Breeding progress,genotypic and environmental variation and correlation of quality traits in malting barley in German official variety trials between 1983 and 2015

Key message

Evaluation of breeding progress for spring barley varieties in Germany showed that both grain yield and malting quality were considerably improved during the last 33 years, and that genetic effects of protein concentration and malting traits were not associated.

Abstract

Based on historical data, this study aimed to investigate yield potential and malting quality of 187 varieties tested and released in German registration trials to evaluate the value for cultivation and use (VCU) during 1983–2015, and to quantify the environmental variability and the association among traits. We used mixed linear models with multiple linear regression terms to dissect genetic and non-genetic trend components. Grain yield increased by 43% (23.4 dt ha^?1) in VCU trials and 35% (14.0 dt ha^?1) on-farm relative to 1983. All yield components contributed significantly. Malting quality was also considerably improved by 2.3% for extract content up to 25.1% for friability, relative to 1983, nearly completely due to new varieties. Total variability of individual traits was very different between traits (2.4–24.4% relative to 1983). The relative influence of genotypes on total variation was low for grain yield and its components, whereas it was considerably larger for other traits. We found remarkable differences between phenotypic and genetic correlation coefficients for grain yield and protein concentration with malting traits. The observed positive phenotypic relation between grain yield and malting quality can be attributed to a shift of selection and environmental effects, but genetic correlations showed a negative association. Genetic effects of protein concentration and malting quality were not correlated indicating that both were not genetically linked. Considerable yield progress and improvement of malting quality were achieved despite of their weak to moderate negative genetic dependence.

     

Genetic analysis of grain and malt quality in an elite barley population

Quantitative trait loci (QTLs) associated with grain weight, grain width, kernel hardness and malting quality were mapped in a doubled haploid population derived from two elite Australian malting barley varieties, Navigator and Admiral. A total of 30 QTLs for grain weight, grain width and kernel hardness were identified in three environments, and 63 QTLs were identified for ten malting quality traits in two environments. Three malting quality traits, namely β-amylase, diastatic power and apparent attenuation limit, were mainly controlled by a QTL linked to the Bmy1 gene at the distal end of chromosome 4H encoding a β-amylase enzyme. Six other malting quality traits, namely α-amylase, soluble protein, Kolbach index, free amino-acid nitrogen, wort β-glucan and viscosity, had coincident QTL clustered on chromosomes 1HS, 4HS, 7HS and 7HL, which demonstrated the interdependence of these traits. There was a strong association between these malt quality QTL clusters on chromosomes 1HS and 7HL and the major QTL for kernel hardness, suggesting that the use of this trait to enable early selection for malting quality in breeding programs would be feasible. In contrast, the majority of QTLs for hot-water extract were not coincident with those identified for other malt quality traits, which suggested differences in the mechanism controlling this trait. Novel QTLs have been identified for kernel hardness on chromosomes 2HL and 7HL, hot-water extract on 7HL and wort β-glucan on 6HL, and the resulting markers may be useful for marker-assisted selection in breeding programs.     

Consequences of Wheat Breeding on Nitrogen and Phosphorus Yield, Grain Nitrogen and Phosphorus Concentration and Associated Traits

Several studies have analysed the effects of wheat breedingon dry matter accumulation and partitioning, but little hasbeen done to understand the effects on nutrient economies. Theobjective of this study was to identify the changes producedby wheat breeding in the economy of nitrogen and phosphorusunder field conditions. Two experiments were carried out withseven genotypes (including a commercial hybrid) representingdifferent eras of plant breeding. Wheat breeding has increased grain nitrogen and phosphorus yieldbut total absorbed nutrients have not shown any trend duringthis century. The main attribute closely related to the increasein grain nitrogen and phosphorus yields was their harvest indices.The higher nutrient partitioning in the newer cultivars wasassociated with lower grain nitrogen and phosphorus concentrationsin their grains. Therefore, there was a negative effect of geneticimprovement in grain nitrogen and phosphorus concentrations.The main cause for the decreased concentration of these nutrientsin the grains of the modern cultivars appeared to be a dilutionby an even more increased dry matter partitioning. It is suggestedthat future breeding should be aimed to select for higher nitrogenuptake as a way to increase the level of this nutrient in grain.Copyright1995, 1999 Academic Press Triticum aestivum L., wheat breeding, genetic improvement, nitrogen, phosphorus, wheat, grain nitrogen concentration, grain phosphorus concentration     

