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8 Effect of Fertilizer and Growth Regulator on Yield and Yield Attributing Characters of
9 Cotton Under High-Density Planting System

10 Abstract
11 The present study was carried out to evaluate the effect of growth retardant and nitrogen levels
12 on growth and development of cotton under high density planting system (HDPS). Three levels
13 of each nitrogen and growth regulators were studied across two cotton genotypes for three
14 consecutive years (Kharif-2019, 2020 and 2021). Thee experiment was laid out with SPD design
15 under three replications at Main Cotton Research Station, NAU, Surat. The result showed that
16 the Plant height, No. of sympodia at harvest, mean length of sympodia were significantly
17 deviated due to fertilizer level; as well as plant height, mean length of sympodia, and plant width
18 were significantly deviated due to genotypes. The significantly lower plant height as well as
19 length of sympodia was recorded under lower fertility (100 % RDF) than higher fertility (125%
20 and 150 % RDF), whereas genotype GISV-272 had significant higher plant height and No of
21 sympodia r under higher fertility level (150 % RDF). However, genotype GSHV-180 had
22 significant lower plant width. Plant height, mean length of sympodia, and plant width that
23 showed significant deviation due to mapiquat chloride. Final plant population was non-
24 significant due to either fertilizer level, or genotypes and mapiquat chloride treatments. Bolls per
25 square meter, Boll weight, Seed Cotton Yield was non-significant due to mapiquat chloride
26 treatment. No of bolls per square meter and Seed Cotton Yield were significantly deviated due to
27 fertilizer level and genotypes. No of bolls per square meter and Seed Cotton Yield recorded
28 significantly higher under higher fertility (RDF 150%). No of bolls per square meter was
29 observed significantly higher in GSHV-180, whereas seed cotton yield was significantly higher
30 in GISV-272. Seed cotton yield was observed significantly higher due to higher fertility level.
31 Keywords: High density planting (HDPS); cotton; growth regulator (GR); nitrogen; mapiquat
32 chloride (MC); compact genotype
33 Introduction:
34 Cotton (Gossypium hirsutum L.) plays a significant role in the country’s economic growth by
35 providing substantial employment and contributing significantly to export earnings, and it is
36 referred as ‘White Gold’ or ‘King of Fiber.’ Millions of people are supported directly and
37 indirectly by the farms that grow it, the manufacturing concerns that process it, and the domestic
38 and international marketing activities that distribute cotton products. India is the only country
39 where all four cultivated species of cotton are grown on a commercial scale covering a cultivated
40 area of about 130.5 lakh hectares. It ranks second in cotton production with 52 lakh tonnes
41 among all cotton-producing countries following China (1).
42 In the global cotton scenario, China has been the leading producer of cotton in recent
43 decades. India was a leader in cotton production for a few years in the last decade. However,
44 China has re-established its position as the leading producer of cotton in the world since 2018-
45 19. Between 2006 and 2018, the average cotton productivity in the country was above 500 kg/ha,
46 but from 2019 to 2023, productivity slumped, hovering around an average of 440 kg/ha (1).
47 Increasing demand of fiber day by day, it is essential to improve productivity of cotton to meet
48 the requirement of cotton and reduce the economic burden by decreasing import.
49 Despite the introduction of improved hybrids over the years, we have started witnessing
50 the plateauing of yield levels and decreasing productivity from 2014 to 2024. One alternative
51 option to break this plateau and to increase productivity levels is through exploring compact
52 plant architecture for higher planting densities (2-3). In high density planting system, plant
53 population per unit increased by narrowing down the row –row and plant – plant spacing. Thus,
54 benefits associated with increased surface residues may also affect fertilizer N application rates
55 for subsequent crops. Greater fertilizer N rates have been suggested for cereal crops residues to
56 offset potential N immobilization because of high nutrient utilization by high-residue producing
57 crops (4). Scientists observed that increased use of N, P, and K fertilizers could promote dry
58 matter accumulation in all organs of cotton, significantly increasing seed cotton yield by 9.42–
