COVERING LETTER
TITLE;
An Integrated Nutrient Management Approaches
for Improving Yield of Maize (Zea mays L.)
AUTHORS NAME AND ADDRESS
Naveed Iqbal
[E-mail :naveediqbal@yahoo.com]
Department of Agronomy, University of
Asghar Ali
[E-mail:draliuaf@hotmail.com]
Department of Agronomy, University of
Muhammad Ather Nadeem
[E-mail:drman@hotmail.com]
Department of Agronomy, University of
Muhammad Waseem
Corresponding Author
Department of Agronomy, University of
[E-mail:mianwaseem_1028@yahoo.com]
[+923349804812]
[waseem_1028@yahoo.com]
Agriculture,Faisalabad-38000, Pakistan
Agriculture,Faisalabad-38000, Pakistan
Agriculture,Faisalabad-38000, Pakistan
Agriculture,Faisalabad-38000, Pakistan
Muhammad Tahir
[E-mail:drtahirfsd@hotmail.com]
Department of Agronomy, University of
Mumhammad shahid Ibni Zamir
[[E-mail:zamir757@gmail.com]
Department of Agronomy, University of
Asif Iqbal
[E-mail:asifiqbal@yahoo.com]
Department of Agronomy, University of
Agriculture,Faisalabad-38000, Pakistan
Agriculture,Faisalabad-38000, Pakistan
Agriculture,Faisalabad-38000, Pakistan
1
An Integrated Nutrient Management Approaches
for Improving Yield of Maize (Zea mays L.)
Naveed Iqbal, Asghar Ali, Muahammad Ather Nadeem, Muhammad
Waseem, Muhammad Tahir, Mumhammad shahid Ibni Zamir and Asif
Iqbal
Department of Agronomy, University of Agriculture, Faisalabad, 38040, Pakistan.
Corresponding Arthur; [waseem_1028@yahoo.com]
ABSTRACT
A field study was conducted to evaluate the effect of integrated use of chemical
fertilizer (nitrogen) and compost on growth and yield of maize was conducted at
Agronomic Research Area, University of Agriculture, Faisalabad. The experiment
was laid out in randomized complete block design (RCBD) with four replications
having six treatment i.e. T1(Control),T2 (chemical fertilizer @ 250-120-125 NPK kg
ha-1),T3 (Compost alone @10 t ha-1),T4 ( 25% Nitrogen from compost + 75% Nitrogen
from chemical fertilizer),T5 (50% Nitrogen from compost + 50% Nitrogen from
chemical fertilizer)andT6(75% Nitrogen from compost + 25% Nitrogen from chemical
fertilizer ).Plant height, number of grain rows per cob, number of grains per row,
number of grains per cob and 1000-grain weight were significantly affected by all the
treatments. However grain yield, biological yield, harvest index and grain-pith ratio
significantly affected by compost and chemical fertilizer alone or in different
combination. The highest grain yield of 7.18t ha -1 was obtained with the application
of 25% Nitrogen from compost + 75% Nitrogen from chemical fertilizer.
Key words: maize; compost; chemical; integrated; nitrogen,
2
INTRODUCTION
Maize (Zea mays L.) is an important food and feed crop of the world. In Pakistan,
area under maize occupies third position after wheat and rice, 98% of which is
grown in Punjab and N.W.F.P. Basically it is a tropical plant but at present its
cultivation in subtropical and temperate regions is done extensively on world
wide bases. Maize is relatively short duration crop, capable of utilizing inputs
more efficiently and has capacity to produce large quantity of food grains per unit
area. It can successfully be cultivated twice a year as spring crop or autumn
crop. Maize has wider adaptability on global basis as its cultivation expands from
50o N to 40o S latitude and an altitude of 3,300 meter (Martin et al., 1976).
Maize grain has great nutritional value as it contains 72% starch, 10% proteins,
4.8% oil, 8.5% fiber, 3% sugar and 1% ash (Chaudhry, 1983).In Pakistan, maize
is grown on an area of 1,026 thousands hectares with the production of 3.313
million tones and average grain yield of 3264 Kg ha -1 (GOP, 2008). Grain yield
per unit area is low as compared to potential of the existing maize cultivars. Main
constraints to enhance maize productivity are suboptimal plant density,
inadequate nutrition such as nitrogen, inadequate water supply, weed infestation,
insect pest attack, etc.
