A Comprehensive research study on effect on combine application of nitrogen and boron on yield and Growth of sunflower. By Ravi Banjade IAAS TU, Nepal Email : rabibanjade3@gmail.com

2. 1. INTRODUCTION:
Sunflower is an important oilseed crop which ranks third after soybean and groundnut
as a source of edible oil in the world. As in other crops, it requires NPK fertilization.
Nitrogen deficiency is generally the most limiting nutritional disorder affecting
sunflower production. Appropriate fertilization is important for getting high yield per
hectare, and N deficiency is the most limiting nutritional disorder to sunflower
production. Similarly, Adequate soil fertility is one of the requirements for profitable
sunflower production and that N is the most yield limiting nutrient for its production.40-
80 kg N ha-1 (depending on the available water) of fertilizer alone or associated with
green manuring was sufficient. Sufficient N for maximum sunflower yield was
provided by 84 kg N ha-1, while 100 kg N ha-1 was suitable for nitrogen fertilization
of sunflower. However, nitrogen fertilization is very variable and it depends on the
amounts of the element already present in the soil and the potential yield of the
environment. Research information regarding the effect of nitrogen on oil contents and
oil yield of sunflower are scarce. The study was initiated to determine the effects of
different rates of nitrogen on growth, seed and oil yields of sunflower. Of the nutrient
elements required by plants, nitrogen is most essential and is required in the largest
amount from soil. Nitrogen is essential for all life processes in plants. It is a vitally
important plant nutrient and is the most frequently deficient of all nutrients. Nitrogen
is a mobile element and can easily be lost through leaching, erosion, denitrification, etc.
Application of N to crops produces abundant vegetative growth, large leaves with deep
green color and good yield. This has made nitrogen an important constraint to crop
production in the zone. Of the nutrient elements required by plants, nitrogen is most
essential and is required in the largest amount from soil. Nitrogen is essential for all life
processes in plants. It is a vitally important plant nutrient and is the most frequently
deficient of all nutrients. Nitrogen is a mobile element and can easily be lost through
leaching, erosion, denitrification, etc. Application of N to crops produces abundant
vegetative growth, large leaves with deep green color and good yield. Boron is a
micronutrient required for all plant nutrition. The main functions of boron relate to cell
wall strength and development, cell division, fruit and seed development, sugar
transport, and hormone development. Some functions of boron interrelate with those of
nitrogen, phosphorus, potassium and calcium in plants. The recommend dose of boron
is 15 kg/ha. Balanced nutrition is essential for optimum crop growth.
2. BACKGROUND:

3. Sunflowers are native to North America, and were first cultivated by Native Americans
over 4,500 years ago. The early Americans also discovered that sunflower oil could be
extracted and used for cooking. In the 16th century, Spanish explorers brought
sunflowers back to Europe, where they quickly became popular. Sunflowers were
initially grown as ornamental flowers, but their value as a crop was soon recognized.
By the 18th century, sunflowers were being grown commercially in Europe and North
America. Today, sunflowers are grown in many parts of the world, including North
America, Europe, Asia, and South America. The crop is used for a variety of purposes,
including oil production, birdseed, and confectionery.
3. OBJECTIVES:
3.1. General objective
To increase the productivity and profitability of sunflower by combine effect of
Nitrogen and Boron
3.2.Specific objective
To assess the growth, yield attributing characters and yield of sunflower by applying
different dose of Nitrogen and Boron
To find out the yield gap of sunflower under different doses of Nitrogen and Boron.
4 .STATEMENT OF PROBLEM:
Due to lack of analysis facilities, quality control of sunflower is not easy. Monitoring
to control the quality of fertilizers has been in progress. The supply of chemical
fertilizers on time is still not guarantee that restricts use on right time and the majority
of farmers cannot afford the costly fertilizers. Frequent change of fertilizers types lose
confidence amongst poor farmers. Optimum dose of micronutrient like boron is still not
known. The farming system both in the hilly and flat land (Terai) is complex, diverse
and predominantly resource poor. Therefore, the agriculture productions and
productivity are largely determined by the nutrient factor.
5.JUSTIFICATION OF STUDY:

