Effect of different NPK levels on Growth, yield and nutrient uptake of brown top millet (Urochloa ramosa L.) under rainfed conditions of Coimbatore

Introduction

Millets have made their comeback as crops of global importance in the view of climate change, nutritional insecurity and sustainable agricultural systems. They are suited to grow in marginal soils and rainfed environments, capable to withstand high temperature, low fertility and moisture stress and so they are considered as climate-resilient crops. With an annual yield of about 30 million tons, millets are produced on 30-32 million hectares worldwide, improving food security in Asia and Africa (FAO, 2023) [3] . Brown top millet (Urochloa ramosa L.), commonly known as Dixie signal grass, belongs to the family Poaceae is one of the small millets. The crop is vernacularly called 'Kula samai' in Tamil, 'Korale' in Kannada and 'Andu korra' in Telugu. The plant can be grown as a contingency crop under rainfed conditions because it completes its life cycle within 75 to 90 days (Pavankumar et al., 2021). [8] The distribution of brown top millet in India includes the states of Karnataka, Andhra Pradesh, Telangana, Tamil Nadu and Chhattisgarh and extends to certain regions in Africa and Southeast Asia (Singh et al., 2022) [11] . Brown top millet has high dietary fibre content (12.43 g/100 g). It also contains minerals such as calcium (26.24 mg/100 g), iron (6.98 mg/100 g), zinc 2.88 mg/100 g), copper (1.43 mg/100 g), manganese (0.88 mg/100 g) and protein content (13.37 g/100 g) (Harichandana et al., 2023) [5] . The crop contains antioxidants and bioactive compounds which make it suitable for people who have gluten intolerance and metabolic disorders like hyperglycaemia. It also controls blood sugar levels, enhances cardiac health, reduces constipation, aids digestion and promotes bone health. [13] . Under rainfed agro-ecological conditions prevailing in Coimbatore region, lack of region-specific fertilizer recommendation often limits crop performance; hence the present study was undertaken to evaluate the effect of NPK levels on growth, yield and nutrient uptake of brown top millet. ) variety IIMR AK-2 was sown at 30×10 cm spacing using a seed rate of 3 kg/ha, with a gross plot size of 5.4 m×4.0 m and net plot size of 3.5 m×3.2 m. Nitrogen (Neem coated Urea) was applied in two equal splits, 50% basal and the remaining 50% top-dressed at 30 days after sowing. Basal doses of Phosphorus (Single super phosphate) and Potassium (Muriate of potash) were applied during the time of sowing. Before sowing, a tank mix solution containing chlorpyriphos (0.05%) was sprayed to control termite infestation. The experimental data were statistically analyzed using the analysis of variance (ANOVA) (Gomez and Gomez, 1984), [4] and significance was tested at 5% level of probability.

Materials and Methods

Results and Discussion

Effect of various nutrient levels on Growth and Yield of Brown top Millet

Plant height of brown top millet was significantly influenced by different fertilizer levels (Table 1). Among the treatments, application of 60:30:20 kg N:P₂O₅:K₂O/ha recorded the higher plant height (118.27 cm), followed by the treatment with the application of 60:30:10 kg N:P₂O₅:K₂O/ha (T₁₂) (115.90 cm). The lower plant height (86.62 cm) was observed in the treatment with the application of 20:10:10 kg N:P₂O₅:K₂O/ha. The increase in plant height under higher fertilizer levels may be attributed to the balanced supply of essential nutrients, which improved nutrient availability and enhanced vegetative growth. These are consistent with the findings of Thakur et al., (2019) [13] .