The soils of Pakistan are generally low in organic matter, firstly because of arid
climate resulting in a rapid decomposition of organic matter and secondly, very
little organic matter is added to the soil. On an average most of soils of Pakistan
contain less than 1% organic matter. Soil fertility can be increased through the
utilization of mineral as well as organic materials (Azad and Yousaf, 1982; Malik,
2001).
Bending et al., (2002) concluded that crop residue and soil organic matter both
can affect the diversity of soil microbial community and increase the crop growth
and yield. Before the advent of chemical fertilizers, farmers mostly relied on
organic matter as the sole source to promote health and productivity of the soil.
Then the era of chemical fertilizers started and farmers neglected the use of
organic matter because chemical fertilizers were an effective substitute and a
ready source of nutrients.
3
Integrated use of chemical fertilizers and organic wastes may be an approach for
sustainable production of crops. This may improve the efficiency of chemical
fertilizers and thus reduce their use. Integrated use of organic wastes and
chemical fertilizers is beneficial in improving crop yield, soil pH, organic carbon
and available N, P and K in sandy loam soil (Rautaray et al., 2003).
Organic fertilizers including farmyard manure, poultry manure and compost may
used for the crop production as a substitute of the chemical fertilizers because
the importance of the organic manures can not be overlooked. Worldwide, there
is growing interest in the use of organic manure due to depletion in the soil
fertility. Economic premiums for certified organic grains have been driving many
transition decisions related to the organic farming (Delate and Camberdella,
2004). Continuous use of fertilizers creates potential polluting effect in the
environment (Oad et al., 2004). Synthesis of chemical fertilizers consumes a
large amount of energy and money. However, an organic farming with or without
chemical fertilizers seems to be possible solution for these situations (Prabu et
al., 2003). The integration of organic sources and synthetic sources of nutrients
not only supply essential nutrients but also have some positive interaction with
chemical fertilizers to increase their efficiency and thereby reduce environmental
hazards (Ahmad et al., 1996).
The use of organic matter is not a complete substitute to chemical fertilizer but
infact, it is an added dimension to organic farming and can play a vital role in
optimizing the best soil use, crop management and conservation. Keeping this
objective in view, the present study was conducted to evaluate the potential of
integrated nutrient management through compost and chemical fertilizer for
improving yield of maize under the Faisalabad conditions.
4
MATERIALS AND METHODS
An experiment was conducted to evaluate the effect of integrated use of
chemical fertilizer (nitrogen) and compost on growth and yield of maize was
conducted at Agronomic Research Area, University of Agriculture, and
Faisalabad. The experiment was laid out in randomized complete block design
(RCBD) with four replications having six treatment i.e. T1(Control),T2 (chemical
fertilizer @ 250-120-125 NPK kg ha-1),T3 (Compost alone @10 t ha-1),T4 ( 25%
Nitrogen from compost + 75% Nitrogen from chemical fertilizer),T 5 (50% Nitrogen
from compost + 50% Nitrogen from chemical fertilizer)andT6 (75% Nitrogen from
compost + 25% Nitrogen from chemical fertilizer ).The crop was sown on a well
prepared seed bed on 18 August, 2008 in 75cm apart rows with the help of a
hand dibbler. Plant to plant distance of 20 cm was maintained at the time of
sowing and later on through thinning the crop at 3 to 4 leaf stage. Recommended
seed rate of 30 kg ha-1 was used. The maize hybrid DEKALB 5219 was sown.
Soil samples were collected with hand auger and analyzed. Nitrogen,
phosphorus and potassium were applied @ 250, 120 and 125 kg ha-1
respectively. The prepared compost was obtained from Lahore Compost (Pvt.)
Ltd. and analyzed chemically for its nutrients. The required amounts of compost
per treatment were collected on these bases as shown in table I.
