Management Options and Factors Affecting Control of a Common Waterhemp (Amaranthus rudis) Biotype Resistant to Protoporphyrinogen Oxidase-Inhibiting Herbicides
Table 5
The effect of herbicide placement on the response of protox herbicide-resistant common waterhemp. Criteria for evaluating common waterhemp included visual control, height reduction, and fresh-weight reduction 21 d after treatment.
Treatment
Rate
Placement
Control
Height reduction
Fresh-weight reduction
g ai/ha
%
Nontreated
Soil only
0
0
0
Lactofen
220
Soil only
0
8
6
Acifluorfen
420
Soil only
0
12
13
Fomesafen
330
Soil only
0
1
3
Flumioxazin
72
Soil only
0
12
11
Nontreated
Foliar only
0
0
0
Lactofen
220
Foliar only
13
13
14
Acifluorfen
420
Foliar only
13
17
17
Fomesafen
330
Foliar only
13
16
17
Flumioxazin
72
Foliar only
15
18
16
Nontreated
Soil + foliar
0
0
0
Lactofen
220
Soil + foliar
8
11
13
Acifluorfen
420
Soil + foliar
17
18
19
Fomesafen
330
Soil + foliar
24
29
33
Flumioxazin
72
Soil + foliar
32
36
36
LSD ()
3
2
7
All treatments included diammonium sulfate at 2.8 kg/ha and crop oil concentrate at 1.2 l/ha.