M. Worku (2010). Prevalence and distribution survey of an invasive alien weed (Parthenium hysterophorus L.) in Sheka zone, Southwestern Ethiopia. African Journal of Agricultural Research 5(9): 922-927.
ABSTRACT Parthenium hysterophorus L, an invasive annual weed, is originated in tropical America and spread to Asia, Australia and Africa. In Ethiopia, it appeared first in Harrarghie in the 1970’s and it later spread to central, northern, southeastern and southern Ethiopia. Currently, it is spreading to Southwestern Ethiopia, but its prevalence and distribution has not been assessed and documented. So, a survey on its prevalence and distribution, awareness of its effects, and control measures taken was carried out in three ‘woredas’ (districts) of Sheka Zone, southwestern Ethiopia. The survey was carried out in 2001 using a questionnaire completed by Agricultural professionals and visual observations. Since 1999, P. hysterophorus was observed mostly on market places, road sides, and arable and waste lands of some areas of Yeki Woreda but not in the other Woredas. Almost all respondents knew about its invasiveness and adverse effects, and were able to identify it from other weeds. In different woredas of the zone, different mechanical control measures, teaching of the community and reporting to higher offices were attempted so far in order to minimize its further spread and adverse effects on ecology. However, more efforts and all combinations of possible preventive measures are needed to control its further invasions in the region.
Key words: Parthenium hysterophorus, weed, survey, prevalence, distribution.
- Arem. 01/1999; 5:14-26.
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ABSTRACT: Aqueous extracts of Parthenium hysterophorus leaf and flower seriously inhibited seed germination and seedling growth (root and shoot length) of lettuce. Extracts of the root and stem had much less effect. Lettuce roots were more sensitive to the allelopathic effect than shoots. It appears that early removal of Parthenium weed from lettuce fields is essential to avoid poor germination and seedling growth.Tropical Science 12/2005; 45:159 - 162.
Article: Parthenium: a wide angle view.Indian journal of dermatology, venereology and leprology 01/2007; 73(5):296-306. · 0.98 Impact Factor
African Journal of Agricultural Research Vol. 5(9), pp. 922-927, 4 May, 2010
Available online at http://www.academicjournals.org/AJAR
ISSN 1991-637X © 2010 Academic Journals
Full Length Research Paper
Prevalence and distribution survey of an invasive alien
weed (Parthenium hysterophorus L.) in Sheka zone,
Department of Horticulture and Plant Sciences, Jimma University College of Agriculture and Veterinary Medicine,
P. O. Box 307, Jimma, Ethiopia. E-mail: email@example.com.
Accepted 19 March, 2010
Parthenium hysterophorus L, an invasive annual weed, is originated in tropical America and spread to
Asia, Australia and Africa. In Ethiopia, it appeared first in Harrarghie in the 1970’s and it later spread to
central, northern, southeastern and southern Ethiopia. Currently, it is spreading to Southwestern
Ethiopia, but its prevalence and distribution has not been assessed and documented. So, a survey on
its prevalence and distribution, awareness of its effects, and control measures taken was carried out in
three ‘woredas’ (districts) of Sheka Zone, southwestern Ethiopia. The survey was carried out in 2001
using a questionnaire completed by Agricultural professionals and visual observations. Since 1999, P.
hysterophorus was observed mostly on market places, road sides, and arable and waste lands of some
areas of Yeki Woreda but not in the other Woredas. Almost all respondents knew about its invasiveness
and adverse effects, and were able to identify it from other weeds. In different woredas of the zone,
different mechanical control measures, teaching of the community and reporting to higher offices were
attempted so far in order to minimize its further spread and adverse effects on ecology. However, more
efforts and all combinations of possible preventive measures are needed to control its further invasions
in the region.
Key words: Parthenium hysterophorus, weed, survey, prevalence, distribution.
