Weed dynamics and yield of single eye-budded settling sugarcane as influenced by spacing and weed management practices under south Gujarat conditions

Introduction

Sugarcane (Saccharum officinarum L.) is a crucial commercial and industrial crop grown in tropical and subtropical areas worldwide. In addition to being the main source of sugar, it is an essential raw material for producing jaggery, ethanol, biodegradable products, paper, and livestock feed, thus making a significant contribution to both agricultural and industrial economies (Mishra et al., 2021) [8] . India holds the second position in sugarcane production globally, following Brazil, with sugarcane cultivated across 55.07 lakh hectares, yielding 4399.30 lakh tonnes, achieving a productivity rate of approximately 80-90 t/ha, and a sugar recovery rate of 10.25% for the period of 2024-25 (Anonymous, 2025) [1] . In Gujarat, sugarcane occupies 1.89 lakh hectares with a production of 137.11 lakh tonnes and productivity of 71.60 t/ha, contributing substantially to the state's agricultural economy (Anonymous, 2025) [1] . Major sugarcane-growing districts of Gujarat include Junagadh, Vadodara, Narmada, Bharuch, Tapi, Surat, Navsari, and Valsad. Among the numerous factors that hinder sugarcane productivity, weed infestation stands out as one of the most significant biotic challenges. Weeds compete with the sugarcane for essential resources such as nutrients, moisture, light, and space, leading to suboptimal crop growth and considerable yield reductions. The intensity of weed competition varies with the growth stage of the crop, being especially critical during the initial growth phase. Research indicates that the critical period for crop-weed competition in sugarcane lasts from 60 to 120 days after planting (DAP) for spring-planted cane and can extend up to 150 DAP for autumn-planted cane (Rohitashav et al., 2011) [13] . Yield losses attributed to unchecked weed proliferation can range from 40 to 67 percent, particularly in regions where advanced weed management practices are not sufficiently implemented (Srivastava and Chauhan, 2006) [15] . Effective management of weeds necessitates an understanding of weed species, critical periods of competition, and appropriate control strategies. Implementing timely weed control during these critical periods reduces competition between crops and weeds, thereby promoting crop growth and productivity (Suganthi et al., 2019) [17] . In sugarcane cultivation, weed management can be accomplished through various methods, including manual, mechanical, biological, and chemical approaches. While manual weeding is effective, it tends to be labor-intensive, timeconsuming, and expensive. Mechanical methods may occasionally result in damage to the crop, while herbicides present a more cost-effective and efficient alternative, especially in situations where labor is limited. Consequently, integrated weed management strategies that combine cultural, mechanical, and chemical methods are increasingly advocated for the sustainable production of sugarcane. Sugarcane serves as a significant cash crop in South Gujarat, with many farmers relying on it for their income and livelihood. Thus, enhancing productivity and profitability through efficient agronomic methods is crucial. Among these methods, effective weed management is essential for decreasing yield losses, reducing weed infestation, and lowering cultivation costs. In light of these factors, the current study was conducted to identify effective weed management strategies for single-eye budded settling planted sugarcane in the context of South Gujarat conditions.

Materials and Methods

A field experiment was carried out at College Farm, N. M. College of Agriculture, Navsari Agricultural University, Navsari, Gujarat, India during rabi season of two consecutive years 2023-24 and 2024-25. Geographically, site is situated at 20˚ 57' North latitude, 72˚ 54' East longitude with an elevation of 10 meters of above the mean sea level. Experiment was laid out in Split Plot Design with four spacings as main plot and seven weed control measures as sub plots (Table 1). Settlings were grown using the single eye buds of sugarcane variety CoN 15071(Divyashi). After 25 days of sowing, emerged settlings were transplanted to the main field. Recommended dose of fertilizers (250 -125 -125 kg N-P 2 O 5 -K 2 O/ha) was given in the form of urea, single super phosphate and muriate of potash. Weed management was done by hand weeding, intercropping and applying herbicides as per treatments, except in the unweeded control plot. Additionally, final earthing up was carried out at 135 to 140 days after transplanting of crop. In W 4 , dhaincha was cut down at 55 DAS and kept as mulch in the same place for smothering the weeds and incorporated in the soil at final earthing up. Observations were recorded on weed population, dry weight of weeds, weed control efficiency, weed index and cane yield at harvest. Recorded data was subjected to statistical analysis of variance as per procedure of Split Plot Design as described by Panse and Sukhatme (1967) [10] . For weed population studies at 60 and 90 days after transplanting for monocots and dicots, the data were first transformed to square root to reduce the range of variation and then statistically analysed by standard method as described by Steel and Torrie (1960) [16] .

