American Journal of Plant Sciences, 2011, 2, 297-302
doi:10.4236/ajps.2011.23033 Published Online September 2011 (http://www.SciRP.org/journal/ajps)
297
Effect of Nutrient Management and Planting
Geometry on Productivity of Hybrid Rice
(Oryza sativa L.) Cultivars
Ranjita Bezbaruha, Ravi Chandra Sharma, Pabitra Banik*
Agricultural and Ecological Research Unit, Indian Statistical Institute, Kolkata, India.
Received December 29th, 2010; revised May 13th, 2011; accepted July 14th, 2011.
ABSTRACT
Field experiments were conducted during the wet seasons of 2006 and 2007 at the Agricultural Experimental Farm of
the Indian Statistical Institute, Giridih, a part of eastern plateau region of India. The study was designed to investigate
the effect of planting geometry and nutrient management practices on productivity of two hybrid rice cultivars.
Split-plot design with three replications was adopted to carry out the experiment by allocating combinations of treat-
ments of planting geometry and rice cultivar in main-plots and nutrient management treatments in sub-plots.
“CNRH-3” rice proved its efficiency in terms of grain yield that was also reflected in yield attributing characters such
as number of productive tillers, number of grains per panicle, length of panicle, panicle weight, test weight and harvest
index. Higher rice grain yield was reg istered when th e cultivars gro wn in 20 cm × 20 cm planting geometry. Rice culti-
vars grown with the application of ino rganic fertilizers alone produced maximum grain yield and also recorded higher
values of ancillary characters. The maximum amount of N, P and K was taken up by the “CNRH-3” rice, whereas
maximum residual soil fertility was recorded in “Pro Agro 6201” rice. Maximum N, P and K uptake values were re-
corded in 20 cm × 20 cm crop geometry and inorganic fertilizers treatment.
Keywords: Hybrid Rice Cultivars, Planting Geometry, Vermicompost, Nutrient Uptake, Soil Fertility
1. Introduction
One of every three peoples depends on rice for more than
half of their daily food and one in nine (approximately 700
million) depends on rainfed rice. Ninety percent of the
world’s rice is grown and consumed in Asia. Rice is also
an important staple food in some countries of Latin Amer-
ica and Africa. Asian rice production has increased by
24% during 1965 t o 1980 and that was at t ribut ed to the use
of higher rate of fertilizers, mainly N-fertilizer. Rice pro-
ductivity is now at stagnant situation or declining in areas
where N-fertilizer application is very high; it has also rai-
sed the concerns about sustainability of monoculture rice
[1]. Food security in India (1.6 billion by 2050 that will
require 450 Mt of food grain production) is a challenge [2].
To achieve food security, hybrid rice can be one of the
most feasible options to increase 15% to 20% of food pro-
duction [3,4]. The hybrid cultivars are more responsive to
higher doses of nutrients [5,6] and thereby the yield poten-
tiality is all high.
It is a big concern that whether the agronomic prac-
tices, especially planting geometry for hybrid rice are same
as for conventional rice. Thus, there is a need to optimize
the planting geometry for hybrid rice [7]. Proper planting
geometry have m ore advantages such as, to maximize light
utilization efficiency, improves aeration within crop can-
opy, enhances soil respiration and provides better weed
control thereby higher crop yields [8] .
Of late, there has been serious concern about long-
term adverse effect of continuous and indiscriminate use
of inorganic fertilizers on soil health, biodiversity and
environment [9]. The organic matter in sub-tropics soils
is low because of high temperature and intense microbial
activity. Soil organic matter is the key attribute of soil
quality [10] therefore organic matter has to be replen-
ished to maintain the soil health. Apart from nutritional
effects [11], application of organic manure influences
plant physiologically. It also provides growth regulating
substances to plants and modifies soil physical behaviour
[12]. Vermicompost is a good source of organic manure
that can be used as an alternative to chemical fertilizers
in rice cultivation [1 3]. Organic matter dynamics is simi-
lar in different cropping systems but its significance for

Effect of Nutrient Management and Planting Geometry on Productivity of Hybrid Rice (Oryza sativa L.) Cultivars
298
specific soil properties or crop productivity varies con-
siderably with soil type [14,15]. With the above back
drop the experiments have been undertaken to measure
the effect of crop geometry and the usefulness of organic
materials on yiel d of low la nd hybri d rice and soil fertili ty.
