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Influence of phosphorus on the performance of cowpea (Vigna unguiculata (L) Walp.) varieties in the Sudan savanna of Nigeria

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Savanna regions of Nigeria are deficient in ni-trogen and phosphorus, which retard the growth and yield of crops. Therefore, a study was conducted in the wet season of 2006 at the Dry Land Teaching and Research Farm of Us-manu Danfodiyo University, Sokoto to evaluate the effect of phosphorus on the growth and yield of two cowpea varieties sourced from Republic of Niger. Treatment consisted of four (4) rates of phosphorus (0, 20, 40, 60 kg·ha –1) factorialy combined with (2) varieties of cowpea (KVX303096G and TN5-78) and laid out in a randomized complete block design (RCBD) rep-licated three (3) times. Results showed signifi-cant response to applied P on pods per plant, grain and stover yield and 100-seed weight with highest response to the application of 60 kg P ha –1 . From this study it can be concluded that KVX303096G and TN5-78 could both be sown under Sokoto condition to obtain reasonable yield of about 1 t·ha –1 of grain and 1.6 t·ha –1 of stover. Irrespective of the varieties, application of 60 kg P 2 O 5 ha –1 could be recommended for higher yield of cowpea (1.4 t·ha –1) relative to 0 kg P/ha that yielded 1.0 t·ha –1 .
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Vol.2, No.3, 313-317 (2011)
doi:10.4236/as.2011.23042
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/AS/
Agricultural Sciences
Influence of phosphorus on the performance of cowpea
(Vigna unguiculata (L) Walp.) varieties in the Sudan
savanna of Nigeria
A. Singh1*, A. L. Baoule1, H. G. Ahmed1, A. U. Dikko2, U. Aliyu1, M. B. Sokoto1, J. Alhassan1, M.
Musa1, B. Haliru1
1Department of Crop Science, Usmanu Danfodiyo University, Sokoto, Nigeria; *Corresponding author: ajitsingh66@yahoo.com,
asingh@udusok.edu.ng
2Department of Soil Science and Agricultural Engineering, Usmanu Danfodiyo University, Sokoto, Nigeria.
Received 28 March 2011; revised 24 May 2011; accepted 21 July 2011.
ABSTRACT
Savanna regions of Nigeria are deficient in ni-
trogen and phosphorus, which retard the
growth and yield of crops. Therefore, a study
was conducted in the wet season of 2006 at the
Dry Land Teaching and Research Farm of Us-
manu Danfodiyo University, Sokoto to evaluate
the effect of phosphorus on the growth and
yield of two cowpea varieties sourced from
Republic of Niger. Treatment consisted of four
(4) rates of phosphorus (0, 20, 40, 60 kg·ha–1)
factorialy combined with (2) varieties of cowpea
(KVX303096G and TN5-78) and laid out in a
randomized complete block design (RCBD) rep-
licated three (3) times. Results showed signifi-
cant response to applied P on pods per plant,
grain and stover yield and 100-seed weight with
highest response to the application of 60 kg P ha–1.
From this study it can be concluded that
KVX303096G and TN5-78 could both be sown
under Sokoto condition to obtain reasonable
yield of about 1 t·ha–1 of grain and 1.6 t·ha–1 of
stover. Irrespective of the varieties, application
of 60 kg P2O5 ha–1 could be recommended for
higher yield of cowpea (1.4 t·ha–1) relative to 0 kg
P/ha that yielded 1.0 t·ha–1.
Keywords: Cowpea [Vigna Unguiculata (L.) Walp.];
Phosphorus; Sudan Savanna; Nigeria
1. INTRODUCTION
Cowpea (Vigna unguiculata (L.) Walp.) is an important
grain legume in the dry savanna of the tropics covering
12.5 million hectares with annual production of about
3.3 million tones [1]. Nigeria is the world’s largest
producer with 2.1 million tones followed by Niger with
650,000 tones and Mali with 110,000 tones [2]. About
64% of the area under cowpea is grown in central and
east Africa. Cowpea is mostly cultivated in mixture with
others crops such as millet and sorghum mostly in
Sahelian and Sudan region.
Cowpea is well adapted to poor fertility and low
rainfall conditions. Cowpea grows best on fertile, loam
soils with rainfall of 760 - 1520 mm during the growing
period, and thrives best on dry areas of Northern part of
Nigeria and transported to the Southern part of Nigeria
[3]. Cowpea is an important crop because of its role in
human and livestock nutrition. It reduces the shortage of
food by making efficient use of water and nutrient. It is a
source of protein and also less expensive than meat.
Cowpea is of vital importance to the livelihood of
several million of people in east and central Africa [4].
Cowpea is an important legume crop in the dry savannas
of Africa, especially West Africa. Out of the 12.5 million
hectare cultivated to cowpea worldwide, Singh et al. [5]
estimated that eight million hectare are in West and Cen-
tral Africa, distributed predominantly between Nigeria
and Niger. In spite of the fact that grain yields are low,
cowpea has continued to be a popular crop among
farmers. This is because cowpea provides high protein
food for people, especially children; it improves and
sustains soil fertility, and provides high quality fodder
for livestock [6,7]. Cowpea contributes to the improve-
ment of soil fertility by the fixation of nitrogen (N) in
the soil (60 - 70 kg·N·ha–1 to the subsequent crop) [8].
The result obtained from a research work carried by IITA
[9] showed that cowpea fixed 240 kg·ha–1 of N. The crop
provides a high proportion of its own requirement,
besides leaving a fixed N deposit in the soil of up to 60 -
70 kg·ha–1. In addition to its role-played in mixture with
cereals, the crop is advantageous in terms of weed
A. Singh et al. / Agricultural Science 2 (2011) 313-317
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/AS/
314
control, soil cover, protection from soil erosion and
dispersal of insects [10].
