Influence of Farmers` Crop Management Practices on Striga hermonthica Infestation and Grain Yield of Maize (Zea mays L.) in the Savanna Zones of Northeast Nigeria
The aim of this study was to assess the influence of farmers` crop
management practices on Striga infestation and maize grain yield.
Sixty farmers` fields were randomly selected in nine communities across
three savanna zones. About 35% of the farmers had cultivated their fields
for over 10 years, 48% grew the Striga resistant variety 97 TZL
Comp-1-W, 68% planted maize in mid-June and 60% practiced legume-maize
rotation. About 33% intercropped maize + cowpea, 42% applied 100 kg N
ha-1 and 87% conducted 2 to 3 hoe weedings. The Striga
resistant maize variety reduced Striga count and host damage score
and increased grain yield ha-1 in northern and southern Guinea
savannas. However, the varieties grown in Sudan savanna increased Striga
count ha-1 (R = 0.56**) and Striga damage (R = 0.59**)
because they were not resistant to Striga. Planting maize in mid-July
reduced Striga infestation in northern Guinea, but grain yield
ha-1 was highest when maize was planted in mid-June in all
three zones. Soybean-maize or groundnut-maize rotation reduced Striga
count in all the agro-ecosystems. Relay intercropping of cowpea into maize
reduced Striga count in northern Guinea. Higher nitrogen fertilizer
rate reduced Striga count and score and significantly increased
grain yield in the three zones. Two or three hoe weedings reduced Striga
count in the three zones and Striga score in Sudan savanna. Thus,
the farmers` practices sampled significantly influenced Striga
infestation of maize fields in the three agro-ecosystems. The Striga
resistant maize variety, Soybean-maize rotation, 100 kg N ha-1
and three hoe weedings could serve as component technologies in an integrated
package for combating Striga menace in the region.
to cite this article:
I.Y. Dugje, A.Y. Kamara and L.O. Omoigui, 2008. Influence of Farmers` Crop Management Practices on Striga hermonthica Infestation and Grain Yield of Maize (Zea mays L.) in the Savanna Zones of Northeast Nigeria. Journal of Agronomy, 7: 33-40.
Striga hermonthica (Del.) Benth., a root parasitic
flowering plant endemic in Africa, constitutes one of the most severe
constraints to cereal production in sub-Saharan Africa (Dashiell et
al., 2000). It is estimated that over 20 million ha are infested in
the region, causing annual losses of more than four million tonnes of
grain and affecting the lives of about 300 million people (Sauerborn,
1991). A survey of Striga sp. on cereals in northern Guinea savanna
of Nigeria showed that Striga hermonthica had become a serious
problem (Weber et al., 1995; Kim et al., 1997) and yield
losses ranging from 10 to 100% have been reported (Lagoke et al.,
1991; Oikeh et al., 1996). Striga infestation can become
so severe that farmers abandon cereal production in their fields (Lagoke
et al., 1991).
Farmers rated Striga infestation as the leading priority constraint
together with low soil fertility during a livelihood analysis in 30 communities
in Borno State, northeast Nigeria (PROSAB, 2004). Further assessment of
the level of Striga infestation in the communities showed that
68% of all fields sampled were infested with four Striga species,
S. hermonthica was responsible for damage in 86% of all
fields; about 94% of sorghum fields and 77% of maize fields were infested
(Dugje et al., 2006). PROSAB (2004) further reported that farmers
in the savanna zones of southern Borno area of northeast Nigeria generally
cultivate farmlands with short fallow periods or none. This often resulted
in environmental degradation, such as soil erosion, leaching, reduced
soil fertility and Striga infestation. The application of N fertilizers
and organic amendments can generally correct the situation. However, fertilizers
are not readily available or too costly. The average rate of fertilizer
use in Nigeria is about 12 kg nutrient ha-1, of arable land,
figures for other West African countries are lower (FAO, 1992).
Apart from routine crop management practices, farmers cope with Striga
infestation and low soil fertility by employing crop rotation, hand pulling
of Striga plants, land rotation and the application of inorganic
fertilizer (Emechebe et al., 2004; PROSAB, 2004). Ogborn (1987)
reported that Striga infestation levels in peasant farmers` field
vary according to farming practices. Manyong et al. (1996) reported
that S. hermonthica infestation had become a serious problem
in areas of poor market access where farmers did not apply fertilizer
adequately to maize in northern Guinea savanna of Nigeria. An important
characteristic of maize is its high and relatively rapid nutrient requirement.