59 81.71% (5-6).
60 However, as planting density increases, individual plants shade each other, decreasing
61 photosynthetic performance due to disturbances in canopy permeability leading to increased
62 square and boll abscission. Adequate growth is beneficial for ventilation and light transmission,
63 as the cotton population adjusts to light interception, the utilization of light energy by leaf area,
64 and the absorption of N, P, and K nutrients by cotton (7-8). Reports have shown that the use of
65 density and growth regulators could significantly regulate nutrient uptake and utilization (5, 9).
66 Plant growth especially the terminal growth of apical buds is influenced by the hormone
67 gibberellin. To reduce plant growth, use of gibberellin biosynthesis inhibitor is suggested (10).
68 Mapiquat chloride is an inhibitor of gibberellin biosynthesis widely utilized for controlling
69 excessive vegetative growth by reducing internode length and, consequently, plant height and
70 leaf area, thus resulting in a more compact plant stature (11-14). Plant growth regulators increase
71 root secretions into the soil and improve the absorption of the cotton root system, hence,
72 promoting the formation of fruiting bodies and larger size. These regulators improve yield and
73 quality by effectively regulating canopy shape, size, and mineral nutrient absorption (15-17). In
74 China, Miantaijin is a growth regulator for cotton, containing N, N-dimethylpiperidinium
75 chloride and 2-N,N-diethylaminoethyl caproate, which is widely used. These products regulate
76 the growth, development and promote the transformation of nutrients from source to sink (5, 18-
77 20).
78 The High Density Planting System (HDPS) in cotton is a highly technical system that
79 requires careful planning, timely planting, vigorous monitoring, and prompt interventions. The
80 HDPS leads to excessively tall plants and increased vegetative growth. Therefore, cotton
 81 production under HDPS necessitates careful consideration of several management strategies,
82 including the use of plant growth regulators, fertilizers, and suitable genotypes (21).
83 Since cotton exhibits an indeterminate growth habit, vegetative and reproductive growth
84 occur simultaneously for a large part of its life cycle. Nevertheless, sufficient vegetative growth
85 is essential to support reproductive growth. Excessive vegetative growth may be the reason for
86 the higher fruit abortion; delayed crop maturity and hence harvesting. Most cotton hybrids
87 exhibit aggressive vegetative growth patterns with high nutrient availability and adequate rainfall
88 or irrigation at the required stages. Uncontrolled vegetative growth can cause fruit and square
89 dropping, delayed maturity, and boll rot, ultimately reducing yield (22).
90 Keeping all these points in mind, an experiment was conducted to evaluate the influence
91 of plant growth regulators and fertilizer levels on cotton under a high-density planting system.
92 Material and Methods:
93 The experiment was conducted at the Main Cotton Research Station, Navsari Agricultural
94 University, Surat. The experimental site lies at a cross point of 21° - 17′ N latitude and 72° – 80′
95 E longitude at an elevation of 11.34 meters above the mean sea level. Soil is well-drained clayey,
96 typical black cotton soil having predominant montmorillonite clay minerals by its origin and is
97 medium in fertility.
98 The experiment was laid out as per the SPD design with three replications. Three
99 nitrogen level (N) i.e. N1: 100% RDF (recommended dose of nitrogen i.e. 240 kg nitrogen),
100 N2:125% RDF and N3:150% RDF were taken as the main plot and two compact genotypes (V1:
101 GISV-272 and V2: GSHV-180) as well as three treatment of growth regulators viz., G1: Control,
102 G2: Mapiquat chloride spray at rate of 20g.ai per hectare at 60 DAS and G3: Mapiquat chloride
103 spray at rate of 20g.ai per ha at 60 DAS and 75 DAS were applied as sub treatment. The plant
104 spacing 60 x 15 cm was kept to accommodate 111111 plants per hectare. The plants were sown
105 on the ridge with the commencement of the monsoon. The two intercultural and two hand
106 weeding were carried out. The trial was conducted in the rainfed condition.
107 The observations for the Plant height, number of sympodia, mean length of sympodia,
108 number of monopodia and Shoot: Root ratio were taken from five randomly selected plants from
109 each plot with standard practices. The leaf area index for each treatment was worked out using
110 the following formula as proposed by Watson (23).