2. Materials and Methods
2.1. Study Site
A study was carried out at the Agricultural Experimental
Farm of the Indian Statistical Institute, Giridih (at 24˚1'N,
86˚3'E and altitude 920'), India during the wet seasons of
2006 and 2007. The average annual rainfall of the study
area is 1343 mm but the distribution is highly seasonal
(about 86% of total rainfall occurs in between June to
September). The average maximum and minimum tem-
peratures are 23.8˚C and 12.6˚C respectively. Average
annual potential evapotranspiration is 1293 mm with the
relative humidity ranges from 78% to 95%. The so il was
moderately well drained lateritic sandy loam (30.0%
coarse sand, 26.8% fine sand, 25.0% silt and 18.2% clay).
Soil was slightly acidic in reaction (6.4) with low in or-
ganic carbo n (0.52%), available N (132 kg N ha –1) and P
(12 kg P ha–1) but medium in K (156 kg K ha–1).
2.2. Experimental Setup
The experiment was laid out in split-plot design an d rep-
licated thrice. Combinations of rice cultiv ars (V1: CNRH
3 and V2: Pro Agro-6201) and crop geometry (G1: 15
cm × 15 cm, G2: 20 cm × 20 cm and G3: 25 cm × 25 cm)
were allocated in the main-plots and nutrient manage-
ment practices such as F0: absolute control, F1: recom-
mended dose (RD, 140:60:60 kg N, P2O5, K2O ha–1)
through inorganic sources, F2: RD of N through vermi-
compost, F3: 50% RD of NPK through inorganic +50%
RD of N through vermicompost and F4: 75% RD of NPK
through inorganic +25% through vermicompost were
assigned in sub-plots. The recommended dose of NPK
was applied in the form of urea (46-0-0), single super
phosphate (0-16-0) and muriate of potash (0-0-60). Ver-
micompost (1.25-0.8-0.65) was incorporated in soil as
per the treatment at the time of final ploughing. Rice cu l-
tivars were transplanted on 15th July and 18th July and
were harvested on 9th December and 11th December in
2006 and 2007, respectively. Agronomic management
practices and plant protection measures were followed as
per the recommendation.
2.3. Soil Sampling and Analysis
Soil samples were collected from each plot at the depth
of 0 - 20 cm just after harvest of rice in both the years.
These soil samples were sieved (2 mm) and analyzed for
available N by alkaline potassium permanganate method
[16] and organic carbon by wet oxidation method [17].
Mineralizable P and exchangeable K were estimated by
Olsen’s method [18] and neutral normal ammonium ace-
tate method [19], respectively. Concentrations of N, P
and K in rice grain and str aw wer e esti mated by using th e
standard methods as advocated by Jackson [19].
2.4. Statistical Analysis
The data obtained during the study were subjected to
statistical analysis using the IRRISTAT (software devel-
oped by International Rice Research Inst itute, Phili ppines).
3. Results
3.1. Plant Height
Plant height of rice cultiv ars was significantly influenced
by the crop geometry and nutrient management practices
(Table 1). Plant height of “CNRH 3” rice was higher
(88.66 cm) over the Pro Agro 6201 (85.88 cm). Rice
grown at 15 cm × 15 cm apart recorded higher plant
height (88.42 cm) whereas 25 cm × 25 cm spacing re-
corded shortest ones (86.16 cm). Rice grown with 100%
RD of NPK supplied through inorganic sources (F1)
produced tallest plants but it was statistically at par with
that of the F4 treatment.
3.2. Productive Tillers
“CNRH 3” rice produced maximum numbers of repro-
ductive tillers (349 m–2) (Table 1). Rice grown at 20 cm
× 20 cm spacing, irrespective of cultivars and fertilizer
treatments, produced highest reproductive tillers per unit
area (395 m–2) and which was followed by 25 cm × 25
cm treatment. Among the nutrient management practices,
F1 treatment was reco rd ed 46% hi gh er rep ro du c tive tillers
over the F0 treatment.