Weber et al. (1995) and Kim et al. (1997) reported that,
high nitrogen application (>120 kg ha-1), reduced Striga
infestation significantly. Apparently, low N application, a sorghum dominated
farming system, reduced fallow periods or none and low soil fertility
are major causes of Striga infestation in West and Central Africa
(Kim et al., 1997). Oswald and Ransom (2001) showed that Striga
control in low external input farming systems depends on several components,
such as hand weeding, crop rotation and soil fertility management. These
need to be combined in an integrated approach, not only to reduce Striga
densities but also to improve soil fertility.
Several Striga reducing technologies promoted by Agricultural
Development Projects have found their ways into the hands of the farmers
in Southern Borno area. These technologies include Striga resistant
maize varieties, legume-cereal rotation and nitrogen fertilization, hand
pulling of Striga plants and timely weeding (PROSAB, 2006). In
spite of the promotion of these Striga reducing technologies for
maize production, infestations have continued to manifest as observed
for S. hermonthica in the region. However, there is no information
on whether these management practices influence Striga infestation
in maize fields in the savanna zones of northeast Nigeria. The objective
of this study was to assess the influence of these management practices
on Striga infestation and develop an integrated approach for combating
its menace and improving maize production in the region.
MATERIALS AND METHODS
The field study was conducted in 2005 during a rainy season between
May and October in Northern Guinea Savanna (NGS), Southern Guinea Savanna
(SGS) and Sudan Savanna (SS) zones in the southern part of Borno State
(11° 50` E and 10° 25`N) of northeast Nigeria. The three ecological
zones are distinguished by differences in the amounts of average annual
rainfall, length of the growing season, temperatures and soils as described
by PROSAB (2004) and Dugje et al. (2006). Average annual rainfall
in SS ranges from about 500 to 800 mm; average temperatures are between
22 and 37°C and length of growing season is 100-120 days (June to
September). In NGS, average annual rainfall is from 900 to 1000 mm; average
temperatures are between 23-35°C and length of growing season is 120-150
days (June to October). In the SGS, average rainfall is from 1000 to 1200
mm, average temperatures are between 22 and 35°C and length of growing
season is 150-180 days (May to October). Soils range from sandy clay (SS)
to clay loam in NGS and SGS (PROSAB, 2004; Dugje et al., 2006).
Random sampling and field observations was used to select 60 farmers
and their maize-based fields in 3 communities in each ecological zone.
These comprised an average of 20 farmers and maize-based fields/zone and
6-7 farmers and maize-based fields/community. Available fields were randomly
selected from the four cardinal points (north, east, west and south) of
each community. Fields less than 1 km from the edge of the community were
considered to be compound fields; that more than 1 km distant was considered
bush fields. The participating farmers grew mono crop of maize or practiced
legume-maize rotation with soybean or groundnut, or sorghum-maize rotation
in 2004. Fertilization ranged from zero to 100 kg N ha-1 in
the form of NPK and Urea depending on affordability. The farmers applied
the fertilizer rates in one or two split doses. The maize+cowpea relay
intercropping system was planted as mixed intercropping system. The maize
component in the system was either a local or an improved variety. The
farmers relayed cowpea into maize 4 to 5 weeks after planting maize. They
prepared their land mainly with tractor or ox-plough in SS and NGS, while
ox-plough and no-tilled land were common in SGS. They also conducted 1-3
weedings during the season.
Farmers` routine crop management practices and cropping history was assessed
through field monitoring and observations and administration of a semi-structured
questionnaire to each farmer on the field selected. Each farmer served
as a replicate. Emerged Striga hermonthica plants were counted
from each field as described by Kim (1994). Five 1 m2 quadrats
were marked out with sticks in each plot along a diagonal transect at
15-20 m intervals in each of the fields sampled. Damage score were taken
based on a 9-point rating score in each field, as described by Kim (1991),
where 1 = no chlorosis, no blotching, no leaf scorching or firing, normal
plant growth, 9 = complete scorching of all leaves causing premature death
of host plant and no ear formation. Grain yield was determined from a
net plot of 16 m2 measured from three places in each field
sampled and converted to ha.
Data collection and statistical analysis: Emerged Striga
plant count m-2 was converted ha-1 and transformed
using square root transformation. The transformed values, Striga
score were each subjected to analysis of variance (ANOVA) using the General
Linear Model (GLM) procedure of the Statistical Analysis Systems (SAS)
package (SAS, 1990). Statistically significant differences between variable
means were compared using Standard Error of Difference (p<0.05). Pearson`s
correlation co-efficient was calculated among the parameters and quantitative
crop management variables using PROC CORR of SAS (1990).