The dry matter production of brown top millet showed a significant response to different nutrient level treatments according to the results shown in Table 1. The treatment with application of 60:30:20 kg N:P₂O₅:K₂O/ha produced higher dry matter of 6436 kg/ha followed with the application of 60:30:10 kg N:P₂O₅:K₂O/ha which produced dry matter of 6341 kg/ha. The treatment 20:10:20 kg N:P₂O₅:K₂O/ha produced the least amount of dry matter which resulted in dry matter production of 4795 kg/ha. The increased fertilizer application led to higher dry matter growth where it resulted in better nutrient access for plants to produce more biomass (Pavankumar et al., 2021) [8] . Grain yield of brown top millet was substantially influenced by different nutritional levels (Table 1). The higher grain yield of 1185 kg/ha was recorded with the application of 60:30:20 kg N:P₂O₅:K₂O/ha, followed by the treatment with the application of 60:30:10 kg N:P₂O₅:K₂O/ha (1156.91 kg/ha). The lower grain yields were recorded in 20:10:10 kg N:P₂O₅:K₂O/ha (723.22 kg/ha). Improved nutrient availability could have boosted crop development and enabled effective assimilate partitioning which may be the cause of the higher grain production under higher fertilizer levels. Additionally, Siddiqui et al., (2020) [10] reported that balanced nutrient administration increased grain yield of brown top millet. Straw yield of brown top millet differed significantly among the nutrient treatments (Table 1). The higher straw yield of 2488.50 kg/ha was recorded in the treatment with the application of 60:30:20 kg N:P₂O₅:K₂O/ha, which was on par with 60:30:10 kg N:P₂O₅:K₂O/ha (2429.45 kg/ha). The lower straw yield was recorded in the treatment with the application of 20:10:10 kg N:P₂O₅:K₂O/ha (1569.3 kg/ha). Increased straw yield under higher fertilizer levels reflects greater vegetative growth and biomass accumulation under adequate nutrient supply (Anitha et al., 2020) [2] .

Effect of various nutrient levels on Net returns and Benefit-Cost ratio of Brown top Millet

Net returns and benefit-cost ratio of brown top millet were also influenced by nutrient levels (Table 1). The higher net return (₹8,945.20) was obtained with the application of 60:30:10 kg N:P₂O₅:K₂O/ha, which remained statistically comparable with 60:20:20 kg N:P₂O₅:K₂O/ha (₹8,606.50).

The minimum net returns (₹1,639.12) were observed in 20:10:20 kg N:P₂O₅:K₂O/ha. The higher benefit-cost ratio (1.35) was recorded with 60:30:10 kg N:P₂O₅:K₂O/ha and 60:20:10 kg N:P 2 O 5 :K 2 O/ha, whereas the lower B:C ratio (1.08) was noted under 20:10:20 kg N:P₂O₅:K₂O/ha. According to Triveni et al., (2023) [14] , there exist a connection between increased fertilizer use and improved crop productivity, which resulted in higher profitability and greater economic returns for farmers.

Effect of various nutrient levels on Nutrient uptake of Brown top Millet

Uptake of nitrogen, phosphorus and potassium by brown top millet differed significantly by nutrient dosage (Table 1). The maximum nutrient uptake was obtained in the treatment with the application of 60:30:20 kg N:P₂O₅:K₂O/ha (52.07 kg/ha N, 16.81 kg/ha P₂O₅, 58.69 kg/ha K₂O). The minimum nutrient uptake was observed in the treatment with the application of 40:20:0 kg N:P₂O₅:K₂O/ha (24.34 kg/ha N, 6.77 kg/ha P₂O₅, 26.86 kg/ha K₂O). Higher nutrient absorption at higher fertilizer doses reflects [12] .

Conclusion

The results of the current study indicated that balanced fertilization had a significant influence on the growth, yield and nutrient dynamics of brown top millet. Among the treatments evaluated, application of 60:30:20 kg N:P₂O₅:K₂O/ha produced comparatively higher grain yield, straw yield with greater nutrient uptake. Brown top millet is generally cultivated with limited nutrient management and farmers are less aware about its fertilizer requirement, thus identifying an optimum dose is important. Based on the results, the application of 60:30:20 kg N:P₂O₅:K₂O/ha will be suitable for improving productivity of brown top millet under rainfed conditions of Coimbatore.

