Impact of conservation tillage on soil fertility, and yield of soybean in soybean-chickpea sequence in vertisols

Introduction

Soybean (Glycine max L.) is an important oilseed and food-feed crop cultivated worldwide. It occupies more than 140 million ha globally, with production exceeding 390 million tonnes. Brazil, the USA, Argentina, China, and India are the major soybean-producing countries (FAOSTAT, 2024). In India, soybean is predominantly grown during the Kharif season under rainfed conditions. During 2024-25, soybean was cultivated on 126.90 lakh ha, with Maharashtra accounting for 50.72 lakh ha, of which 19.21 lakh ha was under the Vidarbha region. The average soybean productivity in Maharashtra was 1170.13 kg ha⁻¹ (Anonymous, 2025). However, productivity remains affected by variable weather conditions and inadequate agronomic practices, emphasizing the need for improved management strategies. Conservation agriculture (CA) is a sustainable production approach based on minimum soil disturbance, permanent soil cover, and crop diversification. Reduced and zero tillage, along with crop-residue retention, can improve soil physical, chemical, and biological properties, enhance water and nutrient-use efficiency, reduce erosion and production costs, and sustain crop productivity (Lal, 2015; FAO, 2016). Long-term intensive cultivation and excessive soil disturbance can degrade soil quality by accelerating organic matter decomposition and reducing soil health. In contrast, conservation tillage helps maintain soil organic matter, improve soil structure and biological activity, and enhance long-term soil fertility and productivity [7,8,15] . Therefore, evaluating suitable conservation tillage practices under soybean-chickpea cropping systems on Vertisols is essential for improving soil fertility, nutrient uptake, and soybean productivity. The present study was undertaken to assess the effect of conservation tillage on soil fertility, soil biological properties, yield, and nutrient uptake of soybean in a soybean-chickpea sequence on Vertisols, and to examine the relationship between soil properties and soybean yield.

Materials and methods

The study was conducted to assess the impact of conservation tillage on soil fertility and yield of soybean in a soybean-chickpea sequence in Vertisols. The field experiment commenced in 2017-18, and the present study was carried out during 2025-26 on the research farm of the Dryland Agriculture Unit, Dr. PDKV, Akola, Maharashtra. The Vertisols of the experimental site were fine, smectitic, hyperthermic family of Typic Haplusterts. Experimental soil was nearly neutral to slightly alkaline in nature pH 7.69, with organic carbon (0.53g kg -1 ) and electrical conductivity (0.30 dSm -1 ); available nitrogen (175.4 kg ha -1 ) was low, available phosphorus was low (17.9 kg ha -1 ), available potassium (291.6 kg ha -1 ) was high, and the soil was sufficient in available micronutrients. This experiment was laid out in a randomized block design with five treatments and four replications at the research farm of the Dryland Agriculture Unit, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola, Maharashtra. The different treatments were Conventional tillage (CT) -Ploughing once in 3 years + 2 presowing harrowings + One hand weeding + Opening of furrow with hoe in each row at 30-35 DAS + Crop residue mulch (T1), Conventional tillage (CT) -Ploughing once in 3 years + 2 presowing harrowings + One hand weeding + Opening of furrow with hoe in each row at 30-35 DAS without crop residue mulch(T2), Reduced tillage (RT) -Broad bed and furrow every year+ Pre and post emergence herbicideapplication + crop residue mulch (T3), Zero tillage + crop residue mulch(T4), Permanent BBF with furrow after every 4 rows + crop residue mulch(T5). The soybean variety JS-9305 was sown in the present investigation. The recommended dose of fertilizers 30: 60: 30 N:P2O5:K2O kg ha -1 was used. After harvest of the crop, representative soil samples (0-20 cm) wascollected from all the plots.Plot-wiseseed and straw yield of soybean was recorded.

Results and discussion

3.1Impact of conservationtillage on chemicalproperties of soil

The soil pH and EC were significantly differed due to the different tillage treatments (Table 1).The soil pH ranged from 7.63 to 7.69, indicating that the soil was slightly alkaline in reaction. The lower soil pH (7.63) recorded in the crop residue-incorporated treatments may be attributed to the addition of a substantial amount of organic matter through crop residues. During microbial decomposition, organic acids are released, which contribute to a reduction in soil pH. Furthermore, the added organic matter acts as a pH buffer by releasing H + ions, thereby reducing soil alkalinity. The present findings are in agreement with those reported by Kumar etal.(2017). The electrical conductivity varied from 0.24 to 0.29 dS m -1 .The lower EC was observed in (T3)reduced tillage (RT) -broad-bed and furrow every year + pre-and post-emergence herbicide application + crop residue mulch at par with (T1) Conventional tillage (CT)-ploughing once in 3 years +2 pre-sowing harrowing +one hand weeding +opening of furrow with hoe in each rowat 30-35 DAS+ crop residue mulch and the highest EC was observed in (T4) Zero tillage + crop residue mulch. The present findings are in agreement with those reported by Kumar etal. (2017) [12,14] . The significantly highest organic carbon content (6.68 g kg -1 ) was observed in reduced tillage (RT) -pre-sowing harrowing + broad bed and furrow every year + pre-emergence herbicide application + crop residue mulch (T3) and was on par with (T1)conventional tillage with crop residue mulch (6.47g kg -1 ). The lowest organic carbon content in soil was observed in conventional tillage with no crop residue mulch (T2). The increase in organic carbon content in T3 was 12.83% higher as compared to conventional tillage with no crop residue mulch (T2). The improvement in organic carbon was due to the direct incorporation of crop residues, which encourages microbial activity in soil and create favorable environment for them which might have resulted in the increased organic carbon content. The findings are in line with the research findings of Moreno et al.(2006) [19,9,18,19,24] .

