Comparative analysis of broadleaf herbicides for optimizing growth of wheat (Triticum aestivum L.)

Introduction

Wheat (Triticum aestivum L.) is one of the most important staple food crops in India and across the globe, providing nearly 20% of the total dietary calories and proteins consumed worldwide (FAO, 2022) [1] . In India, wheat is cultivated across 30 million hectares, contributing over 100 million tonnes to the country's food grain basket annually (Ministry of Agriculture & Farmers Welfare, 2023) [3] . However, weed infestation remains one of the most significant constraints to wheat production, often causing yield reductions of 25-50% in unweeded conditions (Jat et al., 2013) [2] . Broad-leaved weeds such as Chenopodium album, Melilotus indica, Parthenium hysterophorus and Anagallis arvensis compete aggressively with wheat for nutrients, light, and moisture, particularly during the early crop growth stages. Manual weeding is labor-intensive and often impractical for large-scale operations, hence the use of selective herbicides is considered a viable and efficient alternative for integrated weed management in wheat ecosystems. Recent advances in chemical weed control have led to the evaluation and recommendation of several herbicides such as Carfentrazone-ethyl, Metsulfuron-methyl, and Florasulam for effective post-emergence management of broad-leaved weeds. Studies by Verma et al. (2023) [6] and Sharma et al. (2024) [4] demonstrated that Carfentrazone at 40 g a.i./ha significantly improved plant population and biomass accumulation in wheat fields by effectively suppressing broad-leaved weeds without harming the crop. Similarly, Metsulfuron-Methyl at 4-6g a.i./ha has been reported to provide good weed control while being safe for crop and soil, with minimal residue levels (Sondhia, 2008) [5] . However, performance of these herbicides may vary under different agro-climatic conditions and application doses. Hence, the present investigation was carried out to study the comparative efficacy of these herbicides on growth attributes, weed suppression and yield in wheat under the eastern Uttar Pradesh conditions.

Materials and Methods

Location and Climate

The experiment was conducted at (Pili Kothi) Agronomy Research Farm, T. Weed-free -T12

Experimental Design and Treatments

The experiment was laid out in a Randomized Block Design with twelve treatments and three replications:

Crop and Agronomic Details

The wheat variety used in the experiment was DBW-17. Recommended doses of fertilizers (120:60:40 N:P:K kg/ha) were applied. Sowing was done in the third week of November at 22.5 cm row spacing. Herbicides were applied 32 DAS using a sprayer.

Results and Discussion 1. Plant population per Square Meter

The results presented in Table 1 reveal that Carfentrazone at 40 g a.i./ha (T4) was the most effective treatment in maintaining higher wheat plant population at 120 DAS, recording 296 and 292 plants/m² during 2021-22 and 2022-23, respectively. Carfentrazone at 30 g a.i./ha (T3) also performed well with 278 and 274 plants/m². Metsulfuron Methyl at 6g a.i./ha (T10) maintained 284 and 282 plants/m², making it the best among the Metsulfuron treatments. Moderate plant populations were observed under 2,4-D 600 g a.e./ha (T1) and Carfentrazone at 20 g a.i./ha (T2). Lower doses of Florasulam (T5 and T6) significantly reduced plant density, while higher doses (T7 and T8) showed slight improvement but remained less effective. The Weed Free plot (T11) recorded the highest plant population, while the Weedy Check (T12) recorded the lowest (217 and 215 plants/m²). Overall, Carfentrazone at 40 g a.i./ha (T4) and Metsulfuron Methyl at 6g a.i./ha (T10) showed superior efficacy in maintaining optimum plant stands.

Conclusion

The field experiment conducted during Rabi 2021-22 and 2022-23 at Pili Kothi Agronomy Research Farm demonstrated that effective weed management significantly improves the growth and yield-related parameters of wheat. Among all treatments, Carfentrazone at 40 g a.i./ha and the Weed Free control consistently recorded superior performance in plant population, height, dry matter accumulation and leaf area index. Metsulfuron Methyl at 6g a.i./ha also showed promising results, ranking just below Carfentrazone in effectiveness. In contrast, Florasulam at lower doses and the Weedy Check treatment resulted in poor crop performance due to insufficient weed suppression. These findings underscore the importance of timely and efficient herbicide application to ensure robust wheat crop development and optimum productivity under subtropical conditions.

References

1. Food and Agriculture Organization of the United Nations. World food and agriculture -Statistical yearbook 2022. FAO; 2022.
2. Jat RA, Singh RG, Gill G. Weed management in wheat using new herbicide molecules -A review. Indian J Agron. 2013;58(3):373-9.
3. Ministry of Agriculture & Farmers Welfare. Agricultural Statistics at a Glance 2023. 2023.
4. Sharma K, Kumar S, Manuja S, Kumar M, Shivalika. Efficacy of carfentrazone-ethyl for managing broad-leaved weeds in wheat. Himachal J Agric Res. 2024;50(2):220-3.
5. Sondhia S. Persistence of metsulfuron-methyl in wheat crop and soil. Bull Environ Contam Toxicol. 2008;83(6):799802.
6. Verma B, Sahu V, Kewat ML, Singh R, Jha AK, Sahu MP. Effect of carfentrazone-ethyl on weed flora, growth and productivity in wheat. Pharma Innov J. 2023;12(3):36213624.