Phosphorus (P) is among the most needed elements
for crop production in many tropical soils. However,
many tropical soils are P-deficient [11]. Phosphorus,
although not required in large quantities, is critical to
cowpea yield because of its multiple effects on nutrition
[12]. All growing plants require P for growth and
development in significantly large quantity. P deficiency
is the most limiting soil fertility factor for cowpea
production [10]. Phosphorus although not required in
large quantities is critical to cowpea yield (particularly
for improved photoperiod-insensitive cultivars) because
of its multiples effects on nutrition. It not only increases
seed yields but also nodulation. Others workers have
reported that phosphorus application influences the
content of others nutrients in leaves [13] and seed. The
deficiency can be so acute in some soils of the savanna
zone of western Africa that plant growth ceases as soon
as the P stored in the seed is exhausted [14]. Because of
its multiple effects on plant nutrition (not only on
nodulation), a phosphorus fertilizer is recommended to
increase yields (P2O5: 20 - 60 kg·ha–1) [10]. Smyth and
Cravo [15] working on Xanthic Hapludox near Manaus,
Brazil reported that for cowpea critical levels for soil P
was 60 kg·P·ha–1.
Despite the importance of cowpea in human diet and
feed for animals, the yield obtained by most farmers is
very low. In Nigeria the average yield per hectare in the
respective years were 0.75 t·ha–1 in 1990, 0.72 t·ha–1 in
1991, 0.51 t·ha–1 in 1992, 1993 and 1994, 0.49 t·ha–1 in
1995, 0.45 t·ha–1 in 1996, 0.48 t·ha–1 in 1997, 0.41 t·ha–1
in 1998, 0.42 t·ha–1 in 1999, 2000, 2001 and 2002; 0.43
t·ha–1 2003 and 2004 [16]. Because of the rapid increase
in population, there is a high demand for food and
therefore, there is a need to augment the production of
cowpea. N is not critical for legumes because legumes
fix atmospheric N2 through symbiotic association with
strains of Rhizobium sp. Phosphorus is the second most
important nutrient after N and could be used to increase
production of cowpea as most soils in the tropics are P
deficient. Phosphorus is known to increases the yield of
cowpea by increased N2 fixation through nodulation and
utilization of N fertilizer [10]. Thus, this study was con-
ducted to evaluate the effect of phosphorus fertilizer on
yield of cowpea and select cowpea variety responsive to
phosphorus application.
2. MATERIALS AND METHODS
The experiment was conducted in 2006 cropping
season at the dry land farm of Usmanu Danfodiyo
University, Sokoto. Sokoto is located on latitude 13˚01
N and at longitude 05˚15 E and lies at an altitude of 350
m above the sea level. It falls in Sudan Savanna agro-
ecological zone. The rainfall starts mostly in June and
ends in October with a mean annual rainfall of about 350
- 700 mm. The maximum and minimum temperature of
Sokoto ranges from 40 to 15˚C, respectively [17]. The
treatments consisted of factorial combinations of four (4)
levels of phosphorous (0, 20, 40 and 60) and twovarieties
of cowpea (KVX303096G and T5-78) (8 treatment
combinations) laid out in a randomized complete block
design (RCBD) replicated 3 times.
The seeds of cowpea varieties were obtained from the
research institute of Niger Republic known as INRAN in
Tahoua State and sown on the 18th of June, 2006. Two
seeds were sown per hill at a depth of 3 - 4 cm and 75
cm apart at a plant-to-plant spacing of 50 cm within a
row. Urea at the rate 15 kg·ha–1 was applied as a starter
dose to all the plots while P2O5 was applied as per
treatment (0, 20, 40, and 60 kg P2O5 ha–1). Weeding was
carried out twice manually at 5 and 8 weeks after sowing.
The plots were sprayed with karate (Lambda cyhorlothrim)
to take care of Aphis craccivora. Harvesting was done
manually at physiological maturity when the pods had
turned yellowish brown.
Data collected on yield parameters were subjected to
analysis of variance (ANOVA) technique using Statisti-
cal Analysis System (SAS) [18]. Significant different
between treatments were further analyzed using least
significant different test (LSD) for mean separation.
3. RESULTS AND DISCUSSION
3.1. Physico-Chemical Properties of the Soil
The general chemical and physical properties of the
surface soils (0 - 15 cm) used for the field experiments
are presented in Table 1. Soils at the experimental site
were largely Sandy and the soil pH (H2O) was moder-
ately acidic (6.5). The organic carbon (OC), total N and
available P in the soil was very low while exchangeable
K in the soil at the experimental site was low. The total
annual rainfall at the experimental site was 604 mm with
peak in August. The rain established in June and ceased
in October coinciding with sowing and harvesting of
cowpea, respectively (Figure 1).
Table 1. Physico-chemical characteristic of the soil at the ex-
periment site.
Parameters Value Remarks
Texture Sandy
pH in water 6.50 Mod. acidic
pH in CaCl2 6.19
Total phosphorus (P) (mg·kg–1) 1.80 Very Low
Organic carbon (g·kg–1) 1.58 Very Low
Total nitrogen (N) (g·kg–1) 0.65 Very low
Exchangeable potassium (K) (cmol·kg–-1) 0.65 Low
A. Singh et al. / Agricultural Science 2 (2011) 313-317
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/AS/
315315
Figure 1. Monthly rainfall pattern and total annual
rainfall at the Experimental site. (Source: Energy Re-
search Center, Usmanu Danfodiyo University, Soko-
to).
Table 2. Effect of variety and phosphorus on the number of
pods per plant and seeds per pod.
