Table S1. Mean values of barley varieties for agronomic traits: plant height at the beginning of stem elongation stage (PH1), and at maturity (PH2), days to heading (DH) and days to maturity (DM) at two organic (O1 and O2) and two conventional sites (C1 and C2), 2006-2008. The extreem values for each trait are highlighted in bold

Variety / PH1 / PH2 / DH / DM
cm / cm / days / days
Abava / 29.4 / 74.9 / 60 / 103
Annabell / 21.0 / 58.7 / 60 / 102
Anni / 22.0 / 60.3 / 60 / 103
Ansis / 21.5 / 63.5 / 62 / 103
Dziugiai / 34.5 / 81.8 / 57 / 100
Idumeja / 29.8 / 66.5 / 54 / 97
Inari / 25.9 / 66.0 / 58 / 101
Latvijasvietejie / 25.6 / 88.6 / 64 / 107
Primus / 26.5 / 95.4 / 60 / 103
Rubiola / 27.9 / 70.1 / 61 / 103

Table S2. Analysis of variance p-values for the effects of main factors: conventional versus organic management systems, year, site and variety, and their interactions for grain yield (GY), number of tillers (NT), thousand grain weight (TGW) and number of kernels per tiller (NK) between two organic sites (O1 and O2) and two conventional sites (C1 and C2),in 2006 -2008.‘Site’ refers to Farming system/site, so in the statistical model sites were nested within farming systems. A split-plot structure was used where complete replicates (blocks) were nested within environments, and experimental units (the field plots) within blocks.

Source of variation / GY / NT / TGW / NK
Year / .001 / .001 / .001 / .001
Farming system (conventional versus organic) / .001 / .001 / 0.200 / 0.308
Site / 0.007 / .001 / .001 / 0.288
Year × Farming system / .001 / 0.149 / .001 / .001
Year × Site / 0.004 / .001 / .001 / .001
Genotype / .001 / .001 / .001 / .001
Genotype × Year / .001 / .001 / .001 / 0.002
Genotype × Farming system / 0.006 / .001 / .001 / 0.041
Genotype × Farming system × Year / 0.048 / .001 / .001 / 0.034
Genotype × Site / 0.080 / 0.096 / .001 / 0.190
Genotype × Year × Site / 0.032 / 0.043 / .001 / 0.097

Analyses of variance for grain yield (GY)

Source of variation / df / SS / MS / F / Sig.
Year / 2 / 115.4425 / 57.7213 / 37,45 / ,001
Farming system (conventional versus organic) / 1 / 106.4106 / 106.4106 / 69.03 / .001
Year × Farming system / 2 / 77.5537 / 38.7768 / 25.16 / .001
Site / 2 / 17.8821 / 8.9411 / 5.8 / 0.007
Year × Site / 3 / 24.6377 / 8.2126 / 5.33 / 0.004
Residual / 33 / 50.8678 / 1.5414 / 9.95
Genotype / 9 / 70.7182 / 7.8576 / 50.73 / .001
Genotype × Year / 18 / 19.833 / 1.1018 / 7.11 / .001
Genotype × Farming system / 9 / 3.6458 / 0.4051 / 2.62 / 0.006
Genotype × Farming system × Year / 18 / 4.5987 / 0.2555 / 1.65 / 0.048
Genotype × Site / 18 / 4.2492 / 0.2361 / 1.52 / 0.08
Genotype × Year × Site / 27 / 6.7155 / 0.2487 / 1.61 / 0.032
Residual / 297 / 45.9992 / 0.1549
Total / 439 / 508.7813

Table S3.Correlation coefficients between barley yield (GY) and number of tillers (NT), thousand grain weight (TGW), number of kernels per ear (NK), plant height at the beginning of stem elongation stage (PH1), and at the maturity (PH2), days to heading (DH) and days to maturity (DM) A.Ten varieties (the complete set), and B. Eight varieties (excluding old varieties ‘Latvijasvietejie’ and ‘Primus’) grown under two organic (O1 and O2) and two conventional sites (C1 and C2), 2006-2008

A.

