Chia is an emerging cash crop in Kenya and its production is inhibited by lack of agronomic management information. A field experiment was conducted in February-June and May-August 2021, to determine the influence of nitrogen and spacing on growth and yield of Chia. A randomized complete block design with a split plot arrangement was used with four nitrogen rates as the main plots (0, 40, 80, 120 kg N ha-1) and three spacing (30 cm x 15 cm (s1), 30 cm x 30 cm (s2), 50 cm x 50 cm (s3)). Application of 120 kg N ha-1 significantly increased (p≤0.05) vegetative growth and seed yield of Chia. Stem height, branches, stem diameter and leaves increased by 23-28%, 11-13%, 43-55% and 59-88% respectively. Spacing s3 significantly increased (p≤0.05) vegetative growth. An increase of 27-74%, 36-45% and 73-107% was recorded in number of leaves, stem diameter and dry weight, respectively. Chia yield per plant was significantly higher (p≤0.05) in s3. However, when expressed per unit area, s1 significantly produced higher yields. The study recommends 120 kg N ha-1 or higher nitrogen rates and a closer spacing of 15 cm x 30 cm as the best option for Chia production in Kenya.
2. Influence of Nitrogen and Spacing on Growth and Yield of Chia (Salvia hispanica) in Meru County, Kenya
Int. J. Agric. Edu. Ext. 443
protein. In southwestern Germany nitrogen fertilizer is
recommended at 20-40 kg ha-1
to maximize on the yield
and quality of chia. Under 20 kg N ha-1
, Chia produced a
lower yield of 841 kg ha-1
when compared to 40 kg ha-1
which produced a higher yield of 847 kg ha-1
(Grimes et
al., 2019).
In Kenya most Chia farmers utilize broadcasting planting
method, which results in densely populated plants. With
closely populated plants, farmers find it difficult to perform
other management practices such as weeding, which
subsequently results to lower yields. Although a few
Kenyan organizations are advocating for closer spacing
arrangement of 0.3 m x 0.3 m, information on growth and
yields to justify the spacing has not been provided.
However, several studies in other countries have justified
a closer spacing to increase the yields of Salvia hispanica.
In Ghana, Yeboah et al. (2014), established higher yields
ranging from 2790-3208 kg N ha-1
in a closer spacing of
0.5 m x 0.5 m. The same was confirmed by Grimmes et al.
(2019) in southwestern Germany when a narrow row
spacing of 35 cm was used and resulted to higher seed
yields of 1171 kg ha-1
. But these reports were contrary to
the findings of Mary et al. (2018) who found a higher yield
of 579.59 kg ha-1
in a wider spacing of 60 cm x 45 cm in
the Indian environment. Different spacings are
recommended with regard to the environments that Chia
is grown (Win et al., 2018).
In a survey conducted in Nyeri county, Kenya, Gitau et al.
(2019) reported that 77.5 % of the respondents were
willing to venture into Chia production. However, with
limited information on the agronomic management,
production of Chia will be inhibited. This study seeks to
develop a suitable crop management system in terms of
Nitrogen supply and plant spacing in Meru County, Kenya.
The objectives of the study include; (i) to determine the
influence of nitrogen on growth and yields of Chia, (ii) To
determine the influence plant spacing arrangement on
growth and yield of Chia.
MATERIALS AND METHODS
Experimental Materials and Procedures
The experiment was conducted in two seasons, February-
June 2021 and May-August 2021 at Meru University of
Science and Technology, on latitude. 0°08′16′N, longitude.
37°42′33′E, 1420 m above sea level. The experiment was
laid out in a randomized complete block split-plot design
replicated three times with the main plots having four
fertilizer rates (0, 40, 80, 120 kg N ha-1
) and plant spacing
(15 cm x 30 cm, 30 cm x 30 cm, 50 cm x 50 cm) as the
sub-plots. Each sub-plot had a width of 2 m and a width of
3 m. Black and white spotted Chia (Salvia hispanica) was
first sown manually on 26th
February 2021 and 5th
May
2021 on a nursery bed then transplanted to the main plot
after twenty-one days. Calcium
Cultural Practices
Fertilizer application
Ammonium Nitrate (CAN) fertilizer was used to supply
nitrogen and two equal splits were used to top-dress at 7
and 14 days after transplanting (DAT). Fertilizer was
applied in drills of about 4 cm adjacent to the plant rows
and covered with light soil. After fertilizer application,
plants were irrigated to field capacity.
Irrigation
During the dry periods plants were irrigated manually to
field capacity after every three days.