3.2Impact of conservation tillage on soybeanyield

The effect of different conservation tillage treatments was significant on seed and straw yield of soybean (Table 2). The highest seed yield (1807 kg ha⁻¹) was recorded under reduced tillage (RT) with broad bed and furrow (BBF) every year+ preand post-emergence herbicide application and crop residue mulch (T3)and was on par with (T1) Conventional tillage (CT) -Ploughing once in 3 years + 2 pre-sowing harrowing + one hand weeding + Opening of furrow with hoe in each row at 30-35 DAS+ without crop residue mulch (1784 kg ha -1 ).The lowest soybean seed yield (1380 kg ha -1 ) was observed in treatment zero tillage + crop residue mulch (T4). The increase in soybean seed yield in T3 was 4.57% and 30.90% higher than in conventional tillage (CT) -pre-sowing harrowing + one hoeing + one hand weeding + no crop residue mulch (T2) and zero tillage + crop residue (T4), respectively. The improved yield under reduced tillage with residue mulch may be attributed to better soil moisture conservation, enhanced nutrient availability, improved soil physical conditionsand increased microbial activity, which collectively promoted better crop growth and productivity. 176.4 111.9

Significantly higher soybean straw yield (1975 kg ha -1 ) was observed in reduced tillage (RT) -broad-bed and furrow every year + pre-and post-emergence herbicide application + crop residue mulch (T3) and was on par with treatment T1, conventional tillage (CT) -Ploughing once in 3 years +2 presowing harrowing + one hand weeding + Opening of furrow with hoe in each row at 30-35 DAS +Crop residue mulch(1896 kg ha - 1 ).The lowest soybean straw yield (1493 kg ha -1 ) was recorded under zero tillage + crop residue mulch (T4). The increase in soybean straw yield in reduced tillage (RT) -pre-sowing harrowing + broad bed and furrow every year + pre-emergence herbicide application + crop residue mulch (T3) was 7.33% and 32.28% higher as compared to conventional tillage (CT) -pre-sowing harrowing + one hoeing + one hand weeding + no crop residue mulch (T2) and zero tillage + crop residue mulch (T4),respectively. Higher soybean straw yield in reduced tillage might be due to crop residue incorporation; during the decomposition process, a series of nutrient transformations takes place due to increased microbial activity, which helps in greater nutrient availability to the crops,resulting in higher yield due to higher uptake of nutrients. 2025) [1,2,3,5,6,12,14,21,23,25] .

Impact of conservation tillage on soil fertility

The available N, P and K was significantly influenced due to the various tillage treatments (Table .3) The significantly highest available N (194.14 kgha -1 ), available P (24.26 kg ha -1 ) and available K (306.11 kg ha -1 ) were observed in treatment T3reduced tillage (RT) -pre-sowing harrowing + broad bed and furrow every year + pre-emergence herbicide application + crop residue mulch, which was on par with conventional tillage with crop residue mulch (T1). The increase in available N content (1.60% and 5.29%), available P content (5.24% and 17.02%), and available K content (0.66% and 2.19%) was recorded in reduced tillage with crop residue mulch (T3) as compared to treatments T1 and T2, respectively. The improvement in available nutrients in reduced tillage with crop residue mulch (T3) might be due to addition of chickpea crop residue. Crop residue addition has improved the soil physical conditions and microbial activity in the soil. The findings agree with the conclusions drawn byKumar et al. [10,12,14,13,16,17,20] .

Conclusion

From the results of the presentinvestigation, it can be concluded that reduced tillage (RT) -broad-bed and furrow every year + preand post-emergence herbicide application + crop residue mulch enhanced nutrient availability and yield of soybean in Vertisols