Acknowledgement

AcknowledgementsThe authors express their deepest appreciation to the Chairperson, Advisory Committee members and Dean of Karunya Institute of Technology and Sciences, Coimbatore for their essential support during the entire research process. The authors also gratefully acknowledge the university for providing the necessary facilities for laboratory analysis which supported the successful completion of this research.

References

1. Abhigna D, Kalpana R, Janaki P, Geetha P, Radhamani S, Ravichandran V. Influence of various establishment techniques, spacings and fertilizer levels on leaf traits, yield and nutrient dynamics of brown top millet (Brachiaria ramosa L.) under different cropping seasons of Tamil Nadu. Plant Sci Today. 2023;10(4):654-664.
2. Anitha KV, Chikkaramappa T, Basavaraja PK, Prakash NB, Murali K, Boraiah B. Effect of different levels of fertilizers on productivity and nutrient dynamics of brown top millet. Int Res J Pure Appl Chem. 2020;21(24):308-320.
3. FAO. FAOSTAT statistical database [Internet]. Rome: Food and Agriculture Organization of the United Nations; 2023 [cited 2026 Jan 15]. Available from: https://www.fao.org/faostat/
4. Gomez KA, Gomez AA. Statistical procedures for agricultural research. 2nd ed. New York: John Wiley and Sons; 1984. p. 680.
5. Harichandana P, Karakannavar S, Sreeramaiah H. The nutritional composition of brown top millet. Pharma Innov J. 2023;12(8):1861-1864.
6. Kaushik A, Saxena DC, Singh S. Functional, thermal, pasting, and antioxidant properties of flour from Indian brown top millet (Brachiaria ramosa) cultivars. Food Biophys. 2024;19:637-652.
7. Nandini C, Joshi DC, Maharajan T. Reviving the abandoned brown top millet (Urochloa ramosa L.) for sustainable future food systems: current knowledge and emerging paradigms. Plant Breed. 2026;145(1):1-23.
8. Pavankumar N, Hemalatha S, Subramanyam D, Kumar AR, Sagar GK. Effect of plant geometry and nitrogen levels on growth and yield of brown top millet (Brachiaria ramosa L.) under southern agro-climatic zone of Andhra Pradesh. Pharma Innov J. 2021;10(12):207-211.
9. Sai Kishore A, Bhanu Rekha K, Hussain SA, Madhavi A. Growth, yield and nutrient uptake of brown top millet (Brachiaria ramosa) under varying sowing dates and nitrogen levels. Indian J Agron. 2024;69(1):95-98.
10. Siddiqui DA, Sharma GK, Chandrakar T, Thakur AK, Pradhan A. Differential levels of fertilizer and row spacing affect growth and yield of brown top millet (Brachiaria ramosa L.) in Entisols of Bastar plateau zone of Chhattisgarh. Int J Curr Microbiol Appl Sci. 2020;9(8):3459-3472.
11. Singh S, Suri S, Singh R. Potential and unrealized future possibilities of brown top millet in the food sector. Front Sustain Food Syst. 2022;6:974126. doi:10.3389/fsufs.2022.974126.
12. Sukanya TS, Nagaraja TE, Kiran HP, Anand MR, Chaithra C, Latha HS. Studies on nutrient management in nutricereal-brown top millet. Biol Forum Int J. 2021;13(4):952-956.
13. Thakur AK, Kumar P, Netam PS. Effect of different nitrogen levels and plant geometry on yield and nutrient uptake by brown top millet (Brachiaria ramosa L.). Int J Curr Microbiol Appl Sci. 2019;8(3):223-229.
14. Triveni U, Nagarjuna D, Jogarao P, Rani YS, Anuradha M, Patro TSSK. Influence of fertilizer nutrition and row spacing on productivity and profitability of brown top millet (Brachiaria ramosa L.). Andhra Agric J. 2023;70(3):288-295.