Growth, yield and grain quality of barley (Hordeum vulgare L.) in response to nitrogen uptake. I. A low cost, controlled nutrient supply system

This paper describes the development of an inexpensive, perlite culture system with recirculating nutrient solutions which required simple maintenance and provided aerial conditions approximating those of a crop stand. A range of repeatable nitrogen experiments provided sufficient plant material for sequential, destructive harvests, grown under the same climatic conditions and protected from rainfall by a polythene tunnel. A study of the effects of nitrogen uptake on development, growth, grain yield, and quality was done in two contrasting cultivars of malting barley. Two nitrogen treatments were imposed, High N where nitrogen was supplied to plant demand and Low N where nitrogen supply was restricted to one-third of that demand. The development of the controlled nutrient supply system is described and the possible improvements and test performance according to three criteria is discussed: (1) the uniformity of growth and nitrogen uptake within a treatment bed, (2) the ability to achieve the desired nitrogen uptakes (3 : 1, High N:Low N) and (3) that the stand of plants behaves as a crop rather than a collection of isolated or semi-isolated plants are discussed. This third criterion was evaluated using Greenwood's (1982) definition of optimal nitrogen uptake for maximal growth and compared with the results obtained in the High N treatments.     

花后干旱或渍水逆境下氮素对小麦籽粒产量和品质的影响

 池栽试验条件下,设置渍水、干旱和对照3个水分处理,每个水分处理下设置两个施氮水平 ,研究了花后渍水或干旱逆境下氮素营养对两个不同类型小麦（Triticum aestivum） 品种籽粒产量和品质性状的影响。结果表明,与对照相比,花后渍水或干旱处理显著降低了小麦的千粒重、穗粒数和籽粒产量。在适宜水分和干旱条件下,增施氮肥增加了小麦籽粒产量,而在渍水条件下,增施氮肥降低了产量。干旱处理提高了蛋白质含量,干、湿面 筋含量,沉降值和降落值;而渍水处理则降低了小麦籽粒蛋白质含量和干、湿面筋含量。同 一水分处理下,增施氮肥提高了蛋白质含量,谷蛋白/醇溶蛋白比,支链淀粉含量和支/直链淀粉比。在小麦籽粒主要品质性状上存在显著的水氮互作效应,且水分、氮肥及水氮互作效 应对小麦籽粒产量和品质的影响因品种的不同而异。     

QTL analysis of malting quality in barley based on the doubled-haploid progeny of two elite North American varieties representing different germplasm groups

Characterization of the determinants of economically important phenotypes showing complex inheritance should lead to the more effective use of genetic resources. This study was conducted to determine the number, genome location and effects of QTLs determining malting quality in the two North American barley quality standards. Using a doubled-haploid population of 140 lines from the cross of Harrington×Morex, malting quality phenotype data sets from eight environments, and a 107-marker linkage map, QTL analyses were performed using simple interval mapping and simplified composite interval mapping procedures. Seventeen QTLs were associated with seven grain and malting quality traits (percentage of plump kernels, test weight, grain protein percentage, soluble/total protein ratio, α-amylase activity, diastatic power and malt-extract percentage). QTLs for multiple traits were coincident. The loci controlling inflorescence type [vrs1 on chromosome 2(2H) and int-c on chromosome 4(4H)] were coincident with QTLs affecting all traits except malt-extract percentage. The largest effect QTLs, for the percentage of plump kernels, test weight protein percentage, S/T ratio and diastatic power, were coincident with the vrs1 locus. QTL analyses were conducted separately for each sub-population (six-rowed and two-rowed). Eleven new QTLs were detected in the subpopulations. There were significant interactions between the vrs1 and int-c loci for grain-protein percentage and S/T protein ratio. Results suggest that this mating of two different germplasm groups caused a disruption of the balance of traits. Information on the number, position and effects of QTLs determining components of malting quality may be useful for maintaining specific allele configurations that determine target quality profiles. Received: 28 May 1999 / Accepted: 9 November 1999     

