Yield, system productivity and economics of foxtail millet-FCV tobacco cropping system as influenced by different nutrient management practices

Introduction

Agricultural sustainability is increasingly challenged by soil degradation, climate variability and rising input costs, necessitating efficient cropping systems and balanced nutrient management strategies. Mono-cropping of crops other than tobacco are not as remunerative as that of tobacco (Krishnareddy et al., 2007) [5] . Therefore, integrating short-duration nutri-cereals (millets) with high-value cash crops offers a viable approach to enhance system productivity and farm profitability. The foxtail millet (Setaria italica L.)-FCV tobacco (Nicotiana tabacum L.) cropping system holds considerable promise, particularly in the rainfed and Vertisol regions of Andhra Pradesh. Foxtail millet, a climate-resilient C₄ nutri-cereal with high nutritional value (Muthamilasaran and Prasad, 2021) [9] , efficiently utilizes kharif season resources, while FCV tobacco contributes substantial economic returns during rabi. Integrated nutrient management, combining inorganic fertilizers with organic sources such as farm yard manure, crop residue incorporation in-situ e.t.c., is essential to improve nutrient availability and restore soil fertility. Balanced nutrient management plays a critical role in influencing crop growth, yield, and quality in both component crops (Raviraja, 2020) [11] . Hence, the present study was conducted to assess the effect of different nutrient management practices on yield of foxtail millet and FCV tobacco and to workout the economics and system productivity in foxtail millet-FCV tobacco cropping system.

Materials and Methods

A field experiment was conducted during kharif (foxtail millet) and rabi (FCV tobacco) seasons of 2023-24 as a sequence at Black Soil Research Farm of ICAR -National Institute for Research on Commercial Agriculture (formerly CTRI), Rajahmundry, located at 17.04º N and 81.76º E at 14 m above mean sea level coming under the Godavari agro-climatic zone of Andhra Pradesh. The soil texture of the experimental field was clay (sand, silt and clay content in 0-15 cm soil layer was 25, 10, 65%, respectively), moderately alkaline in reaction (pH of 7.31), EC was non-saline (0.31 dS m -1 ), low in organic carbon (0.35%), low in available Nitrogen (185 kg ha -1 ), high in available Phosphorus (23 kg ha -1 ) and Potassium (445 kg ha -1 ). The experiment was carried out on permanent layout in randomised block design, with seven treatments viz., T 1: Absolute Control; T 2: 100% N through organic source, Farmyard manure (FYM); T 3 -25% N through organic + 75% N through inorganic; T 4 -50% N through organic + 50% N through inorganic; T 5 -75% N through organic +25% N through inorganic; T 6 -100% N through inorganic source (NPK); T 7 -Foxtail millet / tobacco crop residue incorporation using PUSA decomposer + RDF (Recommended dose of fertilizer) and replicated thrice. The RDF adopted for foxtail millet was 40 N (Urea): 20 P 2 O 5 (SSP): 20 K 2 O (SOP) kg ha -1 and for tobacco it is 50 N (Ammonium 50 P 2 O 5 (DAP): 50 K 2 O (SOP) kg ha -1 . The required quantity of 100%, 75%, 50% and 25% RDN through well decomposed FYM (0.5% N, 0.26% P and 0.5% K) was applied 15 days before sowing of the crop in respective plots and incorporated into soil after spreading uniformly as per the treatment. For kharif foxtail millet crop (i.e., start of the experiment) already field grown tobacco stalks from the research farm were collected and incorporated into T 7 plot (the incorporated dry matter of tobacco stalks was about 2.2 t ha -1 with N, P and K content of 1.6, 0.1 and 4.3%, respectively) whereas for rabi tobacco, the stover residue of kharif foxtail millet after harvest of the foxtail millet grain has incorporated in-situ in T 7 plot (the incorporated dry matter of foxtail millet stover was about 2.9 t ha -1 with N, P and K content of 1.17, 0.46 and 5.25% respectively) using PUSA decomposer (a fungal consortium developed by ICAR-Indian Agricultural Research Institute (IARI), Division of Microbiology, New Delhi) used for rapid degradation of agricultural residues, which are available in liquid/capsule/wettable powder forms. In this experiment wettable powder has been used and procured from IARI-New Delhi, Division of Microbiology. The cultivation practices for both kharif foxtail millet and rabi FCV tobacco are adopted as per package of practises except the inputs applied as treatments. The gross plot size and net plot size of foxtail was 6.3 m X 6.3 m and 5.4 m x 5.4 m, respectively and for tobacco it was 6.3 m x 6.3 m and 3.5 x 3.5 m, respectively. The cultivar used for foxtail millet is SiA-3088 (Suryanandi) and for FCV tobacco it is FCR-15 (Sreshta). Foxtail millet was sown with a spacing of 22.5 cm x 10 cm on last week of July-2023 and harvested on last week of October-2023, whereas for rabi FCV tobacco, sixty days old seedlings were transplanted on last week of November -2024 with a spacing of 70 cm x 70 cm. Tobacco leaves were harvested at maturity and flue cured. The data on foxtail millet grain yield, tobacco green and cured leaf yields and represented as kg ha -1 . Economics was calculated based on the prevailing market prices of the inputs and produce i.e., foxtail millet grain and tobacco cured leaf @ ₹ 45 kg -1 and ₹ 288.65 kg -1 , respectively. System productivity was calculated by adding foxtail millet grain yield with tobacco leaf yield in terms of tobacco leaf equivalent yield. The mean values were subjected to statistical analysis by adopting Fisher's method of analysis of variance for the design adopted in this study as outlined by Panse and Sukhatme, (1978) [10] .

