolism in barley (Hordeum vulgare L.) were investigated. A reversed-phase HPLC analysis revealed that the amount of a particular compound increased in excised barley leaf segments that had been treated with JA. This compound was purified and identified as 6´´´-feruloylsaponarin (1) by spectroscopic analyses and alkaline hydrolysis. A related compound, 6´´´-sinapoylsaponarin (2), was also found to accumulate in excised leaves independently of the JA treatment. The accumulation of these compounds was accompanied by a decrease in the saponarin (3) content. [8,9-¹³C]p-Coumaric acid and [2,3,4,5,6-²H]L-phenylalanine were effectively incorporated into the hydroxycinnamoyl moieties in 1 and 2, while the degree of incorporation of the labeled precursors into the saponarin part was small. These findings indicate that the hydroxycinnamoyl moieties of 1 and 2 are synthesized de novo from phenylalanine via the phenylpropanoid pathway, and that the saponarin part is mainly provided by the constitutive pool of 3.     

西藏青稞4个B组醇溶蛋白基因的克隆和特征

从两份西藏青稞材料中分离克隆出4个B组醇溶蛋白基因（BH1—BH4）,DNA测序结果表明：它们均包含完整的开放阅读框。推断的氨基酸序列与先前报道的大麦B组醇溶蛋白具有相同的蛋白质基本结构。系统分析表明：它们推断的氨基酸序列与栽培大麦中的B组醇溶蛋白具有较高的相关性,与野生大麦和山羊草属的醇溶谷蛋白相似性较低。并且,在4个基因BH1—BH4中,BH1与先前报道的B组醇溶蛋白基因有较低的序列相似性,因此我们对BH1基因进行了原核表达,含该基因的表达载体在大肠杆菌中表达出相对分子质量为28．15kDa并以包涵体形式存在的蛋白,进一步对其在青稞谷粒品质改良中的潜在价值进行了探讨。     

Chlorophyll Fluorescence as a Possible Tool for Salinity Tolerance Screening in Barley (Hordeum vulgare L.)

The application of chlorophyll fluorescence measurements to screening barley (Hordeum vulgare L.) genotypes for salinity tolerance has been investigated. Excised barley leaves were cut under water and incubated with the cut end immersed in water or in a 100-mM NaCl solution, either in the dark or in high light. Changes in rapid fluorescence kinetics occurred in excised barley leaves exposed to the saline solution only when the incubation was carried out in the presence of high light. Fluorescence changes consisted of decreases in the variable to maximum fluorescence ratio and in increases in the relative proportion of variable fluorescence leading to point I in the Kautsky fluorescence induction curve. These relative increases in fluorescence at point I appeared to arise from a delayed plastoquinone reoxidation in the dark, since they disappeared after short, far-red illumination, which is known to excite photosystem I preferentially. We show that a significant correlation existed between some fluorescence parameters, measured after a combined salt and high-light treatment, and other independent measurements of salinity tolerance. These results suggest that chlorophyll fluorescence, and especially the relative fluorescence at point I in the Kautsky fluorescence induction curve, could be used for the screening of barley genotypes for salinity tolerance.     

Comparative Leaf Epidermal Anatomy of Mutants of Barley (Hordeum vulgare L. 'Himalaya') which Differ in Leaf Length

We wished to determine the nature of differences in epidermalcell numbers and dimensions between leaves of different lengthin mutants of barley (Hordeum vulgare L. ‘Himalaya’).Three comparisons were made: leaf one (L1)vs. leaf four (L4);wild typevs. nine dwarf mutants and wild typevs. a slender mutant.L1 was shorter than L4, and for most lines this was associatedwith a change in epidermal cell number for the blade, and inboth cell number and length for the sheath. Compared to wildtype, the smaller leaves of dwarf plants generally had shorterand fewer cells in both blade and sheath. The blade of slenderplants was the same length (L1) or longer (L4) than wild type,while the sheath was longer than that of wild type for bothL1 and L4. Slender plants had longer but fewer cells than thewild type along the blade of L1, and shorter but more cellsfor the blade of L4. In the sheath, slender plants had longerand more (L1) or fewer (L4) cells than did the wild type. ForL1, variation in blade width amongst the barley lines was associatedwith a change in file width and file number. For L4, blade widthvaried only with file number, except for slender plants wherenarrow blades were associated with reduced file width. Hencethere was no consistent correlation between changes in cellsize or cell (or file) number with changes in leaf length orwidth. Differences depended on the leaf (L1vs. L4), leaf part(bladevs. sheath), and the nature of the mutation (dwarfvs.slender). Barley (Hordeum vulgare L. ‘Himalaya’); leaf epidermis; dwarf mutant; slender mutant     

Effects of Mannitol Pretreatment on Androgenesis of Barley (Hordeum vulgare L.)