RESULTS AND DISCUSSION
Outline of farmers` crop management practices: Fifty percent
of the farmers sampled in NGS have been cultivating their farmland for
more than 10 years (Table 1). The number was 35% in
SGS and 20% in SS. About 25 and 70% of the farmers in NGS and SGS, respectively,
cultivated the Striga resistant maize variety 97 TZL Comp-1-W and
25-35% grew local varieties. Thirty five percent of the farmers cultivated
the Striga tolerant maize variety 94 TZE Comp-5-W in SS. The increase
in use of the improved maize varieties is due to their promotion by PROSAB
Project over the past 3 years (PROSAB, 2006).
Table 1 data also showed that most farmers (65-70%)
sampled across the three zones planted maize in mid-June in all the three
zones. The early on-set of rainfall in the humid ecological zones encouraged
farmers to plant earlier in these zones than in SS. Majority (45-50%)
of the farmers in NGS and SGS practiced soybean-maize rotation, while
majority of the farmers in SS (45%) practiced groundnut-maize rotation,
20% practiced soybean-maize rotation and 15% continuous cropping of maize.
Maize-sorghum rotation was practiced by 25% in SS and by 15% in NGS. In
both NGS and SS, 35-40% of the farmers practiced relay cropping of maize
+ cowpea, while majority of the farmers grow sole maize in the three agro-ecosystems.
||Farmer crop management practices sampled (%) in the savanna zones
of northeast Nigeria
uring the period of study, 15-25% of farmers in the three agro-ecosystems
could not apply nitrogen fertilizer (Table 1). However,
100 kg N ha-1 was applied by 45% in NGS and by 35% in SS. The
remaining 40-45% applied 15-30 kg N ha-1 and these rates were
70-85% less than the recommended rate of 100 kg N ha-1. About
10-15% of the farmers conducted one hoe weeding during the cropping season
(Table 1). The majority (50-70%) of the farmers conducted
two hoe weedings, in the three ecological zones, but more farmers in NGS
conducted three hoe weedings probably because of increased land use intensification
in the zone.
Influence of farmers` crop management practices on Striga infestation
and grain yield: The Striga resistant maize variety 97 TZL
Comp-1-W significantly reduced Striga plants ha-1 (p<0.01)
and host damage score (p<0.05) more than the drought-tolerant maize
variety TZE Comp-3DT-W or the farmers` choice in the NGS and SGS (Table
2). Emechebe and Ahonsi (2002) reported 97 TZL Comp-1-W as a long-duration
type that showed fewer attacks in terms of the number of emerged Striga
plants than the common local varieties. These confirm reports from Kim
(1994) and Kim et al. (1997) that genetic variability exists among
maize germplasm in their response to S. hermonthica parasitism.
The use of varieties resistant or tolerant to Striga has been recommended
as the most practical approach for resource-poor smallholder farmers in
Africa (Kim, 1991). Grain yield ha-1 was significantly higher
(p<0.05) for the Striga resistant variety than for the drought
tolerant variety or the farmers` choice.
Planting maize in mid-July significantly (p<0.05) reduced Striga
count compared to planting in mid-May or mid-June in NGS and SGS (Table
2). However, grain yield ha-1 was significantly (p<0.01)
higher for mid-June planting than the other planting dates in the two
ecologies. This confirms the study of Weber et al. (1995) who reported
that farmers plant early (mid-June) because they obtained higher maize
yield with early planting to capture N flush during this period in the
savannas and in most cases the maize is harvested before Striga
reproduction thus reducing the seed bank. Parker and Riches (1993) reported
that the intensity of S. hermonthica infestation is highest
in earliest plantings where rainfall is mono-modal, as in the study area.
