Mung bean [Vigna radiata (L.) Wilczek] is the paradigm of pulse crop growth, that is, it crops under high special rates of biological nitrogen fixation (Niranjan et al., 2023) a condensed growth cycle and rapid biomass growth due to effective photosynthesis. Mung bean is planted on the global level, with an area of approximately 8.5 million ha and yields of 7.2 million tonnes in 2021 (FAO, 2023). However, in most of Africa including parts of Asia, its yield is less than 1.5 t ha ^-1 and the 0.5 t ha ^-1 to 1.5 t ha ^-1 range is always achieved under sub-optimal soil conditions and under minimal management (Maphosa et al., 2022).
       
Integrated nutrient management (INM) has provided an affordable agronomic solution, it is a synergistic method of utilising both organic and chemical nutrient supplies to achieve maximum crop yields and system sustainability. Empirical studies confirm that farmyard manure (FYM) improves soil structure, increases nutrient bioavailability and promotes carbon sequestration (Krause et al., 2024). For example, in key production regions like Ethiopia and the aral sea area  applying 5-10 t ha^-1 FYM alongside inorganic fertilizers increased mung bean yields by 15-25% compared to synthetic fertilizers alone (Shah et al., 2024). Modern innovations like nitrogen-fixing and phosphate-solubilizing microbial consortia further optimize nutrient use. Trials show these biofertilizers, when combined with carrier materials like aggregated sand, boost mung bean yields by 9-18% over conventional NPK fertilization. Similarly, nano-phosphorus (nano-P) fertilizers enhance phosphorus uptake efficiency, increasing yields by 12% compared to traditional P sources (Kumar, 2024).
       
The current field experiment aims at assessing the relative effect of crop-synchronized NPK addition and FYM fertilizing, combined with microbial consortia and nano-P fertilization, versus monolithic NPK fertilization. The hypothesis is that the combined fertilization regimes will overcompensate the single NPK fertilization in aspects of crop growth, the composition of the yield, the acquisition of nutrients and soil biology.

Experimental site and methodology
 
The experiment was conducted during the Kharif season of 2021-22 at the Crop Research Farm, CSA University of Agriculture and Technology, Kanpur, Uttar Pradesh, located in the Gangetic alluvial plains of central Uttar Pradesh (Fig 1). The soil was Fluvisol with loam texture, pH 7.8 and available N, P and K of 225, 18.2 and 278 kg ha^-1, respectively. The study was laid out in a factorial randomized block design (FRBD) with three replications using two mungbean varieties (V₁: Pusa 1431; V₂: Virat) along with six integrated nutrient management treatments: M₁ (100% NPK: 20-40-20 kg ha^-1), M₂ (75% NPK + FYM @ 5 t ha^-1), M₃ (75% NPK + FYM @ 5 t ha^-1 + NPK consortia), M₄ (75% NPK + FYM @ 5 t ha^-1 + nano-phosphorus spray at 25 DAS), M₅ (75% NPK + NPK consortium + Nano-P spray at 25 DAS) and M₆ (75% NPK + FYM @ 5 t ha^-1 + NPK consortium + Nano-P spray at 25 DAS). The field was prepared by ploughing, harrowing and leveling. Seeds were sown at 30 cm × 10 cm spacing with a seed rate of 20 kg ha^-1 and fertilizer was applied as per treatment using urea, DAP and MOP. FYM was incorporated 15 days before sowing, while nano-phosphorus (500 ppm, 30 nm) was applied as foliar spray at 25 DAS. Standard agronomic practices were followed throughout the crop period. IFFCO’s NPK consortium contains N-fixing, phosphate-solubilizing and potassium-mobilizing bacteria. Nano-phosphorus (30 nm, 500 ppm) provides high-efficiency, bioavailable nutrition for improved crop uptake. NPK consortium and Nano-phosphorus have obtained from the Indian certified company- IFFCO (Indian Farmer Fertilizer Cooperative Limited).


 
Observations recorded and soil biological analysis
 
Plant height, dry matter accumulation, yield attributes, grain and biological yields, harvest index, phosphorus content, uptake and benefit:cost ratio were recorded at harvest. Plant height was measured from five randomly selected plants plot^-1, while grain and biological yields were estimated from the net plot area and expressed in kg ha^-1. Phosphorus content (%) in grain and straw was determined using the vanado-molybdo phosphoric yellow color method and total P uptake was calculated accordingly. Soil samples collected before and after harvest from 0-15 cm depth were air-dried, sieved (2 mm) and analyzed for soil biological properties including microbial biomass carbon (MBC) using the fumigation-extraction method described by Vance et al. (1987).
 
Statistical analysis
 
The recorded data were statistically analyzed using ANOVA in IBM SPSS statistics. Treatment means were compared using the critical difference (CD) test at p≤0.05 following Gomez and Gomez (1984).