Treatment Pods per plant Seeds per pod
Variety (V)
KVX303096G 52 ± 6.8 9.7 ± 2.8
TN5-78 49 ± 8.4 10.8 ± 3.8
SE 2.1 0.51
Significance level ns ns
Phosphorus (P)
0 43 ± 8.3b 11.1 ± 1.8
20 50 ± 7.8ab 9.9 ± 1.2
40 54 ± 3.4a 10.3 ± 2.4
60 54 ± 3.2a 9.7 ± 1.8
SE 2.9 0.73
Significance level s ns
Interaction
V × P ns ns
3.2. Number of Pods per Plant and Seeds
per Pod
There was no significant effect of the variety on the
number of pods per plant. However, variety KVX303096
G recorded higher number of pods per plant (52) than
the variety TN5-78 (49) (Table 2). Phosphorus had
significant (P < 0.05) effect on the number of pods per
plant. Significantly (P < 0.05) higher pods per plant
were recorded in plots applied with 40 (54) and 60 (54)
kg P ha–1 than 0 (43) and 20 (50) kg P ha–1 (Table 2).
This could be due to higher level of P in those plots.
Mokwunye and Bationo [19] have reported that, P is
essential for photosynthesis, pod development and grain
filling in leguminous crops. P is responsible for nodu-
lation in cowpea. Thus higher nodulation resulted in
higher nitrogen fixation and eventually the number of
pods per plant. There was no significant effect of
interaction of variety and phosphorus on pods per plant.
The results of the present study are higher than that
recorded by Okeleye et al. [20] where the number of
pods per plants obtained ranged from 7.3 to 30.8 by ap-
plying a rate of 20 and 30 kg P ha–1 using short and me-
dium duration cowpea varieties.
Both the variety and phosphorus had no significant
effect on the number of seeds per pod. Statistically simi-
lar seed number per pod was recorded in variety TN5-78
(10.8) and KVX303096G(9.7). Interaction between vari-
ety and phosphorus had no significant effect on the num-
ber of seeds per pod.
3.3. Grain and Stover Yield
There was significant effect of phosphorus on the
stover yield of cowpea. Similar to the grain yield, sig-
nificantly (P < 0.05) higher stover yield was recorded in
plots supplied with 60 (2115 kg·ha–1) than with 0 (1411
kg·ha–1), 20 (1482 kg·ha-1) and 40 kg P2O5 ha–1 (1571
kg·ha–1). This could again be attributed to the availability
of P that would have increased the intensity of nodula-
tion and thus nitrogen fixation. Higher nitrogen fixation
would result in higher yield of the crop. Interaction be-
tween phosphorus and variety had no significant effect
on the stover yield of cowpea.
Variety had no significant effect on the grain yield of
cowpea. Statistically similar grain yield was recorded in
both KVX303096G (1120 kg·ha–1) and TN5-78 (1074
kg·ha–1) (Table 3). This indicated the similar performance
of the two varieties under Sokoto agro-ecology.
There was significant (P < 0.05) response to applied P
on the grain yield of cowpea. Significantly higher grain
yield was recorded in plots applied to 60 (1353 kg·ha–1)
than 0 (1017 kg·ha–1), 20 (1067 kg·ha–1) and 40 kg P ha–1
(951 kg·ha–1). Application of 20 and 40 kg P2O5 ha–1 was
Table 3. Effect of variety, phosphorus and their interaction on
the grain and stover yield of cowpea.
Va ri e t y P levels
(kg·ha–1)KVX303096G TN5-78
Mean phosphorus
levels (Main effect P)
Grain yield (kg·ha-1)
0 928 ± 239 b 1106 ± 188 ab 1017±216 b
20 1165 ± 179 ab 968 ± 218 b 1067±209 b
40 914 ± 82 b 988 ± 298 b 951±200 b
60 1472 ± 266 a 1235 ± 61 a 1353±216 a
Means
Va ri e t y 1120 ± 294 1074 ± 211
SE SEVar i e t y = 62.6; SEphosphorus = 88.6;
SEVariety × Phosphorus = 125.28
Stover yield (kg·ha1)
0 1314 ± 261 1509 ± 522 1411 ± 384 b
20 1753 ± 665 1546 ± 202 1649 ± 454 ab
40 1595 ± 416 1881 ± 539 1738 ± 458 ab
60 2072 ± 265 2158 ± 284 2115 ± 250 a
Means
Va ri e t y 1684 ± 468 1773 ± 449
SE SEVar i e t y = 100.1; SEphosphorus = 141.5;
SEVariety × Phosphorus = 259.9
Values following ± are standard deviation of the means. Means in a column
for Phosphorus and across row and column for variety x P interaction fol-
lowed by same letter (s) are not significantly different at 5% level, ns = Not
significant, *Significant at 5% level.
A. Singh et al. / Agricultural Science 2 (2011) 313-317
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/AS/
316
not different from those plots that were not applied with
P (0 kg P ha–1). This indicated that P became a limiting
factor at later stage of plant growth. Higher yield re-
corded with 60 kg·ha–1 was attributed to higher avai-
lability of P that is responsible for effective nodulation
in cowpea. Okeleye and Okelana [21] also observed sig-
nificantly increased nodulation, grain yield, and total dry
matter for cowpea varieties in response to P application.
Variety had no significant effect on the stover yield of
cowpea as both varieties recorded 1600 kg·ha–1 of cow-
pea stover (Table 3).