Traits / Growing sites
O1 / O2 / C1 / C2
2006 / 2007 / 2008 / 2007 / 2008 / 2006 / 2007 / 2008 / 2006 / 2007 / 2008
NT / 0.52 / 0.68* / 0.59 / 0.51 / 0.22 / 0.44 / 0.85** / -0.13 / 0.58 / 0.69* / 0.40
TGW / -0.50 / -0.60 / 0.20 / 0.63* / 0.22 / 0.15 / -0.23 / -0.12 / -0.41 / -0.43 / -0.20
NK / 0.63* / 0.62 / 0.69* / 0.68* / 0.80** / 0.76* / -0.05 / 0.88** / 0.69* / 0.75* / 0.94**
PH1 / -0.06 / -0.18 / -0.06 / -0.15 / 0.18 / -0.29 / -0.40 / -0.12 / - / -0.12 / 0.24
PH2 / -0.32 / -0.80** / -0.55 / -0.67* / -0.23 / -0.50 / -0.75* / -0.38 / -0.56 / -0.74* / -0.46
DH / -0.34 / -0.04 / -0.55 / -0.11 / 0.09 / -0.41 / -0.08 / -0.09 / 0.01 / -0.12 / 0.01
DM / -0.35 / -0.42 / -0.37 / -0.07 / 0.28 / -0.24 / -0.02 / -0.14 / 0.08 / -0.24 / 0.30

1* = p < 0.05; ** = p < 0.01

B.

Traits / Growing sites
O1 / O2 / C1 / C2
2006 / 2007 / 2008 / 2007 / 2008 / 2006 / 2007 / 2008 / 2006 / 2007 / 2008
NT / 0.76*1 / 0.50 / 0.03 / 0.42 / 0.07 / 0.46 / 0.69 / -0.12 / 0.50 / 0.23 / -0.09
TGW / -0.16 / -0.33 / 0.79* / 0.00 / 0.51 / 0.04 / -0.18 / 0.54 / -0.30 / -0.08 / 0.46
NK / -0.10 / 0.26 / 0.55 / 0.50 / 0.79* / 0.22 / 0.13 / 0.77* / 0.49 / 0.86* / 0.92*
PH1 / 0.02 / -0.88* / 0.03 / -0.28 / 0.06 / -0.51 / -0.68 / -0.27 / - / -0.47 / 0.07
PH2 / 0.21 / -0.55 / 0.14 / -0.21 / 0.01 / -0.37 / -0.32 / 0.17 / -0.19 / -0.33 / 0.08
DH / 0.02 / 0.69 / -0.01 / 0.45 / 0.47 / 0.30 / 0.75* / 0.68 / 0.41 / 0.64 / 0.71*
DM / 0.07 / 0.56 / 0.19 / 0.80* / 0.75* / 0.51 / 0.79* / 0.77* / 0.60 / 0.57 / 0.83*

1* = p < 0.05; ** = p < 0.01

Table S4. Spearman correlation coefficients (r) of grain yield (GY), number of tillers (NT), thousand grain weight (TGW) and number of kernels per tiller (NK) A. ten varieties (the complete set), and B. eight varieties (exculding old varieties ‘Latvijasvietejie’ and ‘Primus’) between two organic sites (O1 and O2) and two conventional sites (C1 and C2)

A.

Year / GY / NT / TGW / NK
C1 / C2 / O1 / C1 / C2 / O1 / C1 / C2 / O1 / C1 / C2 / O1
2006 / C2 / 0.95**1 / 0.89** / 0.57 / 0.81**
O1 / 0.81** / 0.78** / 0.55 / 0.52 / 0.60 / 0.74* / 0.72* / 0.63
2007 / C2 / 0.91** / 0.83** / 0.91** / 0.37
O1 / 0.88** / 0.81** / 0.57 / 0.56 / 0.45 / 0.73* / -0.03 / -0.13
O2 / 0.88** / 0.81** / 0.84** / 0.66* / 0.46 / 0.81** / 0.23 / -0.11 / -0.51 / 0.33 / 0.06 / 0.75*
2008 / C2 / 0.88** / 0.28 / 0.95** / 0.56
O1 / 0.74* / 0.64* / 0.08 / 0.73* / 0.83** / 0.87** / 0.42 / 0.91**
O2 / 0.89** / 0.91** / 0.56 / 0.54 / 0.50 / 0.59 / 0.89** / 0.89** / 0.98** / 0.57 / 0.66* / 0.33

B.

