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Effective control of
Benghal wandering Jew
T
he Benghal wandering Jew, also known as the tropical
spiderwort (
Commelina benghalensis
), is one of the world’s
worst weeds reported in 25 different crops such as soy-
bean, maize and sugarcane in 29 different countries (Holm
et al
., 1977).
This weed is a strong competitor with row crops for water and
nutrients and can reduce cotton and peanut yields up to 60% and
100% respectively, through season-long interference (Webster
et al
., 2009). Infestation levels of wandering Jew has been reported
to increase in crop production fields due to its resistance or
high tolerance to many commonly used herbicides, particularly
glyphosate (Owen and Zelaya, 2005).
Benghal wandering Jew has a prostrate growth habit (
Photo 1a
and
Photo 1b
) and can behave as a perennial in tropical zones or as an
annual in more temperate zones (Wilson, 1981).
Benghal wandering Jew has the unique ability to produce both
aerial (
Photo 2a
and
Photo 2b
) and subterranean flowers with seed
(
Photo 3a
and
Photo 3b
). The aerial fruit contains one large and four
small seed whereas the subterranean seed capsule contain one large
and only two small seed.
The small aerial seed has a greater dormancy compared to the larger
seed (Budd
et al
., 1979). It has been estimated that one Benghal
wandering Jew has the ability to produce 1 600 seeds (Wilson,
1981). Benghal wandering Jew is difficult to control due to its ability
to reproduce in several ways i.e. with seed and vegetatively where
rooting occurs at the nodes of stems (Photo 3a and Photo 3b).
It has been found in the USA, as is the case in South Africa, that
Benghal wandering Jew has a high tolerance against glyphosate
and can pose a serious problem since it is most commonly used
to control this weed in glyphosate resistant maize and soybean
cultivars (Culpepper
et al
., 2004).
Registered pre-emergence herbicides, which are most commonly
applied to control Benghal wandering Jew in crops include active
ingredients such as flumetsulam, acetochlor, atrazine, terbuthylazine,
ON FARM LEVEL
Benghal wandering Jew / Tropical spiderwort
Integrated pest control
LOUIS REYNOLDS
and
JOHNNIE VAN DEN BERG,
Unit for Environmental Sciences and Management:
North-West University and
ELBÉ HUGO,
ARC-Grain Crops Institute, Potchefstroom
1a and 1b: Prostrate growth of Benghal wandering Jew and regrowth from older plant parts.
2a and 2b: Aerial flower head and seed pockets.
1a
2a
1b
2b