There was significant effect of phosphorus on the
stover yield of cowpea. Similar to the grain yield,
significantly (P < 0.05) higher stover yield was recorded
in plots supplied with 60 (2115 kg·ha–1) than with 0
(1411 kg·ha–1), 20 (1482 kg·ha–1) and 40 kg P2O5 ha–1
(1571 kg·ha–1). This could again be attributed to the
availability of P that would have increased the intensity
of nodulation and thus nitrogen fixation. Higher nitrogen
fixation would result in higher yield of the crop. In-
teraction between phosphorus and variety had no sig-
nificant effect on the stover yield of cowpea.
3.4. Harvest Index and 100-Seed Weight
Harvest index is the proportion of grain in the total
aboveground biomass of the crop expressed in percent-
age and it ranged from 36% to 40%. This indicated that
only 36% to 40% of the photosynthate was translocated
to the grain. Variety did not have significant influence on
the HI of the crop. KVX303096G recorded statistically
(P > 0.05) similar HI with TN5-78 variety (Table 4). P
also did not have significant influence on the HI of the
crop implying that HI is a genetic trait and will only be
influenced by variety differences. Effect of interaction
between variety and phosphorus was not significant
(Table 4).
There was no significant effect of variety on the hun-
dred seeds weight (Figure 2). The two varieties recorded
similar 100-seed weight of about 20.2 g. Effect of phos-
phorus on 100-seed weight was significant (P < 0.05)
Table 4. Effect of variety, phosphorus and their interaction on
harvest index of cowpea.
Harvest index (%) P levels
(kg·ha–1) KVX303096G TN5-78
Mean phosphor-
rus levels
0 41.2 ± 1.8 43.0 ± 6.6 42 ± 4.4
20 40.9 ± 6.4 38.4 ± 6.9 40 ± 6.1
40 37.0 ± 5.7 35.2 ±13.7 36 ± 9.4
60 41.4 ± 1.4 36.6 ± 3.7 39 ± 3.7
Means Variety 40.0 ± 4.2 38.0 ± 7.9
SE SEVar i e t y = 2.10; SEphosphorus = 2.97;
SEVariety × Phosphorus = 4.196
Values following ± are standard deviation of the means.
Figure 2. Main effect of variety on 100-seed weight of
cowpea.
Figure 3. Main effect of phosphorus levels on 100-
seed weight of cowpea. Bars with same letter (s) are
not significantly different using LSD at 5% level.
Table 5. Interaction effect of variety x phosphorus on 100-
grain weight of cowpea.
100-grain weight (g) Phosphorus levels
(kg·ha-1) KVX303096G TN5-78
0 18.32 ± 0.06 b 18.59 ± 0.54 b
20 20.51 ± 1.05 a 20.60 ± 0.23 a
40 21.50 ± 0.57 a 20.54 ± 0.93 a
60 20.30 ± 0.73 a 20.98 ± 1.31 a
SE 0.439
Values following ± are standard deviation of the means. Means across rows
and columns followed by same letter (s) are not significantly different using
LSD at 5% level.
with 40 kg·ha–1 (54.17 g) and 60 kg·ha–1 (54.17 g)
recording significantly higher 100-seed weight than 0 kg
P ha–1 (42.83 g) (Figure 3). The interaction of variety
and phosphorus on 100-grain weight of cowpea was
significant (Table 5). For both variety KVX303096G and
TN5-78, application of 20, 40 and 60 kg P ha–1 resulted
in similar 100-grain weight (Table 5). For all levels of P
including control, the two varieties were at par. These
results coincide with the results recorded by Okeleye et
al. [20] where the weight of 100 seed of cowpea ranged
A. Singh et al. / Agricultural Science 2 (2011) 313-317
Copyright © 2011 SciRes. http://www.scirp.org/journal/AS/
317317
from 13.50 to 39.7 g by the application of 20 and 30 kg
P ha–1. Phosphorus intervenes in the formation of seed
and improves seed quality [21].
Openly accessible at
4. CONCLUSIONS
From this study it can be concluded that KVX303096G
and TN5-78 could both be sown under Sokoto condition
to obtain reasonable yield of about 1 t·ha–1 of grain and
1.6 t·ha–1 of stover. Irrespective of the varieties, applica-
tion of 60 kg P2O5 ha–1 could be recommended for higher
yield of cowpea (1.4 t·ha–1) relative to 0 kg P2O5 ha–1
that yielded 1.0 t·ha–1. However, 60 kg P2O5 ha–1 may not
be the optimum as further application of P may or may
not increase the yield of cowpea. Therefore it is subject
to investigation.
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... Despite theimportance of the crop in the region, the yield is very low (Singh et al., 2011). This could be because of adoption of inappropriate varieties and improper weed control methods by the farmers. ...
... The lack of significant difference among the varieties despite their differences in total dry weight does not come as a surprise since in the semi-arid tropics crop yields are sometimes not predictable. Singh et al.(2011) reported that varietyhad no significant (p>0.05) effect on the herbage yield of cowpea. ...
... Thoughtful application of P fertilizer to legumes is geared towards improving not only their growth and yield, but also nitrogen fi xation. Earlier researchers have noted the eff ect of genotype and phosphorus levels on growth and productivity of cowpea in diff erent agro ecological zone (Singh et al. 2011, Chauhan et al. 2016, Pardhi 2016. However, there is insuffi cient research work on impact of diff erent P levels on cowpea genotypes under agro-climatic zone 28 (Madhupur Tract). ...
