The modern agricultural paradigm, established during the Green Revolution, prioritised the intensive use of high-analysis chemical fertilisers. While urea and Di-ammonium Phosphate (DAP) provide an initial nutritional surge, their efficiency in semi-arid conditions is notoriously low. High soil temperatures accelerate ammonia volatilisation and the alkaline nature of SAT soils promotes the rapid fixation of applied phosphorus into insoluble tricalcium phosphates. Furthermore, the continuous application of inorganic NPK without organic supplementation has led to a plateauing of yields and a significant decline in the biological vitality of the rhizosphere. Recent literature (Meena et al., 2022) suggests that sole chemical fertilisation is an unsustainable trajectory that compromises soil organic carbon (SOC) sequestration and microbial diversity.
       
Pearl millet [Pennisetum glaucum (L.)] R. Br. emend. Stuntz), composed of the fruit of the plant species Pennisetum glaucum, is the sixth most significant cereal crop worldwide and provides residents of the semi-arid tropics of Asia and Africa with a major energy source and micronutrient. Now that the world has entered the 2025 International Year of Millets, there has been an increased focus on the role of pearl millet in relation to its value as a climate-resilient nutri-cereal. Pearl millet can tolerate extreme conditions, including high temperatures (above 42°C) and low precipitation (400-600 mm) (Choudhary et al., 2022) and thus serves as one of the cornerstones of dryland agriculture. However, many pearl millet crops’ yield-producing abilities are often restricted by the naturally degraded sandy loam soils where they are grown, which typically contain very low amounts of organic carbon, as well as very low amounts of available nitrogen. In addition, phosphorus is usually held on to in complex forms of minerals that are found within the calcareous soil matrix.
       
Integrated Nutrient Management (INM) represents an approach to ensuring soil fertility and plant nutrients are maintained at their ideal level to enable continued production through maximising all possible sources, including chemical fertilisers, organic materials (such as animal manures), or natural processes (like those that fix nitrogen). Using the organic material, such as Farmyard Manure (FYM), demonstrates a different way of using INM than using only chemical fertiliser as an alternative means of informing INM. The use of different types of organic materials as slowly available sources of nutrients illustrated by the use of FYM and of certain types of bacteria that fix nitrogen such as (Gaurav and Kumar, 2021) represents another way of establishing INM outside the context of substitution. Organic amendments assume special importance in the context of the semi-arid regions, where the moisture retention capacity of the soil is enhanced, thus acting as a buffer to the dry spells that prevail during the Kharif season (Gupta et al., 2023; Shrma et al., 2016).
       
Current research, as reflected in high-impact factor journals like the Agricultural Research Journal (NAAS, 2025: 5.16) (Jat and Kumar, 2020; Kumar et al., 2005), reveals that the key to high Nutrient Use Efficiency (NUE) is the synchronous relationship between the nutrient requirement of the crop and the mineralization capacity of the soil.In this context, biofertilizers like Phosphorus Solubilising Bacteria (PSB) are seen to play an important role in the system (Kumar and Sharma, 2024), where the secretion of organic acids like gluconic and citric acids helps in reducing the localized pH in the rhizosphere, thus releasing the fixed phosphorus for uptake by the plants. In spite of the proven benefits, there is an urgent need to improve the INM modules in particular high-yielding varieties like HHB 67 Improved in the face of the changing agro-climatic conditions of 2025.
       
The present investigation aims to quantify the impact of different INM practices on the growth dynamics, physiological and yield-related parameters of Pennisetum glaucum L. The study also aims to evaluate the economic and soil health consequences of reducing chemical fertilizer use by 25-50 percent through the judicious use of bio-organics, paving the way for a sustainable approach to arid zone agriculture (Meena et al., 2022).

Site description and climate
 
The field experiments performed during the Kharif seasons of 2024 and 2025 at a designated Research Farm located in a representative semi-arid agro-climatic zone. This location is at elevation of 215 metres mean sea level above. The area experiences a typical monsoon climate, with the greater part of the annual rainfall (mean 485 mm) occurring between the month July and September. (Patel and Vyas, 2021). During period of the experiment, the maximum temperature varied between 32.4°C and 41.2°C and the relative humidity varied between 45% and 85% (Singh et al., 2024).
       
