Chinese Barley Research Articles

Barley protein function as growth inhibitor in Saccharomyces cerevisiae

The extracted toxic barley protein showed different protein content depending on the barley strain and demonstrated an inhibitory effect on the growth of yeast and glucose consumption. Chinese barley Danpi-2 had the highest concentration of toxic protein of all the types barley tested. When the concentration of proteins was increased to 32 μg/ml, the inhibition ratio also went up by 50%. The SDS-PAGE electrophoresis pattern showed that the protein was stable and tolerant at the temperature of 100°C.

Herbicidal Activity of Rotation Crop Residues on Weeds and Selectivity to Crops

Allelopathic activity of rotation crop residues to common weeds and selectivity of crops were studied for developing an alternative weed control strategy in upland organic farming. All rotation crop residues with various ratios suppressed weed growth, but the growth of crop species stimulated a little when those were grown with the mixture of rotation crop residues except a few crop species. Among the rotation crop residues used in this study hairy vetch was the most effective, followed by Chinese milkvetch, barley and rye in suppression of weed growth. The 90:10 (crop:soil, v/v) treatments incorporation rate of crop residues such as hairy vetch and Chinese milkvetch suppressed completely the growth of all weed species tested in this study. The effect of crop residues on suppression of weed growth reduced to 90% when the incorporation rates decreased to 60% [60:40 (crop:soil, v/v). It was noticed that broadleaf weed species were more susceptible to rotation crop residues than grass weed species. In the influence of crop residues on the crop growth, no growth inhibition was found in red pepper, lettuce and perllia at any incorporation rates, but tomato, cucumber and corn were slightly inhibited in a few cases at their highest incorporation levels. This study demonstrated that rotation crop residues especially hairy vetch and Chinese milkvetch have high herbicidal effects against weeds without inhibiting the growth of crop species.

Resistance to Fusarium head Blight and Deoxynivalenol Accumulation in Chinese Barley

Abstract Fusarium head blight (FHB) caused by Fusarium graminearum Schwabe is a devastating barley disease world‐wide, causing significant yield losses and contaminating cereal products with mycotoxins. Barley grain contaminated with deoxynivalenol (DON) is associated with gushing and may be rejected by the malting and brewing industry. Genetically inherited resistance is the most effective option for the control of the disease. A total of 266 barley cultivars and breeding lines originating from China were evaluated for FHB resistance and concentration of DON in grain. Plants were inoculated with isolates of F. graminearum under field conditions by injecting conidia into a single spikelet of each spike. FHB symptoms were evaluated by visual inspection, and DON content was analysed by HPLC. Significant differences in FHB ratings and DON levels were observed among cultivars. Visual symptoms of FHB varied from 4.88 to 71.75% of infected spikelets 21 days after inoculation and from 7.86 to 113.33 area under the disease progress curve units (AUDPC). Twenty‐seven lines were more resistant to FHB than the control resistant cultivar Zhedar 2 and with fewer than 12% infected spikelets. Twenty‐one of the above lines originated from the area in the mid to low valley of Yangtze River, where FHB epidemics are frequent. DON levels ranged from 0.05 to 24.39 mg/kg among the tested barley lines. Correlation coefficients were significant between FHB symptom ratings and DON levels. However, there was no significant correlation between symptom rating and plant height and no significant correlation between symptom rating and heading date.

Molecular analysis of cultivated naked barley (Hordeum vulgare L.) from Qinghai-Tibet Plateau in China using SSR markers

Naked barley is widely planted in Qinghai-Tibet Plateau in China and is essential for the daily life of Tibetans in those regions. In this study, the genetic diversity of 64 cultivated naked barley accessions from Qinghai-Tibet Plateau in China was analyzed using 30 mapped SSRs linked with the important traits of barley improvement. A total of 132 alleles were identified at 22 polymorphic SSR loci, with the number of each locus ranging from 2 to 15, the polymorphism information content (PIC) values ranging from 0.16 to 0.91, and with an average of 0.65. Of the selected SSRs, 13 SSR markers with high PIC value were highly efficient for the genetic analysis of Chinese barley. The accessions were divided into five main groups by cluster analysis and could be differentiated from each other. The genetic diversity in the Tibet accessions was slightly higher than in the Sichuan accessions. It is found that there were specific genes linked with the collecting sites. These results indicate the cultivated naked barley from Qinghai-Tibet Plateau in China are highly polymorphic and could be considered as an important resource bank for cultivated naked barley breeding in the future.