4. Farmers apply nutrients on their fields like nitrogen and boron necessary to grow and
produce the food we eat. However, when nitrogen and boron are not fully utilized by
the growing plants, they can be lost from the farm fields and negatively impact air and
downstream water quality. This excess nitrogen and boron can be washed from farm
fields and into waterways during rain events and when snow melts, and can also leach
through the soil and into groundwater over time. High levels of nitrogen and boron can
cause eutrophication of water bodies. Eutrophication can lead to hypoxia (“dead
zones”), causing fish kills and a decrease in aquatic life.
6. LITERATURE REVIEW
N is essential for sunflower grain production and oil extraction (Rasool, Hassan, &
Jahangir, 2013). Abdel-Motagally and Osman (2010) observed how increased soil N
through fertilization influenced several growth parameters (plant height, stem diameter,
head diameter, 100-seed weight, seed yield plant-1, seed yield ha-1 and oil yield ha-1),
causing production increases. N fertilization affects many important agronomical
parameters such as leaf area, capitulum diameter, achenes weight and yield (Ali &
Noorka, 2013). According to the dosage of N used, either decreases or increases in oil
yield may be reported.
In addition to N, Boron (B) is also an essential nutrient for plant growth. This
micronutrient has been associated with various plant functions, such as water
availability, sugar translocation, anion and cation uptake, N, phosphorus (P),
carbohydrate and lipid metabolism (Al-Amery, Hamza, & Fuller, 2011). Sunflower is
sensitive to nutrient shortages and can also be used as a tool for evaluating soil B
availability (Oyinlola, 2007). Beneficial effects of major B doses used for sunflower
productivity include: increases in achenes production (Lima et al., 2013), increases in
oil extraction (Tahir, Ashraf, & Ibrahim, 2013), pollen viability (Krudnak, Wonprasaid,
& Machikowa, 2013), and increases in photosynthetic activity and total fresh weight
(Zahoor et al., 2011).
7. MATERIALS AND METHODS
7.1 Features of Experiment:
Crop : Sunflower
Variety : Sunflower 231 (Hybrid)
Design of experiment : RCBD (Double Factorial)

5. Total treatment = 9
Replication = 3
Plot size : 9 m2
Plot to plot distance : 0.5 m
Replication to replication distance : 1m
Seed rate : 10 kg/ha
Spacing: R*R = 60cm , P*P = 20cm
Duration : Feb 2023 to May 2023
7.2 Site selection:
The experiment was conducted in the farm of local farmer located at Lamahi
municipality of Dang district of lumbini province .Geographically it is located at 27.97
N latitude and 82.48E longitude at elevation of about 725m.
The cropping pattern of experimental field was rice - winter legumes- maize sequence
in last two years (2020 and 2021) .The field was at fairly good condition in aspect of
fertility and various soil properties.
7.3 Experimental details
The experiment was conducted in farm of one of local farmer with two factors
Randomized Complete Block Design( RCBD) with three replications .The main
objectives of this experiment was to study the combined effect of nitrogen and boron
application in the growth and yield of Sunflower .The treatment combinations ,plot size
,layout ,etc will be discussed below
7.3.1 Experimental design and treatment factors
The experiment was conducted in 3 by 3 factorial RCBD with three replications and
nine treatment combinations (Table 2).Following were two factors and their
levels(Table 1)
Table 1: Factors and their levels
Nitrogen kg (NPK/ha) Boron (kg/ha)
80:40:20(N1) 0 (B1)

6. 60:40:20(N2) 2(B2)
40:40:20(N3) 4(B3)
Table 2: Different treatment combinations used in experiment .
Treatment combination Nitrogen kg (NPK/ha) Boron(kg/ha)
T1 80:40:20 0
T2 80:40:20 2
T3 80:40:20 4
T4 60:40:20 0
T5 60:40:20 2
T6 60:40:20 4
T7 40:40:20 0
T8 40:40:20 2
T9 40:40:20 4
7.3.2 Field Preparation and Layout
The experimental plot was ploughed two times by M.B plough and then pulverized by
Rotavator one week before sowing .Flooding was done a week before primary tillage
to ensure suitable moisture for germination. The field was finally inspected for any kind
of stubbles of previous crop ,weeds ,etc. The field was then divided into different
experimental plots according to the layout plan where individual plot length and breadth
was maintained as 4.5 m ×2 m .The space between blocks was 1 m while space between
plots was maintained as 0.5 m.
N
E
W

7. T4
T8
T6 T1 T3
T5 T9
T8
T1
T9 T5 T2
T7
T8
T2
T2
T6
T9
T3
T4
T7
T4
T6
T7
T1
T5 T3
0.5m
1m
R1
R2
R3
Fig 1: Layout of experiment
field
S