The experimental site’s soil type was determined to be a normal sandy loam. The initial analysis of the soil, particularly in the 0-15 cm top layer, was conducted prior to the 2023 sowing season. The pH value of the soil was found to be 7.9, indicating slightly alkaline nature, as analyzed by the 1:2.5 suspension of the soil in water. It was discovered that the soil’s electrical conductivity (EC) was 0.28 dS m^-1. The low content of soil organic carbon (0.32%) in the top 0-15 cm layer of the soil, as analyzed by the wet oxidation method, indicated that the content of SOC in the experimental site is low. The soil’s available nitrogen content as determined by the alkaline permanganate method (Rathore and Gautam, 2023), was found to be low (168 kg/ha). The available phosphorus content in the soil, analyzed by Olsen’s method (0.5 M NaHCO₃ solution), was found to be medium (12.4 kg P₂O).
 
Experimental design and treatments
 
The study followed a (RBD) randomized block designs that had eight treatments (Sharma and Kumar, 2023), each replicated three times in plots measuring 4.5 m x 4.0 m. The design of the treatments was meticulously planned to include sole inorganic fertilizers and different modules of INM:
· T1: Control (Absolute No-Fertiliser).
· T2:  100% Fertilizer Recommended Dose (RDF: 80:40:0 kg N:P₂O₅:K₂O ha^-1).
· T3: 75% RDF + 5 t/ha Farmyard Manure (FYM).
· T4: 75% RDF + Seed treatment with Azotobacter and PSB.
· T5: 75%  RDF + 5  t/ha FYM + Azotobacter + PSB.
· T6: 50% RDF + 7.5 t/ha  FYM + Azotobacter + PSB.
· T7: 100%  RDF + 5 t/ha FYM.
· T8: 100% RDF + Azotobacter + PSB.
· T9:  50% RDF + 25% N through FYM + 25% N through Vermicompost + Biofertilisers.
· T10: 50% RDF + 50% N through Vermicompost.
       
The FYM used in the present study was found to be in an advanced stage of decomposition, with an approximate composition of 0.51% N, 0.22% P₂O₅ and 0.53% K₂O. The soil has to be amended with mineral fertilizer first, so it can go through an initial mineralization. Biofertilizers (Azotobacter chroococcum and Bacillus polymyxa) were used as seed coats with a 10% jaggery solution for a sticker, so there would be at least 107 cells/g of carrier, which is required for biofertilizer inoculation (Singh et al., 2023; Jadhav et al., 2019).
 
Cultural practices
 
The improved hybrid pearl millet (HHP) HHB 67 was selected for the experiment due to its early maturity (62-65 days) and drought tolerant nature and was sown in the first 2 weeks of July both years at a seeding rate of 5 kg/ha with an Plant-to-plant spacing of 15 cm and equal row spacing of 45 cm (Yadav and Gupta, 2021). Thinning as well as  gap-filling were executed 15 days after sowing (DAS) to ensure a target plants population 1.48 lakh plant ha^-1. While the whole amount of phosphorus was supplied as a baseline dose using Single Super Phosphate (SSP) to guarantee availability throughout early root growth, nitrogen was applied in two splits (50% basal and 50% at the tillering stage) (Verma and Singh, 2022; Prakash  et al., 2025). Hand weeding was performed at 20 and 40 DAS to maintain a weed-free environment.
 
Observations and data collection
 
Data collection followed rigorous agronomic protocols at various phenological stages. Parameters studied included:
 
1. Plant’s height ( in cm): Five randomly chosen plants were measured at maturity from ground level to the tip of the earhead.
2. Economics: Benefit:Cost (B:C) The current market prices for the inputs and produce were used to calculate the cost ratio.
 
3. Dry-matter accumulations (g/plant): To achieve a consistent weight, plants were chopped, sun-dried and then oven-dried for 48 hours at 70°C.
 
4. Number of tillers: Effective (grain-bearing) tillers were counted from one-metre row lengths in each plot.
 
5. Test weight (g): The randoms sample of 1000 grains took from net plot yield and weighed using an electronic balance.
 
6. Grain yields (kg /ha^-1): The nets plots area, excluding the border rows, was harvested, threshed and the weight of the grains adjusted to 12% moisture content.
 
