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American Journal Of Agriculture And Horticulture Innovations  
(ISSN – 2771-2559) 
VOLUME 04 ISSUE 06    Pages: 11-17 

OCLC – 1290679216   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
Publisher: Oscar Publishing Services 

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ABSTRACT 

The main way to increase the yield of sunflower is to grow modern early-ripening varieties adapted to the soil 

conditions of the region for each region. In this scientific article, the main elements of the technology of cultivation of 

oil sunflower as a repeated crop of high-yielding early-ripening varieties have been developed. Sunflower was planted 

as a repeat crop after wheat, and when the planting schemes were used correctly, increased leaf area had a positive 

effect on yield. As the feeding area increased, the number of leaves increased and the highest value was observed in 

the planting scheme of 70x35–1. Dilbar variety of sunflower produced more leaves than all three cultivars in all planting 

schemes in terms of leaf number index due to its large leaves and high yield. 

 

KEYWORDS 

Sunflower, predecessor, economic signs, repeat, crop, scheme, oil, variety, yield, seed, seedling, early-ripening, 

productivity, leaf, basket. 

 

INTRODUCTION

Sunflower oil is mainly used in food. It is yellow in color, 

shiny, semi-dry (Iodine number 119-144), the seed 

contains 29-56% oil and 15% protein. The oil contains up 

to 62% biologically active menolic acid, vitamins A, D, E, 

K, phosphatides. Sunflower oil is rich in linoleic and 

oleic, unsaturated fatty acids. These oils are similar in 

quality to olive oil. When planting sunflower as a 

repeated crop, it is important to make efficient use of 

wheat-free land, to correctly define planting schemes, 

  Research Article 

 

PHOTOSYNTHETIC ACTIVITY OF SUNFLOWER CULTIVARS IN DIFFERENT 

SOWING SCHEMES 
 

Submission Date: June 01, 2024, Accepted Date:  June 06, 2024,  

Published Date: June 11, 2024 

Crossref doi: https://doi.org/10.37547/ajahi/Volume04Issue06-03 

 

 

Togaeva Sarvinoz Suyunovna  
PhD of Tashkent State Agrarian University, Uzbekistan 

Journal Website: 

https://theusajournals.

com/index.php/ajahi 

Copyright: Original 

content from this work 

may be used under the 

terms of the creative 

commons attributes 

4.0 licence. 

 

https://theusajournals.com
https://doi.org/10.37547/ajahi/Volume04Issue06-03
https://doi.org/10.37547/ajahi/Volume04Issue06-03


Volume 04 Issue 06-2024 12 

                 

 
 

   
  
 

American Journal Of Agriculture And Horticulture Innovations  
(ISSN – 2771-2559) 
VOLUME 04 ISSUE 06    Pages: 11-17 

OCLC – 1290679216   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
Publisher: Oscar Publishing Services 

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to develop and implement intensive land use methods 

in order to get crops twice a year. 

The level of the problem studied. According to 

I.D.Tkalich (2011), removing half of the leaves from the 

upper part of the sunflower stem at the time of basket 

formation caused a 72% reduction in yield, and 

removing leaves from the lower part reduced the yield 

by 23.7%. The photosynthetic productivity of the lower 

leaves is used for the formation of roots and stems at 

the beginning of the growing season, but leads to early 

death due to shading, diseases and drought [5, 6]. 

Small xeromorphic leaves in the upper and partly 

middle parts of the sunflower stem under severe 

drought conditions, the rapid death of the lower leaves 

can then be compensated by the reduction of the 

transpiration surface of the leaves in the upper part of 

the stem. However, the reduction of the leaf level leads 

to a decrease in yield [1, 2, 3]. 

The high productivity of plants is determined by the 

process of photosynthesis, movement of substances, 

accumulation and growth. Organic matter is formed 

during photosynthesis in plants. The morphological 

indicator of the high potential that determines the 

efficiency of plants, in particular, the biometric 

indicators of sunflower: photosynthetic organs 

(leaves) and their number, as well as plant growth 

indicators, is directly related to the size of the diameter 

of the basket. However, it should be recognized that 

linear indicators of plant growth are not always related 

to productivity, sometimes this correlation can be 

negative. 