TABLE I: COMPOSITION OF COMPOST USED
Nutrient
Composition (%)
Nitrogen
2.5
Phosphorus
1
Potassium
1
Organic matter
50
5
Compost was applied at soil preparation and incorporated into the soil. Nitrogen
was applied in two doses i.e. half at sowing and remaining half was top dressed
with 2nd irrigation. All phosphorus and potassium were applied at the time of
sowing. All other agronomic practices except those under study were kept normal
and uniform for all the treatments. The soil fertility was determined from the
sample taken before sowing the crop. The soil chemical analysis was performed
in the Soil Chemical Laboratories of Ayub Agriculture Research Institute,
Faisalabad and a test report obtained was presented in this table II.
Table II: Chemical Analysis of Air Dried Soil
Determination
Unit
pH
Value obtained
7.9
Organic matter
%
0.65
Available P
Ppm
7.3
Available K
Total N
197
Ppm
0.08
The observations plant height at maturity ,number of grain rows per cob, number
of grains per row, number of grains per cob,1000- grains weight ,biological yield
,Grain yield ,grain pith ratio and harvest index were recorded. The collected data
was analyzed statistically by using Fisher’s analysis of variance technique and
individual treatment means were separated by using least significant difference
(LSD) test at 5 percent probability level (Steel et al., 1997).
6
RESULT AND DISCUSSION
Plant height at maturity (cm)
Plant height reflects not only the vegetative behaviour of crop plants in response
to applied inputs but also the productive efficiency of those plants in terms of
grain yield. It plays an important role in formation of photosynthates, by
transporting raw material required for photosynthesis from roots to the aerial
parts of the plant, that are prepared by green parts of the plant in the presence of
sun light and then these photosynthates are partitioned into straw and grain yield
of the plant.The figure no.1 showed that plant height at maturity was the lowest
(154.7 cm) in control treatment where no fertilizer or compost was added. It was
statistically at par with T3 (160.6 cm) where compost alone (10 t ha-1) was
applied. Maximum plant height (197.5 cm) was recorded in T 2 where
recommended dose of chemical fertilizer (250-120-125 NPK kg ha-1) was added.
It was followed by T4 where 191.6 cm plant height was recorded by adding 25%
Nitrogen from compost and 75% Nitrogen from chemical fertilizer; T 5 where plant
height was 184.7 cm as the result of 50% Nitrogen from compost + 50% Nitrogen
from chemical fertilizer application and T 6 where 173.9 cm plant height was
observed by supplying 75% Nitrogen from compost and 25% Nitrogen from
chemical fertilizer.Maximum plant height achieved in T 2 where recommended
dose of chemical fertilizer was applied might be due to quick availability of
nitrogen to plants which enhanced their growth. Minimum plant height in control
treatment (T1) where no compost and fertilizer was added attributed due to less
nutrient availability. These results are in agreement with the findings of Matheus
(2004).
7
Fig 1: Effect of integrated nutrient management on plant
height at maturity
250
197.50
Plant height (cm)
200
191.55
184.73
173.90
160.58
154.70
150
100
50
0
T1
T2
T3
T4
T5
T6
Treatments
Number of grain rows per cob
The number of grain rows per cob is a key factor for determining the yield
performance of maize crop. The data pertaining to number of grain rows per cob
as affected by compost and chemical fertilizer is given in figure no.2. Number of
grain rows per cob was significantly affected by different levels of compost and
chemical fertilizer.The comparison of treatment means shows that generally the
compost and chemical fertilizer applications either alone or in different
combination produced higher number of grain rows per cob than that of control.
Maximum number of grain rows per cob (17.55) was recorded in treatment T5
where 50% nitrogen from compost + 50% nitrogen from chemical fertilizer were
applied. The next higher value (16.60) was obtained in treatment T 4 where 25%
8
Fig 2: Effect of integrated nutrient management on number
of grain rows per cob.
20
17.55
Number of grain rows per cob
18
16.50
15.50
16
15.15
14.40
14
12.10
12
10
8
6
4
2
0
T1
T2
T3
T4
T5
T6
Treatments
nitrogen from compost + 75% nitrogen from chemical fertilizer was applied. It was
followed by the treatment T2 (15.50) in which only recommended dose of
chemical was applied. It was statistically at par with treatment T 6 (15.15) where
75% nitrogen from compost and 25% nitrogen from compost was supplied and
this treatment is similar to T3 (14.40) where compost alone (10 t ha-1) was
used.The minimum number of grain rows per cob (12.10) was recorded in case
of control treatment T1 in which no compost or chemical fertilizer was applied.The
increased number of grain rows per cob in treatment T 5 where 50% nitrogen from
compost + 50% nitrogen from chemical fertilizer was applied might be attributed
due to better plant development through efficient utilization of nitrogen by the
plant due to combined effect of compost and chemical fertilizer. These results are
similar to those reported by Jayaprakash et al., (2003) who revealed that number
9
of grain rows per cob was significantly affected by the use of organic and
inorganic fertilizers in combination.