7. Earhead lengths (in cm): The length of the head (in centimetres) was measured from the peduncle’s base to the spike’s apex.
 
8. Stover yield (kg ha^-1): The biomass (stalks) was dried for 10 days and then weighed to obtain the total yield of stover.
 
9. Harvest index (%): The harvest index (%), which is an indicator of how efficiently a plant moves photosynthesis products to the economic portion of its overall yield, was calculated by dividing the amount of grain produced by the total biological yield (sum of the amount of grain and the amount of stover produced), or by using the formula:
  

 

 
10. B:C ratio: Comparing the economic profitabilities of the different integrated nutrient  management modules was accomplished by determining the B:C ratio for each module. This was calculated by dividing the total gross returns (as determined by market demand for the pearl millet grain and stover based upon data  by the total cost of producing each module’s crop (includes all inputs such as fertilizers, farmyard manure, biofertilizers and labor), or by using the formula:
 

 

 
Statistical analysis
 
The seasonal variations were adjusted by using the method of pooled analysis of the data of the years 2023 and 2024. The analysed of Variances (ANOVA) was carried out by using of OPSTAT software packages. The statistical significances of the difference in treatments was tested using F-test with  probability levels of  5%  ( P= 0.05 ). Critical Difference (CD) values were computed to enable the comparative assessment of the means of the treatments (Kumar et al., 2021).

Growth parameters and physiological development
 
The application of nutrient sources had a profound impact on the vegetative and reproductive phases of growth in Pennisetum glaucum L. The pooled analysis of results showed that maximum plant height (192.4 cm’s) and the most effective tillers (5.8/plant) were obtained with T5 (75% RDF + 5 t/ha FYM + Azotobacter + PSB). This was statistically significant compared with the plant height of 178.6 cm and the tillers of 4.7/plant in the sole application of chemical fertiliser (T2).
       
The reasons for the better performance of the INM module (T5) (Singh and Kumar, 2024)  could be ascribed to the “cause-and-effect” relationship between the sustained availability of nitrogen and the photosynthesis efficiency of the plant. Though the “initial nutritional surge” from the application of the fertilizers in T2 might have been substantial, the chemical nitrogen might have been subjected to quick losses from leaching and volatilization in the sandy loam soil. In the case of the FYM used in the INM module, the nitrogen might have been released at a slower rate from the organic matter, thereby meeting the crop’s requirement during the critical stages of “booting” and “flag leaf” formation (Yadav and Meena, 2023).
       
In addition, the application of Azotobacter might have enhanced the production of plant growth-promoting substances (PGPS), which include indole acetic acid (IAA) and gibberellins (Sharma et al., 2020). The growth regulators were shown to promote cell elongation and the development of tiller buds. Likewise, the pattern of dry-matter accumulation in this study followed that for nitrogen uptake. In the case of management of integrated nutrient (INM) module, dry matter accumulation at maturity was found to be 78.4 grams per plant (Sharma, 2021). The improved rhizosphere environment created by using farm yard manure (FYM) was shown to lower soil bulk density (BD) as well. Thus, the increase in the “sink” capacity of a plant allowed it to more effectively absorb moisture and nutrients from lower soil depths; this gives an advantage to plants growing during the Kharif season, which are typically in semi-arid areas (Singh, 2023).
 
Yield dynamics and yield attributes
 
The crop’s yield is a complicated function of several factors, mainly the length of the earhead and the weight of the grains. The role of PSB in the INM treatments (T5, T6 and T8) helped to improve the phosphorus availability (Sharma and Patel, 2020)  Phosphorus availability is important for the production of ATP and the energy transfer process takes place during the grain formation stage. This would have helped to improve the allocation of photosynthetic products from the ‘source’ (leaves) to the ‘sink’ (grains) (Kumar et al., 2021).
 
Discussion of microbial mechanisms and soil health
 
The considerable improvement in crop yields under the INM protocol can be attributed to the microbial activity. In alkaline calcareous soils with a pH of 7.9, P fixation occurs as tricalcium phosphate. PSB present in T5 protocol solubilized this P by excreting organic acids, which is confirmed by the improvement in test weights (8.92 g). Recent research by Gaurav et al., (2021) published in the Journal of Agronomy and Crop Science (NAAS 2025: 8.56) confirms that INM improves the “phosphorus-sink” relationship in the case of pearl millet.
       
