American-Eurasian J. Agric. & Environ. Sci., 10 (4): 544-550, 2011
© IDOSI Publications, 2011
Corresponding Author: Peiman Zandi, Department of Agronomy, Faculty of Agriculture, Islamic Azad University,
Takestan Branch, Iran, Tel: +98-9375836734, Fax: +98-1327562193, E-mail: firstname.lastname@example.org.
Agronomic Study of Fenugreek Grown under Different In-Row Spacing and
Nitrogen Levels in a Paddy Field of Iran
Peiman Zandi, Amir Hossein Shirani Rad and Leila Bazrkar-Khatibani
Department of Agronomy, Faculty of Agriculture,
Islamic Azad University, Takestan Branch, Iran
Department of Agronomy and Plant Breeding,
Mazandaran University, Sari, Iran
Abstract: The objective of this study was to evaluate the effects of different levels of nitrogen and plant
density on yield and yield components of Fenugreek. This study was conducted at Guilan region (Iran) in a
Paddy field during 2008-2009 cropping season. The experiment was carried out using split plots based on
randomized complete block design with 4 replications. Four levels of nitrogen (0, 25, 50 and 75 kg N haG) as
the main factor and four levels of plant density (60, 80, 100 and 120 plants mG) as sub-plots were investigated.
Result indicated that nitrogen fertilizer effect was significant on number of pods per branch, number of pods
per plant, seed yield and biological yield. Plant density significantly a ffected biological yield (p<0.05).
The highest seed yield (1468 kg haG) was produced by using 75 kg N haG. There was positive and significant
correlation between seed yield and biological yield. According to mean comparisons of simple effects,
the highest biological yield belonged to 75 kg N haG and 120 plants mG, respectively.
Key words: Trigonella foenum-graecum L. % Nitrogen fertilizer % Plant density % Yield
Manohar  found that in a winter crop of fenugreek on
loamy sand soils, seed and forage yields were higher with
Fenugreek (Trigonella foenum-graecum L) is an
annual, self pollinating, legume crop, believed to be native
to the Mediterranean region but now, is widely cultivated
in India and other parts of the World . Fenugreek seed
is used in foods as a spice, in artificial flavoring of maple
syrup, as a condiment and, in the production of steroid
and other hormones for the pharmaceutical industry .
Fenugreek is a dryland crop but responds well to minimum
application of irrigation [1, 3], can be a very useful legume
crop for incorporation into short-term rotation .
Using nitrogen in fenugreek leads to growth
increase, deferred maturation, producing good leaves,
developed stem and the plants’ luxuriant dark-green color
which indicates a desired growth. Also, plant density on
the row and within the rows affects the yield and is
controlled by the seed rate .
Results from fenugreek cultivation after harvesting
rice in Mazandaran province (North of Iran) showed that
upon using nitrogen fertilizer in the form of 100kg haG
urea, the highest yield was obtained . Rathore and
20 kg NhaG and 50 kg P haG. Thapa and Maity 
reported that applying 50 kg N haG could be effective in
increasing the yield. Billaud and Adrian  suggested
using 60 kg N haG and 40kg K O haG for fenugreek
cultivation. Duke  recommended fenugreek plants be
spaced in rows 45 cm apart, 8cm for in-row spacing and
22.5kg seed haG rate to be broadcast, while Yadav et al.
 suggested 30cm spacing, within the rows for sowing.
Also, Chaudhary  suggested fenugreek to be sown
using 25kg seed haG.
Optimal use of rice paddies and double
cropping after harvesting rice is of great significance
here and winter cultivation of fenugreek, when rice
growers especially in the northern provinces of Iran are
free from agricultural activities could be an appropriate
The aim of this research was to investigate the effect
of various rates of nitrogen fertilizer as well as effect of
planting density on yield and yield components of
fenugreek in Paddy fields.