Growth parameters
 
Inter-varietal differences were also significant, with Pusa 1431 (V₂) outperforming virat (V₁) across all growth stages (Table 1). At harvest, Pusa 1431 (V₂) plants were taller, exhibited more branches plant and accumulated higher dry matter (10.6 g plant) compared to virat (V₁). These observations align with reports of substantial genotypic diversity in mungbean regarding growth development and nutrient use efficiency (Hasanain et al., 2020). The superior performance of Pusa 1431 (V₂) stems from its inherent genetic vigor, facilitating enhanced nutrient uptake and biomass accumulation (Ali et al., 2024 and Arya et al., 2024).


       
The most effective nutrient management treatment was M₆ (75% NPK + FYM @ 5 t ha^-1 + NPK consortia + Nano-P spray at 25 DAS), which recorded the highest plant height, branches plant^-1 and dry matter accumulation (11.2 g plant^-1) at harvest. This superior performance likely stemmed from the synergy among organic, inorganic (reduced NPK), biofertilizers and nano-fertilizers, which provided sustained nutrient release, improved soil health and enhanced nutrient use efficiency (Cathrine et al., 2024). Foliar nano-P application at the critical 25 DAS stage boosted P nutrition, root proliferation, photosynthetic activity and overall vegetative growth (Dhiman et al., 2025). Nano-fertilizers’ nanoscale particle size and high surface area further facilitate superior nutrient absorption and plant physiological functions (Channab et al., 2024).
 
Yield attributes and yield
 
Varietal analysis of yield attributes demonstrated that Pusa 1431 (V₂) significantly outperformed virat (V₁) across major yield parameters, reflecting its superior genotypic potential. Pusa 1431 (V₂) recorded higher number of pods plant^-1 (13.8), pod length (8.2 cm), seeds pod^-1 (7.1), grain yield (11.0 q ha^-1) and straw yield (33.6 q ha^-1) as compared to Virat (V₁). However, test weight and harvest index showed only marginal differences between the two varieties. The superior performance of Pusa 1431 (V₂) may be attributed to its better vegetative growth, efficient nutrient utilization, enhanced photosynthetic activity and greater adaptability to prevailing agro-climatic conditions Gogoi et al., (2024). Pusa-1431 (V₂) recorded significantly higher grain and straw yield than virat (V₁). Pusa-1431 (V₂) exhibited a grain yield of 11.0 q ha^-1, which was 11.8% higher than V₁ (9.7 q ha^-1) and a straw yield of 33.6 q ha^-1, representing a 12.2% increase over V₁ (29.5 q ha^-1). Among the nutrient management treatments, M₁  (75% NPK + FYM @ 5 t ha^-1 + NPK consortia + Nano-P spray at 25 DAS) produced significantly higher grain yield (12.4 q ha^-1) and straw yield (35.7 q ha^-1). The treatment recorded 49.4% higher grain yield and 30.8% higher straw yield over M₁ [100% NPK (20 N, 40 P2O5, 20 K₂O kg ha^-1)], which produced grain and straw yields of 8.3 and 27.3 q ha^-1, respectively (Fig 2). The superior yield performance of Pusa-1431 (V₂) may be attributed to its better photosynthetic efficiency, enhanced root growth and greater nutrient uptake capacity, which collectively improved vegetative growth and assimilate production. Increased leaf area and better plant vigor under V₂ likely contributed to higher grain and straw yields. The enhanced yield under M₆ (75% NPK + FYM @ 5 t ha^-1 + NPK consortia + Nano-P spray at 25 DAS) may be due to the integrated effect of inorganic fertilizers, FYM, NPK microbial consortia and Nano-P application. The combined use of nano-fertilizers and microbial consortia probably improved nutrient availability, soil microbial biomass, nutrient uptake and root proliferation, thereby enhancing crop growth and productivity. Similar findings were also reported by (Karunakaran et al., 2024; Upadhyay et al., 2025 and Shiny et al., 2025). However, the magnitude of yield improvement was primarily influenced by the nutrient management strategy, particularly the integration of Nano-P and microbial consortia, rather than the varietal effect alone. Similar findings were also reported by Hasanain et al., (2020); Kumar et al., (2024); Priya and Babu (2021) and Sawarkar et al., (2025).