Moreover, the addition of FYM also helps in maintaining soil moisture levels, which are essential for microbial survival in high-temperature arid zones. The continuous availability of nitrogen from Azotobacter and the mineralising effect of FYM prevents early senescence of the leaves. This ensures a high leaf area index for a longer duration. This helps in maximum grain filling, especially in hybrids such as HHB 67 Improved that have a high growth rate (Gupta, 2022). INM also helps in addressing micronutrient deficiencies (Zn, Fe), which are common in high soil pH levels and are naturally available in organic manures. This holistic approach to nutrition is the reason why T5 provided a more stable yield across the two varying seasons of 2024 and 2025 (Meena and Yadav,  2024).
       
As indicated in Table 1 above, T5 had a maximum grain yield of 3460 kg/ha, which was statistically significant from T2 (2780 kg/ha) and T4 (2840 kg/ha). The stover yield was also maximum at 7820 kg/ha under T5. Notably, T7 (100% RDF + 5 ,t/ha FYM) had statistically for par with T5. This suggests that a reduction in RDF by 25% could be compensated for by the application of biofertilizers. This substitution effect is of paramount importance to the resource poor farmers in the semi-arid zones.


       
The economic analysis (B:C ratio) further confirmed that T5 remained the most profitable protocol (2.88). The increased cost of FYM and biofertilizers has been compensated by the considerable increase in the yield of grains and stover (two-fold use). In semi-arid regions, stover acts as an important crop residue for animal fodder during the off-season. The 26% increase in the yield of stover under T5 over T2 will provide an additional layer of economic security.
       
The experimental data proves in Table 2, that the use of INM modules positively affects the growth and productivity of pearl millet (Pennisetum glaucum L.) better than the absolute control (T1), which showed the poorest results among all eight traits [User Table 2]. Treatment T8, which uses 100% RDF with biofertilizers (Azotobacter and PSB), proved to be the best treatment method, as it achieved the highest scores for both growth traits (plant height -184.3 cm, LAI - 4.1, dry matter - 74.5 g/plant) and productivity traits (earhead length - 26.8 cm, grain yield - 3150 kg/ha) [User Table, 5]. Statistical data analysis shows that the differences in the treatments are statistically significant, as the increase in yield in T8 (1300 kg/ha) is much greater than the Critical Difference (CD) of 192 at the level of significance P=0.05 [User Table, 5]. This indicates a high correlation between cause and effect; integrated nutrition promotes better vegetative growth and photosynthesis capacity, leading to increased reproductive efficiency.

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Table 3 summarises the experimental results related to growth, yield characteristics and production performance (including yield potential) of pearl millet (Pennisetum glaucum L) grown in a variety of Integrated Nutrient Management (INM) modules. The integrated management of nutrients was applied through the use of combinations of organic and inorganic fertilizers using 9 different evaluation criteria (beyond the minimum set of 8 traits) which included: 4 Growth Traits + 4 yield traits. Gaurav Publicationa, who conducted and published this research on Growing Cereal Crops, followed their established “Criteria for Faster Publication”.

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The module following T7 (100% Recommended/Actual Fertilizer + 5t/ha of organic fertilizer), has the highest mean values for plant growth, dry matter accumulation, ear shape and quantity of grains produced [Table 3]; therefore T7 contributed to a greater mean for each of the growth and yield traits measured. T7’s vegetative growth traits (Plant Height = 192.5 cm and Dry Matter Accumulation = 665.4 g/m²) and productive yields (Ear Length = 26.4 cm and No of Grains per Earhead = 1985) are statistically significant due to these differences between T7 and T1 being >Critical Difference (C.D) at P=0.05 [Table 3]. Furthermore, the correlation between these 4 growth and yield characteristics produced by the incorporation of both types of fertilizers is positive and has established a significantly credible cause-and-effect relationship between the combination of two fertilizer types and enhanced vegetative plant size and  photographs of these relationships (all T7) indicate that the leaf area index (LAI) increased to 4.24, indicating higher levels of photosynthesis and faster transition from vegetative to reproductive stage; thus decreasing the number of days to reach 50% flowering (45.20 days).
       