Number of grains per row
Number of grains per row is considered an important parameter that directly
contributes toward the yield of maize crop. It is mainly defined by the genetic
make up of the plants but also altered by the growing conditions like availability
of nutrients, soil, climate etc, to some extent. The figure no.3 regarding the
number of grains per row showed that number of grains per row is significantly
affected by integrated nutrient management.The comparison of treatment means
shows that compost and chemical fertilizer applications either alone or in different
combination produced higher number of grains per row than that of
control.Maximum number of grains per row (34.70) was found in treatment T 4
where 25% nitrogen from compost + 75% nitrogen from chemical fertilizer were
applied. It was statistically at par with T5 (33.15) where 50% nitrogen from
compost + 50% nitrogen from chemical fertilizer were applied. It was followed by
the treatments T2 (31.55), T6 (30.30) and T3 (28.50). Minimum number of grains
per row was recorded in case of control treatment where on compost and
chemical fertilizer was applied.Maximum number of grains per row in treatment
T4 where 25% nitrogen from compost + 75% nitrogen from chemical fertilizer
were applied might be due to proper and timely nutrient availability which
resulted in better growth. Compost enhanced the chemical fertilizer efficiency.
While in case of control treatment T1 the minimum number of grains per row was
due to reduced growth because nutrient availability was poor. These results are
same as were reported by Jayaprakash et al., (2003).
10
Fig 3: Effect of integrated nutrient management on number
of grains per row.
40
34.70
Number of grains per row
35
31.55
30.30
28.50
30
25
33.15
22.80
20
15
10
5
0
T1
T2
T3
T4
T5
T6
Treatments
Number of grains per cob
This is considered main parameter that contributes directly to the yield of maize
crop. The more the number of grains per cob, the more will be the yield. The data
regarding to number of grains per cob is given in figure no. 4. The analysis of
variance shows that compost and chemical fertilizer had significant affect on the
number of grains per cob.The comparison of treatment means shows that
generally the compost and chemical fertilizer applications either alone or in
different combination produced higher number of grains per cob than that of
control. Maximum number of grains per cob (536.3) was recorded in treatment T 5
where 50% nitrogen from compost + 50% nitrogen from chemical fertilizer were
applied. This increase in number of grains per cob might be due to availability of
nitrogen at proper time, which is required for better growth and development of
plants and increase improvement in moisture retention and soil structure by
11
compost.It is statistically at par with treatment T 4 where 25% nitrogen from
compost + 75% nitrogen from chemical fertilizer were applied in which 531.3
numbers of grains per cob were noted. It was followed by the treatments T 2
where 476.0 number of grains per cob were recorded as the result of
recommended dose of chemical fertilizer (250-120-125 NPK kg ha-1) and T6 in
which 426.3 number of grains per cob were found by adding 75% nitrogen from
compost and 25% nitrogen from chemical fertilizer.Minimum number of grains
per cob (354.8) was recorded in case of control treatment where no organic or
inorganic fertilizers were used. It was statistically at
Fig 4: Effect of integrated nutrient management on number
of grains per cob.
600
531.25 536.25
476
Number of grains per cob
500
426.25
400
386.75
354.75
300
200
100
0
T1
T2
T3
T4
T5
T6
Treatments
par with treatment T3 (386.8) where compost (10 t ha-1) was used. The minimum
number of grains per cob might be a cause of insufficiency of nutrients. Similar
12
findings were given by Iqbal (1997), Chaudhry et al., (1998) and Kumar et
al.,(2002).
1000-grain weight (g)
Among various parameters contributing to the economic yield of a crop, 1000grain weight is of prime importance. It directly relates with the yield of the crop.
Any variation in 1000-grain weight will affect the grain yield. The figure no. 5
shows that integrated nutrient management had affected the 1000-grain weight in
a high significant way.
