The disposal of crop residues from agricultural fields is often seen as a burden due to the difficulties involved. However, this study aims to turn pigeonpea stalks into biochar, which can serve as a fuel substitute and soil amendment to sequester carbon. Different pyrolysis methods were employed to investigate the variations in yield, physicochemical characteristics, and higher heating value (HHV) of biochar produced from pigeonpea stalks. The biochar produced using a muffle furnace exhibited higher fixed carbon and ash content. These characteristics make it beneficial for restoring degraded agricultural soils by enhancing carbon sequestration. In addition, the muffle furnace biochar demonstrated a total potential carbon ranging from 262.8 to 264.3 g of carbon per kilogram of biochar, along with a CO₂ reduction potential ranging from 77.17 to 79.68 CO₂ eq per kg. Both the European Biochar Certificate and the International Biochar Initiative confirmed the agronomic abilities of the biochar and its compliance with the highest quality standards for soil carbon sequestration, with 0.11 H/C and 0.7 O/C ratios. Furthermore, biochar produced by muffle furnace from pigeonpea stalks exhibited superior fixed carbon recovery efficiency (181.66 to 184.62%), densification (5.86 to 6.83%), energy density (1.77 to 2.06%), energy retention efficiency (54.80 to 56.64%), fuel ratio (18.95 to 22.38%), and HHV (30.66 to 32.56 MJ kg⁻¹). Additionally, it had lower H/C and O/C ratios, suggesting its potential as an alternative solid fuel. The results of the characterization of biochar with scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) revealed that the biochar samples prepared with both the methods had carbonyl (C=O), C=C, and aromatic C-H functional groups; however, the biochar prepared in the muffle furnace had more porosity. In summary, this study highlights the potential of using pigeonpea stalks to produce biochar, which can be utilized as a renewable fuel substitute and soil amendment to sequester carbon. The biochar derived from the muffle furnace exhibited desirable physicochemical characteristics, high carbon content, and excellent energy properties, making it a promising option for various applications.

Nano-biochar, a highly porous and innovative material derived from biomass, presents significant opportunities for sustainable agriculture and environmental remediation. Its unique sponge-like structure enables exceptional carbon capture and sequestration, contributing to long-term improvements in soil fertility and acting as a vital tool in climate change mitigation. This review explores the properties and production methods of nano-biochar, highlighting its enhanced nutrient retention, controlled release capabilities, and superior water-holding capacity compared to traditional biochar. These characteristics not only enhance plant growth and agricultural productivity but also promote a healthier soil ecosystem by stimulating microbial activity. Furthermore, nano-biochar's ability to adsorb heavy metals and organic pollutants offers promising applications in soil and water remediation, thus preventing environmental contamination. Despite its numerous advantages, the review identifies critical knowledge gaps regarding the long-term ecological impacts of nano-biochar and the best practices for its production and application. The paper calls for further research to address these challenges and optimize the use of nano-biochar, ensuring its responsible development within agricultural systems. By integrating insights from current literature, this review contributes to a comprehensive understanding of nano-biochar's potential and outlines future research directions to enhance its effectiveness in promoting sustainable agricultural practices.

Legumes play a significant role in sustainable agriculture through their ability to improve soil fertility and health. With a mutual symbiotic relationship with some bacteria in soil, they can improve nitrogen (N) amount through biological N-fixation (BNF). But to maximize such functions, legumes need more phosphorus (P) as it is required for energy transformation in nodules. Besides, P also plays a significant role in root development, nutrient uptake and growth of legume crops. A field experiment was conducted during rainy (kharif) season of 2019 at IFS unit, College of Agriculture, (University of Agricultural Sciences, Dharwad), Vijayapur, Karnataka to study the effect of different combination of organic sources on phosphorus dynamics of blackgram [Vigna mungo (L.) Hepper]. Among different treatments, the application of vermicompost + ghanajeevamrutha @ 100% RDP + Rhizobium + PSB recorded significantly higher soil available phosphorus (36.30 kg/ha) and uptake by blackgram (16.08 kg/ha). This study has demonstrated the dynamics of phosphorus through different organic sources in blackgram.