111 LAI

112 The boll weight was calculated as an average weight of 50 bolls. The number of bolls
113 was taken as per square meter, The Seed cotton yield per hectare was calculated from the net
114 plot. The statistical analysis was carried out using the standards program.
115 Result and discussion:
116 Effect on plant height and monopodia
117 The plant height significantly deviated every year and pool due to nitrogen doses. Significant
118 higher plant height was observed in treatment 150% RDF fertilizer which was at par with
119 treatment 125% RDF. As higher fertilizer promotes the growth of plant the plant height showed
120 higher in 150% RDF fertilizer. Similar results were stated by two group of scientist in cotton, as
121 plant attains higher height as the nitrogen level increases (24-26). However, genotypes were non-
122 significant for plant height during 2020-21 and 2021-22 as well as pooled analysis. The mapiquat
123 chloride was significantly affected the plant height in pooled and during 2019-20 and 2021-22.
124 The significant lower plant height was observed when plant is treated with mapiquat chloride at
125 rate of 20 g.ai per ha at 60 DAS and 75 DAS, which was followed by mapiquat chloride spray at
126 rate of 20g.ai per hectare at 60 DAS. The mapiquat chloride is a gibberellic acid inhibiter and
127 hence reduce the height of cotton plant. The application of mapiquat chloride results in a
128 decrease in plant height (14, 27-28).
129 The number of monopodia are the non-fruiting branch of cotton. The monopodia showed
130 non-significant effect for nitrogen and mapiquat chloride in pooled however genotype showed
131 significant deviation. The non-significant influence of mapiquat chloride on monopodial
132 branches was also observed by Brijal and Dhamodharan individually (27, 29). The genotype
133 GSHV-180 showed significantly higher monopodia as compare to GISV-272 however it is under
134 limit as it was below 0.5 per plant.
135 Effect on sympodia
136 The data for number of sympodia and Length of sympodia were presented in Table 2. The
137 number of sympodia was non-significant for all the year and pooled analysis for all treatment
138 except due to nitrogen level in Kharif-19. However, Length of sympodia was significantly
139 affected due to nitrogen levels. The increase in the nitrogen does lead to increase in the length of
140 sympodia. The nitrogen has positive relation with the length of sympodia. The positive relation
141 of nitrogen application and length of sympodia also observed by Ibrahim (25). The spray of
142 mapiquat chloride showed significant effect on length of sympodia in pooled analysis. The spray
143 of mapiquat chloride significantly reduced the length of sympodia as compared to the control.
144 The length of sympodia decreased as the number of spray increased. The interaction was
145 significant for the mapiquat chloride and genotypes as well nitrogen and genotypes in pool
146 analysis. It showed that the genotypes have different potential for the nitrogen and mapiquat
147 chloride metabolism with respect to length of sympodia. The genotype showed non-significant
148 deviation in pooled analysis. The higher sympodial length was observed when higher nitrogen
149 was applied while mapiquat chloride application significantly reduced sympodial length.
150 Researcher reviewed similar results and stated that the canopy structure becomes more compact
151 due to the application of MC (13). However, other group also found that the sympodial branches
152 and sympodial length increased in Bt hybrid cotton when MC is applied (27).
153 These showed that opposite effect of each chemical for sympodial length. Hence, this
154 combination of treatment might be useful for diversion of nutrients towards the reproductive part
155 instead of the vegetative parts of the cotton plant.
156 Effect on shoot:root ratio and leaf area index (LAI)
157 Shoot root ratio was non-significant due to nitrogen in individual year however it was
158 significantly deviated due tonitrogen levels and genotypes. The growth regulator showed
159 significant effect on shoot to root ratio in individual year as well as in pooled. The result
160 indicated that higher nitrogen doses lead to lower shoot:root ratio. Water and Nitrogen
161 application can also affect root growth or distribution. The root shoot ratio was significantly
162 deviated due to nitrogen. Chen et al., found that H20W75N1 increased root diameter resulted in
163 the development of effective roots (diameter less than 0.05 mm) to efficiently uptake and
164 transport. These changes protect the integrity of the lipid membrane in the root and enhanced