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Phosphorus (P) plays an important role on yield and yield contributing characters of cowpea. A field experiment was conducted at the Agronomy research field of Bangabandhu Sheikh Mujibur Rahman Agricultural University to evaluate the effects of different P levels on yield and yield attributes of cowpea genotypes. Four cowpea genotypes, viz. BARI Felon-1, A-06008, VI046192 and VI034386 were tested under four levels of P viz. 0, 30, 60, 90 kg ha-1. The experiment was laid out in a factorial randomized complete block design with three replications. The results indicated that among the cowpea genotypes, the highest plant height (93.08 cm), number of leaves plant-1 (29.75), number of branches plant-1 (6.31), were obtained from BARI Felon-1, while the genotype A-06008 gave the highest number of pods plant-1 (2.62), number of seeds pod-1 (13.46) and grain yield (624.73 kg ha-1). Application of P at 90 kg ha-1 showed the highest number of branches plant-1 (5.70), number of pods plant-1 (1.55), number of seeds pod-1 (12.76) and grain yield (339.28 kg ha-1). In terms of yield, the cowpea genotype A-06008 showed the best performance at a P level of 90 kg ha-1 .
... De acordo com Singh et al. (2011), para a cultura do feijão, o fósforo fornece reações frequentes, sua disponibilidade no solo aumenta a intensidade dos nódulos, para fixar nitrogênio e, assim, aumentar a produtividade, mas sua deficiência terá um impacto negativo no crescimento e produção da planta. De acordo com Nyoki e Ndakidemi (2013), reconheceu a importância do fósforo na melhoria do estado nutricional das leguminosas, pois melhora a eficiência da simbiose de rizóbios e leguminosas, aumentando nódulos, rendimento e produtividade do feijão. ...
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O feijão (Phaseolus vulgaris) é o principal alimento consumido no Brasil. Tal importância é dada pelo que possui alto valor nutricional, fornecendo nutrientes para consumo humano, principalmente ferro e carboidratos. A maioria dos solos brasileiros apresenta baixo nível de fósforo disponível, sendo considerado uma das principais limitações para sua produção, sendo assim exigente no aumento de nutrientes durante o cultivo, seja por meio da fertilização do solo ou foliar. O presente trabalho objetivou-se avaliar a aplicação via solo e foliar de fósforo no tratamento de sementes e nos estádios fenológicos, combinados ou não na cultura de feijão preto e branco na Região dos Campos Gerais -PR. O delineamento foi em blocos casualizados com 5 níveis de tratamento e 3 repetições, cujas parcelas foram compostas por 5 linhas de feijão com 1,5 metros de comprimento e espaçadas por 0,45m, totalizando 4,5 m². Foram avaliados o rendimento de grãos (umidade corrigida para 13%), componentes do rendimento (número de vagens, número de grãos, massa de grãos por planta e massa de mil grãos), estatura de plantas e análise nutricional do fósforo na parte aérea. Resultou-se que o tratamento com MAP purificado apresentou vantagens em relação a fatores como número de vagens, peso do grão, produtividade, massa de 1000 grãos e diâmetro do caule, mas não apresentou resultados significativos nesses pontos. Consequentemente conclui-se que, o objetivo foi alcançado, pois foi possível avaliar visualmente o efeito que a aplicação foliar de fósforo terá na produtividade e na qualidade fisiológica e tecnológica dos grãos de duas cultivares.
... Additionally, it was shown that the soil formed from Basalt might lose some of its ability to bind P when organic molecules were introduced through the treatments. The intensity of P adsorption decreased when chicken dung as compost was added to soils originating from granite and river alluvial deposits but rose following the application of organic fertilizer [65][66][67][68]. The three adsorption isotherm equations for basalt-derived soils all fit well. ...
Article
Over two-thirds of the soils in the world suffer from phosphorus shortages (P). Due to phosphorus being unavailable to all but a small portion of plants, agricultural productivity diminishes. Phosphorus-deficient soils have traditionally been fertilized in order to decrease the severity of the environmental impact. Improving agricultural management practices for sustainable crop output, including reduction in phosphorus loss in terms of runoff, is the emphasis of this study. Investigating chemical fractionation mechanisms to distinguish between occluded P, acid-extractable calcium-bonded P, and non-occluded P is necessary for increasing inorganic phosphorous (Pi) in mung bean (Vigna radiata) types and establishing net grazing systems. Phosphate (P) is known to be transferred between pools due to weathering, with the highest P retention rates found in clay-rich soils. Soil with a finer texture is better able to absorb and fix phosphorus, which means more nutrients and water can be made available to the plant when mungbean varieties are inoculated into it. More photosynthesis means more accumulated dry stuff. The P-treated variety of mungbean had the greatest yield index (13.28). Pods per plant (46.02), pods per crop (8.20), test weight (40.63 gm), pod weight (8.0 g), and seed weight (1.0 g) were all significantly increased when fertilization done with Diammonium phosphate (DAP). An increase in nodule count, leaf area index, plant height, grain yield, total chlorophyll content, and straw output of up to 40% was observed at higher P2O5 concentrations (2988 kilograms per hectare). Each plant developed the maximum number of nodules after receiving injections of Phosphate solubilizing bacteria (PSB) and Aspergillus awamori. Its plants were the biggest and most productive overall, and its leaves contained the highest concentrations of chlorophyll. In acidic piedmont soil, liming increased mungbean yields by adjusting other chemical properties and boosting pH. They contend that expanding India's production of pulses is essential for the country to eventually achieve food security. P nutrition needs to be incorporated into farmers' and extension workers' balanced nutrient management programs if they wish to see higher quality pulse yields and greater long-term profitability.
... A study reported phosphorus requirement of cowpea in southern and the extreme northern part of Nigeria, respectively (Kang and Osiname, 1979;Singh et al., 2011a). Increasing cowpea production by the smallholder farmers in the southern Guinea Savanna of Nigeria, calls for the search for organic fertilizers to improve cowpea cultivation. ...