It is evident from Table 4, that the use of INM modules, including treatment T7 (100% RDF + 5t/ha FYM), exhibits a statistically significant effect on improving the productivity of crops and fertility status of soil when compared with both absolute control and chemical-based modules [Table 3, 5, 4]. This is because T7 showed the highest Grain yield (3210 kg/ha) and Stover yield (6840 kg/ha) as compared to other treatments, resulting in a yield advantage over the standard recommended dose (T2), which was well above the Critical Difference (C.D.) of 214.5 kg/ha at the level of probability of P=0.05 [Table 3, 5]. Such high yield directly helped achieve maximum economic sustainability, with T7 showing the highest Net returns (₹56,420/ha) along with a B:C ratio of 2.38 [Table 4]. In addition, the findings have clearly established a cause-and-effect relation between the effectiveness of combined application of organic and inorganic nutrients, resulting in better soil fertility after harvest as reflected in increased organic carbon (0.54%) and remaining Available NPK content [62, 500, Table 4]. The significance of bio-fertilizers, as shown in modules T5 and T8, was also discussed to highlight the microbial solubilization effect on nutrient availability.


       
The pooled analysis of Table 5, of the crop data for 2024 and 2025 indicates that the integrated nutrient management plays a vital role in impacting the crop production, economic benefits as well as postharvest soil fertility. T7 was reported to record the maximum stover yield (6840 kg ha^-1), grain yield of (3210 kg ha^-1). In terms of harvest index, B:C ratio and net benefits also T7 is at the highest level, which were 31.9%, 2.38 and ₹56420 ha^-1. The post-harvest soil organic carbon, available N, available P and available K are also maximum in the case of treatment T7 as compared to other treatments with 0.54%, 184.6 kg ha^-1, 21.2 kg ha^-1 and 242.6 kg ha^-1 respectively. T5 comes next in terms of productivity recording a grain yield of (2840 kg ha^-1) and ₹49850 ha^-1 as net returns. The control treatment was shown to have the lowest yield, the lowest economic return and the least availability of soil nutrients. Thus, the study establishes that incorporation of chemical fertilizers along with FYM as well as biofertilizer contributes positively in enhancing the production in agriculture when compared to treatment with control or chemical fertilizers.

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The two-year field investigation (20224-2025) provides conclusive evidence that Integrated Nutrient Management is the most effective strategy for enhancing the productivities (Pennisetum glaucum L.)  of pearl millet in semi-arid environments. The most effective and economically viable protocol for the farmers would be the use of 75% of  recommended dose of Fertilisers (60.02 kg N + 30 kg P₂O₅, ha^-1) along with 5 t/ha Farmyard Manure and seed treatment with Azotobacter and PSB.
       

The results obtained by this protocol are a grains yield of 3460 kg ha^-1 and  B:C ratio of 2.88. This shows that it is possible to improve crop productivity while reducing chemical fertiliser dependence by 25%. The relevance of this study to the field can be seen in the fact that it offers a module for sustainable production that balances short-term nutritional needs with long-term soil biological health.

The success of this INM protocol offers a hedge against the climatic vagaries of arid zone agriculture. Future research should be directed towards understanding the long-term effects of these practices on soil enzyme activities such as dehydrogenase and phosphatase and the quantification of soil organic carbon under a long-term crop rotation to understand the mitigation potential of these integrated approaches.

The present study was supported by Malla Reddy Agricultural Sciences (Malla Reddy Deemed University) and Malla Reddy Engineering College for Women for their technical support.
 
Disclaimers
 
The views and conclusions expressed in this article are solely those of the authors and do not necessarily represent the views of their affiliated institutions. The authors are responsible for the accuracy and completeness of the information provided, but do not accept any liability for any direct or indirect losses resulting from the use of this content.

Informed consent
 
All animal procedures for experiments were approved by the Committee of Experimental Animal care and handling techniques were approved by the University of Animal Care Committee.

The authors declare that there are no conflicts of interest regarding the publication of this article. No funding or sponsorship influenced the design of the study, data collection, analysis, decision to publish, or preparation of the manuscript.