Results and Discussion

Foxtail millet Grain and Stover Yield

Data on grain and stover yield of foxtail millet grain was presented in Table 1. The treatment involving crop residue incorporation with PUSA decomposer + RDF (T 7 ) recorded the significantly higher grain and stover yield (2095 and 2601 kg ha - 1 , respectively). While, treatments T 6 and T 3 exhibited statistically comparable yields. Conversely, the control plot registered the lower grain and stover yield (1039 and 1164 kg ha -1 respectively. The grain yield in T 7 was 12.98% higher than 100% N through inorganic source (T 6 ) and 50.4% higher than control. The higher grain and stover yield recorded under T 7 can be attributed to the synergistic effect of 100% RDF combined with crop residue incorporation using PUSA decomposer. This integration improved nutrient availability and uptake through enhanced root growth, while residue incorporation improved soil moisture retention, sustained nutrient release and more efficient partitioning and assimilation of metabolites. These conditions favoured efficient photosynthate accumulation and translocation during critical growth stages, leading to increased grain productivity. These findings were corroborated with the results of Meena et al. (2015) [7] and Aparna et al. (2019) [1] .

Economics

Significantly higher gross returns, net returns and B:C ratio (₹ 95,577 ha -1 , ₹ 69,080 ha -1 , 2.61, respectively) was realized from the treatment containing crop residue incorporation through PUSA decomposer + RDF. Nevertheless, T 6 and T 3 were on a par to each other. While the lower values of gross return, net returns and B:C ratio was recorded in control.

Tobacco Yield

Table 1 represents green leaf yield, cured leaf yield of FCV tobacco. Conjunctive application of crop residue incorporation through PUSA decomposer + RDF (T 7 ) recorded the higher green and cured leaf yields of 14210, 1953 kg ha -1 respectively. However, significantly lower green and cured leaf yield was recorded in control (T 1: 4487, 810 kg ha -1 , respectively). The increased green and cured leaf yields of tobacco under residue incorporation with a PUSA decomposer and RDF might be due to a balanced and sustained nitrogen supply, with fertilizers supporting early growth and residue mineralization meeting later crop demand. Improved microbial activity, soil structure, and nutrient use efficiency created a favourable rhizosphere, ultimately resulted in higher leaf yields. These findings align with earlier research by Kumaresan et al. (2003) [6] and Krishnareddy et al. (2007, 2009) [5,4] . the no fertilizer application i.e., control resulted in the lower yields due to insufficient native soil nutrients to support optimum plant growth