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Organic amendment has a great potential to increasingly replace the use of mineral fertilizer and pesticide for sustainable crop production. A screen house experiment was conducted to evaluate the effects of organic amendments on the growth of two cowpea varieties with and without mycorrhiza inoculation. The experiment was a completely randomized design and a factorial combination of two cowpea varieties (IT99K-573-1-1 and Oloyin), two levels of inoculation with mycorrhiza (with and without) and five levels of organic amendments (formulated from palm kernel cake, oil palm empty fruit bunch ash, plantain peels and Tithonia). Each treatment combination had six replicates. Organic amendments were incorporated two weeks before planting of cowpea seeds and inoculation of mycorrhiza to the soil. Data were collected on cowpea growth attributes such as the number of leaves, number of branches, plant height, stem girth and leaf area. Data were subjected to analysis of variance using the GenStat Discovery Edition 4 and treatment means were separated using the Duncan's Multiple Range Test at α0.05. Organic amendment 5 (control) was best in terms of mean values for number of leaves, number of branches and plant height. Cowpea plants inoculated with mycorrhiza were best for all growth attributes. In the residual experiment, Oloyin variety with organic amendment 3, previously inoculated with mycorrhiza and had the highest mean number of leaves and oloyin variety with organic amendment 4 not previously inoculated with mycorrhiza and had the highest mean plant height. Therefore, we need to transform and use some of the agricultural waste that are rich in nutrient particularly in phosphorus as a source of organic fertilizer for cowpea cultivation.
... This shows that the chicken manure was easily available and in a very good condition to be easily absorbed by the plant roots, which is why there was so much growth in the plant. A group researchers reported that organic manures especially poultry manure could increase the plant height of cowpea when compared with another source of manure (Singh et al., 2011). ...
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The experiment was carried out at the field of Nepal Polytechnic Institute (NPI), Bharatpur, Chitwan. The purpose of the research was to study the effect of different sources of organic manure in the growth and yield of cowpea (Vigna unguiculata L) and the chemical properties of soil. The experiment was laid out by using 5 treatments and four replications in Randomized Complete Block Design (RCBD). There was a total of 20 plots each of 2 x 2 m2. The variety used was Malepatan-1. Poultry manure, goat manure, Farmyard Manure (FYM), mustard cake, and RDF, were tested as treatments. The soil of the experimental plot was acidic (pH 6.1) containing low total nitrogen (0.7), low available potassium (90.32), low available phosphorous (13.99), and medium organic manure (2.9). The data on vegetative parameters (plant height, number of leaves per plant, number of branches per plant), yield attributing parameters (number of flowers per plant, number of pods per branches, and yield), and soil chemical properties (total nitrogen, available phosphorus, available potassium, pH and organic matter) were taken and entered in Ms-Excel which were then subjected of analysis of variance using Genstat and means were separated using DMRT. Out of 5 treatments treatment poultry (2.620kg/plot) was superior and significantly increased plant height, number of leaves, number of branches, number of pods, and yield. While mustard oil cake was ineffective to give optimum yield and yield attributing characters. The highest yield was obtained from treatment poultry manure i.e. (8.438 ton/ha) while the lowest yield was obtained from the treatment mustard oil cake (2.906 ton/ha).
... Phosphorus is essential for cowpea production in many tropical African soils with the inherent low soil availability of phosphorus [71]. Cowpea does not require too much nitrogen fertilizer because it fixes its nitrogen from the air using the nodules in its roots [72]. ...
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Currently, the world population is increasing, and humanity is facing food and nutritional scarcity. Climate change and variability are a major threat to global food and nutritional security, reducing crop productivity in the tropical and subtropical regions of the globe. Cowpea has the potential to make a significant contribution to global food and nutritional security. In addition, it can be part of a sustainable food system, being a genetic resource for future crop improvement, contributing to resilience and improving agricultural sustainability under climate change conditions. In malnutrition prone regions of sub-Saharan Africa (SSA) countries, cowpea has become a strategic dryland legume crop for addressing food insecurity and malnutrition. Therefore, this review aims to assess the contribution of cowpea to SSA countries as a climate-resilient crop and the existing production challenges and perspectives. Cowpea leaves and immature pods are rich in diverse nutrients, with high levels of protein, vitamins, macro and micronutrients, minerals, fiber, and carbohydrates compared to its grain. In addition, cowpea is truly a multifunctional crop for maintaining good health and for reducing non-communicable human diseases. However, as a leafy vegetable , cowpea has not been researched and promoted sufficiently because it has not been promoted as a food security crop due to its low yield potential, susceptibility to biotic and abiotic stresses, quality assurance issues, policy regulation, and cultural beliefs (it is considered a livestock feed). The development of superior cowpea as a leafy vegetable can be approached in different ways, such as conventional breeding and gene stacking, speed breeding, mutation breeding, space breeding, demand-led breeding, a pan-omics approach, and local government policies. The successful breeding of cowpea genotypes that are high-yielding with a good nutritional value as well as having resistance to biotics and tolerant to abiotic stress could also be used to address food security and malnutrition-related challenges in sub-Saharan Africa.
... Shahid et al. [15] reported that seed production in soybean can increase by 70-75% when the proper bacterial strains is used to inoculate soybean seeds. Singh et al. [16] reported that higher nodulation due to inoculation led to higher N fixation by R and eventually the number of pods per plant which resulted to higher grain yields as a whole. ...