Weed Control
Weeds were controlled twice in each season using a hoe;
this was at 14 and 42 DAT thereafter, crop canopy closed
and weed growth was minimized
Harvesting
Harvesting was conducted when Chia leaves turned
yellow and eventually dried in the field. Chia spikes were
then picked from the plant and threshed manually.
Winnowing was done using trays to separate chaff from
the seeds. Clean seeds were weighed immediately to
determine the yield per plant.
Data Collection
Data collection begun 7 days after transplanting, and was
done at weekly interval until the eighth week. Five plants
were selected at random and labelled in each plot for
recording observations on growth and yield. The growth
and yield variables viz., height, stem diameter, number of
leaves and number of branches, dry mass and yield per
plant were collected using standard procedures. Yield per
plant was converted to yield per unit area through the
multiplication of possible plant population per hectare. The
plant population per unit area was 222222, 111111, and
40000 in plant spacing 15 cm x 30 cm, 30 cm x 30 cm, 50
cm x 50 cm, respectively.
Statistical Analysis
Data collected was analyzed using general linear model
(glm) procedure of Statistical Agricultural software (SAS
2005) and least significance difference (LSD) was
employed to show the mean difference between
treatments. LSD test was used to separate means that
were different at 5% levels of significance. Graphs and
tables were attained using Systat 14 software and excel
package.
3. Influence of Nitrogen and Spacing on Growth and Yield of Chia (Salvia hispanica) in Meru County, Kenya
Njoka et al. 444
RESULTS
Plant height
A
Weeks after transplanting
1 2 3 4 5 6 7 8 9
Height
(cm)
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
0 N
40 N
80 N
120 N
B
Weeks after transplanting
1 2 3 4 5 6 7 8 9
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
0 N
40 N
80 N
120 N
C
Weeks after transplanting
1 2 3 4 5 6 7 8 9
Height
(cm)
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
15cm X 30cm
30cm X 30cm
50cm X 50cm
D
Weeks after transplanting
1 2 3 4 5 6 7 8 9
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
15cm x 30cm
30cm x 15cm
50cm x 50cm
Figure 1. Height of Chia plant as Influenced by nitrogen fertilizer and plant spacing during the February- June 2021 (A
and C), and May-August 2021 (B and D) seasons.
The bars represent LSD values (p≤ 0.05).
There were no significant interactions between nitrogen
and spacing on vegetative growth of Chia. Plants supplied
with 120 kg N ha-1
were significantly taller between 3-8
weeks after transplanting (Fig 1 A, and B). At week 8 when
height measurements were terminated, plants in the 120
kg N ha-1
treatment had heights ranging 100 cm in May-
August and 114 cm in February-June season, while control
plants (0 kg N ha-1
) had significantly lower heights ranging
81 cm in May-August and 89 cm in February-June 2021
(Fig 1 A, and B). During the February-June 2021 season,
plants in the 80 kg N ha-1
were significantly taller than
those in the 40 kg N ha-1
(Fig 1 A). However, this difference
was not observed in the May-August season (Fig. 1 B).
In a plant spacing of 30 cm x 15 cm plants were
significantly taller between 3-8 weeks after planting (Fig
1C and D), At week 8 plants in the 30 cm x 15 cm plant
spacing treatment plants had higher heights ranging 102-
114 cm, while plants in a wider spacing of 50 cm x 50 cm
had significantly lower heights ranging 82-92 cm (Fig. 1 C
and D). During the February-June season, plants in the
control (30 cm x 30 cm) plant spacing were significantly
taller from 3-8 week than those in the 50 cm x 50 cm plant
spacing (Fig 1C). However, this difference was not
recorded in the May-August 2021 season (Fig. 1d). Plant
height measurements in the nitrogen and spacing
treatments had a steady increase from week 3-6 thereafter
a constant height was recorded (Fig 1).
Number of leaves
Plants supplied with 120 kg N ha-1
maintained a significant
high number of leaves from 3-8 weeks after transplanting
(Fig 2 A, and B). At week 8, plants supplied with 120 kg N
ha-1 had significantly higher number of leaves followed by
80 kg N ha-1, 40 kg N ha-1
, while control plants had the
lowest number of leaves. A higher number of leaves
ranging between 312-434 was recorded in plants supplied
with 120 kg N ha-1, while a lower number of leaves ranging
between 196-230 was recorded in control plants (Fig 2 A,
and B).