Am-Euras. J. Agric. & Environ. Sci., 10 (4): 544-550, 2011
MATERIALS AND METHODS
The bundles were manually threshed to record seed yield
(kg haG). Seeds were additionally dried until 10% of
This study was conducted under rainfed condition
after rice harvest in one of the rice paddies at Guilan
province (North of Iran) in 1 of November during 2009-
2010 cropping season. The site is located at latitude of
37°16 N, longitude of 49°26 E and 11 meters above the
sea level, in temperate climate. The soil type was loamy
with pH 4.46 and EC 1.05 ds/m.
In this experiment, nitrogen fertilizer (Urea) as the
main factor including four rates of pure nitrogen (N =0,
N = 25, N =50 and N =75 kg haG) and plant density as the
minor factor at four levels (D =60, D =80, D =100 and
D =120 plants mG) were studied as a split plots based on
randomized complete block design (RCBD) with four
replications. Each experimental plot comprised 8 lines of
4 m long, with a line spacing of 30 cm.
After tillage, disk, land leveling and implementing the
plan on the experimental field, the seeds that were soaked
24 hours prior to sowing, were broadcasted two times at
the given density in continuous rows with the distance of
30 cm between rows. Then, with the same density, they
were thinned in two stages. Nitrogen fertilizer was used in
two splits. The first application (1/3 of the total rate) was
made as the starter fertilizer at the time of sowing and the
second application (2/3 of the total rate) was made as
topdressing, one month after sowing and before the
formation of nodules on the roots. Based on soil test
results, 100 kg haG of triple super phosphate were
distributed as a basal dressing for all treatments. With
consideration of precipitations in Guilan province, which
supply the water requirement of double cropping
products, water requirement was also met through rainfall.
Hand hoeing was carried out during the growth period.
Any symptom of pests and diseases did not observe
during the study.
Almost 10 days before maturity, ten random samples
were selected from each experimental unit and their yield-
related traits (i.e. number of pods per stem, number of
pods per branches, number of pods per plant, pod length
and number of seeds per pod) were measured. At full
maturation stage, in order to estimate seed yield,
biological yield and 1000-seed weight, a final harvesting
from a 2.5m area in the middle of each plot was done in
June, 2010. The crop was harvested manually in each plot
separately and tied into bundles. The bundles were left in
the field for drying until constant weight. The sun-dried
bundles were weighed by scale to determine total biomass
plotG (at the given area) and converted into kg haG.
moisture and subsequently yield was determined.
Four samples of 100 seeds were taken from
each seed lot of the experimental units and then
weighed. Their average multiplied by 10 (x~ ×10)
recorded 1000 seed weight (g). Economic yield
divided by biological yield multiplied with 100 gave
harvest index in percent. Productivity index (PI) was
determined from the following relationship given by
PI= (Reproductive organs weight/ biological yield) ×100
The data so collected were analyzed statistically with
MSTATC software, by using Fisher’s analysis of variance
technique. Duncan’s Multiple Range Test (DMRT) was
applied to compare means of each trait at 5% probability.
Correlation coefficients were computed using “SPSS ver.
18.0” for Windows 7 following the methods of Steel and
Torrie . The clustering was based on the squared
Euclidean distance. And to build dendrogram using
Ward's hierarchical clustering method which involves an
agglomerative clustering algorithm.
RESULTS AND DISCUSSION
The results in Table 1 revealed that, pod length and
number of pods per stem were not significantly affected
by difference among applied densities, nitrogen levels and
interaction thereof. Since number of seeds per pod is
usually more controlled by the plant genotype than by
natural factor which is due to the number of ovules being
constant, it could be concluded that pod length is
influenced by genetic factors and is less affected by
The effect of nitrogen fertilizer on number of
pods per branches, showed a highly significant
difference (P<0.01) (Table 1). Application of 25kg N haG
with 26.32 pods per branches had the highest number
of pods, which was statistically at par with 50 and
75 kg NhaG.