GY / NT / TGW / NK
Year / C1 / C2 / O1 / C1 / C2 / O1 / C1 / C2 / O1 / C1 / C2 / O1
2006 / C2 / 0.93**1 / 0.88** / 0.7 / 0.65
O1 / 0.51 / 0.56 / 0.55 / 0.54 / 0.78** / 0.68 / 0.12 / 0.17
O2 / - / - / - / - / - / - / - / - / - / - / - / -
2007 / C2 / 0.82* / 0.62 / 0.98** / 0.42
O1 / 0.80* / 0.56 / 0.34 / 0.28 / 0.84** / 0.85** / 0.12 / -0.38
O2 / 0.73* / 0.55 / 0.50 / 0.63 / 0.32 / 0.79* / 0.58 / 0.52 / 0.23 / 0.49 / -0.11 / 0.66
2008 / C2 / 0.83** / 0.5 / 0.89** / 0.30
O1 / 0.69 / 0.39 / -0.47 / 0.34 / 0.88** / 0.92** / 0.04 / 0.87**
O2 / 0.89** / 0.92** / 0.51 / 0.19 / 0.08 / 0.04 / 0.93** / 0.92** / 0.98** / 0.48 / 0.65 / 0.22

1** = p < 0.01; * = p < 0.05

The highest correlation coefficients per trait and year are marked in bold between organic sites

Table S5.Grain yield of ten barley varieties, grown in eleven organic and conventional environments. Environments are arranged according to the average yield over varieties from lower to higher yields

Varieties / Environments
O2 / O1 / O1 / C1 / C2 / O2 / C2 / C2 / C1 / O1 / C1
2007 / 2007 / 2006 / 2006 / 2006 / 2008 / 2007 / 2008 / 2008 / 2008 / 2007
Abava / 1.85 / 2.65 / 3.07 / 3.13 / 3.63 / 3.92 / 4.15 / 4.83 / 4.59 / 4.94 / 5.09
Annabell / 2.35 / 2.78 / 2.86 / 3.41 / 4.06 / 2.95 / 4.52 / 3.57 / 3.85 / 3.89 / 5.41
Anni / 1.78 / 2.82 / 3.02 / 3.21 / 3.88 / 4.29 / 4.16 / 4.79 / 4.57 / 4.51 / 5.07
Ansis / 2.44 / 2.92 / 2.37 / 2.86 / 3.54 / 3.79 / 3.90 / 4.33 / 4.65 / 4.82 / 5.31
Dziugiai / 1.71 / 2.48 / 2.83 / 2.84 / 3.41 / 3.43 / 3.42 / 3.98 / 3.97 / 3.97 / 4.13
Idumeja / 1.72 / 2.45 / 2.42 / 2.77 / 3.07 / 2.87 / 3.39 / 3.04 / 3.47 / 4.45 / 4.37
Inari / 1.77 / 2.63 / 2.56 / 3.40 / 3.88 / 3.97 / 3.97 / 4.13 / 4.85 / 5.05 / 4.47
Latvijasvietejie / 0.93 / 1.91 / 1.80 / 1.98 / 2.83 / 2.89 / 3.01 / 2.81 / 3.04 / 3.43 / 3.75
Primus / 1.18 / 2.25 / 2.20 / 2.07 / 2.78 / 3.61 / 3.23 / 3.56 / 4.09 / 3.50 / 3.77
Rubiola / 2.29 / 2.49 / 2.38 / 2.84 / 3.26 / 4.02 / 4.15 / 4.53 / 4.39 / 4.19 / 4.86
Average yield per environment / 1.80 / 2.54 / 2.55 / 2.85 / 3.43 / 3.57 / 3.79 / 3.96 / 4.15 / 4.28 / 4.62
LSD site*year = 0.55
LSD variety*site*year = 0.75