This implies that early planting could result in an increase in Striga
infestation, as the host is able to produce adequate stimulants to promote
Striga seed germination and enable more haustoria to attach (Emechebe
et al., 1991). Although late planting reduce infestation because
of shortening of the period of Striga conditioning and increase
in rainfall later in the season, the delay results in reduced grain yield
as observed in NGS.
||Effect of maize variety and planting date on Striga count
ha-1, Striga score and grain yield (kg ha-1)
in farmers` fields in Guinea and Sudan savannas
|Significant: *: p<0.05, **: p<0.01, values in
parenthesis are square root transformed value of Striga counts
In SS, Striga count and host damage score (p<0.05) on the Striga
tolerant maize variety 94 TZE Comp-5-W and the extra early maturing variety
95 TZEE-W were significantly less than on the farmers` choice (Table
2). The variety 94 TZE Comp-5-W has been reported to be tolerant to
Striga (Jennifer Kling, Personal Communication), while 95 TZEE-W,
though not tolerant, escapes damage because of its ability to grow faster
and complete its life-cycle before Striga begins to attach and
draw assimilates. These varieties undergo senescence before Striga
plants are able to produce seeds, thus reducing the seed bank in the soil.
The ability of these varieties to escape Striga damage is attributed
to several mechanisms. These range from short growth cycle (escape mechanism),
root architecture (fewer roots in the upper soil layer), early growth
and vigour, to physiological resistance to the phytotoxic effects caused
by Striga parasitism (Oswald and Ransom, 2001).
Rotating maize with soybean (Glycine max (L.) Merrl.) significantly
reduced Striga plants ha-1 in all the zones (Table
3). The practice of continuous maize cropping or sorghum-maize rotation
(Sorghum bicolor (L.) Moench) recorded significantly higher Striga
counts than soybean-maize or groundnut-maize rotation (Arachis hypogaea
L.). However, continuous maize cropping had slightly lower Striga
count than sorghum-maize rotation. Striga scores were slightly
lower for legume-maize than cereal-cereal rotations. Similarly, Kureh
et al. (2005) reported a reduction in Striga infestation
and damage in maize when sown after soybean or cowpea. Grain yield ha-1
was significantly (p<0.05) higher for soybean-maize rotation than for
any of the cereal-cereal rotations. The lowest (p<0.01) grain yield
was observed for sorghum-maize rotations (2.2-2.7 t ha-1) in
the Guinea savannas and for continuous maize system (2.1 t ha-1)
in the SS. The yield increase for maize following soybean or groundnut
was attributed to a combination of reduced S. hermonthica
parasitism and improved nitrogen supply.
The present study did not measure the N contribution from the preceding
soybean crop but the variety used, TGX-1448-2E, is late maturing and significantly
reduced Striga infestation and increased maize grain yield more
than continuous mono cropping of maize or sorghum. Singh et al.
(2003) showed that planting medium or late maturing soybean for one season
resulted in an addition of N to the soil, as grain legumes release N through
the roots during the growth period or through their crop residues after
decomposition. Agboola and Fayemi (1972) reported that this N, after the
decomposition of leaves, roots and nodules, might accrue more to the subsequent
crop than the companion crop.
The preceding crop of soybean or groundnut in the present study probably
provided more N to maize through crop residues after decomposition, as
observed from the negative influence it had on Striga infestation
and the increase in grain yield. Apart from increasing soil N balance,
soybean suppresses Striga emergence by causing suicidal germination
of Striga seeds (Carsky et al., 2000).
Relay intercropping of maize with cowpea (Vigna unguiculata (L.)
Walp.) reduced (p<0.01) Striga count by 19 to 78% more than
sole cropped maize in NGS and SGS (Table 3). In addition,
slightly lower values were observed for maize + cowpea intercrop than
sole maize in SS. Although grain yield ha-1 was significantly
(p<0.05) higher for sole maize than intercropped maize in SGS, no significant
difference was observed in NGS and SS. Similarly, intercropping maize
with cowpea reduced (p<0.05) Striga score in SGS and slightly
lower value was observed in NGS. Intercropping cereals with legumes is
a traditional system in the study area. This is done to diversify food
production, reduce risk of crop failure and enable more efficient utilization
of growth resources than is possible with sole cropping.
||Effects of crop rotation, relay inter cropping, nitrogen fertilizer
rate and weeding frequency on Striga count ha-1,
Striga score and grain yield (kg ha-1) of maize
in farmers` fields in Guinea and Sudan savannas
|Significant *: p<0.05, **: p<0.01, values in parenthesis
are square root transformed value of Striga counts
Intercropping legumes with cereals could decrease the number of Striga
plants leading to reduced Striga infestation in the following crop
(Carsky et al., 1994). This may be due to the legume acting as
a trap crop, suppressing Striga germination or producing a shading
effect (Oswald et al., 2002). Beneficial effects of legumes, such
as cowpea, have been demonstrated in many studies as grain legumes release
N through the roots during the growth period. Others are of the view that
N benefit may be due to a ‘sparing effect` whereby legumes, because
of their ability to fix N, take up less N from the soil than cereals (Oswald
et al., 2002). The N fixed and released by cowpea might also contribute
to Striga suppression in intercropping since the amount of available
N apparently affects Striga density (Pieterse and Verkleij, 1991).