Parthenium hysterophorus L. is an annual herbaceous
weed native to Central America. Its reproduction is
entirely by seed and its growth proceeds through a
rosette stage to the flowering plant (Cock and Seier,
1999; McGuire, 2005). It is an aggressive weed and a
serious problem for major crops, rangelands and
wastelands. The weed is known for its allelopathic effects
on other plants as well as contact dermatitis and
respiratory effects on humans and livestock (Lakshmi and
Srinivas, 2007). It releases phytotoxic substances into its
immediate environment, which highly inhibits germination
and growth of several plant species (Tadele, 2002;
Mulatu et al., 2005; Maharjan et al., 2007; Mulatu, 2009;
Mulatu et al., 2009). A considerable reduction in yield of
crops, weight of grazing animals, and yield and quality of
cow milk due to its allelopathic, competitive and skin
allergy properties has also been reported (Naithani, 1987,
Tamado et al., 2002; Rupschus et al., 2007). It is an
alternate host for many crop pests and an inter-season
reservoir or sources of inocula. As a result, vigorous
growth of many crops and grazing plants is difficult on
lands invaded by P. hysterophorus (Labrada et al., 1994;
Evans, 1997; Kassahun et al., 1999; McGuire, 2005;
Janke et al., 2008). P. hysterophorus weed has achieved
a major weed status in Australia and in India within a
relatively short period of time. It is not included in the
„Weeds of Australia‟ of 1976 and the „World‟s Worst
Weeds‟ of 1977, but it is indicated in the „Noxious Weeds
of Australia‟ of 1992 (Evans, 1997). The reports from
Israel (Joel and Liston, 1986), Taiwan (Peng et al., 1988),
Nepal (Mishra, 1991) and Ethiopia (Medhin, 1992) were
an indicator of further spreading and more prominent
appearance of it in other parts of the World. Currently, it
is a widely distributed and problematic weed for crops,
livestock, human health and biodiversity in India,
Australia, south China, The Caribbean, and in south and
east Africa (Cock and Seier, 1999; McGuire, 2005). For
sure, parthenium weed has come to the fore in the last 20
years in most countries, mainly based on its prolific seed
production, an enormous seed bank, rapid spread and
aggressive colonization (Evans,
preventive methods that restrict the entrance of weed
seed into a non-infested area and uprooting of the weed
before flowering and seed setting is indicated as the most
effective and less costly strategy to manage parthenium
(APFISN, 2007). In addition to preventive and mechanical
methods, some chemicals, biological agents and
bioherbicides have also been reported promising to
control parthenium and some of them are widely used in
many countries, e.g. India and Australia (APFISN, 2007;
Lakshmi and Srinivas, 2007; Fauzi, 2009).
P. hysterophorus invaded regions of Ethiopia are well
known following its discovery in the 1970‟s. Its
introduction to Ethiopia was probably via food grain aid
from North America (Kassahun et al., 1999) and/or army
vehicles during the 1976-1977 Ethio-Somalia war
(Tamado, 2001). It first appeared in Harrarghie in the
1970‟s, and it spread later to central, northern,
northwestern, southeastern and southern Ethiopia
(Matiyas, 1999; Rezene et al., 2005). It has come the
most dominant weed and is ranked as the worst and
more frequent species of weed in areas of eastern,
central and northern Ethiopia (Tamado and Milberg,
2000; Mulugeta 2006; Shashie, 2007; Adane, 2008). Due
to its high reproductive and disseminative potential, as
well as its prolific growth nature on non-arable lands, the
weed is currently spreading at an alarmingly fast rate,
colonizing large areas. It is heavily invading most areas
of agricultural lands, rangelands and wastelands of
eastern, southeastern and northern parts of Ethiopia. It is
causing the same problem regardless of the crops grown
and the preventive/control measures (e.g. mostly hand
weeding and hoeing, and in some cases chemical
control) (Kassahun et al., 1999; Tamado, 2001; Rezene
et al., 2005; Yenealem, 2008). As previous reports
indicated, the prevalence and distribution of the weed
was extremely high and its problem seems to be the very
fast spreading into previously un-invaded regions of the
country. Its expansion to southwestern Ethiopia has also
been observed along the road from Addis Ababa to the
Sheka Zone and Gambela region (Rezene et al., 2005).