4. Influence of Nitrogen and Spacing on Growth and Yield of Chia (Salvia hispanica) in Meru County, Kenya
Int. J. Agric. Edu. Ext. 445
A
Weeks after transplanting
1 2 3 4 5 6 7 8 9
Number
of
leaves
0
50
100
150
200
250
300
350
400
450
500
0 N
40 N
80 N
120 N
B
Weeks after transplanting
1 2 3 4 5 6 7 8 9
0
50
100
150
200
250
300
350
400
450
500
0 N
40 N
80 N
120 N
C
Weeks after transplanting
1 2 3 4 5 6 7 8 9
Number
of
leaves
0
50
100
150
200
250
300
350
400
450
500
15cm X 30cm
30cm X 30cm
50cm X 50cm
D
Weeks after transplanting
1 2 3 4 5 6 7 8 9
0
50
100
150
200
250
300
350
400
450
500
15cm X 30cm
30cm X 30cm
50cm X 50cm
Figure 2. Number of leaves of Chia as influenced by nitrogen supply and spacing during the February-June 2021 (A and
C), and May-August 2021 (B and D) seasons.
The bars represent LSD values (p≤0.05).
A wider spacing of 50 cm x 50 cm produced plants with
significantly greater number of leaves followed by control
while the lowest number of leaves were produced by plants
spaced in 15 cm x 30 cm arrangement between 3-8 weeks
after transplanting (Fig 2 B, and D). In week 8, plants in a
50 cm x 50 cm spacing produced higher leaves ranging
294-429 while in 15 cm x 30 cm plants produced lesser
number of leaves ranging 231-246.
A
Leaves
0 50 100 150 200 250 300 350 400 450 500
Height
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
15 cm x 30cm
30cm x 30cm
50cm x 50cm
0 N
40 N
80 N
120 N
B
Leaves
0 50 100 150 200 250 300 350 400 450 500
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
15cm x 30cm
30cm x 30cm
50cm x 50cm
0 N
40 N
80 N
120 N
y=0.37x
r
2
=0.98
y=0.32x
r
2
=0.99
Figure 3. Height of Chia as functions of the number of leaves as influenced by nitrogen supply and spacing during the
February-June 2021 (A), and May-August 2021 (B) seasons.
5. Influence of Nitrogen and Spacing on Growth and Yield of Chia (Salvia hispanica) in Meru County, Kenya
Njoka et al. 446
The plant height increased as a function of the number of
leaves (Figure 3) (Table 1). The linear functions were
neither influenced by spacing nor nitrogen fertilizer given
that they produced a similar slope.
Table 1. 95 % confidence intervals for plant height as
functions of number of leaves.
Season (2021) Slope (95%CI)
February-June
May-August
0.32 0.30-0.34
0.37 0.33-0.42
Stem Diameter
A
Weeks after transplanting
1 2 3 4 5 6 7 8 9
Stem
Diameter
(mm)
0
2
4
6
8
10
12
14
16
18
0 N
40 N
80 N
120 N
C
Weeks after transplanting
1 2 3 4 5 6 7 8 9
Stem
Diameter
(mm)
0
2
4
6
8
10
12
14
16
18
15cm X 30cm
30cm X 30cm
50cm X 50cm
B
Weeks after transplanting
1 2 3 4 5 6 7 8 9
0
2
4
6
8
10
12
14
16
18
0 N
40 N
80 N
120 N
D
Weeks after transplanting
1 2 3 4 5 6 7 8 9
0
2
4
6
8
10
12
14
16
18
15cm X 30cm
30cm X 30cm
50cm X 50cm
Figure 4. Stem diameter of Chia as influenced by Nitrogen supply and Spacing during the February-June 2021 (A and C),
and May-August 2021 (B and D) seasons.
The bars represent LSD values (p≤0.05).
120 kg N ha-1
treated plants produced significantly thicker
stem diameters from 3-8 weeks after transplanting (Fig 4
A, and B). In the 8th
week of stem diameter measurement,
plants supplied with 120 kg N ha-1
produced stem
diameters ranging between 12.68-14.59 mm while control
plants had significantly thinner diameters ranging 8.14 mm
in the May-August 2021 season and 10.20 mm in the
February-June 2021 season (Fig 4 A, and B). Plants
supplied with 80 kg N ha-1 during the February-June 2021
season had significantly thicker stems than those in the 40
kg N ha-1
(Fig 4 A). However, in the May-August 2021
season the difference was not observed.