3.3. Filled Grains per Panicle
“CNRH 3” rice produced 31% higher filled grains per
panicle over Pro Agro 6201 (Table 1). Rice transplanted
in 20 cm × 20 cm spacing produced maximum number of
filled grains per panicle (73.13) followed by rice when
grown at 25 cm × 25 cm spacing (64.38). Rice had 85%
and 63% higher grains per panicle when grown with F1
and F4 treatments respectively over the F0.
3.4. Panicle Length and Weight
Both panicle leng th (21.65 cm) and weight (2 .55 g) were
recorded maximum in “CNRH 3” rice (Table 1). Irre-
spective of cultivars, both the values were higher when
rice was grown at 20 cm × 20 cm apart followed by at 25
cm × 25 cm spacing. Fertilizer treatment F1 had 65%
higher panicle length over the control (F0).

Effect of Nutrient Management and Planting Geometry on Productivity of Hybrid Rice (Oryza sativa L.) Cultivars
299
3.5. Test Weight
Rice cultivar CNRH 3 (26.24 g) recorded higher test
weight (weight of 1000 grains) over the other one (Table
1). Significantly highest test weight (26.50 g) of rice was
registered when grown in 20 cm × 20 cm crop spacing
whereas least test weight was in 15 cm × 15 cm. Test
weight was significantly affected by the nutrient man-
agement practices. Fertilizer treatment F1 followed by F4
recorded the higher test weight over the others.
3.6. Grain Yield
The “CNRH 3” rice produced the highest grain yield
(4527 kg·ha–1) and harvest index (HI; 0.47) over Pro
Agro-6201 (Table 2). Maximum grain yield was re-
corded when rice cultivars were transplanted in 20 cm ×
20 cm crop spacing (4804 kg·ha–1) followed by 25 cm ×
25 cm spacing. HI also recorded the similar trend. There
was a significant variation in grain yield and HI due to
nutrient management practices as well and were regis-
tered highest when the cultivars grown with the F1.
Whereas least values of grain yield and HI were recorded
in the F0.
3.7. Nutrient Uptake
Among the rice cultivars, higher N, P and K uptakes
were recorded by CNRH3 (Table 3). Cultivars grown at
20 cm × 20 cm spacing accumulated higher nutrients
while least amount of nutrients uptake was at 15 cm × 15
cm. Rice cultivars recorded maximum nutrients (NPK)
uptake when they received 100% nutrients through inor-
ganic fertilizers (F2) but it was statistically at par with the
treatment F4. However, least amount of nutrients uptake
was found when rice grown w i t hout any fert ilizers (F0).
3.8. Residual Soil Nutrients
Residual soil nutrients (N, P and K) values were maxi-
mum in “Pro Agro 6201” rice (Table 4). Crop geometry
did not have significant effect on soil fertility. Although
the values were maximum in 15 cm × 15 cm crop spac-
ing. The VC treatment (F2) had maximum residual soil
nutrients (NPK) values whereas these were least in F0
followe d by F1 treatments.
Table 1. Effect of crop geometry and nutrient management practices on plant growth and yield attributes of hybrid rice c ul-
tivars (pooled data of 2006 and 2007).
Treatment Plant height
(cm) Productive Tillers m–2 Filled grains panicle–1 Panicle length (cm) Panicle weight (g) Test weight (g)
Cultivars
V1: CNRH3 88.66 348.99 74.42 21.65 2.55 26.24
V2: Pro Agro 6201 85.88 334.31 56.58 20.42 2.14 25.66
SEm± 0.95 5.39 7.28 0.22 0.08 0.16
LSD (p = 0.05) 2.11 12.00 16.23 0.49 0.18 0.35
Crop geometry
G1: 15 cm × 15 cm 88.42 287.26 59.59 20.85 1.92 25.78
G2: 20 cm × 20 cm 86.16 394.73 73.13 21.50 2.69 26.50
G3: 25 cm × 25 cm 87.05 343.33 64.38 20.80 2.38 25.52
SEm± 0.19 7.03 1.93 0.08 0.09 0.23
LSD (p = 0.05) 0.42 15.66 4.30 0.18 0.20 0.51
Nutrient
F0: Control 80.92 272.09 45.09 15.67 1.90 22.59
F1: RDF (160:60:60) 92.23 398.69 83.49 25.86 2.85 28.07
F2: 100% RDF through VC* 84.79 319.90 59.72 19.98 2.10 24.01
F3: 50% RDF + 50% VC 87.52 342.78 67.52 20.67 2.19 25.12
F4: 75% RDF + 25% VC 90.63 376.96 73.32 23.03 2.56 26.94
SEm± 1.60 16.46 5.14 0.98 0.16 0.42
LSD (p = 0.05) 3.22 33.12 10.34 1.97 0.33 0.85
*Vermicompost.