Evaluation of nigerian millet (pennisetum typhoideum) as a raw material for beer production

Millet (Pennisetum typhoideum) its malt and wort were evaluated to ascertain the suitability of the grain for beer production. Thousand grain weight was 8.03 g while foreign material and broken cernels represented 3.23%. Germination energy, germination capacity and moisture content of the grain were 75.67, 92.33 and 10.43%, respectively, while the carbohydrate, total nitrogen and protein contents were 53.88, 1.34 and 8.40%, respectively. Millet malt had a moisture content of 5.03% while its carbohydrate, total nitrogen, protein content and malting loss were 48.47, 1.87, 11.7 and 8.3%. pH and specific gravity of the worth were 5.70 and 1.5927, respectively; its protein content was negligible while % titratable acidity was 1.35. The low nitrogen and protein contents of the grain as well as the low malting loss make millet an attractive alternative cereal for beer production in Nigeria.     

Effect of steeping and germination time on malting performance of Nigerian white and yellow maize varieties

Two maize varieties studied showed that the yellow maize variety had a better malting performance than the white maize variety. The yellow maize variety had lower malting losses, developed higher diastatic enzyme activity and produced more extract yield. The colored materials present in the grains of the yellow maize sample did not inhibit enzyme production of the grain because it developed higher enzyme activity and higher extract yield. The lower nitrogen content of the yellow variety was linked to high extract yield confirming the concept that extract yield is influenced by nitrogen content of the grain. The length of steeping had a significant influence on enzyme development and extract recovery.     

Hormonal changes in the grains of rice subjected to water stress during grain filling

Lodging-resistant rice (Oryza sativa) cultivars usually show slow grain filling when nitrogen is applied in large amounts. This study investigated the possibility that a hormonal change may mediate the effect of water deficit that enhances whole plant senescence and speeds up grain filling. Two rice cultivars showing high lodging resistance and slow grain filling were field grown and applied with either normal or high amount nitrogen (HN) at heading. Well-watered and water-stressed (WS) treatments were imposed 9 days post anthesis to maturity. Results showed that WS increased partitioning of fixed (14)CO(2) into grains, accelerated the grain filling rate but shortened the grain filling period, whereas the HN did the opposite way. Cytokinin (zeatin + zeatin riboside) and indole-3-acetic acid contents in the grains transiently increased at early filling stage and WS treatments hastened their declines at the late grain filling stage. Gibberellins (GAs; GA(1) + GA(4)) in the grains were also high at early grain filling but HN enhanced, whereas WS substantially reduced, its accumulation. Opposite to GAs, abscisic acid (ABA) in the grains was low at early grain filling but WS remarkably enhanced its accumulation. The peak values of ABA were significantly correlated with the maximum grain filling rates (r = 0.92**, P < 0.01) and the partitioning of fixed (14)C into grains (r = 0.95**, P < 0.01). Exogenously applied ABA on pot-grown HN rice showed similar results as those by WS. Results suggest that an altered hormonal balance in rice grains by water stress during grain filling, especially a decrease in GAs and an increase in ABA, enhances the remobilization of prestored carbon to the grains and accelerates the grain filling rate.     