METHODS 

Experiments were carried out in 2012-2014 in the typical 

sierozem soil conditions of the experimental field of 

the Tashkent State Agrarian University " Center for 

Innovative Developments and Consulting in 

Agriculture". In the experiment, 4 sunflower varieties 

"Jahongir", "Rodnik", "Dilbar" and "Navroz" were 

planted in 4 schemes, 70x20-1; 70x25-1; 70x30-1; It was 

carried out in 70x35-1 planting schemes. 

Placement of field experiments, calculations and 

observations "Methods of conducting field 

experiments" (5), stem height of sunflower varieties 

(at all stages of development), number of leaves per 

plant, leaf surface (A.A.Nichiporovich, 1963), feeding 

area determined by the effect [4, 7]. 

RESULTS AND DISCUSSION 

The main part of the leaves enlarges only before 

flowering, and after flowering, the leaves of the 

baskets at the top of the stem grow. Leaves from 4 to 

11-13 on the stem belong to the lower layer, from 12-13 

to 23-25 to the middle layer, and the leaves located 

above belong to the upper layer. 

Pulling off any healthy leaves will bring up to reduce 

the productivity of the plants. At the same time, the 

leaves in the middle and upper part of the stem are the 

most important in providing nutrients to the seeds at 

the end of the growing season. 

One of the main organs of plants are leaves, which 

carry out the process of photosynthesis in plants and 

produce organic substances. Several factors affect the 

size of the absorptive surface of leaves, one of which is 

the feeding area. The formation of leaves in oil 

sunflower varieties can be seen in table 1. 

In the years 2012-2014, the average number of leaves 

per plant was 23.7 in the 70x20-1 planting scheme of 

Jahangir control variety, 24.0 in the 70x20-1 planting 

scheme, 25.0 in the 70x30-1 planting scheme and 

70x30-1 it was observed that 25.2 units were produced 

in the planting scheme. The fourth variant with a high 



Volume 04 Issue 06-2024 13 

                 

 
 

   
  
 

American Journal Of Agriculture And Horticulture Innovations  
(ISSN – 2771-2559) 
VOLUME 04 ISSUE 06    Pages: 11-17 

OCLC – 1290679216   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
Publisher: Oscar Publishing Services 

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feeding area of 2450 m2 produced more leaves than 

the variants with a small feeding area. This pattern was 

also repeated in the variants of Rodnik, Dilbar and 

Navroz varieties studied in the experiment. The 

number of leaves (25.2, 26.0, 29.2 and 28.1 pieces) was 

observed in the 70x35-1 planting scheme with a large 

feeding area (2450 m2) of all three varieties. Among 

the varieties, it was found that Dilbar and Navroz 

varieties produced more leaves than Rodnik and 

Jahangir varieties. 

The results of photosynthetic activity of sunflower 

varieties in different planting schemes are presented in 

Tables 1 and 2. 

According to the obtained 3-year average data, the leaf 

surface of one plant during the period of star 

formation in the control "Jahongir" variety was 2.6 

thousand cm2 in the 70x20-1 planting scheme, 2.9 

thousand cm2 in the 70x25-1 scheme, 3 in the 70x30-1 

scheme and 3,3thousand cm2 70x35-1 scheme was 

found to be. It can be seen that the variants with small 

feeding area had less leaf surface area and higher in 

variants with large feeding area. In the variant with a 

planting schemes of 70x35-1, compared to the variants 

with a small planting schemes, the leaf surface was 0.3-

0.7 thousand cm2 higher. This scheme was repeated in 

the experimental varieties "Rodnik", "Dilbar" and 

"Navroz". 