The lowest number of pods per branches (18.23) was
recorded for the nitrogen application of 0 kg N haG;
therefore, in the Duncan grouping method it was placed
in a separate statistical group (Table 2). The effect of plant
density and the interaction effect of nitrogen × plant
density were not significantly effective in this trait
Am-Euras. J. Agric. & Environ. Sci., 10 (4): 544-550, 2011
Table1: Analysis of variance of fenugreek for pod length(PL), number of pods stemG(NPS), number of pods branchesG(NPB), number of pods plantG(NPP),
number of seeds PodG(NSP), 1000 seed weight(SW), seed yield (SY), biological yield(BY), harvest index(HI) and productivity index(PI) under
different nitrogen levels and planting densities.
PLNPSNPB NPP NSPSW
variationdf SYBY HIPI
ns ns ns ns ns ns* ** ns ns
ns ns** ** ns ns** ns ns
ns ns ns ns ns ns ns** ns ns
ns ns ns ns ns ns ns ns ns ns
c.v%5.5312.55 23.6615.336.945.69 12.5 10.12 12.5711.27
*, ** = Significant at 5 and 1% probability levels, respectively, by the F test. ns = Non-significant.
(N: Nitrogen rates; D: Plant densities; N×D: Interaction effect of Nitrogen rates× Plant densities; MS: Mean Square)
Table 2: Effect of nitrogen levels & plant densities on pod length(PL), number of pods stemG(NPS), number of pods branchesG(NPB), number of pods
plantG(NPP), number of seeds podG(NSP), 1000 seed weight(SW), seed yield(SY), biological yield(BY), harvest Index(HI) and productivity Index
(PI) of Fenugreek in Estimated means .
PL (cm) NPS NPB NPP NSP
Nitrogen (kg haG )
Density (plants mG )
Means not sharing a common letter in a column differ significantly at 0.05 level of probability, using Duncan’s Multiple Range Test.
SW(g)SY(Kg haG )
BY(Kg haG )
HI (%)PI (%)
In this experiment, number of pods per plant was
significantly affected by nitrogen fertilizer (p<0.01),
whereas plant density and interactions between plant
density and nitrogen showed not-significant effects
(Table 1).Means comparison of nitrogen rates using
Duncan test at the probability level of 5% showed that
25kg N haG produced the highest number of pods per
plant (45.39) and based on the Duncan grouping method
it was placed in the first group which was statistically at
par with the 50kg N haGAlso,the control treatment(N )
had the least number of pods per plant (35.17) (Table 2).
Generally, this trait is one of the most important
components of yield and in cases of affecting any factor,
seed yield will be directly affected. It is also quite effective
in increasing the number of seeds per plant relative to the
number of seeds per pod. By increasing the duration of
the vegetative growth and dry matter accumulation,
nitrogen fertilizer caused more flowers to be formed in
branches through the crop growth rate (CGR) and finally
led to more pods in branches. Apparently, assimilate
materials produced by the plant during the maturity period
(since Anthesis till physiological maturity) compared with
those produced in the main stem caused more flowers in
branches and eventually more pods to be produced. In
the research conducted by Bismillah Khan et al. , it
was concluded that density did not have any significant
effect on the number of pods per plant. Also, Khadem
Hamzeh et al.  reported that as the density increased,
the number of pods per single plant decreased; however,
it increased per unit area.
The results in Table 1 indicated that, number of
seeds per pod and 1000-seed weight were not
significantly affected by different planting density,
nitrogen levels and interaction thereof. In their experiment,
Ghanbari and Taheri-Mazandarani  concluded that
environmental factor were less effective in changing the
number of seeds per pod and that it was more influenced
Am-Euras. J. Agric. & Environ. Sci., 10 (4): 544-550, 2011
Moreover, 1000-seed weight is considered as one of
the genetic characteristics of a cultivar which is less
affected by environmental factors such as light, moisture
and temperature .
Fenugreek seed yield was affected significantly
(P<0.05) by Nitrogen rates (Table 1).Maximum seed yield
(1468kg haG )was obtained from 75 kg N haG,which was
statistically at par with 50kg N haG (1464kg haG ).