However, knowledge on its prevalence, distribution and
adverse environmental effects in southwestern Ethiopia,
and in Sheka Zone in particular, were not assessed and
documented. Hence, the P. hysterophorus prevalence
and distribution, the level of knowledge to identify it from
other weeds and its adverse effect on the environment,
as well as the preventive measures taken so far in Sheka
Zone was surveyed to provide baseline information for
further work on its management.
The study area (Sheka Zone), situated in southwestern Ethiopia,
lies between 7°24‟ to 7°52‟ N, 35°13‟ to 35°35‟ E and 900 to 2700 m
asl. The zone covers about 2175.25 km2, out of which 47% is
covered by forest, and 56, 24 and 20% is a highland, a mid altitude
and lowland, respectively. It receives high amounts of rainfall, with
an average between 1800 to 2200 mm per annum. The major crops
grown in the zone are maize, sorghum, millet, beans, coffee,
ginger, turmeric, „enset‟, wheat, barley and pea. The zone is divided
into three administrative „woredas‟ (districts), namely Yeki,
Anderacha and Masha, each having 6 to 11 development stations,
DSs. A general survey of P. hysterophorus prevalence and
distribution, level of knowledge to identify this weed from other
weeds and about its adverse effects to the environment, the areas
where it is most frequently found, and the kinds of preventive or
control measures attempted so far was studied in all three woredas
of the zone during the main cropping season (July to September) of
The survey was conducted using a questionnaire completed by
each agricultural experts, AEs, (n = 35) of each woreda and each
agricultural development agents, DAs, (n = 16) of Yeki and
Anderacha Woreda, and by direct visual observations in the market
places, cultivated lands, grazing lands and wastelands, as well as
along road sides in each DSs and towns of Yeki (n =13) and
Anderacha (n = 6). The questionnaire, prepared in English for AEs
and in Amharic (local language) for DAs, consisted of the following
items: (1) whether the agricultural professionals heard about the
invasiveness of P. hysterophorus or not, (2) whether P.
hysterophorus is introduced in each respondent‟s localities or not
and its time of introduction, (3) whether the respondents can
identify it from other weeds or not, (4) the level of knowledge of the
respondents about its adverse effect on crops or the environment,
(5) the place where it is mostly localized, and (6) whether
preventive or control measures were attempted or not, and if
attempted, what kinds of preventive or control measures were
attempted so far. Finally, the questionnaires were collected and the
results of the responses and the observations were summarized in
percentage. Distribution/invasion was determined as presence or
absence of parthenium in the market areas, cultivated lands,
grazing lands, wastelands and along road sides in each survey site.
If observed, prevalence was estimated for each woreda separately
following the method adopted by Javaid and Riaz (2007).
The result showed that P. hysterophorus has become the
major weed of market areas, road sides, and arable,
grazing and waste lands of Sheka area, particularly the
Yeki Woreda (Table 1) with prevalence of 23.1%. All AEs
and DAs in the Yeki Woreda knew P. hysterophorus and
could identify it from other weeds (Table 2). Moreover,
they pointed out that P. hysterophorus has been
introduced in Tepi town in around 1999. However, its
introduction in some rural areas of Yeki (Shuma, Fidie
and Beko DSs) has been in around mid 2001 and in the
Zinki areas in mid 2000. There was no P. hysterophorus
weed in most other rural areas of this woreda (Yeki,
Endris, Dapi Chenigawie, Michi-komi, Kubito, Gelecha
and Achanie DSs) until August 2001 (Table 1). In invaded
areas, it is mostly found along roadsides and in arable
and waste lands. It is also observed abundantly in market
areas of Tepi town and very minimal prevalence
(scattered patches) in the surrounding small towns (Fidie
and Zinki) of Yeki. Its growth in Yeki has been observed
as robust and prosperous. Similarly, in the Masha and
Anderacha Woredas, all respondents have heard about
924 Afr. J. Agric. Res.
Table 1. Summary of parthenium weed invasion, time of introduction, area of invasion and control measures taken in the Sheka Zone in 2001.