In 50 cm x 50cm spacing, plants produced significantly
thicker stems from 3-8 weeks after transplanting (Fig 4 C,
and D). In 50 cm x 50 cm, Chia plants had generally thicker
stem diameters ranging 12.33-14.02 mm, while 15 cm x
30cm plant spacing produced thinner plant stems ranging
8.45-10.08 mm (Fig 4 C, and D). Control plant spacing had
significantly thicker stem as compared to 15 cm x 30 cm
plant, but still lower than 50 cm x 50cm plant spacing in
both seasons. In contrast, thicker stem diameters were
recorded in February-June season ranging from 10.08-
14.02 mm while a thinner diameter was recorded in May-
August 2021 season ranging from 8.45-12.33 mm (Fig 4).
6. Influence of Nitrogen and Spacing on Growth and Yield of Chia (Salvia hispanica) in Meru County, Kenya
Int. J. Agric. Edu. Ext. 447
Number of Branches
Plants supplied with 120 kg N ha-1
had a significant high
number of branches in both seasons as compared to
control plants (Table 2). Under 120 kg N ha-1
plants
reached a maximum of 15.11 branches plant-1
in February-
June 2021 season and 14.78 branches plant-1
in May-
August 2021 season while control plants had a lower
number of branches ranging 13.22-13.30 plant-1
. Although,
Control plants had fewer number of branches there was no
significant differences between 80 and 40 kg N ha-1
(Table
2). Plants subjected to a wider spacing of 50 cm x 50 cm
had a significant increase in the number of branches as
compared to control and 15 cm x 30 cm spacing. More
number of branches ranging 14.50-14.91plant-1
were
recorded from plants with 50 cm x 50cm spacing (Table 2).
In both control and 15 cm x 30 cm plant spacing, no
significant differences were recorded, and plants had
lower number of branches ranging 13.50-13.75 plant-1
(Table 2).
Table 2. Number of branches of Chia as influenced by
nitrogen supply and spacing
Number of branches per plant
February-June
2021
May-August
2021
Fertilizer rates
(N)
Branches Branches
120 15.11a 14.78a
80 14.11ab 13.89b
40 14.00b 13.78b
0 13.30b 13.22b
LSD 1.01 0.67
P 0.0146 0.0021
Spacing (cm) Branches Branches
50 x 50 14.91a 14.50a
30 x 30 13.75b 13.75b
15 x 30 13.75b 13.50b
LSD 0.87 0.6
P 0.0164 0.0078
CV 7.12 5.01
Means followed by the same letters down the column are
not significantly different (p≤0.05)
CV-coefficient variability, LSD- least significance
difference.
Dry Weight
The total dry weight of Chia plant was significantly higher
in plants supplied with 120 kg N ha-1
as compared to plants
in other nitrogen treatments (Table 3). Control plants had
lower total dry wight ranging 57.15-88.32 g plant-1
while
plants supplied with 120 kg N ha-1
had increased total dry
weight ranging 115.25-141.20 g plant-1
. Similarly, the dry
weight of spikes, leaves and stem, leaf and spike were
significantly higher in plants supplied with 120 kg N ha-1
.
120 kg N ha-1
resulted to plants with significantly higher
stem dry weight ranging (47.12-61.55 g plant-1
), leaf dry
weight (14.92-15.07 g plant-1
), spike dry weight (53.21-
64.58 g plant-1
). In both seasons the stem dry weight was
much lower in control plants but significantly similar to
those plants that had a supply of 40 kg N ha-1
.
In a plant spacing of 50 cm x 50 cm, plants had a significant
increase in total dry weight. (Table 3). The total dry weight
of pants subjected to 50 cm x 50 cm spacing ranged
between 110.71-155.68 g plant-1
while plants subjected to
a 15 cm x 30 cm spacing had a significantly lower total dry
weight of 63.78-75.09 g plant-1
. Control plants had
intermediate total dry weight. The stem, leaf and spike dry
weight were significantly higher in a wider spacing of 50
cm x 50cm as compared to a lower dry weight recorded in
a closer spacing of 15 cm x 30 cm. (Table 3). A plant
spacing of 50 cm x 50 cm resulted to higher stem dry
weight ranging (42.05-70.05 g plant-1
), dry leaf weight
(16.03-18.34 g plant-1
) and dry spike weight (52.64-67.29
g plant-1
). During February-June 2021, control plants had
a significantly higher spike dry matter than those in a 15
cm x 30 cm plant spacing. However, the difference was not
observed in the May-August 2021 season (Table 3).