Nitrogen application at the rate of 0 kg N haG produced
the lowest seed yield (1301kg haG), but statistically at par
with 25kg N haG (1332kg haG) (Table 2).Both 75 kg N
haG and 50kg N haG were statistically superior to other
two nitrogen levels. It may be due to the reason that
nitrogen fertilizer aids in seed development in legumes.
Verma et al.  along with Detoroja et al.  found that
using organic and inorganic fertilizers such as
nitrogenous and phosphorus ones were effective in
increasing fenugreek yield. Differences among densities
and interaction between densities and nitrogen levels did
not affect significantly (p<0.05) seed yield of Fenugreek
(Table 1). Usually, plant density is one of the most
effective agronomic factors for determining the yield
which is in itself affected by cultivar and climatic
conditions. Bothe et al.  reported that plant density
did not have any significant effect on the plant's yield,
while Glamo?lija et al. , Singh et al.  and Gowda et
al.  obtained contradictory results. The differences in
results might be due to differences in environmental
conditions under which these experiments were
Furthermore, Nitrogen application had a significant
effect on the biological yield (P<0.05) while the interaction
effect for nitrogen rate × plant density on the biological
yield was not significant (Table 1). Mean comparisons of
nitrogen rates using Duncan’s test (p<0.05) indicated that
the highest biological yield (6336kg haG ) was obtained
using 75kg NhaG which was at par with N (50kg N haG).
On the other hand, the lowest biological yield (5567kg
haG) was that of the control treatment (N ) and was in
turn at par with 25 and 50kg NhaG; thus, it was placed in
the same statistical group as those (Table 2).Effect of
N(nitrogen) on yield attributes of Fenugreek has been
observed earlier [25,26]. According to the results in
Table 1, a highly significant (P<0.01) effect of plant
density on biological yield at the full maturity stage was
observed in this study (Table 1). The highest biological
yield (6227kg haG) was obtained from 120 plants mG.In
relation to biological yield, application of 80 plants mG2
(5853 kg haG) 100 plants mG (6111kg haG) and
120 plants’m were statistically at par with each other.
Also, the lowest biological yield (5402kg haG) was
obtained Using 60 plant’s mG (D ), so it was put in a
separate statistical group (Table 2). With regards to the
effect of different nitrogen rates and plant density on the
agronomic traits and also the development of shoots,
Toghraei et al.  showed that, increased vegetative
growth and developed shoots, were followed by
increased biological yield as a result of more nitrogen
application. Also, Forawi and Elsheikh  in their study
found that N-fertilization significantly increased the dry
matter production and plant nitrogen content.
Since the highest biological yield was obtained upon
using 75kg NhaG, it seemed that application of higher
dosage of nitrogen fertilizer as a nutritional condition was
accompanied by the increase of the total dry matter
(TDM) in this treatment. Our results indicated that as the
density increased from 60 up to120 plant’s mG, the
biological yield increased as well. Hence, it could be said
that as the plant density increased, competition for
growth requirement factors [which includes adequate
space for growth and development of shoots and roots
(planting geometry), sufficient light, nutrients and water
requirements] increased and as a result, single plants
showed less growth and development. Therefore, due to
increase number of plants per unit area despite the
reduced growth and development of each plant (reduced
total dry weight of a single plant), the biological yield per
square meters increased.
As regards harvest index (Table 1), Effect of N
(nitrogen), D (plant density) and the interaction effect of
N×D was not significant.
Usually, harvest index is a sustainable parameter for
a cultivar and its substantial differences result from the
environmental conditions during a plant's growth period
. Higher seed yields are normally obtained from plants
with more dry weights. But in general, the increase of the
said yield is more a result of increased harvest index than
the biomass increase . In the present study; we found
that, due to the growth increase of the plant's superior
organs (Shoots), the growth of vegetative organs and
reproductive ones were proportional with specified rate,
what meant that seed production of fenugreek was a
function of vegetative growth.