165 root stress tolerance in the 0–80 cm soil layers at 82 and 102 DAE in their experiment. A
166 possible reason was that H20W75N1 increased the available water and nitrogen in the soil layer,
167 while higher available water and nitrogen also promoted the nitrogen reductase content and the
168 root protective enzyme and hence more efficient water and N uptake (30). Likewise, mapiquate
169 chloride also reduced the shoot:root ratio, which indicate that root length was less effected due to
170 mapiquate chloride as compared to plant height. The MC downregulates GhEXP and GhXTH2
171 and ultimately inhibits internode elongation (37). Among the genotype GSHV-180 showed
172 significant higher shoot: root ratio. The interaction was significant among all three variables that
173 indicates that the effect of level of nitrogen and mapiquat chloride on genotypes was
174 interdependent (Table-3).
175 Leaf area index (LAI) was significantly deviated due to nitrogen levels. The higher
176 nitrogen dose significantly increased the LAI indicating that nitrogen promotese growth of cotton
177 plant. The mapiquate chloride spray significantly affected the LAI in individual years as well as
178 in pooled (Table 3). The spray of mapiquat chloride has a significant effect on LAI. The single
179 spray did not show much influence; however, two sprays of mapiquat chloride at 60 DAS and 75
180 DAS significantly reduced LAI. The Shahbaz stated that the foliar application of MC in cotton
181 plants gave rise to arrested leaf growth and decreased leaf area with considerably lower levels of
182 GA4 (31), which is in-line with our outcomes. Treatment, which included mepiquat chloride,
183 potassium nitrate (KNO₃), Naphthalene acetic acid (NAA), calcium borate (Ca 3(BO3)2), and
184 defoliant, achieved asatisfactory leaf area index, fewer functional leaves and ideal plant height.
185 This balanced growth pattern makes the plants more suitable for mechanical harvesting (32),
186 indicating that more than one growth regulator is required for canopy management in mechanical
187 picking of cotton. The interaction of nitrogen levels and genotypes showed a significant effect,
188 showing that nitrogen response was varied with genotypes for LAI (Table-3).
189 Effect on boll weight and number of boll
190 Boll weight was non-significant for nitrogen levels however the increase in nitrogen levels
191 numerically increase boll weight. It revealed that after certain level, increase in nitrogen dose,
192 increase in boll weight showed plaque. The scientist showed significant higher boll weight when
193 125% nitrogen was applied as compared to 100% and 75% (25). The 20% reduction in Nitrate
194 (N264) did not decrease boll weight under high density but decreased it by 3.2% under low
195 density (33). Hence, optimum nitrogen lead to higher number of bolls. The genotypes were
196 significantly deviated for boll weight for individual year as well as pooled. GISV 272 showed
197 significant higher boll weight than GSHV-180. The mapiquate chloride spray showed a
198 significant effect on boll weight. Boll weight was shown significantly higher due to mapiquate
199 chloride spray as compare to control (Table-4). The similar results were obtained by the Patel
200 and coworkers (27).
201 The number of boll per square meter was recorded and presented in Table-4. The pooled
202 analysis showed that nitrogen level showed significant effect on number of boll. The result
203 revealed that number of bolls was significantly higher when 150% RDN was applied which was
204 followed by 125% RDN. The researchers recorded significantly higher number of boll when
205 125% and 100% nitrogen was given as compared to 75% nitrogen this might be attributed to
206 nitrogen fertilizer because the cotton plant is especially vulnerable to nitrogen absorption (25).
207 Likewise, the maximum number of bolls may be attributable to enhanced photosynthate
208 assimilation and translocation. These findings were comparable to Sisodia and Khamparia (34).
209 The genotypes exhibited significant variation for number of bolls per square meter. The GSHV-
210 180 showed significant higher number of boll as compared to GISV 272. The spray of mapiquat
211 chloride non significantly affected the number of bolls. However, Numeracally reduction in
212 number of boll per square meter was observed. The number of bolls was significantly reduced
213 when 0.015% mepiquat chloride (MC) sprayed at square formation and boll development stage
214 (39). The interaction for the all three variables showed significant effect, which revealed that the
215 effect of nitrogen level and mapiquat chloride varied with the genotype. Patel and his team