Yields
There was no significant interaction between nitrogen
supply and plant spacing on yield of Chia plant. Nitrogen
application of 120 kg N ha-1
significantly increased the
seed yield per plant (Table 4). Plants supplied with 120 kg
N ha-1
resulted to yields ranging between 37.82-43.76 g
plant-1
, while control plants had significantly lower yields
ranging 17.96-29.21 g plant-1
. Similarly, plants supplied
with 120 kg N ha-1
resulted to significantly higher yields in
tonnes ha-1
. In 120 kg N ha-1
plants produced significant
higher yields ranging 3.82-4.35 tonnes ha-1
as compared
to control plants that had a yield ranging 1.83-3.02 tonnes
ha-1
. For both 80 kg N ha-1
and 40 kg N ha-1
there were no
significant differences in yields tonnes ha-1
for both
seasons. During the May-August 2021 season, plants in
40 kg N ha-1
had significant higher yields per plant than the
control plants. However, the difference was not observed
in the February-June 2021 season. Plant spacing had an
influence on the yield per plant and yield per unit area. A
wider spacing of 50 cm x 50 cm produced significantly
higher yields per plant followed by control plants, while
plants arranged in a 15 cm x 30 cm had the lowest yield
per plant. A higher yield ranging between 39.69-51.47 g
plant-1
was obtained in 50 cm x 50 cm plant spacing, while
a significant low yield ranging 16.26-20.59 g plant-1
was
obtained in a closer spacing of 15 cm x 30 cm. Contrary to
the yields per plant, the equivalent yields per unit area
were significantly higher in a plant spacing of 15 cm x 30
cm, while a low yield was obtained in a 50 cm x 50 cm plant
spacing. Control plants with a plant spacing of 30 cm x 30
cm had intermediate yield per unit area. Yields ranging
3.61-4.57 tonnes ha-1
, 2.94-3.85 tonnes ha-1
and 1.59-2.05
tonnes ha-1
were recorded in 15 cm x 30 cm, control and
50 cm x 50 cm plant spacing, respectively (Table 4).
7. Influence of Nitrogen and Spacing on Growth and Yield of Chia (Salvia hispanica) in Meru County, Kenya
Njoka et al. 448
Table 3. Dry weight of Chia as influenced by nitrogen supply and spacing.
Dry weight per plant
February-June 2021 May-August 2021
Fertilizer
rates (N)
Stem (g)
leaf
(g)
spike (g)
Total dry
weight
(g)
Stem (g)
Leaf
(g)
spike (g)
Total dry
weight (g)
120 61.55a 15.07a 64.58a 141.20a 47.12a 14.92a 53.21a 115.25a
80 53.15b 14.07a 52.93b 120.15b 38.62b 12.71ab 39.51b 90.83b
40 46.56c 12.07b 44.98c 103.61c 29.96c 10.35bc 33.72bc 74.03c
0 41.57c 7.54c 39.21c 88.32d 24.01c 6.61c 26.53c 57.15d
LSD 6.17 1.91 6.89 7.85 6.87 4.54 9.53 14.52
P 0.0001 0.0001 0.0001 0.0001 0.0001 0.0039 0.0002 0.0001
Spacing (cm) Stem (g)
Leaf
(g)
Spike
(g)
Total dry
weight
(g)
Stem (g)
Leaf
(g)
Spike
(g)
Total dry
weight (g)
50x50 70.05a 18.34a 67.29a 155.68a 42.05a 16.03a 52.64a 110.71a
30x30 48.79b 11.72b 50.02b 110.53b 34.35b 11.26b 34.19b 79.80b
15x30 33.28c 7.84c 33.97c 75.09c 29.05b 6.84c 27.89b 63.78c
LSD 5.35 1.66 5.97 6.80 5.95 3.94 8.26 12.58
P 0.0001 0.0001 0.0001 0.0001 0.001 0.0014 0.0001 0.0001
CV 12.18 15.7 13.67 6.94 19.7 39.89 24.94 17.19
Means followed by the same letters down the column are not significantly different (p≤0.05)
CV-coefficient variability, LSD- least significance difference.
Table 4. Chia seed yield as influenced by nitrogen supply and spacing.
Yields
February-June 2021 May-August 2021
Fertilizer rates (N) g/plant *tonnes/ha g/plant *tonnes/ha
120 43.76a 4.35a 37.82a 3.82a
80 36.26b 3.36b 30.05b 2.66b
40 33.02bc 3.25b 24.05bc 2.55b
0 29.21c 3.02b 17.96c 1.83c
LSD 5.31 0.81 6.21 0.69
P 0.0002 0.0149 0.0001 0.0002
Spacing (cm) g/plant *tonnes/ha g/plant *tonnes/ha
50x50 51.47a 2.05c 39.69a 1.59c
30x30 34.63b 3.85b 26.46b 2.94b
15x30 20.59c 4.57a 16.26c 3.61a
LSD 4.6 0.7 5.38 0.6
P 0.0001 0.0001 0.0001 0.0001
CV 14.95 23.16 22.62 22.62
Means followed by the same letters down the column are not significantly different (p≤0.05)
CV-coefficient variability, LSD- least significance difference.