Simulating nitrogen response of irrigated rice

A dynamic model to simulate the growth and yield of irrigated, transplanted rice in relation to daily solar radiation, mean temperature and shoot nitrogen concentration was applied to rice crops in western Java, Indonesia.Observations of shoot nitrogen concentration throughout the life-cycles of experimental crops were used as input to the simulation. The experiments consisted of 23 treatments representing different forms of nitrogen fertilizer, and different rates, times and methods of application. The model accurately fitted the growth and yield of 12 of these treatments and was successfully tested on the 11 treatments which were not involved in the filting.The parts of the model dealing with nitrogen simulate daily growth as a non-linear function of nitrogen concentration of non-grain shoot tissue relative to upper and lower limits. During the grain-filling phase the model simulates the competition for plant nitrogen between grain and assimilating tissue.The model was used to simulate the effects of increases in nitrogen status of a rice crop in the environmental conditions of western Java. Simulations with the model suggest an interaction between the timing and amount of nitrogen accumulation in plant tissue, with little effect of timing on yield for small increases in nitrogen status, but an advantage for early over late application for large increases in nitrogen status.     

A rapid technique to predict malting quality in barley prior to harvest

Samples of grain from three spring barley cultivars of differing malting quality were collected at regular intervals during four weeks prior to harvest. The samples were dried, then assessed for relative grain hardness using the "Milling Energy" test. Ranking order of the cultivars for this character, which relates strongly to malting quality, was unaltered throughout. In a further experiment, it was demonstrated that selection for milling energy could be successfully practised on oven-dried grain collected six weeks after ear emergence.     

花前渍水预处理对花后渍水逆境下扬麦9号籽粒产量和品质的影响

以扬麦9号为材料,研究花前渍水预处理对花后渍水逆境下小麦籽粒产量和品质的影响。结果表明,与未进行渍水预处理相比,花前渍水预处理提高了小麦植株对花后渍害的抗性,生物产量、收获指数和千粒重显著提高,进而显著提高了籽粒产量;花前渍水预处理显著提高花后氮素积累量及其对籽粒氮素的贡献率,降低了花前贮藏氮素运转量及其对籽粒氮素的贡献率,进而引起籽粒球蛋白含量提高,但显著降低了清蛋白、醇溶蛋白、谷蛋白和全蛋白质含量、以及干湿面筋含量和沉降值;花前渍水预处理还提高了籽粒直链淀粉和总淀粉含量和降落值,降低了支/直链淀粉比,显著提高了面粉峰值粘度、低谷粘度、崩解值、最终粘度、回冷值和峰值时间,但对糊化温度无显著影响。     

The effect of powdery mildew (Erysiphe graminis f.sp. avenae) on yield, yield components and grain quality of spring oats

Yield components and grain quality were investigated on eight cultivars of spring oats with known differences in adult plant resistance to mildew and with different fungicide treatments. Losses in grain yield caused by mildew could be accounted for mainly by reductions in numbers of fertile panicles and thousand grain weights. The proportion of grain yield to total biomass, (harvest index) was also reduced. There were no effects of treatment on the concentration of fatty acids in the grain, the proportions of the component fatty acids, the percentage content of grain protein or the specific weights. However, correlation analysis of the data revealed that percentage protein contents and specific weights were negatively correlated with levels of mildew. There were significant genetic differences between cultivars in all of the yield and quality characteristics but no fungicide treatment/cultivar interactions.     

Marker-assisted analysis of three grain yield QTL in barley (Hordeum vulgare L.) using near isogenic lines

Three previously identified grain yield quantitative trait loci (QTL) on chromosomes 2S(2HS), 3C(3HC) and 5L(1HL), designated QTL-2S, QTL-3 and QTL-5L, respectively, were evaluated for their potential to increase yields of high-quality malting barley without disturbing their favorable malting quality profile. QTL mapping of yield related traits was performed and near-isogenic lines (NILs) were developed. QTL for plant height, head shattering, seed weight and number of rachis nodes/spike were detected in the QTL-3 region. NILs developed by introgressing QTL-3 from the high-yielding cv. Steptoe to the superior malting quality, moderate-yielding cv. Morex acquired reduced height, lodging and head shattering features of Steptoe without major changes in malting quality. The yield of NILs, measured by minimizing the losses due to lodging and head shattering, did not exceed that of Morex. Steptoe NILs, with the Morex QTL-2S region, flowered 10 days later than Steptoe but the grain yield was not changed. None of the 3 QTL studied altered the measured yield of the recipient genotype, per se, although QTL 2S and QTL-3 affected yield-related traits. We conclude that these yield QTL must interact with other genes for full expression. Alternatively, they affect the harvestable yield through reduced lodging, head shattering, and/or altered flowering time.     