Results and Discussion

Weed Population at 60 DAP Different spacing treatments were not significantly affected the weed population at 60 DAP (Table 2). The lowest monocot (11.13/m 2 ), dicot (8.08/m 2 ), sedges (12.26/m 2 ) and total weed population (32.08/m 2 ) was observed under W 2 (Hand weeding at interval of 30 days up to 150 DAP) and was at par with W 3 (IC fb HW at 30 and 60 DAP). This was followed by W 5 , W 6 and W 7 being on par with each other. Significantly higher weed infestation was observed under W 1 (untreated control), with pooled data of monocots (25.20/m 2 ), dicots (18.54/m 2 ), sedges (28.26/m 2 ) and total weeds (72/m 2 ).

Weed Population at 90 DAP

Weed population at 90 DAP was not significantly varied among different spacing treatments during both the years (Table 3). Among weed management practices, W 2 recorded the lowest monocots (11.35, 10.85 and 11.10/m 2 during both the years and in pooled analysis, respectively) and dicot weed population (8.11, 8.09 and 8.10/m 2 during both the years and in pooled analysis, respectively) and was at par with W 3 with monocots (12.80, 12.45 and 12.65 during both the years and in pooled analysis, respectively) and dicots (9.11, 9.39 and 9.25/m 2 during both the years and in pooled analysis, respectively). This was followed by W 5 and at par with W 6 .

In case of sedges weeds, lower weed population was recorded with W 5: HW fb 2,4-D@ 1.5 kg/ha + Metribuzine @1.0 kg/ha (7.49, 6.46 and 6.98/m 2 during both years and pooled analysis, respectively) and was at par with W 6: HW fb Readymix-Sulfentrazone 28% + Clomazone 30% wp @ 700 + 750 g/ha (7.91, 6.89 and 7.40/m 2 during both years and pooled analysis, respectively). This was followed by W 7 and W 2 . At 90 DAP, total weed population was significantly recorded lower in case of W 2: weed free (31.21, 29.40 and 30.30/m 2 during both the years and in pooled analysis, respectively) it was statistically comparable with W 5: HW fb 2,4-D@ 1.5 kg/ha + Metribuzine @1.0 kg/ha (33.05, 31.86 and 32.46/m 2 during both the years and in pooled analysis, respectively) and W 6: HW fb Readymix-Sulfentrazone 28% + Clomazone 30% wp @ 700 + 750 g/ha (33.71, 32.89 and 33.30/m 2 during both the years and in pooled analysis, respectively) Followed by lower total weed population was observed in W 3 at par with W 7 .

Weed Dry Weight at 90 DAP and Final Earthing up (g/m 2 )

Weed dry weight at 90 DAP and Final earthing up was not significantly varied with different spacing treatments (Table 4&5). Among weed management treatments, W 2 (weed free) recorded the lowest weed dry weight in both years (18.84 In the study, weed-free treatment consistently recorded the lowest weed population, dry weight and higher weed control efficiency, indicating complete suppression of crop-weed competition.

However, comparable performance of W 3 (intercultivation followed by hand weeding) and integrated treatments W 5 (HW + 2,4-D + metribuzin), W 6 (HW + mesotrione + atrazine) and W 7 (HW + sulfentrazone + clomazone) suggests that combining mechanical weeding with post-emergence herbicides provides extended weed control by targeting both initial and subsequent weed flushes, ensuring season-long weed control. These weed control results alingn with previous studies of Singh and Kumar (2013) [14] , Ombase et al. (2019) [9] , Kadam et al. (2023) [7] , Patel et al. (2024) [11] and Jaiswal et al. (2024) [6] . In contrast, unweeded check produced high weed population, dry weight due to no weed control and led to higher yield losses as confirmed with higher weed index.

Cane yield (t/ha) Among the spacings, S [4] , Chaudhari et al.

(2021) [3] and Virdia et al. (2023) [18] where it was observed that wider inter row and closer intra row spacing increased plant density and yield due to better canopy architecture and resource utilization. The lowest yield recorded under the 120 × 60 cm spacing (S 4 ) suggested that excessively intra row spacing reduced effective stand and light interception, leading to lower productivity (Table 7).

Weed management significantly influenced sugarcane yield. The weed free treatment (W 2 ) maintained by hand weeding at 30 day intervals up to 150 DAP produced the highest pooled cane yield (111.76, 112.52 and 112.14 t/ha during both years and pooled data, respectively) which was statistically at par with W 3: Interculturing followed by hand weeding at 30 and 60 DAP (109.72, 111.17 and 110.45 t/ha) and W 5: Hand weeding at 30 DAP + application of 2,4-D@ 1.5kg/ha + Metribuzine @1.0 kg/ha (Post emergence) at 60 DAP (107.5, 108.2 and 107.91 t/ha). In contrast, significantly lower cane yield was recorded under unweeded control (50.56, 52.11 and 51.33 t/ha). The yield advantage under intercultivation + hand weeding (W 3 ) and hand weeding fb 2,4-D@ 1.5kg/ha + Metribuzine @1.0 kg/ha as 60 DAP provided effective weed control as weed-free which assisted in expression of full plant potential to gain higher cane yield production. This is consistent with literature, Ballyan et al.