In the fourth option in the 70x35-1 planting scheme of 

the "Rodnik" variety, the leaf surface of one plant was 

3.4 thousand cm2, while in the 70x20-1 scheme with a 

small feeding area, it was determined to be 2.7 

thousand cm2, and the leaf surface was 0.7 thousand 

cm2 less. 

Compared to the fourth option in the 70x35-1 planting 

scheme of the "Dilbar" variety, it was found that the 

leaf surface was less by 0.2-0.8 thousand cm2 in the 

options with a small feeding area, and by 0.2-0.8 

thousand cm2 in the same option of the "Navroz" 

variety. 

According to planting schemes, the "Dilbar" variety has 

a higher leaf surface per plant compared to the 

experimental "Jahongir", "Rodnik" and "Navroz" 

varieties. In "Dilbar" and "Navroz" cultivars, indicators 

were observed close to each other, and the highest 

indicator in terms of leaf surface per bush was 

observed in the variant with planting scheme 70x-20-1 

(3.8-3.6 thousand cm2/bush). 

According to the data of the average three-year 

research results presented in the table, one hectare of 

land in the control variety "Jahongir" was 18.3 

thousand m2/ha in the option of planting scheme 

70x20-1, and 16.5 thousand m2/ha in the option of 

planting scheme 70x25-1, 14.2 thousand m2/ha in the 

option with planting scheme 70x30-1; planting scheme 

was 13.3 thousand m2/ha in the option of 70x35-1. 

Compared to the variant with the highest indicator, it 

was found that the leaf surface decreased to 5.0-3.2-

0.9 thousand m2/ha, and the lowest indicator was 

observed in the planting scheme with 70x35-1. 

This observed regularity was repeated in the 

experimental varieties "Rodnik", "Dilbar" and 

"Navroz". Compared to the variant with a 70x20-1 

planting scheme in the "Rodnik" variety, in other 

planting schemes in the experiment, in the following 

order, It was found that it decreased to up to 5.3-3.8-

1.4 thousand m2/ha, in the "Dilbar" variety 5.8-3.3-1.6 

thousand m2/ha, and in "Navroz" variety to 5.5-3.1-1.4 

thousand m2/ha, and the lowest indicator was 

observed in the planting scheme with 70x35-1. 

According to the average three-year research results of 

the leaf surface indicators per hectare of sunflower 

varieties during the star phase formation period, the 



Volume 04 Issue 06-2024 14 

                 

 
 

   
  
 

American Journal Of Agriculture And Horticulture Innovations  
(ISSN – 2771-2559) 
VOLUME 04 ISSUE 06    Pages: 11-17 

OCLC – 1290679216   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
Publisher: Oscar Publishing Services 

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highest indicator was observed in the "Jahongir", 

"Rodnik", "Dilbar" and "Navroz" varieties in the variant 

with a planting scheme of 70x20-1 (18.3 -19.1-21.3-20.6 

thousand m2/ha). It can be seen that the leaf area per 

plant of sunflower was higher in the 70x35-1 planting 

scheme, while the number of seedlings per hectare 

was higher in the 70x20-1 planting scheme. When 

comparing the differences between the varieties 

according to the parameters of the leaf surface per 

hectare, "Dilbar" and "Navroz" varieties had similar 

indicators, and a significant difference was observed in 

the "Jahongir" control variety. According to the 

obtained results, it was found that "Dilbar" variety had 

a higher leaf surface of 0.7-2.2 thousand m2/ha than 

"Navroz" and "Rodnik" varieties. 

It was found out in the research results that when the 

sunflower's development period changes, its leaf 

surface also increases. 

According to the average 3-year data obtained, the leaf 

surface of one plant during the flowering period varies 

according to the planting schemes, and the lowest 

indicator in the control variety "Jahongir" was 

observed in the variant with the planting scheme 

70x20-1, 4.3 thousand cm2 /plant; 4.4 thousand 

cm2/bush in the option with planting scheme 70x25-1; 

4.5 thousand cm2/bush in the option with planting 

scheme 70x30-1; In the planting scheme of 70x35-1, it 

was 4.6 thousand cm2/bush, and as the feeding area 

increases, it was found that the leaf surface exceeds 0.1 

thousand cm2/bush. 