Finally, based on obtained results in Table 1,
Productivity index did not significantly affected by all
studied treatments and their interactions. In fact, a ratio of
the biological yield which forms the weight of
reproductive organs is called productivity index. In other
words; Productivity index (PI), indicates the level of
photosynthesis materials allocated to reproductive
organs. The actual “PI” is calculated by the ratio of pod
weight to the maximum plant weight during its growth
Am-Euras. J. Agric. & Environ. Sci., 10 (4): 544-550, 2011
Table 3: Phenotypic correlation coefficients among 10 fenugreek characters grown under rain fed condition.
1: Pod length
2: Pod stemG
3: Pod branchesG
4: Pod plantG
5: Seed podG
6: 1000seed weight
7: Seed yield
8: Biological yield
9: Harvest index
110: Productivity index -.070
1 ns ****
1 ns nsns ns
nsns ns ns ns
nsns nsns ns ns
ns ns* nsnsns**
nsnsns ns ns ns nsns
nsns nsns ns nsns**
*, ** = Significant at 5 and 1% probability, respectively. ns= Non-significant
Fig. 1: Dendrogram of 16 Treatment Combination of Iranian fenugreek using WARD’s method based on agronomic traits
measured under rain fed conditions. The cluster diagram revealed two major lineage groups at linkage distance
20. Lineage ‘A’ at linkage distance 15 was further divided into two clusters (I and II). Among the lineage ‘A’,
cluster I consists of 5 accessions including four treatment combinations (N D , ND , ND N D and N D ).
Cluster II consists of seven accessions; N D , N D N D N D N D N D and N D , while lineage group
‘B’comprises of only one cluster (III). Cluster III comprises four treatment combinations; N D , N D , N D
and N D .
4 3, 4 2
2 2, 2 3, 2 4, 3 2 41
In terms of this trait, it could be said that the growth
of vegetative and reproductive organs had a certain ratio,
i.e. the level of the allocation of assimilate materials to
reproductive and vegetative physiological sinks was to a
measured traits. However, there was a positive significant
correlation between: (1) Number of pods per stem and the
number of pods per plant (r=0.682**), (2) Number of pods
per branches with the number of pods per plant
(r=0.972**) and the biological yield (r=0.506*), (3) Harvest
index and Productivity index (r=0.619*) and also (4)
Correlations: In order to study and compare correlated
relationships between the evaluated traits at different
nitrogen levels and plant densities, all correlation
coefficients were evaluated (Table 3).
Pod lengths, number of seeds per pod and 1000-seed
weight were not significantly correlated with other
between seed yield and biological yield (r=0.638**).
With consideration of the fact that the biological
yield made the greatest contribution to the increase of
seed yield and showed a positive significant correlation
with the number of pods per branches, it could be
concluded that reproductive organs indirectly resulted in
Am-Euras. J. Agric. & Environ. Sci., 10 (4): 544-550, 2011
the increase of seed yield.On the other hand, whatever,
may be chosen for increasing seed yield, the improvement
could be achieved only through biological yield. Hence it
may be concluded that biological yield is the main trait
which is responsible for manipulation of seed yield in
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Cluster Analysis: The results of the cluster
analysis (Ward’s method) based on agronomic
characteristics are presented in the Figure 1, the cluster
diagram revealed two major groups. Groups A and B.
Group A comprised of two clusters one containing 5
accessions and the other containing 7 accessions and
group B consist of one cluster of only four accessions
N D N D N D ,N D
1 2,2 1,113 1.
This dendrogram shows that the accessions
in one cluster are mostly identical and have less
In conclusion, we suggest that, simultaneous
Application of pure nitrogen at the rate of 75kg NhaG and
a density of 120 plants mG (i.e. N D ) for achieving high
seed and biologic yield in paddy fields is possible. Since
the said treatment combination was quite related to N D ,
N D , N D and N D in the cluster analysis, applying
N D , due to its less fertilizer and seed consumption
would be ideal.
Application of nitrogen fertilizer can significantly
improve both seed and biological yield under rain fed
condition in temperate climates.
However, further confirmation of the trends seen in
this experiment needs to be obtained before more specific
recommendations can be made.
The author wishes to thank the Islamic Azad
University, Takestan Branch, Iran for giving all types of
support in publishing this study.
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