* -yields of g/plant converted to tonnes/ha
DISCUSSION
In both seasons nitrogen supply and plant spacing
independently influenced Chia growth and yield as
indicated by the lack of significant interactions. Plant
height and number of leaves of Chia increased by 23-28
% and 59-89 %, respectively in plants supplied with 120 kg
N ha-1
than in plants that were not supplied with nitrogen.
This increase could be attributed by the role of nitrogen on
the vegetative growth of the plant. Increase in nitrogen
increases nitrogen in the cell sap in form of proteins, amino
acids and amides thus leading to cell multiplication and
elongation which eventually lead to taller plants and higher
number leaves as compared to plants that had no nitrogen
fertilizer (Rasha et al., 2020). The constant number of
leaves recorded from week 7 was as a result of defoliation
of the basal leaves and formation of new leaves on the
upper part of the plant.
On the other hand, a narrow spacing of 15 cm x 30 cm,
increased the height by 23 -24% more than the wider
spacing of 50 cm x 50 cm. The taller plants recorded in
15cm x 30 cm were due to competition of plants for light
thus increase in apical dominance and suppression of the
8. Influence of Nitrogen and Spacing on Growth and Yield of Chia (Salvia hispanica) in Meru County, Kenya
Int. J. Agric. Edu. Ext. 449
lateral shoots. Although a wider spacing produced shorter
plants, the number of leaves increased by 74 % and 27 %
in the February-June, and May-August 2021 seasons,
respectively. At a wider spacing, plants received optimum
light, space, moisture and nutrients thus decreased
competition between plants. These results are in
agreement with the results of Mohanty et al. (2021) who
reported, 60% increase in height after application of 100
kg N ha-1
and a narrow spacing of 50 cm x 20 cm. The
study also revealed 110 % increase in the number of
leaves in a wider spacing of 60 cm x 20 cm and 100 kg N
ha-1
. Despite the height of Chia in this study falling below
that of Mohanty et al. (2021), the plant heights recorded in
this study were still under the normal chia plant height of
between 70-250 cm (Souza and Chavez, 2017). With an
increase in height and leaves being recorded in higher
nitrogen rates, the linear relationship between the height
and number of leaves was not influenced by nitrogen
fertilization neither the spacing levels.
Supply of 120 kg N ha-1
increased the stem diameter of
Chia by 43% and 55 % in the February-June, and May-
August 2021 seasons, respectively. The increase was
linked to the role of Nitrogen in plant cell division and cell
expansion. The sharp increase in stem diameter observed
from the third week after transplanting could be related to
the vegetative stage of the plant hence some of the photo-
assimilates being produced by the leaves was deposited
on the stem. The constant stem diameter readings were
as result of the plants reaching their maturation stage thus
no more growth and development of the plant. Although,
the results indicate that February-June season had thicker
stems as compared to May-August 2021 season the stem
diameter ranged in the recommended range of 5-30 mm
(Rossi et al., 2020). These results confer with those
findings of Chan et al. (2020), where 120 kg N ha-1
produced thick stem diameters of 8.66 mm and a thinner
stem diameter of 7.22 mm.
At a wider spacing of 50 cm x 50 cm, plants had an
increased stem diameter of 35 % and 46 % in the February
-June, and May-August 2021 seasons respectively.
Adequate space allowed plants to receive adequate light,
water and nutrients. In addition, plant produced more
leaves which formed a robust canopy, early before the
flowering stage hence providing the plant with adequate
light for photosynthesis and this led to defining of the stem
(Konuskan and Kilinc, 2019). The reduced stems in 15 cm
x 30 cm were caused by the closer spacing between plants
thus increasing competition for light, water and nutrients.
Thus, the photo-assimilates produced by the plant was
directed more to the elongation of the plant rather than the
expansion. These results agree with Robin and Stephen
(2017) who analyzed Chia under different spacing
arrangements 20 cm x 20 cm and 10 cm x 10 cm and
observed a thicker diameter of 30.4 mm a wider spacing
and thinner diameter of 20.2 mm in a closer spacing.
However, these results differ with those of Win et al. (2018)
and Yeboah et al. (2014) who found no significant
differences in chia stem diameter under different spacing
arrangements.