The effects of mannitol pretreatment on androgenesis of barley were systematically studied in comparison with that of cold pretreatment and control. The results showed that mannitol pretreatment could significantly increase the frequency of pollen survival reaching 19.0% on the eighth day, while in cold pretreatment and control they were 8.4% and 6.6 %, respectively. Mannitol pretreatment could also improve the quality of pollen and inhibit starch production from microspore, which were quite advantageous to microspore division and development. The developing period was shortened 2--3 days as compared with cold pretreatment and control. The major developmental pathways of androgenesis after mannitol pretreatment were the equal division (B pathway). In addition, the majority of microspore nuclei were diploids. On the contrary, the major microspores pretreated with low temperature had fewer chromosomes than with mannitol pretreatment, the microspore nuclei were haploids.     

A Single Locus Is Responsible for Salinity Tolerance in a Chinese Landrace Barley (Hordeum vulgare L.)

Introduction

Salinity and waterlogging are two major abiotic stresses severely limiting barley production. The lack of a reliable screening method makes it very hard to improve the tolerance through breeding programs.

Methods

This work used 188 DH lines from a cross between a Chinese landrace variety, TX9425 (waterlogging and salinity tolerant), and a Japanese malting barley, Naso Nijo (waterlogging and salinity sensitive), to identify QTLs associated with the tolerance.

Results

Four QTLs were found for waterlogging tolerance. The salinity tolerance was evaluated with both a hydroponic system and in potting mixture. In the trial with potting mixture, only one major QTL was identified to associate with salinity tolerance. This QTL explained nearly 50% of the phenotypic variation, which makes it possible for further fine mapping and cloning of the gene. This QTL was also identified in the hydroponic experiment for different salt-related traits. The position of this QTL was located at a similar position to one of the major QTLs for waterlogging tolerance, indicating the possibility of similar mechanisms controlling both waterlogging and salinity tolerance.

Conclusion

The markers associated with the QTL provided a unique opportunity in breeding programs for selection of salinity and waterlogging tolerance.     

Comparative salt tolerance of two wild Hordeum species (H. maritimum with. and H. murinum L.) from the coast of Tuscany (Italy)

ABSTRACT

The differences in salt tolerance between Hordeum maritimum and H. murinum were studied. Seeds were collected at horn maturity from wild populations growing respectively near the Orbetello Lagoon and S. Piero a Grado (Tuscany, Italy) and were used in germination and growth tests at increasing salinity (NaCl) levels. H. maritimum was confirmed to be a true halophyte as compared to H. murinum, which exhibited germination behavior typical of many wild glycophytes. The higher salt sensitivity of H. murinum compared to H. maritimum was also shown by its shoot length values, which decreased only in H. murinum, albeit in 100 mM NaCl treatment. The higher degree of salt tolerance of H. maritimum is further demonstrated by the Na : K ratio. H. maritimum can accumulate a greater amount of sodium than potassium in both roots and shoots, even in the absence of salt treatment. However, in NaCl solutions H. maritimum showed a higher Na : K ratio for shoots — an index of better uptake and translocation of sodium to leaves — as has been demonstrated for many halophyte includers. These results thus help to enhance knowledge on wild relatives of barley, whose potential contribution to genetic improvement in salinity tolerance has previously not been thoroughly explored.     

Regulation of Fructan Metabolism in Leaves of Barley (Hordeum vulgare L. cv Gerbel)

Excised primary leaf blades of barley (Hordeum vulgare L. cv Gerbel) rapidly synthesized large quantities of fructan in the light and, upon transfer to the dark, they rapidly degraded it again. In the course of such a light/dark cycle the activities of sucrose-sucrose-fructosyltransferase (SST), fructan hydrolase, and invertase were measured in cell-free extracts of the blades. SST activity increased 20-fold within 24 hours in the light and disappeared again upon transfer to the dark during a similar period of time. Cycloheximide inhibited the increase of SST activity in the light indicating de novo synthesis. The loss of SST activity in the dark, however, was unaffected by cycloheximide. No SST activity appeared in the light if photosynthesis was inhibited by lowering the CO₂ concentration in the atmosphere. However, SST activity and fructan synthesis were induced even in the dark and at a low CO₂ concentration when the leaf blades were immersed in a solution of sucrose. Several other sugars, maltose and fructose in particular, had the same effect. Trehalose induced SST activity but no fructan synthesis occurred. The activities of fructan hydrolase and invertase changed little during the light/dark cycle. It is suggested that the control of SST activity in conjunction with the supply of photosynthates plays a key role in the regulation of fructan metabolism.     

Natural H Currents Traverse Growing Roots and Root Hairs of Barley (Hordeum vulgare L.)