Comparative Study of Activity and Heat Stability of Limit Dextrinase in 16 Barley Cultivars

ABSTRACTWe conducted a comprehensive study of 15 cultivars of Chinese barley and one cultivar of European barley to examine and compare the activity and heat stability of limit dextrinase (LD) among them. Our results revealed that the enzymatic activity of LD drops dramatically at incubation temperatures >65°C, indicating that 65°C is the point of incubation temperature sensitivity for this enzyme. Compared with the European barley cultivar Triumph, the levels of enzymatic activity and heat stability of LD in most Chinese barley cultivars included in this study were low, except for Jipi 2 and 92001, which were nearly equal to Triumph. We also found that the activity and heat stability of LD were strongly influenced by the genotype and growth environment of the cultivar, which suggests that genetic manipulation and optimal cultivation conditions may be useful in producing high‐quality barley for the brewing industry.

Analysis of dwarfing genes in Zhepi 1 and Aizao 3: Two dwarfing gene donors in barley breeding in China

Inheritance of plant height was studied in Zhepi 1 and Aizao 3, two dwarfing gene donors used in barley (Hordeum vulgare L.) breeding programs in China. With direct cross and para-backcross methods, allelism tests were conducted for Zhepi 1 and Aizo 3 with barley entries carrying either brh 1, uzu 1, sdw1, or six new dwarfing genes recently identified in Chinese barley accessions. Plant height in both Zhepi 1 and Aizao 3 was controlled by the same recessive dwarfing gene. The dwarfing gene carried by both of these cultivars is different from the three known and the six new dwarfing genes. Based on the results of this study, only two dwarfing genes have predominantly been used in barley breeding in China since 1950. Key words: Hordeum vulgare, dwarf source, dwarfing gene

Effects of Extraction Solvent Mixtures on Antioxidant Activity Evaluation and Their Extraction Capacity and Selectivity for Free Phenolic Compounds in Barley (HordeumvulgareL.)

Four kinds of solvent extracts from three Chinese barley varieties (Ken-3, KA4B, and Gan-3) were used to examine the effects of extraction solvent mixtures on antioxidant activity evaluation and their extraction capacity and selectivity for free phenolic compounds in barley through free radical scavenging activity, reducing power and metal chelating activity, and individual and total phenolic contents. Results showed that extraction solvent mixtures had significant impacts on antioxidant activity estimation, as well as different extraction capacity and selectivity for free phenolic compounds in barley. The highest DPPH* and ABTS*+ scavenging activities and reducing power were found in 80% acetone extracts, whereas the strongest *OH scavenging activity, O2*- scavenging activity, and metal chelating activity were found in 80% ethanol, 80% methanol, and water extracts, respectively. Additionally, 80% acetone showed the highest extraction capacity for (+)-catechin and ferulic, caffeic, vanillic, and p-coumaric acids, 80% methanol for (-)-epicatechin and syringic acid, and water for protocatechuic and gallic acids. Furthermore, correlations analysis revealed that TPC, reducing power, DPPH* and ABTS*+ scavenging activities were well positively correlated with each other (p < 0.01). Thus, for routine screening of barley varieties with higher antioxidant activity, 80% acetone was recommended to extract free phenolic compounds from barley. DPPH* scavenging activity and ABTS*+ scavenging activity or reducing power could be used to assess barley antioxidant activity.