Woredas Invasion Time of introduction Invasion area Awareness of its
Control measures taken
and Fidie DSsa
Market areas, road
sides, and arable,
grazing and waste
burning, hand pulling and
burning or burying, teaching,
and reporting to higher offices
None until 2001
None until 2001
None until 2001
aDS is development station and DSs are development stations.
Table 2. The percentage of agricultural professionals that can identify parthenium weed from other weeds and their awareness about its effect on
environment in the Sheka Zone in 2001.
Heard about parthenium (n =11) (n =20)
Yes 100 100
No - -
Identify parthenium (n =11) (n =20)
Yes 100 100
No - -
Awareness of parthenium adverse effects (n =11) (n =20)
Well aware 90.9 60.0
A little aware 9.1 35.0
Not aware - 5.0
b DA is development agent and AE is agricultural experts
this weed and most of them can identify the weed from
other weeds (Table 3). Unlike in the Yeki P.
hysterophorus, however, has not been observed both in
town and in rural areas of these two woredas until this
survey time, 2001.
The adverse effect of P. hysterophorus on the
environment in general is well known by almost all DAs
and AEs (71, 67 and 75% of the respondents in Yeki,
Anderacha and Masha, respectively) (Table 2).
Moreover, depending on the conditions of the localities,
different control and/or preventive measures were
attempted to restrain its further distribution in the zone.
The control measures taken in the Yeki were slashing,
slashing or hand pulling followed by burning or burying,
teaching both urban and rural dwellers, and reporting to
DA and DE
DA and DE
higher levels. Only teaching of both urban and rural
dwellers was done in Anderacha and no control or preventive
measures at all was made in the Masha (Table 1).
P. hysterophorus has become a major weed of various
areas of Ethiopia in a relatively short period of time. The
result of the present study revealed this fact in the Sheka
Zone. The weed has been found in market areas, road
sides, and arable, grazing and waste lands of some
areas of Yeki Woreda since 1999 (Table 1). The growth
was robust and prosperous. As reported by Tamado et al.
(2002) and APFISN (2007), this can be related to the
Table 3. Percentage of agricultural professionals‟ views about the year of parthenium introduction in their localities, the place
where it was found and the control or preventive measures taken in the Sheka Zone in 2001. The figures under control or
preventive measures taken do not add up to 100% because some respondents listed more than one control or preventive
(n = 12)
(n = 12)
(n = 8)
(n = 8)
(n = 8)
Time of introduction
A few months ago
A year ago
Two years ago
No parthenium until now
The place where it found
Road sides only
Also arable and waste lands
Control or preventive measures taken
Slashing and burning
Hand pulling and burning
Teaching farmers and urban dwellers
Reporting to higher levels
The combination of the above
Others (slashing only/hand pulling and burying)
Figure 1. Maps showing (a) areas surveyed in southwestern Ethiopia and (b) other administrative
zones of Ethiopia.
suitable climates (high moisture and high temperature) of
the area and wider adaptability of the weed to various soil
types. In addition to its seeds introducing into the region
from other areas, Yeki areas can be a source of seeds for
further dispersion into un-invaded areas of the zone and
neighboring areas by vehicles, flood, animal feet, animal
feed and farm products. A similar area and pattern of
invasion and domination
hysterophorus was also noticed by Tamado and Milberg
(2000) in Eastern Ethiopia, by Oudhia (2001) in India,
and by Shabbir and Bajwa (2006) in Pakistan. This
shows that P. hysterophorus can invade large areas
of vegetation by P.