Table 1 

Indicators of leaf surface of oilseed sunflower cultivars during budding period according to variants 

(2012 - 2014) 

N

o 

Planting 

scheme 
Varieties 

Leaf surface oil of sunflower varieties 

according to options, (thousand cm2/ha) 

Leaf surface oil of sunflower varieties 

according to options, (thousand m2/ha) 

years years 

2012 2013 2014 Average 2012 2013 2014 

Ave

rag

e 

1 
70x20-1 

Jahangir (st) 

2,6 2,7 2,5 2,6 
18,3 19,0 17,6 

18,

3 

2 
70x25-1 2,9 3,0 2,8 2,9 

16,5 17,1 15,9 

16,

5 

3 
70x30-1 3,0 3,1 2,9 3,0 

14,2 14,7 13,8 

14,

2 

4 
70x35-1 3,3 3,4 3,2 3,3 

13,3 13,8 12,9 

13,

3 

5 
70x20-1 

Rodnik 

2,7 2,8 2,6 2,7 
19,1 19,9 18,4 

19,

1 

6 
70x25-1 3,0 3,2 3,1 3,1 

16,9 18,3 17,6 

17,

6 



Volume 04 Issue 06-2024 15 

                 

 
 

   
  
 

American Journal Of Agriculture And Horticulture Innovations  
(ISSN – 2771-2559) 
VOLUME 04 ISSUE 06    Pages: 11-17 

OCLC – 1290679216   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
Publisher: Oscar Publishing Services 

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7 
70x30-1 3,2 3,3 3,1 3,2 

15,1 15,8 14,7 

15,

2 

8 
70x35-1 3,4 3,5 3,3 3,4 

13,8 14,2 13,4 

13,

8 

9 
70x20-1 

Dilbar 

3,0 3,1 2,9 3,0 
21,3 22,1 20,6 

21,

3 

1

0 
70x25-1 3,3 3,4 3,2 3,3 

18,8 19,4 18,2 

18,

8 

1

1 
70x30-1 3,6 3,7 3,5 3,6 

17,1 17,6 16,6 

17,

1 

1

2 
70x35-1 3,8 3,9 3,7 3,8 

15,5 15,9 15,1 

15,

5 

1

3 
70x20-1 

Navroz 

2,9 3,0 2,8 2,9 
20,6 21,3 19,9 

20,

6 

1

4 
70x25-1 3,2 3,3 3,1 3,2 

18,2 18,8 17,6 

18,

2 

1

5 
70x30-1 3,5 3,6 3,4 3,5 

16,5 17,1 16,0 

16,

5 

1

6 
70x35-1 3,7 3,8 3,6 3,7 

15,1 15,5 14,6 

15,

1 

 

Table 2 

Indicators of leaf surface of oilseed sunflower cultivars during flowering period according to variants 

(2012 - 2014) 

No 
Planting 

scheme 
Varieties 

Leaf surface oil of sunflower varieties according to 

options, (thousand cm2/ha) 

Leaf surface oil of sunflower 

varieties according to 

options, (thousand m2/ha) 

number 

of 

leaves, 

pcs 

2012 

number 

of 

leaves, 

pcs 

2013 

number 

of 

leaves, 

pcs 

2014 Average 2012 2013 2014 Average 

1 70x20-1 

Jahangir 

(st) 

23,6 4,3 24,5 4,5 23,0 4,1 4,3 30,4 31,8 30,0 30,7 

2 70x25-1 23,9 4,5 24,7 4,6 23,5 4,2 4,4 25,7 26,3 24,0 25,3 

3 70x30-1 24,7 4,6 25,2 4,7 25,0 4,3 4,5 21,9 22,3 20,5 21,6 

4 70x35-1 24,9 4,7 25,4 4,8 25,2 4,5 4,6 19,1 19,5 18,3 19,0 

5 70x20-1 Rodnik 23,6 4,5 24,7 4,6 24,2 4,3 4,5 32,0 32,7 30,6 31,8 



Volume 04 Issue 06-2024 16 

                 