Fig 5: Effect of integrated nutrient management on 1000grain weight (g).
400
1000 grain weight (g)
350.9
296.2
284.5
300
250
353.6
337.1
350
227.4
200
150
100
50
0
T1
T2
T3
T4
T5
T6
Treatments
The data reveals that maximum 1000-grain weight (353.6 g) was recorded in
treatment 25% nitrogen from compost + 75% nitrogen from chemical fertilizer (T4)
which was statistically at par with treatment T 5 where 350.9 g 1000-grain weight
was found by adding 50% nitrogen from compost + 50% nitrogen from chemical
13
fertilizer. It might be due to the proper dose of chemical fertilizer in combination
with compost and this organic material increased the efficiency of chemical
fertilizer which resulted in better growth, grain size was improved and ultimately
1000-grain weight was increased. These are followed by the treatments T2
(337.2 g) where recommended dose of chemical fertilizer (250-120-125 NPK kg
ha-1) was applied; T6 (296.2 g) 75% nitrogen from compost + 25% nitrogen from
chemical fertilizer and T3 (284.5 g) where compost (10 t ha-1) was applied.The
minimum 1000-grain weight (227.5 g) was recorded in case of control treatment
(T1) in which no compost or chemical fertilizer was added. The decrease in 1000grain weight might be attributed to deficiency of nutrients throughout the plant life
especially at the time of flowering and seed setting. Similar results were reported
by Toor (1990), Sharif et al. (2004) and Mahmoud (2006). They found that
combined application of organic and inorganic fertilizers significantly affect 1000grain weight.
Biological Yield (t ha-1)
Biological yield reflects about the total biomass obtained by the plants during his
life cycle under the prevailing conditions (using different treatments) and it
comprises of three components like stalk, pith yield and grain yield. The figure
no.6 indicated that integrated nutrient management significantly affected the
biological weight of the maize plant at harvest. The significantly highest biological
yield (16.86 t ha-1) was achieved with 50% nitrogen from compost + 50% nitrogen
from chemical fertilizer (T5). Statistically non-significant difference was recorded
in treatments T4 (16.34 t ha-1) and T2 (16.18 t ha-1) where 25% nitrogen from
compost + 75% nitrogen from chemical fertilizer and recommended dose of
chemical fertilizer (250-120-125 NPK kg ha-1) were applied respectively. These
are followed by the treatments T6 (15.46 t ha-1) where 75% nitrogen from
compost + 25% nitrogen from chemical fertilizer was applied and T 3 (14.40 t ha-1)
in which compost (10 t ha-1) was applied. The minimum dry matter (9.748 t ha-1)
was gained in case of control treatment (T1) where no organic and inorganic
fertilizer was applied.
14
The highest biological yield recorded in the treatment (T 5) might be attributed to
more nutrients availability during the life cycle of plants for its proper growth and
development which resulted in healthy plants and ultimately higher biological
yield. The lowest biological yield founded in control treatment may be due to
suppressed growth and development of plants as the result of nutrient deficiency.
These results are confirmatory to Adeniyan and Ojeniyi (2003) and Arshad et al.,
(2004).They discovered that biological yield increase with the combined use of
organic and inorganic fertilizers.
Fig.6: Effect of integrated nutrient management on biological
yield (t ha-1).
18
16.3
16.2
Biological yield (t/ha)
16
16.9
15.5
14.4
14
12
10
9.7
8
6
4
2
0
T1
T2
T3
T4
T5
T6
Treatments
Grain yield (t ha-1)
Grain yield also known as economic yield is the most important plant parameter,
which is the end product of a grain crop. It is influenced by a combination of
internal (genetic) as well as (environmental) factors. It is a function of an
15
interaction among various yield determining components namely the number of
cobs per plants, cob length, number of grains per cob and 1000-grains weight
which showed variations by prevailing growing conditions and various crop
management practices. The data regarding grain yield as influenced by organic
and inorganic fertilizers is given in figure no.7 which showed that integrated
nutrient management had a highly significant effect on grain yield.
Fig.7: Effect of integrated nutrient management on grain
yield (t ha-1).