216 workers obtained significantly higher number of boll in cotton treated with mapiquat chloride
217 (27). Shahbaz reported that MC application reduced the number of boll under drought condition
218 and stated that the effect of MC is variable due difference in environment condition (31).
219 Effect on seed cotton yield
220 The seed cotton yield was significantly deviated due to nitrogen levels. The higher the nitrogen
221 level (150% RDN) showed the significant higher seed cotton yield which was at par with the
222 125% RDN.The result showed that nitrogen is very essential for the higher yield in the HDPS
223 cotton. However, the increase was at par with higher dose hence, 125% RDN is recommended
224 for the HDPS cotton. The research showed that yield attributing characters along with seed
225 cotton yield is increased with increased nitrogen level to the critical level (25, 35, 36). The
226 genotypes showed significant deviation in seed cotton yield. The significant higher seed cotton
227 yield was observed for the genotype GISV-272 as compared to GSHV-180. The mapiquat
228 chloride were non-significant for seed cotton yield in every year as well as pool analysis. It may
229 useful for the management of the growth of cotton plant but we have not observed any impact on
230 seed cotton yield in this experiment (Figure 1). Patel and coworkers obtained significantly higher
231 seed cotton yield treated with mapiquat chloride (27). Guand coworker found that MC
232 applications reduced plant canopy with variable yield responses (13). Shahbaz Atta concluded
233 that yield responses to MC spray is influenced by many conditions such as application rate, plant
234 stages, genotypes, site-specific conditions, and changeable climate conditions (40). Afzal MN
235 and his team concluded that the interaction of pant density and level of nitrogen was non-
236 significant for lint mass and fiber quality. It was observed that low dose nitrogen led to
237 maximum agronomic and economic nutrient use efficiency and partial factor productivity (PFP).
238 However, the percent relative yield (PRY) at 50 kg N was very low in relevance to 150 kg (39).
239 Conclusion:
240 Based on our findings in the present work, we conclude that the application of nitrogen at 150 %
241 RDN (337 kg) increased the growth of cotton plant i.e. plant height, length of sympodia and LAI
242 as well as number of bolls and seed cotton yield. However, the increase in seed cotton yield was
243 higher in 150% RDN (337 kg) that was also found on par with 125% RDN (281 kg) hence it is
244 recommend to use 125% RDN for HDPS cotton. Interestingly, GISV 272 showed higher seed
245 cotton yield than GSHV 267 revealing the established fact of genotype dependent response to
246 nitrogen application. Further, the seed cotton yield was not significantly effected by mapiquat
247 chloride neither at 20g.ai/ha at 60 DAS nor at 20g a.i/ha at 60 DAS and 75 DAS. However,
248 mapiquat chloride (20g.ai/ha) this dose of mapiquat chloride and time of application reduced
249 plant height, shoot root ratio, LAI and length of sympodia of cotton under HDPS. Hence,
250 mapiquat chloride is useful for the control of vegetative growth of cotton.
251 Further research:
252 Time of application and doses can be tested for increase in seed cotton yield along with control
253 of vegetative growth. Some new molecules or combination of molecules should be researched
254 and tested for desired source sink manipulation to achieve goal of seed cotton yield.
255
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387 00276-0
388 Table 1. Effect of nitrogen and growth regulators on plant height and number of
389 monopodia of cotton genotypes.
Plant height (cm) at harvest No of monopodia
Treatment 2019-20 2020-21 2021-22 Pooled 2019-20 2020-21 2021-22 Pooled
N1 91.9 146.3 136.8 125.0 0.78 1.04 0.98 0.93
N2 108.3 156.4 143.4 136.0 0.78 1.08 0.87 0.91
N3 102.8 157.9 150.8 137.2 0.80 1.08 1.03 0.97
S.Em.± 1.48 1.19 2.12 1.96 0.02 0.07 0.02 0.03
C.D. at 5 % 5.81 4.67 8.03 7.71 NS NS 0.08 NS
V1 103.8 153.1 144.7 133.9 0.74 0.96 0.87 0.86
V2 98.3 154.0 142.7 131.7 0.84 1.17 1.05 1.02
S.Em.± 1.33 2.37 1.44 0.81 0.03 0.05 0.02 0.02
C.D. at 5 % 3.8 NS NS NS 0.09 0.13 0.07 0.06
G1 107.9 156.2 157.9 140.7 0.81 0.98 0.92 0.91
G2 99.7 153.5 140.1 131.1 0.78 1.08 0.90 0.92
G3 95.5 151.0 133.0 126.5 0.77 1.13 1.06 0.99
S.Em.± 1.62 1.68 1.77 1.69 0.04 0.06 0.03 0.03
C.D. at 5 % 4.70 NS 5.1 4.77 NS NS 0.09 NS
NV NS NS NS NS NS NS NS NS
NG 8.14 8.40 NS NS NS NS NS NS
VG 6.65 6.86 NS NS NS NS NS NS
NVG NS 11.88 NS NS NS NS 0.21 NS
YNV NS NS
YNG 8.3 NS
YVG 6.7 NS
YNVG 11.7 NS
CV% 5.4 19.71
390 Number of monopodia value are sinarc transformed and analysed