Effect of Nutrient Management and Planting Geometry on Productivity of Hybrid Rice (Oryza sativa L.) Cultivars
300
Table 2. Grain yield, straw yield and harvesting index as influenced by rice cultivars, crop geometry and nutrient manage-
ment practices.
Grain yield (kg·ha–1) Straw yield (kg·ha–1) Harvesting index
Treatment 2006 2007 2006 2007 2006 2007
Cultivars
V1: CNRH3 4577 4869 5266 5506 0.47 0.47
V2: Pro Agro 6201 4415 4683 5440 5695 0.45 0.45
SEm± 55 50 69 60
LSD (p = 0.05) 123 112 153 134
Crop geometry
G1: 15 cm × 15 cm 4195 4485 5339 5482 0.44 0.45
G2: 20 cm × 20 cm 4804 5091 5446 5741 0.47 0.47
G3: 25 cm × 25 cm 4493 4756 5274 5583 0.46 0.46
SEm± 87 76 35 57
LSD (p = 0.05) 194 169 77 126
Nutrient
F0: Control 3928 4035 5424 5702 0.42 0.42
F1: RDF (160:60:60) 4992 5203 5517 5595 0.48 0.48
F2: 100% RDF through VC* 4298 4637 5127 5314 0.46 0.47
F3: 50% RDF + 50% VC 4485 4849 5308 5579 0.46 0.47
F4: 75% RDF + 25% VC 4773 5158 5382 5831 0.47 0.47
SEm± 66 58 46 57
LSD (p = 0.05) 132 117 93 114
*Vermicompost.
Table 3. Nutrients (NPK) uptake as influenc ed by rice cultivars, crop geometry and nutrient management practices.
Nutrients uptake (kg·ha–1)
Treatment Nitrogen Phosphorus Potassium
Cultivars 2006 2007 2006 2007 2006 2007
V1: CNRH3 86.52 89.66 18.87 21.08 128.95 133.15
V2: Pro Agro 6201 84.81 87.35 17.09 20.28 123.91 129.07
SEm± 0.57 0.44 0.55 0.35 1.85 1.44
LSD (p = 0.05) 1.26 0.98 1.23 0.78 4.12 3.21
Crop geometry
G1: 15 cm × 15 cm 81.97 83.76 14.98 17.41 116.84 121.15
G2: 20 cm × 20 cm 92.48 93.99 20.12 23.63 133.89 139.69
G3: 25 cm × 25 cm 85.21 87.83 18.86 21.03 128.49 132.48
SEm± 1.44 1.21 0.85 0.72 2.03 1.50
LSD (p = 0.05) 3.20 2.70 1.90 1.60 4.53 3.35
Nutrient
F0: Control 70.79 71.23 13.53 15.84 109.53 112.35
F1: RDF (160:60:60) 100.73 104.07 23.59 25.89 151.27 156.24
F2: 100% RDF through VC* 79.38 81.14 15.47 17.91 117.79 120.47
F3: 50% RDF + 50% VC 87. 81 90.02 17.79 2 0 .83 121.69 127.98
F4: 75% RDF + 25% VC 93. 99 96.21 19.53 2 3 .97 131.85 138.54
SEm± 2.75 2.09 1.16 1.08 3.10 2.80
LSD (p = 0.05) 5.54 4.21 2.33 2.17 6.23 5.64
*Vermicompost.

Effect of Nutrient Management and Planting Geometry on Productivity of Hybrid Rice (Oryza sativa L.) Cultivars
301
Table 4. Residual soil nutrients status as influence d by rice cultivars, crop geometry and nutrient management practices.