Article
Soybean (Glycine max [L.] Merrill) yields are far below the potential yield on most smallholder farms in Kenya. This necessitates suitable interventions to bridge this yield gap and result to profitable soybean production. An experiment was conducted in Chuka University demonstration farm, Chuka Sub County to determine the effect of integration of rhizobium inoculation (R) and phosphorus (P) on yields and net economic returns in soybean cultivation. The experiment was laid out in a randomized complete block design in a split-split plot arrangement with each treatment replicated three times. The experiment which was conducted between 2018 and 2019 was repeated once and the treatments included; three P rates (0, 20 and 30 kg/ha), three rhizobium rates (0, 100 and 200 g/ha) and two soybean genotypes (SB19 and SB24). Triple superphosphate (0:46:0) was used as the source of the phosphorus. The soybean genotypes, rhizobium and phosphorus rates were assigned to the main plot, sub-plot and the sub-sub plots respectively. Data collected included soybean yields (kg/ha) and economic analysis was calculated. The data collected was subjected to analysis of variance using Statistical Analysis System® 9.4 and significantly different means separated using Tukeys test at (p≤0.05). The results showed statistically significant difference in soybean yields and net economic benefit within SB19 and SB24 genotypes in both trials at (p≤0.05). Integration of R and P at the rate of 200 g and 30 kg/ha increased soybean yield by 101% and 98%, and 158% and 138% for SB19 and SB24 in trial I and II respectively. This earned a net economic benefit of ksh. 239,496 and 192,730, and ksh. 297,930 and 239,330 for SB19 and SB24 in both trials I and II, respectively. Both genotypes performed well in yield and net economic benefit and application of R and P at the rate of 200 g/ha and 30 kg/ha promoted yield and net economic benefit of soybean.
... This shows that the chicken manure was easily available and in a very good condition to be easily absorbed by the plant roots, which is why there was so much growth in the plant. A group researchers reported that organic manures especially poultry manure could increase the plant height of cowpea when compared with another source of manure (Singh et al., 2011). ...
Article
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The experiment was carried out at the field of Nepal Polytechnic Institute (NPI), Bharatpur, Chitwan. The purpose of the research was to study the effect of different sources of organic manure in the growth and yield of cowpea (Vigna unguiculata L) and the chemical properties of soil. The experiment was laid out by using 5 treatments and four replications in Randomized Complete Block Design (RCBD). There was a total of 20 plots each of 2 x 2 m 2. The variety used was Malepatan-1. Poultry manure, goat manure, Farmyard Manure (FYM), mustard cake, and RDF, were tested as treatments. The soil of the experimental plot was acidic (pH 6.1) containing low total nitrogen (0.7), low available potassium (90.32), low available phosphorous (13.99), and medium organic manure (2.9). The data on vegetative parameters (plant height, number of leaves per plant, number of branches per plant), yield attributing parameters (number of flowers per plant, number of pods per branches, and yield), and soil chemical properties (total nitrogen, available phosphorus, available potassium, pH and organic matter) were taken and entered in Ms-Excel which were then subjected of analysis of variance using Genstat and means were separated using DMRT. Out of 5 treatments treatment poultry (2.620kg/plot) was superior and significantly increased plant height, number of leaves, number of branches, number of pods, and yield. While mustard oil cake was ineffective to give optimum yield and yield attributing characters. The highest yield was obtained from treatment poultry manure i.e. (8.438 ton/ha) while the lowest yield was obtained from the treatment mustard oil cake (2.906 ton/ha).
Chapter
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Phosphorus is a major plant nutrient, yet phosphrus deficiency often limits plant growth and yield. There are four forms of phosphorus in the soil such as organic ohosphorus, soluble mineral ions of H2PO4− and HPO42−, soluble or adsorbed ions, and primary minerals. Phosphorus availability is controlled by climate, soil texture, and cultivation. The quantity of soluble mineral phosphorus in soil is usually low, and even when P fertilizers are added, phosphorus has a tendency to become less soluble. There are three main kinds of phosphorus fertilizers: biological, organic and chemical fertilizers. Phosphorus may also added in nanoparticles. Rock phosphate is a natural and cheap, and suits acid soils. In alkaline conditions, phosphorus is commonly unsoluble, unless amendments such as sulfur, organic matter, or phosphorus solubilizing bacteria are added to improve phosphorus bioavailability. Overall, agricultural management practices are important for increasing phosphorus availability for crops.KeywordsPhosphorus fertilizersRock phosphatePhosphorus deficiencyPhosphorus availabilityPhosphorus-solubilizing bacteria
Chapter
This book contains 23 peer-reviewed papers presented during the 'International Symposium on Balanced Nutrient Management Systems' which was held between 9 and 12 October 2000 in Cotonou, Republic of Benin. This book is presented in seven sections (i) general introduction; (ii) variability on physical and socioeconomic factors and its consequences for selection of representative areas for integrated nutrient management (INM) research; (iii) soil processes determining nutrient dynamics, particularly N and P; (iv) interactions between organic and mineral nutrient sources; (v) improved utilization of rock phosphate; (vi) decision support systems to improve resource use at farm level: on-farm testing of improved technologies; and (vii) recommendations. The currently accepted INM approach advocates the use of organic resources and mineral fertilizer inputs to redress nutrient depletion and sustain crop production. It also ensures that development of nutrient management strategies is problem-driven and involves farmers that are the end-users of such technologies.
Chapter
Phosphorus deficiency in tropical African soils is a major factor that reduces food prouction in the region. In some soils of the savanna zone of western Africa, the deficiency is so acute that plant growth ceases as soon as the phosphorus stored in the seed is exhausted.