Economics

The higher gross returns, net returns and B:C ratio (₹ 5,63,733 ha -1 , ₹ 3,42,376 ha -1 and 1.55 respectively) were obtained with T 7 (Table 2) and it was on a par with 100% N through inorganics (NPK) (T 6 ). Crop residue incorporation through PUSA decomposer + RDF have improved the cured leaf yields leading to increase in gross returns and hence accrued higher net returns and B:C ratio. While the lower values of gross, net returns and B:C ratio was recorded in control (T 1 ). ₹ ha -1 System Productivity Among the different nutrient management practices evaluated, significantly higher tobacco leaf equivalent yield 2284 kg ha -1 was recorded with the conjunctive application of crop residue incorporation using microbial consortium + RDF (T 7 ) While control (T 1: 997 kg ha -1 ) recorded significantly lower tobacco leaf equivalent yield. The current results are in line with Mukesh Kumar, (2019) [8] and Kiran Kumar et al. (2020, 2022) [2,3] who reported that there was a significant improvement in system productivity due to inclusion of kharif crop before rabi tobacco in Vertisols of Andhra Pradesh and also residue in the cropping system.

Conclusion

It was concluded that combined application of crop residue incorporation using PUSA decomposer + RDF along with utilizing the resources effectively in pre-tobacco (kharif) crop season by introducing foxtail millet increases yield, overall system productivity, profitability of the cropping system.

References

1. Aparna K, Rekha B, Vani KP, Prakash TR. Growth and yield of finger millet as influenced by crop residue composting. J Pharmacogn Phytochem. 2019;8(4):11081111.
2. Kiran Kumar T, Damodar Reddy D, Chandrasekhararao C, Kasturikrishna S. Resource use efficiency and system productivity as influenced by crop intensification in FCV tobacco growing Vertisols of Andhra Pradesh. Tobacco Res. 2020;46(2):66-68.
3. Kiran Kumar T, Damodar Reddy D, Chandrasekhararao C, Kasturikrishna S, Srilakshmi P. Evaluation of crop diversification and intensification options for enhancing resource use efficiency, system productivity and farm income in FCV tobacco growing black soil region of Andhra Pradesh. Tobacco Res. 2022;48(2):71-73.
4. Krishnareddy SV, Kasturikrishna S, Kumar PH, Reddy PRS, Krishnamurthy V. Effect of rice (Oryza sativa) stubble and nitrogen on performance of tobacco (Nicotiana tabacum) in rice-tobacco cropping system. Indian J Agron. 2009;53(3):23-26.
5. Krishnareddy SV, Kasturi KS, Rao JAV, Kumar P, Krishnamurthy V. Effect of application of biofertilizers to soybean (Glycine max) and nitrogen to tobacco (Nicotiana tabacum) in soybean-tobacco cropping system. Indian J Agron. 2007;52(4):294-299.
6. Kumaresan K, Chandrasekhararao C, Athinarayan. Effect of different organic manures on the growth attributes, yield, quality and economics of chewing tobacco in Tamil Nadu. Tobacco Res. 2003;29(1):31-34.
7. Meena RK, Neupane MP, Singh SP. Effect of phosphorus levels and bio-organic sources on growth and yield of rice (Oryza sativa L.). Int J Agric Sci. 2015;2:286-289.
8. Mukesh Kumar P. Effect of nutrient and residue management practices on productivity, soil health and profitability of rice (Oryza sativa L.) -maize (Zea mays L.) cropping system. Ph.D Thesis. IGKV, Raipur; 2019.
9. Muthamilarasan M, Prasad M. Small millets for enduring food security amidst pandemics. Trends Plant Sci. 2021;26(1):33-40.
10. Panse VG, Sukhatme PV. Statistical methods for agricultural workers. ICAR, New Delhi; 1978. p. 145-150.
11. Raviraja SR, Balanagoudar MV, Ravi SN, Bhat, Yadahalli GS. Effect of integrated nutrient management practice on growth and yield of foxtail millet (Setaria italica L.) in black soil. Int J Curr Microbiol Appl Sci. 2020;9(3):21012108.