8. 7.3.3 Manure and fertilizer application
Fertilizer Nitrogen and Boron were applied as indicated above in the respective plots
of the block. Full dose of Boron and Half dose of nitrogen were applied as basal dose
in seed rows at depth of 7-10cm and then remaining half dose of N was applied in
flowering stage.
7.3.4 Seed rate and sowing
The required amount of seeds for each plot was calculated using the recommended
seed rate i.e. 15 kg /ha .Bold and disease free seeds were used for sowing .Seeds were
manually sown in a 60 cm × 20 cm spaced line and by opening a furrow at 5-8 cm depth
on flat beds .Sowing was done on 14 February 2023. A space of 15 cm each was
maintained between border rows and bunds forming 7 number of rows in each
plot.similarly a space of 10 cm was maintained between first seed and last seed in a row
with bund .So, a total of 9 seeds were sown in a row.
7.3.5 Weed management
Weeding was concentrated particularly on 30th
DAS and then second one in 50th
DAS.
No chemical control was applied instead hand weeding and hand hoeing was done
.Eathing up was carried out on 30th
DAS to support for plant stand and facilitate
drainage
15 cm 60cm
4.5 m
2
m
Fig 2: Layout of individual plot
INDEX
------ = Row
= Border

9. 7.3.6 Irrigation management
Irrigation was applied forming ridges and furrows. Following were irrigation performed
in the field:
a. Pre-sowing irrigation
b. Life irrigation
c. 20th day after sowing
d. Early bud development
e. Flowering -2 irrigations
f. Seed development -2 irrigations
7.3.7 Harvesting and Threshing
The head was harvested at maturity stage of crop on 15 May, 2023 .The selected five
plants of each plots were harvested separately. Seeds were separated manually from the
heads separately for each plot .Remaining head harvested in bulk for determining
achene yield .
8. Observations recorded
8.1 Growth attributes
a. Plant height
Five plants were selected at random from each plot and then their heights were
measured in cm with measuring tape, and then averaged at the time of harvesting. The
height of 5 plants were measured on 15th April, 311st
April and 15th
May
b. Stem diameter
Same five plants were used to determine stem diameter at base, middle and top of each
stem and then averaged at the time of harvesting. The diameter of 5 plants were
measured using vernier callipers at base, middle and top of each stem on 15th April,
311st
April and 15th
May
6.3.2 Yield attributes
a. Achenes/head
After threshing, the heads of five randomly selected plants were separated and
accounted for total achenes in these heads and then averaged per head.
b. 1000 grain weight

10. From the seed lot of every plot, each of 1000- achenes were randomly selected and then
recorded their weight using weighing balance.
c. Economic yield(t/ha)
It was calculated using yields of each plot.
8.2 Statistical analysis
All the data of experimental plots were analyzed using ANOVA .When the F-test
indicated statistical significance at p = 0.05 level LSD was used to compare the
difference of the means with 5% level of significance . Microsoft excel was used for
data entry while data was analyzed using R-studio.
Table 3:ANOVA skeleton
SOV Df SS MSS F-calculated F-tab at 5%
Replication 2
Treatment 8
Nitrogen(a) 2
Boron(b) 2
Interaction(a×b) 4
Error 16
Total 26
8.3 Calender of operations
Table 4: Activities along with their date of operations
S.N Activities Date of operations
1. Field preparation 5th
Feb
2. Layout 10th
Feb
3. Sowing 14th
Feb
4. Irrigation Pre-sowing (1st
Feb), live ( 20DAS),flowering (20th
March) and post –flowering
5. Weeding 2 times (15th
March ,12th
April)
6. Fertilisation Full dose of P, K and B , half dose of N(14th
Feb),half
dose of N at flowering (20th
March)
7. Harvesting 15th
May
8. Data collection 15th April,311st
April and 15th
May
9. Result and Discussion

11. The growth parameters like plant height, achenes/head, 1000 grain weight EY (ton/ha)
and stem diameter were significantly affected by the application of nitrogen and boron.
Plant Height (cm)
The data pretaining to mean height of sunflower as influenced by treatments at different
stages are presented in table Each increase in level of nitrogen from 40 to 80 kg N/ha
in combination of different concentration of boron significantly increased the plant
height at 90DAS. Maximum plant height was observed at (80kg N/ha + 2kg boron/ha).
Although there is increase in height at different dose of Nitrogen and Boron, there is no
significant difference observed in plant height due to variation in different nitrogen and
boron doses as it was due to its genotype.
Stem Diameter
The data on stem diameter is presented in table . Each increase in level of nitrogen from
40 to 80 kg N/ha in combination of different concentration of boron significantly
increased the stem diameter at 90DAS. Maximum stem diameter was observed at (80kg
N/ha + 2kg boron/ha). Though there is increase in stem diameter at different dose of
Nitrogen and Boron, there is no significant difference between observed in stem
diameter.
90 DAS

12. Treatments Plant height (cm) Stem Diameter (cm)
Factor A: Nitrogen Dose
80:40:20 (N1) 101.05 1.60
60:40:20 (N2) 100.74 1.52
40:40:20 (N3) 98.82 1.45
LSD (0.05) 10.11 0.185
CV% 10.10 12.12
F-test NS NS
Factor B: Boron
No boron (B1) 98.05 1.49
2 kg boron/ha (B2) 104.27 1.56
4 kg boron/ha (B3) 98.30 1.52
LSD (0.05) 10.11 0.185
CV% 10.10 12.12
Mean 100.20 1.52
F-test NS NS
Table 1 : Effect of treatment on Plant height and stem diameter on 90 DAS.