 
 

   
  
 

American Journal Of Agriculture And Horticulture Innovations  
(ISSN – 2771-2559) 
VOLUME 04 ISSUE 06    Pages: 11-17 

OCLC – 1290679216   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
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6 70x25-1 24,8 4,7 25,4 4,8 25,0 4,5 4,7 26,8 27,4 25,7 26,6 

7 70x30-1 25,3 4,8 26,6 4,9 25,7 4,7 4,8 22,9 23,3 22,4 22,9 

8 70x35-1 25,4 4,9 26,7 5,1 25,9 4,6 4,9 20,0 20,8 18,7 19,8 

9 70x20-1 

Dilbar 

27,1 5,2 28,2 5,3 28,0 4,9 5,1 37,1 37,8 34,9 36,6 

10 70x25-1 27,4 5,3 28,4 5,4 28,1 5,1 5,3 30,3 30,9 29,1 30,1 

11 70x30-1 28,6 5,4 29,5 5,6 29,0 5,3 5,4 25,7 26,7 25,2 25,9 

12 70x35-1 28,7 5,6 29,7 5,7 29,2 5,5 5,6 22,8 23,3 22,4 22,8 

13 70x20-1 

Navroz 

24,6 4,8 25,7 5,0 25,1 4,7 4,8 34,2 35,7 33,5 34,5 

14 70x25-1 26,5 5,1 27,4 5,2 27,0 5,0 5,1 29,1 29,7 28,5 29,1 

15 70x30-1 27,3 5,2 28,5 5,4 28,2 5,1 5,2 24,7 25,7 24,2 24,9 

16 70x35-1 27,4 5,4 28,6 5,5 28,4 5,3 5,4 22,0 22,4 21,6 22,0 

 

This regularity was repeated in other varieties studied 

in the experiment and was observed in the planting 

scheme with the highest leaf level of 70x35–1. It was 

found that in the variant with planting scheme 70x20-

1, in all varieties (4.3, 4.5, 5.1 and 4.8 thousand cm 2 

/plant), one plant has less leaf surface. According to the 

varieties, a high rate was observed in the "Dilbar" 

variety. In this case, the lowest indicator was observed 

in the variant with planting scheme 70x20-1, 5.1 

thousand cm2/bush; 5.3 thousand cm 2 /bush in the 

option with planting scheme 70x25-1; 5.4 thousand 

cm2/bush in the option with planting scheme 70x30-1; 

In the planting scheme of 70x35-1, it was found to be 

5.6 thousand cm 2 /bush, which had the lowest 

indicator, and compared to the first option, it increased 

by 0.2-0.5 thousand cm2/bush. 

In "Jahongir" variety, with the 70x20-1 planting 

scheme, the surface of leaves per hectare was 30.7 

thousand m2/ha, while the surface of leaves decreased 

as the feeding area increased. 

Compared to the first option with the highest index, 

the number of feeding areas increased by 5 cm in the 

following sequence was determined to be reduced to 

2.6-6.3-11.7 thousand m2/ha, and the lowest index was 

observed in the planting scheme with 70x35-1. 

This observed regularity was repeated in the studied 

varieties and planting schemes in the experiment, and 

it was found that in the "Rodnik" variety, compared to 

the variant with the planting scheme of 70x20-1, it 

decreased to 3.1-6.8-12.0 thousand m2/ha in the 

following sequence. 

The planting scheme of "Dilbar" variety was 36.6 

thousand m2/ha in the variant of 70x20-1, and 30.1 

thousand m2/ha in the variant of planting scheme 

70x25-1; 25.9 thousand m2/ha in the option with 

planting scheme 70x30-1; planting scheme was 22.8 

thousand m2/ha in the option of 70x35-1. 

