|
Weed control and crop
tolerance to herbicides in no-till dry pea (Williston 2004).
‘Scuba’ dry pea was direct
seeded May 4 into durum wheat stubble at 195 lb/A into 7-inch rows. Individual
plots were 10 x 30 ft and replicated three times. Preemergence (PRE) and
postemergence (POST) herbicides were applied May 7 and June 14, respectively.
The study was conducted on a loam soil with pH 5.5 and OM 2.3%. The primary
weeds present were green foxtail (Grft), Russian thistle (Ruth) and kochia (Kocz).
Dry pea density tended to
decrease with higher Spartan rates. Visible crop injury increased with higher
Spartan rates. However, dry pea yield was not reduced despite the slight impact
on crop density and visible injury. Sencor applied PRE with Spartan also caused
moderate crop injury, but with no impact on dry pea yield.
All treatments provided
good to excellent control of green foxtail, Russian thistle, and kochia.
Treatments with Spartan provided slightly better weed control compared to total
postemergence treatments.
|
|
|
|
Dry pea |
Grft |
Ruth |
Kochia |
|
Treatmenta |
Rate |
Timing |
Jun
2 |
Jun 6 |
Jun 30 |
Jun 6 |
Jun 30 |
Jun 6 |
Jun 30 |
Jun 6 |
Jun 30 |
|
|
|
|
#/m row |
% injury |
————— % control ————— |
|
Raptor + Basagran +
NIS + 28% N |
4 oz + 1 pt +
0.25% v/v + 1
qt |
POST
|
9.0 |
0 |
6 |
0 |
90 |
0 |
91 |
0 |
93 |
|
Spartan/
Select + COC |
2.67 oz/
5 fl oz + 1%
v/v |
PRE/
POST |
7.5 |
7 |
5 |
93 |
100 |
100 |
100 |
100 |
100 |
|
Spartan/
Select + COC |
4 oz/
5 fl oz + 1%
v/v |
PRE/
POST |
7.0 |
13 |
10 |
96 |
100 |
98 |
100 |
100 |
100 |
|
Spartan/
Select + COC |
5.33 oz/
5 fl oz + 1%
v/v |
PRE/
POST |
6.1 |
19 |
19 |
99 |
100 |
100 |
100 |
100 |
100 |
|
Basagran +
Poast + COC |
2 pt +
1 pt + 2 pt |
POST
|
10.0 |
0 |
4 |
0 |
91 |
0 |
99 |
0 |
95 |
|
Spartan/
Basagran +
Poast + COC |
2.67 oz/
1 pt +
1 pt + 2 pt |
PRE/
POST
|
8.1 |
7 |
5 |
94 |
98 |
100 |
100 |
100 |
100 |
|
Spartan + Sencor/
Select + COC |
4 oz + 0.25 lb/
5 fl oz + 1%
v/v |
PRE/
POST |
7.3 |
15 |
27 |
98 |
100 |
100 |
100 |
100 |
100 |
|
Untreated |
|
|
8.3 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
LSD (0.05) |
|
|
1.5 |
3 |
6 |
3 |
4 |
2 |
2 |
NS |
6 |
|
CV |
|
|
10.6 |
25 |
36 |
2 |
3 |
2 |
2 |
0 |
4 |
aRoundup
UltraMax II plus AMS was applied PRE to each treatment at 11 oz + 2.5
gal/100gal.
| 