Shading effect and/or suppression of emergence due to stimulatory effect
on Striga seeds are probably more plausible explanations for the
effect of cowpea on Striga infestation. This is because cowpea
does not release much N into the soil during its growth (Van der Heide
et al., 1985) and large amounts of N are usually required to reduce
Striga density (Mumera and Below, 1993). The cowpea components
in the relay were mostly the local varieties (Borno brown and Gwalam white)
that are photosensitive, spreading and late maturing.
Application of higher amount of N fertilizer generally significantly
reduced Striga count ha-1 (p<0.01) and Striga
score (p<0.01) and increased grain yield ha-1 in the three
ecologies (Table 3). The order of reduction in Striga
population and Striga score with a corresponding increase in grain
yield was 100 kg N >30 kg N >15 kg N >0 kg N ha-1.
The benefits of N fertilization were more apparent between 0 kg N ha-1
and the highest nitrogen rate (100 kg N ha-1) as Striga
count was lower by 43-89.3% and damage score by 46.8-71.7% at 100 kg N
ha-1 than at 0 kg N ha-1. These results corroborate
similar findings by Mumera and Below (1993), Kim et al. (1997)
and Kureh et al. (2005) who reported that adequate N, especially
Urea and legume-cereal rotation are effective in reducing Striga
emergence, host damage and Striga dry weight in maize and sorghum.
On the contrary, Kabambe et al. (2005) found fertilization had
no effect on reducing the emergence of S. hermonthica and
S. asiatica infestation in early maturing maize varieties,
probably due to the earliness, which allows maize to escape Striga
parasitism before the N, becomes effective. The practice of applying small
doses of N in the form of urea (46%) N and compound (NPK) fertilizers
may actually promote Striga infestation rather than reduce it,
as observed for 15 kg N ha-1 in NGS and SS. However, the fact
that a positive response to N was observed for as low as 30 kg N ha-1,
clearly shows that inadequate soil nitrogen is a major constraint to maize
production in the region. Pieterse and Verkleij (1991) cautioned that
N fertilization of very infertile soils or low doses of N might stimulate
Striga infestation. Kim et al. (1997) reported that 120
kg N ha-1 reduced Striga in maize hybrids.
Two or three hoe weedings significantly reduced (p<0.01) Striga
count ha-1, more than one weeding (Table 3).
Striga score was also reduced (p<0.01) by two or three weedings
in SS, but no significant difference was observed in both NGS and SGS.
However, grain yield ha-1 was significantly (p<0.01) increased
with increase in weeding frequency in both Guinea savannas, but no such
effect was observed in SS. The presence of weeds due to poor farm sanitation
exacerbates the effect of Striga parasitism as weeds compete with
crops for nutrients, moisture and light. Lagoke et al. (1991) and
Mumera and Below (1993) reported that Striga infestation and host
damage are usually more severe under abiotic stress such as low soil moisture
and low N. Weber et al. (1995) reported that the later the last
weeding the lower is the number of visible, emerged Striga plants.
The removal of the Striga plants before flowering may reduce the
Striga seed bank and subsequent infestation.
Linear relationships between farmer practices, Striga parameters
and grain yield: The linear relationships between farmer management
practices, Striga parameters and maize grain yield ha-1
in each of the three zones are shown in Table 4. In
NGS, a prolonged period of land use was positively associated with Striga
count (R = 0.43*). This suggests increased land use intensification, which
puts more pressure on land, leading to a decline in soil fertility and
an increase in Striga infestation in the zone. The practice of
growing a Striga resistant maize variety in the zone was negatively
associated with Striga count (R = -0.67**) and score (R = -0.48*)
and positively correlated with grain yield ha-1 (R = 0.62**).