Article
A field experiment was conducted for 2 years (1991 and 1992) at Abeokuta, south-west of Nigeria, to investigate the effect of phosphorus application (0, 30 and 60 kg P/ha) on nodulation, dry-matter accumulation and grain yield of 6 newly developed varieties of cowpea [Vigna unguiculata (L.) Walp.], viz 'IT 86D-1038', 'IT 86D-4982', 'IT 82D-699', 'IT 86D -27', 'IT 86D-M4' and 'IT 81D-1228'). Nodulation increased significantly in 'IT 86D-1038' from 202 at 0 kg P/ha to 225 at 30 kg P/ha. This significantly increased, the nodulation in other varieties too at 0-30 kg P/ha. Higher rate of P (60 kg P/ha) resulted in significantly higher nodulation in 'IT 82D-699' (184) and 'IT 86D-444' (188). The high P rate significantly reduced the number of days to 50% flowering by 5-8 days. The number of days to 50% flowering, unlike grain yield, was inversely related to P level in all the varieties. The grain yield of 'IT 86D-1038' was 1 082 kg/ha at 0 kg P/ha and 2 288 kg/ha at 60 kg/ha. Similar increase in yield was noted in other varieties tested, except in 'IT 86D-444', which gave its highest average yield of 2 423 kg/ha at 30 kg P/ha that decreased to 2 306 kg/ha at 60 kg P/ha.
Article
Phosphorus plays an important role for food crop production in the forest zone of tropical Africa but very little information is available on the phosphate requirement for maize production there. Field trials were, therefore, conducted with maize (Zea mays L.) at two locations on Alfisols in southern Nigeria to investigate the P response and the residual effect of applied P. The experimental sites were recently cleared from fallow and the vegetation was removed after land clearing. On the Egbeda soil (Oxic Paleustalf), which is derived from basement complex rocks, five seasons of maize croppings were done from 1971 to 1973 using a split-plot design with three replications. Four periods of fresh P applications (major and minor seasons 1971 and major and minor seasons 1972), formed the main plots and each of these fresh P applications consisted of five P rates (0, 26, 52, 78 and 104 kg P/ha) which made up the sub-plots. Maize culture T2A ✕ TZB was planted at a spacing of 75 ✕ 25 cm (53,300 plants/ha). The minor season maize received supplementary irrigation. On the Alagba soil (Oxic paleustalf) which is derived from sedimentary rocks, five P rates (0, 20, 40, 80, and 160 kg P/ha) were compared using a randomized complete block design with four replications. Phosphate was broadcasted as single superphosphate and incorporated in the soil to the various treatments. The residual effects of applied P were followed up at both locations. With removal of fallow vegetation following land clearing, significant responses to P applications were observed at both locations. The P requirement for obtaining significant yield increases was not very high, ranging from 26 to 52 kg P/ha depending on season and location. Higher yield response to P was observed during the main season (April to July) than during the minor season (August to November) planting. At both locations significant residual effects of applied P was observed on maize yield and Bray P-1 soil test levels. On the Egbeda soil it was possible to build up and maintain adequate amounts of extractable P for two to three maize crops with one addition between 52 to 104 kg P/ha. Good relationship was observed between maize grain yield and Bray P-1 test values on the Egbeda soil. The critical Bray P-1 test values was estimated to be about 14 ppm P. Results of incubation studies showed that under laboratory conditions 2.5 to 3 ppm of fertilizer P was required to increase the Bray P-1 test level by 1 ppm for the Egbeda and Alagba soils respectively. Under field conditions for the Egbeda soil the P rate required was estimated to be 3.5 ppm P. The critical P in the ear leaf was estimated at 0.3% P. High rate of P application was shown to depress the Zn status in the ear leaf. Please view the pdf by using the Full Text (PDF) link under 'View' to the left. Copyright © . .
Article
Phosphorus soil test interpretations in the Brazilian Amazon currently do not account for differences in P requirements among crops and lack information on the changes in available soil P per unit of applied fertilizer P. A long-term P experiment in a Xanthic Hapludox near Manaus, Brazil was used to determine soil and leaf P critical levels for corn (Zea mays L.) and cow pea (Vigna unguiculata L.). A total of six corn crops were planted in annual rotation with five crops of cowpea during five consecutive years. Critical levels were established by a segmented linear regression, a linear plateau, of relative crop yields on soil test or leaf P concentrations for each crop species. Mehlich 1 (1:10) critical P levels were 6 and 8 mg kg⁻¹ for corn and cowpea, respectively. Relationships between soil test P and crop yields were similar for fertilizer P placement as either broadcast and/or frequent bands. Fertilizer P required to raise the initial Mehlich 1 soil P to the critical levels were 41 and 60 kg P ha⁻¹ for corn and cowpea, respectively. Higher amounts of P were extracted by Bray 1 than by Mehlich 1, but both extractants were effective in relating available soil P to yield and applied fertilizer P. Critical foliar P concentrations for corn and cowpea were 1.6 and 1.8 g kg⁻¹, respectively. Higher soil and leaf P critical levels for cowpea relative to corn were attributed to greater P requirements for plants depending on symbiotic N2 fixation for their N supply. Joint contribution of the North Carolina Agric. Res. Serv. Journal Series no. 12071 and EMBRAPA/UEPAE de Manaus. This work was supported by EMBRAPA, the Potash & Phosphate Institute's Foundation for Agricultural Research, the Rockefeller Foundation and the U.S. AID. Please view the pdf by using the Full Text (PDF) link under 'View' to the left. Copyright © . .
Optimizing cultural practices for cowpea in Africa
  • N Muleba
  • H C Ezumah
Muleba, N. and Ezumah, H.C. (1985) Optimizing cultural practices for cowpea in Africa. In: Singh, S.R. and Rachie, K.O., Eds., Cowpea Research, Production, and Utilization, John Wiley and Sons Ltd, Chichester, 289-295.
Crop and farming systems
IITA (International Institute of Tropical Agriculture) (2003) Crop and farming systems. http://www.iita.org/crop/cowpea.htm
Phosphorous requirement of cowpea
  • B T Kang
  • M Naggos
Kang, B.T. and Naggos, M. (1983) Phosphorous requirement of cowpea. IITA Ibadan, Annual Report, 79-115.