Powdery Mildew Resistance in a Collection of Chinese Barley Varieties

One hundred and forty-seven Chinese barley varieties maintained at the Gene Bank of the National Barley Improvement Centre, Zhejiang, and 84 progenies from these varieties were tested at the seedling stage for their reaction to 32 selected pathotypes of Blumeria graminis f. sp. hordei. Eighteen resistance spectra were identified comprising single or combined resistances from eight known (Ml(Bw), Ml(Ch), Mla7, Mla8, Mla9, Mla13, MlaRu4 and Mlg) and six unknown resistance genes. The most frequent gene was Ml(Bw), which was found in 69 varieties and previously detected in only a few European winter barley varieties. The genes Mla8 and Ml(Ch) were also often present, but other resistance genes were rare. After inoculation, considerably fewer pathogen colonies were observed in ‘Aiganqi’ and one line of ‘Tong5’. Twenty varieties were composed of lines with different resistance genes. China is likely to be a region of origin of the genes Ml(Bw), Mla7, as well as three unknown genes found in original landraces and perhaps another three unknown genes detected in cultivars bred in China. The resistances of varieties from the Zhejiang province and those originating from 11 other Chinese provinces were quite different. Unfortunately, none of the varieties are promising sources of resistance to powdery mildew and China does not seem to be a region suitable for identifying such sources.

Assessing Genetic Diversity of Chinese Cultivated Barley by STS Markers

To assess the genetic diversity among China’s cultivated barley, sequence tagged site (STS) marker analysis was carried out to characterize 109 morphologically distinctive accessions originating from five Chinese eco-geographical zones. Fourteen polymorphic STS markers representing at least one in each chromosome were chosen for the analysis. The 14 STS markers revealed a total of 47 alleles, with an average of 3.36 alleles per locus (range 2–8). The proportion of polymorphic loci per population averaged 0.84 (range 0.71–1.00); the mean gene diversity averaged 0.39 (range 0.28–0.49). The means of P and He were highest in the Yangtze reaches and Southern zone (P = 1.00; He = 0.46) and lowest (P = 0.71 He = 0.28) in the Yellow river reaches zone. The STS diversity in different zones is quite different from the morphology diversity. The STS variation was partitioned into 17% among the zone and 83% within the zone. Both cluster and principal coordinate analyses clearly separated the accessions into a dispersed group (mostly two-rowed barley with a lower mean GS value) and a concentrated group (mostly six-rowed barley with a higher mean GS value) according to the spike characteristic with only a few exceptions. The accessions from the Qinghai-Tibet plateau formed a distinctive subgroup and can be distinguished from the concentrated group. The role of Tibet in the origin and evolution of cultivated barley has been discussed.

Sampling Strategies for Composing a Core Collection of Cultivated Barley (Hordeum vulgare s. Iat.) Collected in China

Using 96 accessions of Chinese barley landraces with reliable passport data, alternative methods for composing a core collection have been compared. The relative success of the different methods was assessed by counting the number of isozymic variants in the resulting core collections; the larger the number of alleles in the core collection, the more successful the method. Clustering on the basis of the location of the collection site was compared with clustering on the basis of qualitative and quantitative morphological characteristics. The collection site data proved to be the best basis for clustering, followed by the qualitative descriptive data, i.e., row number, presence of awns or hoods, and kernel covering. Clustering based on quantitative data, i.e., heading date and plant height, did not improve sampling efficiency. The optimal number of clusters obtained using the collection site data was eight, and corresponds to the number of geographical regions where the germplasm was collected. Alternatives for allocating the accessions to the groups after clustering were also compared, but seemed to have little effect; in general, proportional and logarithmic allocation scored better than constant representation, but this was not always the case.

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

AbstractIn 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’.

Mapping of Quantitative Trait Loci Conferring Resistance to Barley Yellow Mosaic Virus in a Chinese Barley Landrace Mokusekko 3.