13. Treatments Achenes/head 1000 grain weight EY(t/ha)
Factor A: Nitrogen Dose
80:40:20 (N1) 238c
32.01c
0.50c
60:40:20 (N2) 313.66a
41.92a
0.878a
40:40:20 (N3) 265.33b
34.7b
0.666b
LSD (0.05) 18.57 2.06 0.056
CV% 6.82 5.69 8.23
F-test ** ** **
Factor B: Boron
No boron (B1) 245.11c
34.53b
0.605c
2 kg boron/ha (B2) 306.77a
39.29a
0.800a
4 kg boron/ha (B3) 265.11b
34.81b
0.638b
LSD (0.05) 18.57 2.06 0.056
CV% 6.82 5.69 8.23
Mean 272.33 36.21 0.681
F-test ** ** **
Table 2 : Effect of treatment on achenes/head, 1000 grain weight and EY.
Achenes/head
The above data on achenes per head is presented in table 2. Achenes per head was
significantly varied with treatments. The result showed that highest achenes/head
313.66 was recorded with nitrogen application of N2 treatment (60kg/ha) followed by
N3 and N1. Similarly, the highest achenes/head 306.77 was recorded with boron
application of B2 treatment (2kg/ha) followed by B3 and B1.
1000 Grain Weight
The above data on 1000 grain weight is presented in table 2. 1000 grain weight was
significantly varied with treatments. The result showed that highest 1000 grain weight
41.92 was recorded with nitrogen application of N2 treatment (60kg/ha) followed by
N3 and N1. Similarly, the highest 1000 grain weight 39.29 was recorded with boron
application of B2 treatment (2kg/ha) followed by B3 and B1.
Economic Yield (t/ha)

14. The data on economic yield is presented in table 2. EY (t/ha) was significantly varied
with treatments. The result showed that the highest economic yield 0.878 was recorded
with nitrogen application of N2 treatment (60kg/ha) followed by N3 (40kg/ha) and N1
(80kg/ha) recorded the lowest economic yield. Similarly, the highest economic yield
0.800 was recorded with boron application of B2 treatment (2kg/ha) followed by B3
and B1 treatment has the lowest economic yield.
Treatments Factor B: Boron
Factor A: Nitrogen Dose No boron (B1) 2 kg boron/ha (B2) 4 kg boron/ha (B3)
80:40:20 (N1) 0.391d
0.568c
0.541c
60:40:20 (N2) 0.880ab
0.955a
0.798b
40:40:20 (N3) 0.545c
0.878ab
0.577c
LSD (0.05) 0.097
CV% 8.29
Mean 0.681
F-test *
Table 3 : Interaction Effect of combine action between Nitrogen and Boron
Interaction effect between combined effect of Nitrogen and Boron on yield per
hectare is shown in the table 3. The highest yield was observed for the B2 treatment (2
kg boron/ha) across nitrogen dose N2 (60kg/ha) In general, the application of boron at
2 kg/ha (B2) resulted in higher sunflower yields compared to both no boron (B1) and 4
kg/ha (B3) levels.
10.Conclusion

15. The Nitrogen and Boron doses on Sunflower did not have a significant effect on plant
height and stem diameter, as indicated by the non-significant F-tests. The combined
optimal treatment would be the 60:40:20 nitrogen dose (N2) with 2 kg boron/ha (B2),
as it consistently yielded the highest values for achenes per head, 1000 grain weight,
and yield. The results indicate that the combination of nitrogen and boron has a
significant impact on sunflower growth and yield. Among the nitrogen doses, the
highest yield was obtained with the N2 treatment (60:40:20), while further reduction in
nitrogen dose (N3) led to a decrease in yield. Regarding boron levels, the application
of 2 kg/ha (B2) resulted in the highest yield across all nitrogen doses. To optimize
sunflower production, it is recommended to use the N2 (60:40:20) nitrogen dose and
apply 2 kg/ha of boron (B2).