The number of branches increased by 12 % in 120 kg N
ha-1
as compared to plants that were not supplied with
nitrogen. The high number of branches achieved by the
increased rate of fertilization was as a result of increased
rate of cell division. Nitrogen is also known to activate
vegetative growth of plant thus this could be attributed to
the high number of branches obtained in 120 kg N ha-1
.
Similarly, a wider spacing of 50 cm x 50 cm increased the
number of branches by 7-8%. The increased number of
branches in a wider spacing is as a result of adequate
space, nutrient, light and water thus little or no competition.
Shading as a result of closer spacing between plants
suppressed lateral growth and as a result lead to apical
dominance. Mary et al. (2018) reported a 29 % increase in
the number of branches when Chia was subjected to a
wider spacing of 60 cm x 45 cm. Contrary, Yeboah et al.
(2014) reported a 26 % increase in the number of branches
at a closer spacing of 0.5 m x 0.5 m. The lower number of
branches recorded in this study could be attributed to chia
variety difference.
A Supply of 120 kg N ha-1
to Chia plants led to 66 %, 112
%, 80 % and 76 % increase in dry weight of the stem,
leaves, spikes and total dry weight of the plant,
respectively. Nitrogen is an important component since it
induces the growth of plant via plant protein metabolism,
transportation of the photo assimilates and the production
of proteins and nucleic acids. Also, the low production of
leaves in plants denied nitrogen fertilizer could have
contributed to decreased photosynthesis thus decreased
production of photo assimilates and transportation to the
different parts of the plant. The reduced number of leaves
in plants led to the decreased leaf dry weight. The same
case could have also occurred to the dry mass of the
spikes and dry mass of the stem given the few spikes and
branches obtained in plants with no nitrogen fertilizer.
Increase nitrogen supply accelerated cell division and
expansion thus leading to increased biomass buildup.
Such a response has been reported by Souza and
Chavez, (2017) who found 8.06 g plant-1
after applying 125
kg N ha-1
.
A plant spacing of 50 cm x 50 cm resulted to 80 %, 134 %,
94% and 92 % increase in dry weight of the stem, leaves,
spikes and the total dry weight of the plant. Increased
space between plants led to increased dry mass in all plant
parts. A wider space meant that plants had a luxuriant
growth due to adequate space, nutrient, water and light.
Increased light interception to the leaves meant increased
photosynthesis and subsequently high production of
assimilates as well as increased transportation of photo
assimilates to other parts of the plant. Shading
experienced by plants in a closer spacing meant that there
was decreased photosynthesis thus low photo-assimilates
production and hence low plant dry mass. This is in
agreement with Mohanty et al. (2021), who reported a total
9. Influence of Nitrogen and Spacing on Growth and Yield of Chia (Salvia hispanica) in Meru County, Kenya
Njoka et al. 450
dry weight of 159 g plant-1
after subjecting Chia to 60 cm x
20 cm and 100 kg N ha-1
Nitrogen supply of 120 kg N ha-1
increased the plant seed
yield by 50 %, and 111 % in February-June, and May-
August 2021 seasons, respectively. The equivalent seed
yield per hectarage was also found to have the same
response to nitrogen. This increase can be attributed by
the role of nitrogen in increasing the number of leaves thus
promoting photosynthesis and subsequently higher yields.
A wider spacing of 50 cm x 50 cm resulted to increase in
plant yield by 149 % and 125% in February-June, and
May-August 2021 seasons, respectively. These results are
in agreement with those of Mary et al. (2018) who recorded
higher yield per plant of 11.90 g in a wider spacing of 60cm
x 45cm. However, the increase in yield per plant recorded
in wider spacing did not translate to higher seed yield per
unit area. In a closer spacing of 15 cm x 30 cm, 124 %
increase in seed yield per unit area was recorded. The
higher yields could be as a result of high number of plants
in a closer spacing, given that there were only 40,000, and
222,222 plant stands in 50 cm x 50 cm and 15 cm x 30 cm,
respectively. Win et al. (2018) confirmed these results by
reporting high yields of 1.094 tonnes ha-1
in a plant density
of 192,000 plants (41.66 cm x 25 cm). Similarly, Mohanty
et al. (2021), recorded a seed yield of 1.210 tonnes ha-1
in
treatment combination of 50 cm x 20 cm and 100 kg N ha-
1
.
CONCLUSION
Applying 120 kg N ha-1
significantly increased vegetative
growth of Chia in terms of plant height, number of leaves,
dry matter, number of branches and stem diameter.