With the aid of an extracellular vibrating electrode, natural electric fields were detected and measured in the medium near growing roots and root hairs of barley seedlings. An exploration of these fields indicates that both the root as a whole, as well as individual root hairs, drive large steady currents through themselves. Current consistently enters both the main elongation zone of the root as well as the growing tips of elongating root hairs; it leaves the surface of the root beneath the root hairs. These currents enter with a density of about 2 microamperes per square centimeter, leave with a density of about 0.5 to 1 microampere per square centimeter, and total about 30 nanoamperes.     

不同预处理方法对大麦花药-花粉培养的影响

研究了甘露醇预处理的适应性以及pH值对甘露醇预处理效果的影响;并首次将山梨醇预处理应用到大麦花药培养中,获得理想的实验结果。第一,采用甘露醇预处理, 17种材料平均愈伤组织诱导率为20.67块/花药,绿苗产量为2.46株/花药。第二,甘露醇预处理溶液的pH值不同,其预处理的效果也不同。其中,愈伤组织诱导率和绿苗产量均以pH5.6最高。第三,不同浓度(0.1-0.5mol/L)的山梨醇预处理3天绿苗产量差异不显著;但同一浓度(0.3mol/L)山梨醇预处理不同天数(1-7天)绿苗产量差异极显著,以3天处理效果最好,绿苗产量是对照的51.2倍。     

Effects of Far-red Light on the Labelling of Acyl Lipids during the Greening of Barley (Hordeum vulgare)

Etiolated Hordeum vulgare (barley) Plants were greened underwhite light or far-red (> 700 nm) light. Exposure to far-redlight inhibited chlorophyll synthesis (especially chlorophyllb) and the development of photosystem II which were seen whengreening took place under white light. Primary leaves were detachedand the labelling of their acyl lipids from [¹⁴C]acetate wasstudied under white light or far-red light illumination. Greeningwith far-red light caused a reduction in the radiolabellingof polyunsaturated fatty acids and diacylgalactosylglycerol.Total fatty acid labelling rates were unaffected. Phosphatidylethanolamine,which was normally poorly labelled, accounted for up to 15 percent of the total radioactivity in acyl moieties of lipids inleaves greened with far-red light. The results are discussedin connection with the role that acyl lipids may play in normalthylakoid structure and function. Hordeum vulgare, barley, acyl lipids, white light, far-red light, chloroplasts, thylakoids     

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.     

Quantitative Trait Loci for Salinity Tolerance Identified under Drained and Waterlogged Conditions and Their Association with Flowering Time in Barley (Hordeum vulgare. L)

Introduction

Salinity is one of the major abiotic stresses affecting crop production via adverse effects of osmotic stress, specific ion toxicity, and stress-related nutritional disorders. Detrimental effects of salinity are also often exacerbated by low oxygen availability when plants are grown under waterlogged conditions. Developing salinity-tolerant varieties is critical to overcome these problems, and molecular marker assisted selection can make breeding programs more effective.

Methods

In this study, a double haploid (DH) population consisting of 175 lines, derived from a cross between a Chinese barley variety Yangsimai 1 (YSM1) and an Australian malting barley variety Gairdner, was used to construct a high density molecular map which contained more than 8,000 Diversity Arrays Technology (DArT) markers and single nucleotide polymorphism (SNP) markers. Salinity tolerance of parental and DH lines was evaluated under drained (SalinityD) and waterlogged (SalinityW) conditions at two different sowing times.

Results

Three quantitative trait loci (QTL) located on chromosome 1H, single QTL located on chromosomes 1H, 2H, 4H, 5H and 7H, were identified to be responsible for salinity tolerance under different environments. Waterlogging stress, daylight length and temperature showed significant effects on barley salinity tolerance. The QTL for salinity tolerance mapped on chromosomes 4H and 7H, QSlwd.YG.4H, QSlwd.YG.7H and QSlww.YG.7H were only identified in winter trials, while the QTL on chromosome 2H QSlsd.YG.2H and QSlsw.YG.2H were only detected in summer trials. Genes associated with flowering time were found to pose significant effects on the salinity QTL mapped on chromosomes 2H and 5H in summer trials. Given the fact that the QTL for salinity tolerance QSlsd.YG.1H and QSlww.YG.1H-1 reported here have never been considered in the literature, this warrants further investigation and evaluation for suitability to be used in breeding programs.     

Salinity tolerance in different cultivars of barley (Hordeum vulgare L.)

Seven barley(Hordeum vulgäre L.) cultivars tested varied greatly in their responses to root medium salinity (electrical conductivity of 3, 5, 10, 15 and 20 dS nr^-1)-lant growth was relatively more adversely affected than seed germination. Dry/fresh mass ratio increased at higher salinity levels in all barley cultivars indicating reduced water uptake. Higher K/Na ratio in plant shoots compared to that in the root medium solution indicated selective uptake of K that seems to be among processes involved in tolerance of cultivars to salinity stress.