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mesotrione, S-metolachlor and dimethenamid-P. Whereas active
ingredients that can be applied post-emergence include bendioxide,
mesotrione, glyphosate, tembotrione, 2,4-D, topramezone, dicamba,
and bromoxynil.
Glasshouse trials were conducted at the ARC-Grain Crops Institute
(Potchefstroom) where six products with
the following active ingredients were tested
for effective control of Benghal wandering
Jew: Flumetsulam (800 g/kg), acetochlor/
atrazine/terbuthylazine (250/225/225 g/l),
mesotrione/S-metolachlor (83,3/416,7 g/l),
S-metolachlor (915 g/l), dimethenamid-P
(720 g/l) and acetochlor (840 g/l).
These herbicides were all applied pre-
emergence (before emergence of weed).
In two other trials, eight products with the
following active ingredients were tested
for effective control of Benghal wandering
Jew: Bendioxide (480 g/l), mesotrione
(480 g/l), glyphosate/mesotrione/S-meto-
lachzlor (250/25/250 g/l), tembotrione
(420 g/l)), glyphosate (540 g/l), glyphosate
(540 g/l) and 2,4-D (480 g/l), topramezone/
dicamba (50/160 g/l) and bromoxynil
(225 g/l).
These herbicides were applied post-
emergence (after weed emergence) at
two different growth stages namely when
the weed had four leaves fully unfolded
(V4) and at flowering. The following
control standards were used in this study:
Control between 90% and 100% indicated
‘acceptable, sufficient or effective’ weed
control; between 50% and 89% indicated
‘reduced or suppressed’ weed control,
and less than 50% weed control is totally
unacceptable for producers indicating
‘insufficient control’.
Visual evaluations of necrosis, yellowing,
twisting or curling of leaves were recorded
for each treatment and compared to control
treatments which received no herbicide to
record a percentage of Benghal wandering
Jew control. The regrowth of Benghal
wandering Jew was measured weekly
after application of the respective post-
emergence herbicides.
Pre-emergence application
All products applied at pre-emergence,
effectively controlled Benghal wandering
Jew (90% to 100%) 40 days after application, except where
flumetsulam (800 g/kg) was applied. Flumetsulam (800 g/kg) gave
poor control of only 22% and is therefore classified as ‘insufficient’
weed control for Benghal wandering Jew. Only products containing
mesotrione/S-metolachlor (83,3/416,7 g/l) and S-metolachlor
(915 g/l) gave complete control of 100% (
Graph 1
).
Graph 1: The percentage control of Benghal wandering Jew where six pre-emergence herbicides
were applied (means above bars followed by the same letter[s] do not differ significantly from one
another).
Graph 2: The percentage control of Benghal wandering Jew at the V4 growth stage where eight
different herbicides were applied (means above bars followed by the same letter[s] do not differ
from one another).
3a and 3b: Rooting at the nodes and fleshy subterranean seed, below the soil surface.
3a
3b