References

1. Basha SJ, Jayalakshmi V, Reddy AT, Kamakshi N, Ahammed SK. Conservation agricultural practices for enhancing productivity of chickpea (Cicer arietinum L.) in rainfed areas. J Pharmacogn Phytochem. 2018;7(5):17481750.
2. Sonune B, Jadhao S, Kharche V, Mali D, Kadu P, Katkar R, Konde N, Nalge D, Mohod P. Resource conservation practices for sustainable crop productivity and soil quality in shrink-swell soils of Central India. Commun Soil Sci Plant Anal. 2025;56(17):2531-2548. DOI:10.1080/00103624.2025.2522189.
3. Bhattacharyya R, Kundu S, Pandey SC, Singh KP, Gupta HS. Tillage and irrigation effects on crop yields and soil properties under the rice-wheat system in the Indian Himalayas. Agric Water Manag. 2008;95:993-1002.
4. Blaise D, Ravindran CD. Influence of tillage and residue management on growth and yield of cotton grown on Vertisol over 5 years in semi arid region of India. Soil Tillage Res. 2003;70(2):163-173.
5. Dixit AK, Kumar S, Rai AK, Kumar TK. System productivity, profitability, nutrient uptake and soil health under tillage, nutrient and weed management in rainfed chickpea (Cicer arietinum)-fodder sorghum (Sorghum bicolour) cropping system. Indian J Agron. 2015;60(2):205211.
6. FAO. Save and Grow in Practice: Maize, rice and wheat. Rome: Food and Agriculture Organization; 2016.
7. FAOSTAT. FAOSTAT Statistical Database. Rome: Food and Agriculture Organization of the United Nations; 2024.
8. Ghosh BN, Dogra P, Sharma NK, Bhattacharyya R, Mishra PK. Conservation agriculture impact for soil conservation in maize-wheat cropping system in the Indian sub-Himalayas. Int Soil Water Conserv Res. 2015;3(2):112-118.
9. Hati KM, Chaudhary RS, Mandal KG, Mishra AK, Singh RK, Wani SP, Singh P, Pathak P. Effect of land management and cropping systems on runoff, soil loss, soil water dynamics and crop yield in a Vertisol of Central India. J Indian Soc Soil Sci. 2013;61(2):79-88.
10. Lyda H, Sa JCM, Boulakia S, Reyes M, Leng V, Kong R, Tivet FE, Briedis C, Hartman D, Ferreira LA, Magno T, Pheav S. Short-term conservation agriculture and biomass-C input impacts on soil C dynamics. 2015.
11. Kumar R, Paslawar AN. Effect of conservation tillage on biomass partitioning and quality of pigeonpea based intercropping system under Vidarbha region. Bioscan. 2017;12(1):571-574.
12. Kushwa V, Hati KM, Sinha NK, Singh RK, Mohanty M, Somasundaram J, Chaudhary RS, Biswas AK, Patra AK. Long term conservation tillage effect on soil organic carbon and available phosphorus content in Vertisols of central India. Agric Res. 2016;5(4):353-361.
13. Kumar S, Vishwakarma D, Lenka S, Jain RC. Effects of conservation tillage, organics and inorganics on soil fertility in different aggregate soil classes. Ann Plant Soil Res. 2018;20(2):168-171.
14. Lal R. Soil erosion problems on Alfisols in western Nigeria, VI. Effects of erosion on experimental plots. Geoderma. 1981;25:215-230.
15. Lemanowicz J. Phosphatase activity and available phosphorus in soil under winter wheat (Triticum aestivum L.) fertilized minerally. Pol J Agron. 2011;4(1):12-15.
16. Margenot AJ, Paul BK, Sommer RR, Pulleman MM, Parikh SJ, Jackson LE, Fonte SJ. Can conservation agriculture improve phosphorus (P) availability in weathered soils? Effects of tillage and residue management on soil P status after 9 years in a Kenyan Oxisol. Soil Tillage Res. 2017;166:157-166.
17. Moreno F, Murilo JM, Pelegrin F, Giron IF. Long-term impact of conservation tillage on stratification ratio of soil organic carbon and loss of total and active CaCO3. Soil Tillage Res. 2006;85(1-2):86-93.
18. Parihar CM, Yadav MR, Jat SL, Singh AK, Kumar B, Pradhan S, Chakraborty D, Jat ML, Jat RK, Saharawat YS, Yadav OP. Long-term effect of conservation agriculture in maize rotations on total organic carbon, physical and biological properties of a sandy loam soil in north-western Indo-Gangetic plains. Soil Tillage Res. 2016;161:116-128.
19. Patra S, Julich S, Feger KH, Jat ML, Sharma PC, Schwarzel K. Effect of conservation agriculture on stratification of soil organic matter under cereal-based cropping systems. Arch Agron Soil Sci. 2019;65(14):2013-2028.
20. Pooniya V, Biswakarma N, Parihar CM, Swarnalakshmi K, Lamba A, Nath A, Pal M, Jat SL, Satyanarayana T, Majumdar K, Jat RD, Shivay YS, Kumar D, Ghasal PC, Singh K. Six years of conservation agriculture and nutrient management in maize-mustard rotation: Impact on soil properties, system productivity and profitability. Field Crops Res. 2021;260:1-10.
21. Sharifi A, Sadeghnezhad HR, Faraji A. Effect of conservation tillage systems on growth, yield and yield components of soybean. Agric Eng Int CIGR J. 2016;18(3):74-83.
22. Yadav N, Ramesh A, Sharma SK, Sanjeeda I, Joshi OP. Influence of tillage and integrated nutrient management on carbon sequestration in Vertisols under soybean-based cropping systems in central India. Soybean Res. 2014;(Special issue 2):108-119.
23. Zheng C, Jiang Y, Chen C, Sun Y, Feng J, Deng A, Song Z, Zhang W. The impacts of conservation agriculture on crop yield in China depend on specific practices, crops and cropping regions. Crop J. 2014;2(5):289-296.