Agriculture Reference
In-Depth Information
Galium aparine in winterwheat
Alopecurus myosuroides in winterwheat
1000
1500
y = 14.601x + 262.06
r
2
= 0.19
y = 18.185x + 275.82
r
2
= 0.05
750
1000
500
500
250
0
0
0
2
4
6
8
10
12
14
0 0 0 0 0 0 0 0 0
Galium aparine
in spring barley
Galium aparine
in sugarbeet
250
3000
2500
y = 81.026x - 229.02
r
2
= 0.48
200
y = 0.8617x + 64.516
r
2
= 0.11
2000
150
1500
100
1000
50
500
0
0
0
15
30
45
60
0
5
10
15
20
weed density [plantsm
-2
]
Fig. 10.11
Weed density and seed production of catchweed (Galium aparine) and blackgrass
(Alopecurus myosuroides) in various crops (Ritter and Gerhards
2008
)
10000
y = 108.82x - 37.443
r
2
= 0.73
8000
6000
4000
2000
0
0
10
20
30
40
50
60
70
80
weed biomass [g/plant]
Fig. 10.12
Correlation of weed biomass and seed production of catchweed (Galium aparine) and
blackgrass (Alopecurus myosuroides) over all crops (Ritter and Gerhards
2008
)
density dependent. It was presumed that individual weeds without competition
evolve better and produce more seeds, but this study showed opposing results. With
increasing weed density, weed biomass and fecundity increased in this study
(Figs.
10.11
and
10.12
). All fi ndings support that weed density has to be considered
in weed management strategies.
An understanding of fundamental weed population biology would improve our
ability to develop site-specifi c management decisions.
Weed populations models
have been applied to quantify the effects of site-specifi c weed management practices