(2015) [2] , Ramesha et al. (2018) [12] , Ghodke et al. (2020) [5] and Patel et al. (2024) [11] where effective weed management through cultural and chemical methods has been reported to minimize weed biomass and improve cane yield significantly.

Conclusion

Based on the results of the experiment under South Gujarat conditions, planting sugarcane at 150 × 30 cm spacing coupled with interculturing followed by hand weeding at 30 and 60 DAP (W₃) or hand weeding at 30 DAP followed by application of 2,4-D @ 1.5 kg/ha+ metribuzin @ 1.0 kg/ha at 60 DAP (W₅) can be recommended as effective and economically feasible weed management practices for achieving higher cane yield and efficient weed control in single-eye budded settling planted sugarcane.

References

1. Anonymous. Annual report 2024-2025. Sugarcane Breeding Institute; 2025. p. 78-99.
2. Ballyan V, Kumar S, Kumar N, Kumar S. Weed management in spring-planted sugarcane. Indian Journal of Weed Science. 2015;47(1):46-49.
3. Chaudhari VD, Virdia H, Chaudhari NR. Sugarcane (Saccharum officinarum L.) yield and quality in relation to planting methods, spacing and intercropping. International Journal of Farm Science. 2021;11(4):109-113.
4. Ghaffar A, Akbar N, Khan SH, Jabran K, Hashmi RQ, Iqbal A, et al. Effect of trench spacing and micronutrients on growth and yield of sugarcane (Saccharum officinarum L.). Australian Journal of Crop Science. 2012;6(1):1-9.
5. Ghodke SK, Chaudhari PM, Thorave DS. Integrated weed management in preseasonal sugarcane. International Journal of Current Science. 2020;8(4):3183-3187.
6. Jaiswal VP, Shukla SK, Sharma L, Singh VP, Gaur A, Jha A, et al. Integrated use of 2,4-D, metribuzin, and pyrazosulfuron-ethyl (UPH 114b) for managing weeds and improving sugarcane yield in subtropical India. Sugar Technology. 2024;26(6):1626-1639.
7. Kadam TS, Bholane JP, Sapkal PD. Effect of weed management practices on weed indices, growth, yield attributes and quality in Suru sugarcane. The Pharma Innovation Journal. 2023;12(12):1531-1535.
8. Mishra P, Al Khatib AMG, Kumar SI, Mohammed J, Karakaya K, Dash A. Modeling and forecasting of sugarcane production in India. Sugar Tech. 2021;23(6):1317-1324.
9. Ombase KC, Chaudhari PM, Ghodke SK, Dixit RM. Effect of weed management practices on weed dynamics, growth, yield and economics of spring sugarcane (Saccharum officinarum L.). International Journal of Chemical Studies. 2019;7(5):2555-2557.
10. Panse VG, Sukhatme PV. Statistical methods for agricultural workers. 2nd ed. New Delhi: Indian Council of Agricultural Research; 1967.
11. Patel T, Dudhat MS, Patel D, Thanki JD. Comparative evaluation of agronomical, mechanical and chemical management of weeds and their impact on sugarcane productivity. Indian Journal of Weed Science. 2024;56(2):167-175.
12. Ramesha YM, Bhanuvally M, Krishnamurthy D, Gaddi AK. Weed management effect on growth and yield of sugarcane. Indian Journal of Weed Science. 2018;50(4):373-376.
13. Rohitashav S, Shyam R, Bhatnagar A, Singh VK, Kumar J. Bio-efficacy of herbicides applied at the 2 to 4 leaf stage of weeds in sugarcane after second interculture. Indian Journal of Weed Science. 2011;43(3-4):145-148.
14. Singh J, Kumar R. Management of weeds for sustainable sugarcane production in subtropical India. Indian Journal of Sugarcane Technology. 2013;28(2):95-99.
15. Srivastava TK, Chauhan RS. Weed dynamics and control of weeds in relation to management practices under sugarcane (Saccharum species complex hybrid) multi-ratooning system. Indian Journal of Agronomy. 2006;51(3):228-231.
16. Steel RGD, Torrie JH. Principles and procedures of statistics: with special reference to the biological sciences. New York: McGraw-Hill; 1960.
17. Suganthi M, Muthukrishnan P, Chinnusamy C. Crop weed competition in sugarcane: a review. Agricultural Reviews. 2019;40(3):239-242.
18. Virdia H, Patel V, Patel J. Effect of planting geometry for single eye budded settling on growth, yield and quality of sugarcane under South Gujarat condition. Journal of Sugarcane Research. 2023;12(2):192-199.