Food grain production has multiplied over the last two decades in India, but natural resources are overexploited in modern farming. Farmers, especially those with small and marginal holdings, are suffering losses more often than not, the cost of production is increasing year after year, and profits are not up to the necessary levels. To address such challenges, there has been a broad recognition of the importance of employing farming system approaches in research. The cultivation of cropping systems with orchard crops and livestock components can play a significant role in the optimal utilization of resources, enhancing energy use efficiency as well as the eco-efficiency index, and reducing carbon footprints. This study was carried out to create a suitable IFS model with high economic and energy efficiency for small-holder farmers in India’s southern plateau and hills with a negligible impact on the environment. The following were the seven models: M₁: Rice − Groundnut; M₂: Rice − Groundnut, Pigeonpea + Sweetcorn (1:3) − Bajra, Bt cotton + Greengram (1:2) − Maize; M₃: Rice − Groundnut, Pigeonpea + Sweetcorn (1:3) − Bajra, Pigeonpea + Maize (1:3) − Sunhemp; Napier grass, Sheep (5 + 1); M₄: Rice − Groundnut, Pigeonpea + Sweetcorn (1:3) − Bajra, Bt cotton + Greengram (1:2) − Maize, Pigeonpea + Maize (1:3) − Sunhemp, Poultry unit; M₅: Guava, Hedge Lucerne, Napier grass, Bt cotton + Greengram (1:2) − Maize, Sheep (5 + 1); M₆: Guava, Bt cotton + Greengram (1:2) − Maize, Rice − Groundnut, Poultry; M₇: Rice − Groundnut, Pigeonpea + Sweetcorn (1:3) − Bajra, Pigeonpea + Maize (1:3) − Sunhemp; Napier grass, Hedge lucerne, Poultry (100), Sheep (5 + 1). Model M₁ was used to represent the local region, and the other models were compared in terms of economics, energetics, greenhouse gas emissions, and employment creation. The M₇ and M₃ models, according to the results, have higher economic efficiency (₹342.3 day⁻¹, ₹263.7 day⁻¹), increase output energy (228,529 and 183,231 MJ) net energy (258,184 and 198,920 MJ), produce net negative emissions (−2842 and −2399 kg CO₂ eq.), and create jobs year-round (112.5 and 110.5 man days year⁻¹), respectively. This is primarily because they have multiple highly efficient components that make them viable for Telangana’s small and marginal farmers.

Background: Concerning fertilization, the pulse crops are more responsive to organic manures but indiscriminate and continuous use of chemical fertilizers has venomous effects on physical, chemical and biological properties of the soil thereby affecting the sustainability of crop production, besides causing environmental pollution. Methods: The study aimed at understanding the effect of different organic amendments on nutrient dynamics of black gram (Vigna mungo), which was carried out at the IFS unit, College of Agriculture, Vijayapur, during Kharif-2019 to study the effect of different combinations of organic sources on nutrient availability, nutrient uptake and soil microbial load in black gram. Result: The application of vermicompost + ghanajeevamrutha @ 100% RDP + Rhizobium + PSB recorded significantly higher soil organic carbon (SOC) (0.70%), soil available nitrogen (291.39 kg ha-1), phosphorus (36.30 kg ha-1) and potassium (580.53 kg ha-1) and significantly higher uptake of nutrients i.e., nitrogen (52.07 and 75.43 kg ha-1), phosphorus (10.12 and 16.08 kg ha-1) and potassium (37.67 and 55.42 kg ha-1) at 45 and 75 DAS compared to all other treatments. Similarly, application of FYM + vermicompost @ 100% RDP + Rhizobium + PSB has recorded the highest microbial count of bacteria [24.40 × 106 CFU (Colony Forming Units) g-1], fungi (17.0 × 103 CFU g-1) and actinomycetes (7.50 × 103 CFU g-1), demonstrating the importance of usage of organics for improving the nutrient availability, uptake and microbial load in black gram.

Present study for investigating the role of organic amendments on the growth and production of the black gram (Vigna mungo). The findings of the research illustrate that, the application of vermicompost + ghanajeevamrutha based on 100 % RDP + Rhizobium + PSB documented a significantly greater Dry matter yield (2740 kg/ha), number of pods/plant (19.33), number of seeds/pod (6.33), the grain yield (701.33 kg/ha), the haulm yield (2038.76 kg/ha) as compared to others and higher gross returns (?. 54540 ha-1), net returns ( ?. 23083 ha-1) and Benefit-Cost ratio (1.74) in black gram production.