The planting scheme of the "Navroz" variety was 34.5 

thousand m2/ha in the 70x20-1 variant, and 29.1 

thousand m2/ha in the 70x25-1 variant; 24.9 thousand 

m2/ha in the option with planting scheme 70x30-1; 

planting scheme was 22.0 thousand m2/ha in the 

option of 70x35-1. 

According to the average three-year research results of 

sunflower varieties on leaf surface indicators per 



Volume 04 Issue 06-2024 17 

                 

 
 

   
  
 

American Journal Of Agriculture And Horticulture Innovations  
(ISSN – 2771-2559) 
VOLUME 04 ISSUE 06    Pages: 11-17 

OCLC – 1290679216   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
Publisher: Oscar Publishing Services 

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hectare, the highest indicator was observed in the 

"Jahongir", "Rodnik", "Dilbar" and "Navroz" varieties 

in the variant with the planting scheme 70x20-1 (30.7-

31, 8-36.6 and 34.5 thousand m2/ha). It can be seen that 

leaf area per plant was higher in 70x35-1 planting 

scheme, whereas it was observed that leaf area per 

plant was higher in 70x20-1 planting scheme in terms of 

number of seedlings per hectare. When comparing the 

differences between the varieties according to the 

parameters of the leaf surface per hectare, the "Dilbar" 

and "Navroz" varieties had similar indicators, and a 

significant difference was observed in the "Jahongir" 

variety. According to the obtained results, it was found 

that "Dilbar" variety had a higher leaf surface area of 

2.1-5.9 thousand m2/ha compared to "Navroz", 

"Jahongir", "Rodnik" varieties. 

CONCLUSIONS 

In all varieties used in the experiment, the number of 

leaves increased as the feeding area increased, and the 

highest value was observed in the planting scheme of 

70x35–1. Due to the fact that the leaves of the 

sunflower variety "Dilbar" were large and produced a 

lot, it produced more leaves than all three varieties in 

terms of the number of leaves (27.8 - 29.2 pieces/bush) 

in all planting schemes. 

As the feeding area of sunflower varieties increased, 

the leaf surface of one plant increased. Among the 

sunflower varieties, the highest rate was observed in 

the "Dilbar" variety (5.6 thousand cm2 /plant). 

"Jahongir" was 0.2-1.0 thousand cm2/bush higher than 

"Rodnik" and "Navroz" varieties. According to the data 

obtained on the leaf surface per hectare during the 

sunflower flowering period, due to the decrease in the 

number of plant stems per hectare, the highest leaf 

surface index in all varieties was observed in the variant 

with the planting scheme 70x20-1 (30.7-31.8-36.6-34.5 

thousand m2/ha). 

Among the sunflower varieties, the highest rate was 

observed in the "Dilbar" variety (36.6 thousand m2/ha). 

It was found that "Jahongir" was higher than "Rodnik" 

and "Navroz" varieties by 5.9-2.1 thousand m2/ha. 

REFERENCES 

1. Anarboev I.U. Prospects of growing oil crops in our 

republic - new technologies aimed at growing oil 

and fiber crops in Uzbekistan and increasing their 

productivity, Republic science. A collection of 

conference articles, T. 2009. P.6-7. 

2. Anorboev I., Orolov Kh. Oil crops //Sunflower. 

Agriculture of Uzbekistan. J. 2009. No. 2. P.10-11 

3. Azizov.T., Anarbaev I., Tukhtaeva S. // J. Agriculture 

of Uzbekistan. 2013. No. 6. P.5-6. 

4. Methods of conducting field experiments T-2007. 

P. 133-138. 

5. Tkalich I.D., Demidov A.A. Methods of sowing 

sunflower // Visn. agrarian Science.1999. No. 5. 

P.22-25, 85-87. 

6. Tkalich I.D. Flower of the sun (basics of biology and 

agricultural technology of sunflower) // 

Dnepropetrovsk, 2011. P.172 

7. Nichiporovich A.A. Photosynthesis and issues of 

plant productivity. - M.: Nauka, 1963. P.457.  

 