8
7.2
7
6.6
5.87
6
Grain yield (t/ha)
6.9
5.4
5
4
3.4
3
2
1
0
T1
T2
T3
T4
T5
T6
Treatments
The maximum grain yield (7.182 t ha-1) was recorded in the treatment T4 where
25% nitrogen from compost + 75% nitrogen from chemical fertilizer was applied.
The better grain yield was attributed to greater cob length and 1000-grain weight
and increase in moisture retention and microbial activity by compost. It was
followed by the treatments T5 (6.923 t ha-1), T2 (6.595 t ha-1), T6 (5.872 t ha-1) and
T3 (5.370 t ha-1).The minimum grain yield (3.352 t ha-1) was recorded in control
16
treatment (T1) where no compost and chemical fertilizer was applied. Reduction
in yield might be due to the nutritional imbalance and deficiency of certain
important plant growth elements at various important growth stages like that of
flowering, seed formation and seed maturity. These results are similar to the
findings of Nagassa et al., (2005), Laddha et al.,( 2006), and Ahmad et al.,
(2007).
Grain pith ratio
The data pertaining to grain pith ratio given in figure no.8 showed that all
treatments affected grain pith ratio significantly except control treatment. The
maximum grain pith ratio (4.467) was recorded in the treatment T5 where 50%
nitrogen from compost + 50% nitrogen from chemical fertilizer was applied.
Statistically non-significant difference was observed in the treatments T 4 (3.622)
in which 25% nitrogen from compost + 75% nitrogen from chemical fertilizer was
added and T2 (3.455) where recommended dose of chemical fertilizer (250-120125 kg ha-1) was applied. The treatments T6 (3.115) and T3 (3.033) were also
statistically similar. The minimum grain pith ratio (1.955) was recorded in case of
control treatment where no nutrients were supplied through organic and inorganic
fertilizers.The maximum grain pith ratio (4.467) in the treatment T 5 might be
attributed to the combined effect of compost and chemical fertilizer in proper ratio
which enhanced reproductive growth as the result of high nutrient uptake while
the minimum grain pith ratio (1.955) in case of control treatment T 1 was due to
nutrient deficiency which suppressed vegetative and reproductive growth. These
results are similar to the findings of Nagassa et al., (2005).
17
Fig 8: Effect of integrated nutrient management on grain
pith ratio.
5
4.47
5
4
4
Grain pith ratio
3.62
3.46
3.12
3.03
3
3
2
1.96
2
1
1
0
T1
T2
T3
T4
T5
T6
Treatments
Harvest index (%)
The harvest index is a measure of productive efficiency that how efficiently a crop
can use its physiological inheritance. This determines the amount of
photosynthates being transformed to the economic part of the plant. It is the ratio
of economical yield over biological yield and is expressed in percentage (%). The
higher the harvest index the greater will be the productive efficiency of crop and
vice versa.
18
Fig 9: Effect of integrated nutrient management on harvest
index (%).
50
45.5
45
40.6
40
Harvest index
35
44.0
37.8
36.6
31.6
30
25
20
15
10
5
0
T1
T2
T3
T4
T5
T6
Treatments
The data regarding harvest is given in giure no.9 shows that all the treatments of
compost and chemical fertilizer either alone or in different combinations
significantly affected the harvest index.The maximum harvest index (45.51 %)
was recorded in treatment T4 where 25% nitrogen from compost + 75% nitrogen
from chemical fertilizer was applied. It might be due to the timely availability of
nutrients and increase in water holding capacity by compost.It was statistically at
par with treatment T5 (43.97 %) in which 50% nitrogen from compost + 50%
nitrogen from chemical fertilizer was applied. The minimum harvest index (31.63
%) was recorded in case of control treatment where no compost and chemical
fertilizer was applied. These results are confirmatory to Adeniyan and Ojeniyi
(2003).
19
CONCLUSION
On the basis of these results, it was concluded that plant height, number of grain
rows per cob, number of grains per row, number of grains per cob and 1000-grain
weight were significantly affected by all the treatments.Grain yield, biological yield,
harvest index and grain-pith ratio significantly affected by compost and chemical
fertilizer alone or in different combination. The highest grain yield of 7.18t ha -1 was
obtained with the application of 25% Nitrogen from compost + 75% Nitrogen from
chemical fertilizer.
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