A Chinese six-rowed barley landrace, Mokusekko 3, exhibits a wide resistance spectrum to all the barley yellow mosaic virus strains in Japan (BaYMV-I, -II, -III) and in Europe (BaYMV-1, -2) as well as to barley mild mosaic virus (BaMMV). To identify the genetic basis for the resistance to BaYMV, a cross between a Japanese malting barley cultivar Ko A (susceptible) and Mokusekko 3 was made to generate F2 and F3 populations. The reaction of the F2-derived F3 lines to BaYMV was investigated in a field infected with BaYMV (-I or both -I and -II) during two growing seasons, 1996 and 1997. BaYMV disease severity of the F2 individuals was quantitatively expressed as the percentage of the susceptible seedlings within the F3 line. For the linkage analysis along the whole chromosome, a map of the barley genome consisting of 100 markers was used. The map covers 1291cM with an average density of 14cM. The interval mapping method was used to identify the quantitative trait loci (QTLs) for resistance to BaYMV. A new QTL for resistance to the BaYMV was located in the terminal region of chromosome 7HS, explaining 20-25% of the phenotypic variance, in addition to those in the terminal region of chromosome 3HL and centromeric region of chromosome 4H. The three QTLs accounted for 55-57% of the total phenotypic variance. The location of the QTLs on chromosomes 4H and 3HL corresponded well to that of rym1 and rym5 which were previously mapped for resistance to BaYMV in Mokusekko 3 using morphological and isozyme markers. Based on these results, the effect of pyramiding of these resistance factors into modern barley cultivars by marker-assisted selection is was examined.

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.

Genetic analysis of disease resistance to all strains of BaYMV in a Chinese barley landrace, Mokusekko 3

A Chinese landrace of barley, Mokusekko 3, is unique in being completely resistant against all strains of barley yellow mosaic virus (BaYMV). The present investigation revealed that the resistance of Mokusekko 3 is governed by two recessive genes. As one of the resistance genes was known to be tightly linked with alleles at the Est complex locus, consisting of the Est1, Est2 and Est4 loci for esterase isozymes, each of the resistance genes could be separated by means of marker-assisted selection using an isozyme allelic combination as a marker. One of the resistance genes, ym1, is linked to K (hooded lemma) and gl3 (glossy leaf 3) with recombination values of 25.3% and 9.7% respectively, and these three genes are located in the order K-gl3-ym1 on chromosome 4. Another newly designated resistance gene, ym5, is linked to alleles at the Est complex locus and cu2 (curly growth 2), with recombination values of 1.9% and 19.5% respectively, in the order cu2-Est-ym5 from proximal to distal on the long arm of chromosome 3. The complete resistance of Mokusekko 3 is caused by combining two resistance genes, ym1 and ym5. However, almost all the “resistant” cultivars derived from crosses with Mokusekko 3 are susceptible to the recently detected strain BaYMV-III in Japan, since they contain only one resistance gene, ym5. Marker-assisted selection to combine resistance genes into a cultivar is discussed for the breeding of stabilizing resistance to BaYMV.

Identification of a barley chromosomal interchange using N-banding and in situ hybridization techniques

The combination of N-banding and in situ hybridization was used to illustrate the rapid identification of the chromosomes involved in a newly formed chromosomal interchange (reciprocal translocation) in barley. The plant heterozygous for the interchange was derived from the backcross of 'Su Pie', a two-rowed Chinese winter barley cultivar (2n = 2x = 14), with pollen from a triploid interspecific F1 hybrid (2n = 3x = 21) obtained from the cross of 'Su Pie' × tetraploid Hordeum bulbosum accession GBC141 (2n = 4x = 28). Pollen mother cells of the interchanged plant exhibited one quadrivalent and five bivalents in 97.8% of cells. Partial sterility of florets was observed in spikes obtained from self-pollination and the plants morphologically resembled barley. Barley chromosomes were readily identified by N-banding from root-tip cells with one band missing from the short arm of one of the pair of chromosome 4. N-banding of metaphase I of meiosis revealed that chromosomes 1, 2, and 5 were not involved in the interchange. In situ hybridization with a rDNA probe showed that chromosomes 6 and 7 were paired as bivalents. In conclusion, chromosomes 3 and 4 are involved in the interchange with the breakpoint in the short arm of chromosome 4 between the two proximal N-bands. The use of chromosome-specific DNA probes for chromosome identification using in situ hybridization is proposed.Key words: barley, chromosomal interchange, N-banding, in situ hybridization, rDNA.