The Malting Barley Blues

Figures & data

Table 1. Total number of genotypes (#G), number of blue genotypes (#B) identified by color values measured via colorimeter (bB, see materials and methods) in the 2021 season of the present study, and proportion of blue genotypes (#B/#G) for each family observed in this study.

Pedigree	#G	#B	#B/#G
DH140963/Flavia	92	92	1.00
DH120304/Flavia	53	17	0.32
DH141944/Lyberac	14	1	0.07
DH150115/DH130939	4	1	0.25
DH120304/Mateo	3	1	0.33
DH142000/Lyberac	4	0	0.00
DH140963/Thunder	3	3	1.00
Lightning/Thunder	2	2	1.00
Total	175	117	0.67

Figure 1. Pearled grain used in the scoring of aleurone color with dark blue receiving a 1, blue receiving a 2, medium or light blue receiving a 3, and white receiving a 4.

Table 2. Results from the ANOVA and variance component estimation of the across-year values.

Parameter	LB	aB	bB
Genotype	0.71***	0.29***	0.31***
Year	0.01***	0.53***	0.49***
Genotype*Year	0.28***	0.18***	0.20***
Rep(Year)	0.00	0.00	0.00
Residual	0.00	0.00	0.00
H2	0.83	0.76	0.75

***; Significance at the α = 0.001 level determined via ANOVA.

Variance attributed to each of the parameters as a proportion of the total variance is provided for LB, aB, and bB. Broad-sense heritability (H2) is also estimated on an entry-mean basis.

Figure 2. Distributions of the bB colorimeter value across all genotypes of the Cycle 5 Panel in the 2021 harvest season (A) and the 2022 harvest season (B). Check genotypes are indicated and labeled in red.

Figure 3. Pearson correlation matrix relating the different measures of grain aleurone color. All values were recorded in 2021 at minimum, with the LB, aB, and bB values also collected in 2022.

Figure 4. Pearson correlation matrices relating the bB value of grain aleurone color, and ten of the malting parameters measured in this study. The left matrix shows correlations across the entire Cycle 5 population. The right matrix shows only the correlations within the DH120304/Flavia pedigree.

Figure 5. Boxplots of A) S/T, B) DP, C) FE, and D) BG broken out by the observed aleurone color from the 2021 harvest season. Letters at the base of each plot are the result of a Fisher’s LSD Test to detect significant differences between groups. A jitter plot is overlaid on each boxplot to show exact data values. The Fisher’s Test for beta-glucan is based on values transformed via Box-Cox transformation to account for non-normality; however, the displayed data values are untransformed.

Table 3. Results from the ANOVA and Fisher’s LSD test comparing the performance of each observed aleurone color group with regards to ten of the measured malting traits.

Trait	p-value	White	Blue	Transformation
FAN	<2.0E-16***	276.2a	214.1b	Box-Cox λ= −0.38
Diastatic power	<2.0E-16***	170.0a	142.1b
Soluble/total protein	1.5E-12***	49.3a	42.4b
Water sensitivity	7.9E-10***	8.5b	15.6a
Wort color	2.4E-09***	2.3a	1.9b	Box-Cox λ= −1.60
Alpha-amylase	6.7E-08***	65.7a	56.6b
Beta-glucan	5.8E-05***	95.4b	153.5a	Box-Cox λ= −0.18
Friability	1.9E-02*	85.8a	83.3b
Total protein	2.9E-01	11.7a	11.6a
Fine extract	9.8E-01	79.3a	79.3a

***, **, *; Significance at the α = 0.001, 0.01, and 0.05 levels, respectively.

The p-value associated with the effect of aleurone color as well as the mean values for each of the color groups are provided. Significant differences between individual color groups are provided as the lowercase letter after the mean value. Transformations to the data are indicated and used to account for departures from normality.

Figure 6. A scatterplot plotting anthocyanin content against the measured bB value in 2021. Point shapes are based on the visual score for blue aleurone with squares indicating light blue, triangles indicating blue, and circles indicating dark blue.

Figure 7. Boxplots of A) S/T B) DP, C) FE, and D) BG broken out by the observed aleurone color from the 2021 harvest season within the DH120304/Flavia Pedigree. Letters at the base of each plot are the result of a Fisher’s LSD Test to detect significant differences between groups. A jitter plot is overlaid on each boxplot to show exact data values. The Fisher’s Test for beta-glucan is based on values transformed via Box-Cox transformation to account for non-normality; however, the displayed data values are untransformed.

Table 4. Results from the ANOVA and Fisher’s LSD test comparing the performance of the blue and white aleurone color groups within the DH120304/Flavia subset.

Trait	p-value	White	Blue	Transformation
Diastatic power	0.001**	173.9a	159.6b
Fine extract	0.002**	79.2b	80.2a
Wort color	0.170	2.5a	2.7a	Box-Cox λ = 0.63
Total protein	0.321	11.7a	11.5a
Friability	0.365	87.6a	88.8a
Alpha-amylase	0.502	66.5a	68.1a
Beta-glucan	0.577	81.9a	106.5a	Box-Cox λ= −0.38
FAN	0.584	290.4a	283.9a
Water sensitivity	0.808	8.6a	8.3a
Soluble/total protein	0.990	50.5a	50.5a

**; Significance at the α = 0.01 level.

The p-value associated with the effect of aleurone color as well as the mean values for each of the color groups are provided. Significant differences between individual color groups are provided as the lowercase letter after the mean value.

Figure 8. Manhattan plots with a significance threshold resulting from the GWAS analysis showing significant peaks for the aleurone color traits A) bB as measured from the 2021 harvested grain, B) bB as measured from the 2022 harvested grain, C) intensity of blue aleurone measured from the 2021 harvested grain, and D) proportion of grains with blue aleurone measured from the 2021 harvested grain.

Figure 9. Manhattan plots with a significance threshold resulting from the GWAS showing significant peaks for the malting traits A) FAN, B) WC, C) S/T, and D) AA.

Figure 10. A subset of malt and aleurone color QTL mapped to their respective positions on the barley genome. The position outlined in red is of the most significant marker for a given peak. Trait associated with each QTL as well as the year identified are provided.

Data availability

Phenotypic data will be available on the Triticae Toolbox T3/Barley.