Cumulative impact of plant geometry and foliar spray of growth retardant on economics of cotton under high density planting system

Introduction

The production of fiber and oilseeds makes cotton the world's most important cash crop. (Dong et al., 2010) [5] . It is an important cash crop that is second only to food grains in terms of importance to the Indian economy. (Patel et al., 2016) [11] . Among cash crops, cotton is highly valuable and is known as the "King of Fiber Crops" in India. Global cotton production estimates for the 2022-2023 year, as reported by the US Department of Agriculture, point to a 35.5 million hectare cultivated area and 115.7 million bales produced (Anonymous, 2023a) [2] . With 13.0 million hectares under cultivation, India is notable for having the greatest cotton farming area during the same time period. The environment and methods of seasonal management have a big influence on cotton's growth and development (O' Berry et al., 2008) [9] . Maintaining a suitable plant population is one tactic to maximize output per unit area; this element differs throughout cotton cultivars (Ali et al., 2009) [1] . Appropriate plant spacing is essential for reaching the optimal plant density according to the variety's requirements, especially for increasing cotton yield. (Nadeem et al., 2010) [8] . Plants used in the High-Density Planting System (HDPS) must have a compact, determinate growth pattern with short fruiting branches and no vegetative branches on the main stem. (Venugopalan et al., 2013) [14] . The performance of the cotton crop under various spacing configurations must thus be carefully examined in order to understand the effects of plant density on crop development, seed production and quality (Basanagouda and Patil, 2007) [3] . Plant growth regulators or PGRs, are used to reduce negative effects and alter the architectural features of cotton plants (Echer and Rosolem, 2012) [6] . Plants with a shorter, more compact and open canopy as well as a higher ratio of vegetative to reproductive dry matter may be the outcome of applying plant growth regulators (Sawan, 2017) [13] . Therefore, the purpose of the study was to investigate how plant growth regulators and plant density affect cotton yield and economics.

Materials and Methods

The current study was conducted at the Regional Research Station, Anand Agricultural University, Anand (Gujarat), during the kharif seasons of 2022-2023 and 2023-2024. Three replications with a Randomized Block Design (Factorial) layout were used for the experiment. Three levels of plant growth regulators and four levels of plant geometry were used in twelve (12) treatment combinations. Thirty-six plots were comprised of twelve treatment combinations: P 1 -60 × 20 cm, P 2 -30-90-30 × 20 cm (paired row), P 3 -75 × 20 cm and P 4 -45-105-45 × 20 cm (paired row). Additionally, there were three treatments for plant growth regulators: G 1 -Control, G 2 -Chlormequat chloride 200 ppm at 60 and 75 DAS and G 3 -Paclobutrazol 23% SC at 60 and 75 DAS. Both years' experiments employed the GTHV 13/28 variety of cotton. Without altering the treatments' randomization, the experiment was carried out at the same location in both seasons. The soil in experimental field had loamy sand texture. The nutrients (NPK) application was done as per the recommended dose (240-00-00 kg NPK ha -1 ). The data on seed cotton were recorded in accordance with established protocols and Gomez and Gomez (1984) [7] analysis of variance technique for randomized block design (Factorial) design was used to conduct a statical analysis of the data relevant to seed cotton yield. A few formulas were employed to compute the economics, as explained below.

Gross return

Using the current local market pricing and the seed cotton yield from each treatment, the gross revenue, expressed in rupees per hectare, was computed.

Net returns

To calculate net returns, the whole cost of cultivation was deducted from each treatment's gross yields.

Benefit: cost ratio (B:C)

The benefit-cost ratio was determined by subtracting all costs from the total revenue from the total yield of seed cotton, accounting for the costs of all inputs required for different treatments as well as the current rates of the product market.

B:C ratio =

Gross returns (₹/ha) Total cost of cultivation (₹/ha)

