Page 145 - Breeding and regulatory opportunities, Renaud

Broccoli crop improvement

Table 4.8 Genetic correlation of broccoli horticulture traits across organic and conventional trials (upper

right of diagonal, organic; lower left of diagonal, conventional).

ty
er mie ty
Horticulture ht etm e rcht ali
igmteor ape
fofagQu
Traits
WeDia Sty
olhizniurei
owrid Cd S S Ud S Hall
adadlltuaaadadanter
HeHeHoMaHeHeBeBeHelaOv
P
Head Weight
0.83
-0.18
0.30
-0.25
0.32
0.49
0.38 0.17 0.32 0.74

Head Diameter
0.76
-0.16
-0.10
-0.20
-0.12
0.33 0.31
-0.09
0.54
0.73

Hollow Stem
-0.09
-0.05
0.01
-0.02
0.20
0.12
-0.01
0.07
-0.21
-0.03
Maturity 0.39 -0.06
0.16
-0.28
0.60
0.61
-0.09
0.07
-0.22
-0.04

Head Color
0.29 0.15 0.32 0.16 -0.31
-0.26
-0.32
-0.29
0.15 0.02

Head Shape
0.39 0.37 0.42
-0.08
0.22
0.65
0.12
0.54
0.61
-0.10

Bead Size
0.30
0.13 0.39
0.66
0.29
0.10
0.66
-0.25
0.64
-0.04

Bead Uniformity
0.12
0.35
0.32 0.46
0.46
-0.16
-0.16
0.06
0.73
0.42
Head Surface 0.13 0.25
0.14
-0.02
0.59
0.05
0.42
0.25 0.11 0.33

Plant Height 0.19 0.41
-0.11
0.12
0.64
0.09
-0.30
-0.24
0.63
0.35

Overall Quality
0.64
0.55
0.46
0.53
0.69
0.52
0.61
-0.10
0.09 0.21

Values ≤ |0.40| are not signiicantly diferent from zero at the P < 0.05 level

4.4 Discussion

4.4.1 Relative importance of Management system, Location, and Season

Overall, our trials demonstrated that Location and Season, not Management

System, are the largest source of environmental variation in broccoli cultivar

performance. The signiicantly higher broccoli head weight from the Oregon

trials compared to the Maine trials in both seasons as well as the overall

higher broccoli head weight across all trials in the Fall compared to the Spring

supported these indings. Higher head weight overall in the Oregon ield trials

could be explained by the climatic diferences between Oregon and Maine

with Oregon having more growing degree days than Maine in both Fall season

trial years (Table 4.2). For many traits, Management system contributed only

to variation at the three- and four-way interaction level, and these interactions

constituted a large portion of the total variance in the model. Thus, genotype

by management systems interactions did occur, but there were no overarching

efects of management system apparent across locations and seasons.

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