 
Phosphorus content in grain, straw and total uptake
 
Phosphorus analysis further confirmed the varietal superiority of Pusa 1431 (V₂) over Virat (V₁), with V₂ recording higher phosphorus concentrations in both grain and straw, indicating better phosphorus uptake and utilization efficiency (Table 2). Specifically, Pusa 1431 (V₂) registered 3.84 kg ha^-1 by grain and 6.59 kg ha^-1 by straw, whereas Virat (V₁) recorded 4.56 kg ha^-1 by grain and 8.13 kg ha^-1 by straw. This superiority of Pusa 1431 (V₂) may be attributed to its inherent genetic potential for improved phosphorus absorption, root exudation and nutrient-use efficiency, as supported by previous studies on crop nutrient acquisition and soil resource utilization. Among the nutrient management treatments, M₆, which integrated FYM, NPK consortia and nano-P spray, recorded the highest phosphorus uptake in both grain and straw. The treatment M₆ produced 0.43% P content by grain  and 0.25% content by straw, surpassing M₁, which recorded 0.36 % P content by grain P and 0.25%  P content by  straw. The enhanced performance of M₆ may be due to the complementary action of organic manure for gradual nutrient release, biofertilizers for nutrient mobilization and nano-P spray for improved solubility, foliar absorption and reduced fixation, thereby increasing phosphorus availability and translocation within the plant (Singh et al., 2024, Singh et al., 2026 and Balveer et al., 2026).


 
Benefit/cost ratios
 
Pusa 1431 (V₂) showed better overall performance than virat (V₁) and this superiority was reflected in both productivity and economic return (Table 2). The variety’s stronger growth, higher yield and better phosphorus uptake likely contributed to improved profitability under the integrated nutrient treatments. Among nutrient management options, M₆ recorded the highest benefit:cost ratio (2.35), followed by M₄ (2.25) and M₃ (2.13). All integrated treatments maintained BCR values above 2.0, confirming that these practices were economically worthwhile despite the added cost of biofertilizers and nano-P. The strong performance of M₆ can be explained by its combined effect of NPK,FYM, NPK consortia and Nano-P, which improved nutrient availability, phosphorus uptake and final yield. This aligns with earlier findings that integrated nutrient management can enhance both crop productivity and farm economics (Kumar et al., 2023; Cathrine et al., 2024 and Rajitha et al., 2024).
 
Soil biological parameters
 
The microbial biomass carbon (MBC), dehydrogenase activity (DA)  and soil respiration were significantly higher in variety Pusa 1431 (V₂), with values of 213.1 mg  ha^-1, 2.54 mg TPF g^-1 h^-1 and 33.9 mg CO₂ kg^-1 day^-1, respectively, compared to Virat (V₁) , which recorded 198.3 mg kg^-1, 2.18 mg TPF g^-1 h^-1 and 29.6 mg CO₂ kg^-1 day^-1. This higher soil biological activity under Pusa 1431 (V₂) may be attributed to its superior genetic traits, including a vigorous root system, greater root exudation and improved nutrient mobilization, which support beneficial microbial proliferation and activity. Among the nutrient management treatments, M₆ recorded the highest microbial biomass carbon (230.4 mg kg^-1), dehydrogenase activity (2.73 mg TPF g^-1 h^-1) and soil respiration (36.7 mg CO₂ kg^-1 day^-1). This superior performance likely resulted from the combined application of FYM, NPK consortia and Nano-P, which improved soil organic matter, nutrient recycling, enzymatic activity and microbial proliferation (Table 3). These results are consistent with earlier reports showing that integrated nutrient management enhances soil biological health and nutrient availability (Cathrine et al., 2024; Kumar et al., 2022; Khandare et al., 2025;  Tiwari et al., 2024 and Rajitha et al., 2024).

The results showed that integrated nutrient management combining organic manure, reduced inorganic fertilizers, microbial consortia and nano-phosphorus significantly improved mungbean growth, yield, phosphorus uptake, economic returns and soil biological activity compared to sole chemical fertilization. The treatment with 75% recommended NPK + FYM @ 5 t ha^-1 + NPK consortium + nano-P spray at 25 DAS was most effective in enhancing yield attributes, nutrient use efficiency (NUE) and soil enzyme activity. Among varieties, Pusa-1431 performed better than Virat under integrated nutrient treatments, indicating higher adaptability and nutrient efficiency. Overall, the study suggests that integration of organic, inorganic, bio-and nano-fertilizers can reduce dependence on full chemical fertilizer doses while sustaining soil health and productivity in mungbean. Integrated nutrient management thus offers a sustainable and economically viable approach for the Indo-Gangetic plains. Further long-term studies are needed to assess its impact on soil microbial diversity, nutrient cycling and carbon dynamics.

The authors extend their appreciation to Ongoing Research Funding program - Research Chairs (ORF-RC-2026-5514), King Saud University, Riyadh, Saudi Arabia.
       
The authors sincerely acknowledge the contributions of all co-authors in the conception of the study, data collection, analysis, interpretation of results and manuscript preparation. Their valuable inputs and collaborative efforts contributed significantly to the successful completion of this research.
 
Disclaimers
 
The views expressed in this article are those of the authors and do not necessarily reflect those of their affiliated institutions. The authors are responsible for the content and disclaim liability for any direct or indirect use of the information provided.

The authors declare no conflict of interest.