926 Afr. J. Agric. Res.
within a few years as it did in other areas unless more
effort is made to control its distribution. The abundance of
the weed in market areas of Tepi town and the very
minimal appearance in the surrounding small towns of
Yeki Woreda, and not at all in the Masha and Anderacha
until 2001 might be due to higher market activities and
more frequent entrance and exit of vehicles in Tepi town
as compared to small towns and the later two woredas.
This indicates that the most probable distribution
mechanism of the seed to previously un-invaded areas of
the zone are market commodities including animals
brought for exchanges and vehicle bodies such as tires.
According to Navie et al. (1996), most of the long -
distance seed dispersal in India and Australia is through
vehicles, farm machineries and flooding. Thus, at its
current rate of spread, which can be accelerated by the
ongoing expansion of rural roads and deforestation for
agricultural land, it will definitely invade different areas
within few years unless effective preventive measures,
such as washing of vehicles and farm machineries before
entering into non-infested areas, use of weed free cattle
feeds and crop seeds, keeping of cattles in yards or small
paddocks, and uprooting of the weed before flowering
and seed setting (APFISN, 2007), are implemented.
The adverse effect of P. hysterophorus on the
environment in general is well known by almost all AEs
and DAs in the zone (Table 2) and they tried to take
some control and/or preventive measures to restrain its
further distribution in the zone. E.g. different mechanical
control (slashing) and preventive measures were taken in
Yeki, teaching in Anderacha but no actions in Masha
(Tables 1 and 3). The latter is due to the absence of this
weed in the area. However, due to its high germination
and regeneration capacity, huge amount of seed
production and a wide range of ecosystems‟ adaptability
(APFISN, 2007), a single weed control measure such as
mechanical methods might not be sufficient to manage
this weed. Repeated ploughing during land preparation
and hoeing during the early growth stages reduce its
population. But, hoeing or slashing of mature plants is
ineffective as it induces regrowth from crown buds
(Matiyas, 1999). Various preventive measures that
restrict the entrance of weed seeds into non-infested
areas, and uprooting of the weed before flowering and
seed setting is indicated as the most effective methods to
manage parthenium (APFISN, 2007). Some chemicals
(e.g. glyphosate, atrazine and metribuzin), biological
agents (e.g. Zygogramma bicolorata, Puccinia abrupta
and Cassia tora) and bioherbicides (e.g. foliar extracts of
Azradiracha indica, Aegle marmelos and Eucalyptus
terteticomis) have also been reported promising to
minimize parthenium infestation (APFISN, 2007; Lakshmi
and Srinivas, 2007; Fauzi, 2009). However, there is no
single method used to control P. hysterophorus as each
method has one or more limitations such as high cost,
environmental safety, inefficiency and impracticability
(Shashie, 2007). So, it is mandatory to use integrated
P. hysterophorus management methods that involves the
use of different preventive and control options. It can be
concluded that P. hysterophorus weed has been
introduced into Sheka zone, Tepi town, in 1999. It is more
serious in Yeki than in the other woredas and in market
places and along road sides than in arable and waste
lands. Despite the various efforts made to control its
further expansion, it is still spreading very rapidly to other
areas of the Yeki Woreda. It can also further spread to
other woredas of the zone by movement of vehicles,
livestock, market commodities, crop produce and flooding
and affect the livelihood of numerous farmers in the
region. So, future studies focusing on the management of
this weed to control its further spread in the zone and
neighboring regions are highly recommended. Use of all
possible preventive options (e.g. cleaning of farm imple-
ments, use of weed free seeds, minimizing free grazing,
managing of wastelands and grazing lands through
uprooting weeds and growing of competitive plants) in
combination with available control methods is also
needed. In addition, it should be supplemented with good
publicity through mass media, video, posters, field days
and seminars, and organization of people‟s participation
in uprooting the weed before flowering and seed setting.
I thank Mr. Tadesse Eshetu for his support in designing
the questionnaire and
professionals for their collaboration in completing the
questionnaire. The Tepi Agricultural Research Center is
acknowledged for the vehicle and other relevant logistic
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