391 Table 2. Effect of nitrogen and growth regulators on sympodia of cotton genotypes.

No of sympodia Length of sympodia

Treatment 2019-20 2020-21 2021-22 Pooled 2019-20 2020-21 2021-22 Pooled
N1 16.6 21.1 20.4 19.4 24.36 28.72 32.67 28.58
N2 19.1 21.3 21.2 20.5 26.47 30.03 34.72 30.41
N3 18.6 20.1 22.3 20.3 27.78 32.72 37.52 32.67
S.Em.± 0.3 0.45 0.4 0.58 0.37 0.39 0.58 0.27
C.D. at 5
1.17 NS NS NS 1.45 1.53 2.28 0.81
%
V1 18.0 20.5 22.0 20.2 27.28 31.28 33.70 30.75
V2 18.2 21.1 20.7 20.0 25.13 29.70 36.23 30.36
S.Em.± 0.5 0.48 0.49 0.29 0.70 0.41 0.89 1.04
C.D. at 5
NS NS NS NS 2.02 1.18 NS NS
%
G1 18.2 21.4 22.0 20.5 28.44 30.47 36.57 31.83
G2 18.3 20.1 20.3 19.6 25.69 31.11 33.30 30.03
G3 17.9 21.0 21.6 20.2 24.47 29.89 35.04 29.80
S.Em.± 0.62 0.59 0.6 0.35 0.86 0.50 1.09 0.51
C.D. at 5
NS NS NS NS 2.48 1.45 NS 1.43
%
NV NS NS NS NS NS NS NS 1.98
NG NS NS NS NS NS 2.51 NS NS
VG NS NS NS NS 3.51 2.05 NS 2.04
NVG NS NS NS NS NS 3.55 NS NS
YNV NS NS
YNG NS NS
YVG NS NS
YNVG NS 6.04
CV% 12.8 11.85
392