Partitioning of excitation energy in two wheat cultivars with different grain protein contents grown under three nitrogen applications in the field

Influences of different nitrogen applications on photosynthesis and utilization of excitation energy were explored by comparing two field-grown wheat ( Triticum aestivum L.) cultivars with high or low grain protein content [High protein cultivar '8901' (HC) and low protein cultivar '1391' (LC)]. High nitrogen application significantly decreased both CO₂ assimilation and photorespiration in both cultivars during the early stages after anthesis. However, the actual photosystem II (PSII) efficiency ( Ф _PSII) was not significantly different between high, moderate and low nitrogen applications in the HC. As a result, the ratio of Ф _PSII to the quantum yield of carbon metabolism ( Φ _CO2) measured under non-photorespiratory conditions in the HC was higher under high nitrogen application than under low or medium nitrogen application. The grain protein content of the HC was also increased by high nitrogen application. In contrast, high nitrogen application decreased the actual PSII efficiency in the flag leaves of the LC in the early stages after anthesis and different nitrogen applications did not significantly alter the Ф _PSII/ Φ _CO2 ratio or grain protein content in the LC. No significant difference was detected in the activity of superoxide dismutase or ascrobate peroxidase between different nitrogen treatments in either cultivar throughout the entire experimental period. These results indicate that more excitation energy is partitioned to nitrogen metabolism in the flag leaves of the HC under high nitrogen application whereas the partitioning of excitation energy in the LC was not affected by nitrogen application.     

Effect of mineral nitrogen on nitrogen nutrition and biomass partitioning between the shoot and roots of pea (Pisum sativum L.).

The effect of mineral N availability on nitrogen nutrition and biomass partitioning between shoot and roots of pea (Pisum sativum L., cv Baccara) was investigated under adequately watered conditions in the field, using five levels of fertiliser N application at sowing (0, 50, 100, 200 and 400 kg N ha^–1). Although the presence of mineral N in the soil stimulated vegetative growth, resulting in a higher biomass accumulation in shoots in the fertilised treatments, neither seed yield nor seed nitrogen concentration was affected by soil mineral N availability. Symbiotic nitrogen fixation was inhibited by mineral N in the soil but it was replaced by root mineral N absorption, which resulted in optimum nitrogen nutrition for all treatments. However, the excessive nitrogen and biomass accumulation in the shoot of the 400 kg N ha^–1 treatment caused crop lodging and slightly depressed seed yield and seed nitrogen content. Thus, the presumed higher carbon costs of symbiotic nitrogen fixation, as compared to root mineral N absorption, affected neither seed yield nor the nitrogen nutrition level. However, biomass partitioning within the nodulated roots was changed. The more symbiotic nitrogen fixation was inhibited, the more root growth was enhanced. Root biomass was greater when soil mineral N availability was increased: root growth was greater and began earlier for plants that received mineral N at sowing. Rooting density was also promoted by increased mineral N availability, leading to more numerous but finer roots for the fertilised treatments. However, the maximum rooting depth and the distribution of roots with depth were unchanged. This suggested an additional direct promoting effect of mineral N on root proliferation.     

Effects of fungicide treatments and variety on development, grain growth and yield of spring barley