Similarly, soybean-maize rotation was negatively correlated with Striga
count (R = -0.37*) but positively associated with grain yield ha-1
(R = 0.43*) thus suggesting the influence of resistant varieties and legume-cereal
rotation as an effective farmer practice for reducing Striga infestation
and increasing grain yield. Relay intercropping of maize with cowpea was
negatively associated with Striga count (R = -0.79**). Both Striga
count (R = -0.74**) and Striga score (R = -0.71**) were negatively
associated with an increase in the N fertilizer rate which was positively
correlated with grain yield ha-1 (R = 0.57**).
||Linear correlation coefficient (r) of farmer crop management practices
on Striga count ha-1; Striga score and grain
yield of maize in farmers` fields in Guinea and Sudan savannas
|**: Significant (p<0.01), *: (p<0.05). Values
without asterisk have no significant linear correlation, df = 6
The situation in SGS was similar to that in the NGS, as growing Striga
resistant varieties was negatively associated with Striga count
(R = -0.65**) and positively associated with grain yield ha-1
(R = 0.61**). Planting date was negatively associated with Striga
count (R = -0.45*) and positively correlated with grain yield ha-1
(R = 0.56**) thus implying a wider scope for manipulating planting dates
for Striga control due to the longer growing season in the zone.
The practice of soybean-maize rotation was also negatively associated
with Striga count (R = -0.57**) and Striga score (R = -0.40*)
and intercropping maize with cowpea was negatively correlated with Striga
score (R = -0.54*). Increasing N fertilizer rate was negatively associated
with Striga count (R = -0.64**) and score (R = -0.57**) and positively
associated with grain yield ha-1 (R = 0.86**), while more frequent
weeding was positively correlated with grain yield ha-1 (R
The maize varieties grown in SS were positively associated with Striga
count (R = 0.56**) and score (R = 0.59**), because all the varieties grown
were either tolerant or non-resistant and therefore allowed more Striga
plants to emerge and enhanced host damage (Table 4).
The maize variety 94 TZE Comp-5-W is Striga tolerant, the variety
95 TZEE-W is extra early, but neither tolerant nor resistant. The practice
of legume-cereal rotation in the zone was negatively correlated with Striga
count (R = -0.38*). Similarly, application of high rates of N fertilizer
was negatively associated with Striga count (R = -0.40*) and host
damage score (R = -0.54*) and positively correlated with grain yield ha-1
(R = 0.84**). Weeding frequency was negatively associated with grain yield
ha-1, probably due to the negative correlation observed between
weeding frequency with Striga count (R = -0.49*) and host damage
score (R = -0.65**).
Some of the farmer practices surveyed such as use of a resistant variety,
applying 100 kg N ha-1, legume-cereal rotation and 3-hoe weedings
may have been integrated, as each was highly effective in reducing Striga
infestation and increasing grain yield ha-1. Kim (1994) suggested
that the ideal management for Striga control for resource poor
farmers in Africa would be a soybean-maize rotation system, whether intercropping
or rotation, choosing high yielding maize that is tolerant or resistant
to Striga and has combined resistance to other major biotic stresses.
The choice of an integrated Striga control package will depend
on the level of severity of Striga infestation. In highly infested
areas, Parker and Riches (1993) suggested growing a resistant variety,
but when such a variety is not available, land fallowing or legume-cereal
rotation for at least 3 years was recommended.
Dogget (1991) also suggested host plant resistance combined with improved
soil fertility management or cereal-legume rotation and intercropping
in which the legume acts as a trap crop. Schulz et al. (2003) and
Ellis-Jones (2004) demonstrated on a small scale the agronomic and economic
potential of an integrated Striga control package under farmer-managed
conditions in northern Nigeria. Similar packages can be demonstrated in
combination with soil fertility management under farmer conditions to
reduce Striga infestation, reverse land degradation and improve
crop production in the savanna zones of northeast Nigeria.
Farmers in the savanna zones of northeast Nigeria have diverse crop management
practices that influence Striga infestation. The main farmer practices
promoting Striga infestation in maize fields are prolonged period
of land use, growing local or Striga tolerant maize varieties,
continuous mono cropping of maize, inadequate or no N fertilization, early
planting and poor farm sanitation. Consequently, growing Striga
resistant maize varieties, using legume-maize rotation, relay intercropping
of maize + legumes, late planting, adequate N fertilization and two or
three hoe weedings would reduce Striga infestation, reverse land
degradation and increase maize grain yield in the study area. These could
serve as component technologies in an integrated Striga control
package for combating the menace of the weed species in the region.
The study was sponsored by PROSAB, a CIDA-funded project. The authors
appreciate funding assistance from the project management and field assistance
from extension agents and the participating farmers in the nine communities.
The views expressed are not necessarily those of CIDA or PROSAB.
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