Similarly, supplying 120 kg N ha-1
significantly increased
the seed yield of Chia. Based on the significant differences
in growth and yield between plants supplied with 120 kg N
ha-1
and 80 kg N ha-1
it is possible that applying high rates
of nitrogen application could result to more growth and
yield. On the other hand, using a wider spacing of 50 cm x
50 cm, Chia vegetative growth increased significantly but
resulted to shorter plants. Chia seed yield per plant
increased significantly in 50 cm x 50 cm plant spacing. On
the contrary, this resulted to significant reduction in yield
per unit area. Given that high yield can be achieved in a
closer spacing the study recommends the adoption of 15
cm x 30 cm plant spacing and a nitrogen fertilizer of 120
kg ha-1
, although a risk of increased seed shuttering and
lodging need to be considered.
REFERENCES
Bilalis, D., Tabaxi, I., Zervas, G., Tsiplakou, E., Travlos, I.
S., Kakabouki, I., & Tsioros, S. (2016). Chia (Salvia
hispanica) fodder yield and quality as affected by
sowing rates and organic fertilization. Communications
in Soil Science and Plant Analysis, 47(15), 1764-1770.
Chan, G. A. H., Fidelis, R. R., de Oliveira Tavar, T. C.,
Lopes, M. B. S., Marques, K. R., & Rauber, W. A.
(2020). Nitrogen fertilization of medicinal plants of the
species Salvia hispanica L.(chia) in Gurupi, Tocantins,
Brazil. Revista Cubana de Plantas Medicinales, 25(1),
1-14.
Felemban, L. F., Attar, A. M. A., & Zeid, I. M. A. (2021).
Medicinal and Nutraceutical Benefits of Chia Seed
(Salvia hispanica). Journal of Pharmaceutical
Research International, 32(41), 15-26.
Gitau, D. M., Mburu, M. W., & Kiarie, D. M. (2019). The
Economic, Health and Nutritional benefits of Chia
(Salvia hispanica L.) Farming In Nyeri County, Kenya–
Baseline survey analysis. IOSR Journal of Agriculture
and Veterinary Science, 12(4), 2319-2380
Grimes, S. J., Phillips, T. D., Capezzone, F., & Graeff-
Hönninger, S. (2019). Impact of row spacing, sowing
density and nitrogen fertilization on yield and quality
traits of chia (Salvia hispanica L.) cultivated in
Southwestern Germany. Agronomy, 9(3), 136.
Konuskan, O., & Kilinc, C. (2019). Effect of plant density
on growth and grain yield of some hybrid corn (Zea
mays L.) varieties under mediterranean environment.
Fresenius Enviromental Bulletin, 28(4), 2795-2801.
Kwena, K., Karuku, G. N., Ayuke, F. O., & Esilaba, A. O.
(2019). Nitrogen Deficiency in Semi-Arid Kenya: Can
Pigeonpea fix it?. East African Agricultural and Forestry
Journal, 83(4), 322-340.
Mary, J., Veeranna, H. K., Girijesh, G. K., Sreedhar, R. V.,
Dhananjaya, B. C., & Gangaprasad, S. (2018). Effect of
spacing and fertilizer levels on yield parameters, yield,
and quality of Chia (Salvia hispanica L.). International
journal of pure and applied bioscience, 6, 259-263.
Mohanty, P., Umesha, C., Sarangi, D. R., &
Kumarsanodiya, L. (2021). Impact of Spacing and
Nitrogen Levels on growth and Yield of Chia (Sylvia
hispanica L.). Biological Forum – An International
Journal, 13(1), 148-153.
Mucheru-Muna, M., Mugendi, D., Pypers, P., Mugwe, J.,
Kung'u, J., Vanlauwe, B., & Merckx, R. (2014).
Enhancing maize productivity and profitability using
organic inputs and mineral fertilizer in central Kenya
small-hold farms. Experimental Agriculture, 50(2), 250-
269.
Muñoz, L. A., Cobos, A., Diaz, O., & Aguilera, J. M. (2013).
Chia seed (Salvia hispanica): an ancient grain and a
new functional food. Food reviews international, 29(4),
394-408.
Njeri, V., Mburu, M. W., & Koskei, K. (2019). Mould
Characterization and Mycotoxin Quantification of Chia
Seeds (Salvia hispanica L.) Grown in Kenya. Journal of
food Research, 8(2), 119-128.
Rasha, S., El-Sheshtawy, A. A., & Ali, H. E. (2020).
Phenology, architecture, yield, and fatty acid content of
Chia in response to sowing date and plant spacing.
Fayoum Journal of Agricultural Research and
Development, 34 (1), 314-331.