The effects of four fungicide treatments for the control of mildew on spring barley were assessed in three field experiments, one in each of the years 1981, 1982, 1983. The fungicide treatments (+/ - triadimenol seed treatment and +/ - triadimefon foliar spray applied during early booting) were chosen to control mildew, and hence affect yield determining processes, at different times in the life of the crop. Two of the experiments also tested different nitrogen amounts and the third tested four varieties differing in their degree of mildew resistance. Mildew appeared too late to affect the production and survival of spikelets and shoots, but reduced average grain weight by reducing the rate of grain growth. Grains in the upper part of the ear had a considerably lower growth rate and final weight than grains in central and basal positions but there was no evidence that the effects of mildew on grain size depended upon grain position within the ear. Mildew incidence increased with increasing nitrogen and varietal susceptibility but there were few significant interactions between these factors and fungicide treatment for grain yield. The degree of mildew control achieved by the seed treatment varied with barley variety. Use of the two successive fungicide treatments did not yield more barley than use of either alone. Amongst varieties, grain positions within the ear and fungicide treatments there was a close correlation between rate of grain growth and final grain weight. Duration of grain growth was not related to rate of grain growth or final grain weight but was inversely correlated with mean temperature during the period of rapid grain growth. The temperature sums during the period of rapid grain growth were similar for the three years and it is suggested that a more precise knowledge of the relationships between mildew incidence, varietal susceptibility and rate of grain growth may enable more accurate predictions to be made about likely yield responses to fungicide treatments.     

Use of recombinant inbred lines of wheat for study of associations of high-molecular-weight glutenin subunit alleles to quantitative traits

Summary The high-molecular-weight glutenin subunits (HMW glutenin), encoded by alleles at homoeologous lociGlu-A1,Glu-B1, andGlu-D1 on the long arms of chromosomes1A,1B, and1D of a set of F₈ random recombinant inbred lines (RIL) derived from the bread wheat cross Anza × Cajeme 71, were classified by SDS-PAGE. Anza has poor breadmaking quality and HMW-glutenin subunits (Payne numbers) null (Glu-A1c), 7+8 (Glu-B1b), and 2+12 (Glu-D1a); Cajeme 71 has good quality and 1 (Glu-A1a), 17+18 (Glu-B1i), and 5+10 (Glu-D1d). The combinations of these alleles in the RIL were examined for associations with grain yield and four indicators of grain quality — protein content, yellowberry, pearling index, and SDS sedimentation volume. Data were obtained from a field experiment with three nitrogen fertilization treatments on 48 RIL and the parents. Orthogonal partitioning of the genetic variance associated with the three HMW glutenin subunit loci into additive and epistatic (digenic and trigenic) effects showed strong associations of these loci with grain yield and the indicators of quality; however, the associations accounted for no more than 25% of the differences between the parents. Genetic variance was detected among the RIL, which had the same HMW glutenin genotype for all traits. Epistatic effects were absent for grain yield and yellowberry, but were substantial for grain protein content, pearling index, and SDS sedimentation volume. All three loci had large single-locus additive effects for grain yield, protein, and SDS sedimentation volume. Yellowberry was largely influenced byGlu-B1 andGlu-D1, whereas pearling index was associated withGlu-A1 andGlu-B1. Even though the observed associations-of effects of HMW glutenin loci with the quantitative characters were small relative to the total genetic variability, they are of considerable importance in understanding the genetics of wheat quality, and are useful in the development of new wheat varieties with specific desired characteristics.     

QTL mapping reveals genetic architectures of malting quality between Australian and Canadian malting barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.)

Australia and Canada are major exporters of malting barley (Hordeum vulgare L.), with Baudin from Australia and AC Metcalfe from Canada being the benchmark varieties for premium malting quality in the past 10 years. We used the barley doubled haploid population derived from a cross of Baudin and AC Metcalfe to map quantitative trait loci (QTLs) for malting quality. The results revealed different genetic architectures controlling malting quality for the two cultivars. Sixteen QTLs were identified and located on chromosomes 1H, 2H, 5H and 7H. The Australian barley Baudin mainly contributed to the malting quality QTL traits of high diastatic power and high β-glucanase on chromosome 1H, while Canadian barley AC Metcalfe mainly contributed to the QTL traits of high hot water extract, high free amino nitrogen, high α-amylase and low malt yield in chromosome 5HL telomere region. This study demonstrated the potential to breed new barley varieties with superior malting quality by integrating genes from Australian and Canadian malting barley varieties. This paper also provides methods to anchor traditional molecular markers without sequence information, such as amplified fragment length polymorphism markers, into the physical map of barley cv. ‘Morex’.