Residual soil nutrients status (kg·ha–1)
Treatment Nitrogen Phosphorus Potassium
Cultivars 2006 2007 2006 2007 2006 2007
V1: CNRH3 141.08 146.21 12.15 13.53 123.87 129.24
V2: Pro Agro 6201 145.78 149.52 13.38 14.43 125.57 132.08
SEm± 1.14 0.96 0.30 0.23 0.84 0.80
LSD (p = 0.05) 2.54 2.14 0.67 0.52 1.87 1.79
Crop geometry
G1: 15 cm × 15 cm 148.23 152.86 13.91 15.12 128.87 134.28
G2: 20 cm × 20 cm 139.57 143.94 11.87 12.96 121.88 127.95
G3: 25 cm × 25 cm 142.48 146.87 12.51 13.85 123.42 129.74
SEm± 1.06 0.66 0.50 0.44 1.81 1.50
LSD (p = 0.05) 2.36 1.48 1.12 0.98 4.03 3.35
Nutrient
F0: Control 136.98 137.97 10.09 10.94 109.56 111.75
F1: RDF (160:60:60) 141.60 1 4 4.53 11.45 12.97 122.32 127.47
F2: 100% RDF through VC* 151.85 157.92 16.15 19.43 138.28 146.24
F3: 50% RDF + 50% VC 143.79 151.58 12.01 14.12 128.19 136.54
F4: 75% RDF + 25% VC 142.99 147.45 14.17 16.83 125.28 131.29
SEm± 1.55 1.27 0.77 0.63 1.51 1.43
LSD (p = 0.05) 3.12 2.56 1.54 1.27 3.04 2.87
*Vermicompost.
4. Discussion
Biomass production is a function of genetic character of
the crop cultivar and the environmental factors, inputs
applied and their management. Many factors are attrib-
uted to obtain the higher biomass production and among
them, planting geometry plays a vital role in augmenting
rice grain yield [7]. Wider spacing facilitates maximum
light interception, better inter-culture operations and bet-
ter soil aeration [8]. This could be reason for obtaining
the maximum yield in wider row spacing.
Highest grain yield under inorganic sources of nutrients
might be due to immediate release and availability of
nutrients when compared with organic nutrients sources.
Chemical fertilizers release nutrients instantly resulting
higher crop biomass production. On the contrary, organic
sources release nutrients slowly for longer period that
does not meet the crop demand thus reduces crop bio-
mass production. However, combined application of nu-
trients, 75% RD through fertilizer and 25% N through
VC, produced higher biomass due to synchronized and
balanced nutrients supply for a longer period of time
[20,21]. The yield advantage on the application of or-
ganic sources is due to their capab ility to supp ly essential
nutrients other than N, P and K. Application of farm yard
manure is known to increase concentrations of Fe, Mn,
Zn, and Cu in rice. Higher nutrients uptake with the ap-
plication of inorganic fertilizer might be due to higher
nutrient concentration along with higher biomass produc-
tion [22,23]. Application of organic manure along with
chemical fertilizer accelerates the microbial activity [24],
increases nutrients use efficiency [25] and enhances the
availability of the native nutrients to the plants resulting
higher nutrients uptake [26]. Vermicompost applied plots
built-up residual soil fertility because of slow release of
nutrients and reduction of nutrient losses.
5. Conclusions
Rice cultivar, CNRH 3 produced maximum grain and
straw yield. Rice, irrespective of cultivars, grown with
inorganic fertilizers alone produced maximum grain and
straw yield but it was statistically at par with that of ap-
plication of 25% nutrient through organic and 75%
through inorganic sources. Rice transplanted in 20 cm ×
20 cm spacing produced maximum biomass. Pro Agro
6201 rice cultivar, 25 cm × 25 cm crop geometry, and
sole organic manure had built-up maximum soil fertility.
It may be recommend that rice cultivar CNRH 3, plant-
ing geometry 20 cm × 20 cm and INM treatment (25:75

Effect of Nutrient Management and Planting Geometry on Productivity of Hybrid Rice (Oryza sativa L.) Cultivars
302
organic: inorganic) can be adopted to obtain the higher
biomass production while maintaining the soil fertility.
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