Results and Discussion

The maximum economic return on a treatment determines how adaptable agronomic procedures are on a regional level for any given crop. Thus, for a reliable comparison of agronomic approaches and competent advice, the economics of various treatments must be determined. The current market price of seed cotton, together with several variable and non-variable inputs, were used to compute the cost of production, gross return, net return and BCR for various treatments. The plant geometry and plant growth regulators (average of both years) individual component yield and economics are shown in Table 1. Data presented in Table 1 clearly indicated that paired row spacing of 30-90-30 × 20 cm and application of chlormequat chloride 200 ppm at 60 and 75 DAS (P 2 G 2 ) recorded maximum seed cotton yield (3028 kg/ha), net return of ₹ 1,22,359 /ha with BCR 3.06 followed by P 1 G 2 (60 × 20 cm and application of chlormequat chloride 200 ppm at 60 and 75 DAS) seed cotton yield (2923 kg/ha), net return of ₹ 1,11,020 /ha with BCR 2.73 and P 2 G 3 (paired row spacing of 30-90-30 × 20 cm and application of paclabutrazole 23% SC at 60 and 75 DAS) seed cotton yield of 2693 kg/ha, net return of ₹ 1,01,437 /ha with BCR 2.69. The combination of paired row spacing and CCC application optimizes plant architecture and resource use, leading to higher boll numbers and larger boll size, thus increasing the overall yield, net return and benefit cost ratio. The narrower spacing of 90 × 30 cm resulted in significantly higher net return of ₹38,603 per hectare (Biradar et al. 2010) [4] . Reddy (2012) [12] reported that maximum net returns and returns per rupee of investment were achieved with higher planting density than other lower planting density. The gross monetary returns (₹ 124320/ha) and net monetary returns (₹ 85076/ha) were significantly the highest with 2.22 lakh plant population per hectare (Paslawar et al. 2015) [10] . While minimum seed cotton yield of 1715 kg/ha, net return of ₹ 43,582 /ha with 1.73 BCR was noticed with plant geometry P 3 (75 × 20 cm) with plant growth regulators G 1 (Control).

Conclusion

The study demonstrates that using a 30-90-30 × 20 cm paired row spacing with 200 ppm Chlormequat chloride greatly increases cotton yield, net return and benefit-cost ratio. The results indicate that integrating high-density planting with the proper application of PGRs, particularly CCC, can significantly improve cotton productivity and profitability, presenting an efficient agronomic strategy for maximizing yields.

References

1. Ali A, Tahir M, Ayub M, Ali I, Wasaya A, Ahmed KF. Studies on the effect of plant spacing on yield of recently approved cotton varieties. Pakistan Journal of Life and Social Sciences. 2009;7:25-30.
2. Anonymous. Area, production and productivity of cotton. Indiastat.com; 2023.
3. Basanagouda, Patil C. Performance of compact cotton genotypes (Gossypium hirsutum) at three spacing and two moisture levels. In: Proceedings of the World Cotton Research Conference-4; 2007 Sep 10-14; Lubbock. p. 1.
4. Biradar V, Rao S, Hosomani V. Economics of late sown Bt cotton (Gossypium hirsutum L.) as influenced by different plant spacing, fertilizer levels and NAA applications under irrigation. Indian Journal of Agricultural Science. 2010;6(1):196-198.
5. Dong H, Kong X, Li W, Tang W, Zhang D. Effects of plant density and nitrogen and potassium fertilization on cotton yield and uptake of major nutrients in two fields with varying fertility. Field Crops Research. 2010;119:106-113.
6. Echer FR, Rosolem CA. Plant growth regulator losses in cotton as affected by adjuvants and rain. Ciência Rural. 2012;42(12):2138-2144.
7. Gomez K, Gomez A. Statistical procedures for agricultural research. 2 nd ed. New York: John Wiley and Sons; 1984.
8. Nadeem MA, Ali A, Tahir M, Naeem M, Chadhar AR, Ahmad S. Effect of nitrogen levels and plant spacing on growth and yield of cotton. Pakistan Journal of Life and Social Sciences. 2010;8:121-124.
9. O'Berry NB, Faircloth JC, Edmisten KL, Collins GD, Stewart AM, Abaye AO, et al. Plant population and planting date effects on cotton (Gossypium hirsutum L.) growth and yield. Journal of Cotton Science. 2008;12:178-187.
10. Paslawar AN, Meena AK, Deotalu AS, Bhale VM, Ingole PG, Rathod TH. Foliar application of mepiquat chloride under high density planting system on different species of cotton. In: National Symposium on Future Technologies: Indian Cotton in the Next Decades; 2015; Acharya Nagarjuna University, Guntur. p. 39.
11. Patel P, Patel JC, Vyas KG, Salvi D. Effect of hybrids and varying planting time on growth and productivity in cotton (Gossypium hirsutum L.). The Bioscan. 2016;11(1):289-291.
12. Hyderabad: Acharya N.G. Ranga Agricultural University; 2012.
13. Sawan ZM. Plant density; plant growth retardants: its direct and residual effects on cotton yield and fiber properties. International Journal of Environmental Sciences and Natural Resources. 2017;5(3):555-663.
14. Venugopalan MV, Kranti KR, Blaise D, Lakde S, Sankaranarayana K. High-density planting system in cotton: the Brazil experience and initiations. Cotton Research Journal. 2013;5:172-185.