393 Table 3. Effect of nitrogen and growth regulators on shoot:root ratio and LAI of cotton
394 genotypes.

Shoot: Root ratio LAI

Treatment 2019-20 2020-21 2021-22 Pooled 2019-20 2020-21 2021-22 Pooled
N1 4.05 5.10 5.97 5.04 5.42 5.68 5.86 5.65
N2 4.44 5.21 5.91 5.19 5.90 6.08 6.68 6.22
N3 3.60 5.19 5.45 4.74 6.26 6.04 7.23 6.51
S.Em.± 0.10 0.04 0.19 0.09 0.11 0.13 0.13 0.15
C.D. at 5
0.39 NS NS 0.28 0.47 NS 0.52 0.58
%
 V1 3.95 5.15 5.56 4.89 5.44 5.76 5.99 5.73
V2 4.11 5.18 6.00 5.09 6.28 6.11 7.20 6.53
S.Em.± 0.08 0.03 0.12 0.05 0.06 0.12 0.07 0.18
C.D. at 5
NS NS 0.34 0.14 0.18 0.35 0.19 NS
%
G1 4.23 5.18 6.11 5.17 5.97 5.85 6.73 6.19
G2 4.01 5.16 5.59 4.92 5.92 6.03 6.67 6.21
G3 3.85 5.15 5.63 4.87 5.70 5.91 6.37 5.99
S.Em.± 0.97 0.03 0.14 0.06 0.07 0.15 0.08 0.06
C.D. at 5
0.28 NS 0.41 0.17 0.22 NS 0.23 0.17
%
NV NS NS NS NS NS NS 0.33 0.25
NG NS NS 0.71 NS NS NS NS NS
VG NS NS NS NS NS NS NS NS
NVG NS NS NS 0.41 NS NS NS NS
YNV NS NS
YNG NS NS
YVG NS NS
YNVG NS NS
CV% 8.66 7.39
395

396 Table 4. Effect of nitrogen and growth regulators on Boll weight and number of bolls of cotton
397 genotypes.

Boll weight No of boll per sqm

2019- 2020- 2021- Poole
20 21 22 d 2019-20 2020-21 2021-22 Pooled
N1 3.03 2.51 2.84 2.80 122.6 215.0 150.8 162.8
N2 3.02 2.64 2.94 2.87 139.7 232.6 144.1 172.1
N3 3.08 2.66 2.92 2.89 143.8 223.0 164.6 177.1
S.Em.± 0.08 0.07 0.05 0.04 4.94 7.03 3.76 3.71
C.D. at 5
15.9 NS 14.7 11.1
% NS NS NS NS
V1 3.53 2.84 3.35 3.24 124.1 210.9 153.0 162.7
V2 2.56 2.37 2.46 2.46 146.6 236.1 153.3 178.7
S.Em.± 0.07 0.06 0.07 0.11 4.58 3.47 6.71 3.03
C.D. at 5
13.3 10.0 NS 8.53
% 0.19 0.17 0.20 0.67
G1 2.94 2.49 2.80 2.74 140.7 232.5 151.4 174.9
G2 3.12 2.64 3.06 2.94 126.5 224.4 148.8 166.6
G3 3.08 2.69 2.84 2.87 138.8 213.6 159.3 170.6
S.Em.± 0.08 0.07 0.08 0.05 5.61 4.25 8.22 3.66
 C.D. at 5
NS 12.3 NS NS
% NS NS NS 0.13
NV NS NS NS NS NS NS NS NS
NG NS NS NS NS NS 21.3 NS NS
VG NS 0.29 NS NS 23.0 17.4 NS NS
NVG NS NS NS NS NS 30.1 NS 25.7
YNV NS NS
YNG NS NS
YVG NS NS
YNVG NS NS
CV% 11.9 15.6
398

399

400 Figure 1. Effect of nitrogen and growth regulators on seed cotton yield.

401