Pigeonpea (Cajanus cajan L.) is a significant legume crop widely cultivated in semi-arid tropical regions, valued for its drought resistance, capacity to enhance soil fertility via biological nitrogen fixation and provision of high-protein food and fodder (Dash et al., 2024). Pigeonpea is vital for nutritional security and the maintenance of soil health in India, especially within rainfed agricultural systems. Notwithstanding its agronomic and ecological importance, Pigeonpea productivity is unsatisfactory due to ineffective crop management strategies, particularly with planting geometry and nutrient inputs (Bhardwaj et al., 2023). The planting pattern is a crucial agronomic element that affects crop development, resource utilisation efficiency and ultimately output. Optimal spacing allows better light interception, efficient canopy structure and less intra-specific competition. Conventional sowing techniques can result in inadequate plant density and insufficient aeration, hence limiting production potential (Venkatesh et al., 2023). Nutrient management is crucial for achieving higher productivity. Depending only on synthetic fertilisers may result in nutritional imbalances and declining soil health over time. Integrated nutrient management (INM), which combines organic manures, biofertilizers and chemical fertilizers, is gaining interest for increasing nutrient availability, improving soil microbial activity and maintaining long-term soil fertility (Math et al., 2020). Although many studies evaluate the impacts of planting geometry and fertilizer management on pulse crops, the synergistic influence of these variables on yield, nutrient uptake and grain quality in Pigeonpea has yet to be thoroughly investigated (De et al., 2025). Comprehending these connections is essential for developing effective and sustainable agricultural techniques. This study was conducted to assess the combined effect of different planting patterns and nutrient management strategies on the growth, yield characteristics, uptake of nutrients and quality of pigeonpea in the agro-climatic conditions of Punjab. The study aims to identify an agronomic strategy that improves productivity while enhancing soil health and sustainability.

Experimental site and weather
 
The entitled study was conducted at agricultural research farm of Lovely Professional University, Phagwara (Punjab) and agricultural farm is situated at a latitude of 31°24’N and a longitude of 75°69’E, with an altitude of 245 m above mean sea level (Fig 1). The region falls within the Trans-Gangetic Plains agroclimatic zone and experiences a semi­arid subtropical climate with hot summers and cold winters. The Meteorological Observatory, Department of Agronomy, Lovely Professional University, provided data on weather parameters, such as temperature (maximum and minimum), relative humidity, wind speed, dew point and rainfallfor two experimentation years (Kharif 2023 to Kharif 2024) as per data shown in Fig 2a and 2b.





Experimental details
 
A field experiment was conducted during the kharif seasons of 2023 and 2024 at Lovely Professional University, Phagwara, Punjab, in a split-plot design with four planting patterns (P₁: 50×25 cm, P₂: 30×25 cm, P₃: Raised bed 67.5 cm apart, P₄: 60×20 cm) as main plots and four nutrient sources (N₁: Control, N₂: RDF, N₃: FYM, N₄: Integrated nutrient management (INM)) as sub-plots which replicated three times. Plot size for the current study was determined to be 6×5 m, or 30 m². Before seed was sown, it was treated with Rhizobium culture. In control plot no fertilizer applied, in case of RDF 15 kg N and 40 kg P₂O₅ supplied through urea and SSP as a basal dose, FYM was applied on the dry weight basis @ 3 t ha^-1 at the time of land preparation and in INM 50% N supplied from RDF and 50% N from FYM.
 
Crop management
 
AL882 variety of Pigeonpea was used for the experiment which is short stature and early maturing variety. The seeds were sownduring 15^th June and 18^th June by dibbling method @ 15 kg ha^-1 after treatment with Rhizobium culture during 2023 and 2024. All the intercultural operations were done as per the package and practices of PAU, Ludhiana for the normal growth of crops. Harvesting of Pigeonpea was done during 5^th November and 8^th November with sickle when the pods fully dried and brownish in colourindicated by a rattling sound when shaken. Harvesting was done manually by cutting the plants with a sickle. After cutting, the plants were left to dry in the field for several days before threshing. Threshing was done by separating the seeds from the pods by beating them with a stick.
 
Data recording
 
Data related to yield attributes were collected following established protocols (Rana and Kumar, 2014; Rana et al., 2014). Following the final harvest, the Pigeonpea crops underwent sun-drying for a few days, after which their weights were recorded to determine the biological yield. Subsequently, the seed yield was documented. The stover yield was calculated by deducting the seed yield from the total biological yield. All recorded yields, including seed, straw and biological yield, were converted into kilograms per hectare (kg ha^-1). Harvest index typically expresses the ratio of economic yield to the above ground biomass and estimated by formula (Donald, 1962). Samples of seeds and stover were collected at harvest from various treatment plots. These samples, pertaining to both seed and stover of pigeonpea, were then subjected to oven drying at 65°C until a consistent dry weight was achieved. Following this, the samples were grounded and utilized for the quantification of nitrogen, phospho­rus and potassium content in both the stover and straw. The processed plant samples should be checked by micro-Kjeldahl’s method to find nitrogen uptake (Jackson, 1973). Wet digestion (di-acid) method was used for the preparation of aliquot to analyze P and K uptake in plant samples. Vando-molybdate yellow colour method was used for the analysis of phosphorous by using spectrophotometer (Jackson, 1973) and flame photometer for the potassium as discussed by Richards (1954). Total nitrogen was taken into consideration for the estimation of crude protein using the standard nitrogen-to-protein conversion factor.Protein yield was then estimated from protein content multiplied by seed yield.Soil microbial population-bacteria, fungi and actinomycetes were estimated by serial dilution and pour plate method suggested by (Waksman, 1922; Alexander, 1977).
 
Statistical analysis
 
To assess the statistical significance of each param­eter, the data were analyzed using analysis of variance (ANOVA). The F-test was used to analyze all the sample data obtained from the two-year experiment, following the approach outlined by (Gomez and Gomez, 1984). The significance of the difference between treatment means was determined using Least Significant Difference (LSD) val­ues at a significance level of p<0.05.

Effect of different planting pattern and nutrient management on seed yield and yield attributes of pigeonpea
 
The yield attributes of Pigeonpea were significantly affected by planting patterns and nutrient management strategies in both years of the study (Table 1). Raised bed planting (P₃) consistently showed the highest pod count plant^-1 (98.85 and 86.47), followed by conventional sowing (P₁) with 97.27 and 84.67 pods plant^-1, however the lowest counts were observed under narrow spacing (P₂) with 82.76 and 70.85 pods plant^-1 in 2023 and 2024, respectively. Likewise, the quantity of seeds pod^-1, pod length and seed index were significantly enhanced in P₃, recording values of 3.81 and 2.72 seeds pod^-1, 5.24 and 4.09 cm in pod length and 10.77 and 8.55 g for seed index during the two years. The enhanced performance of P₃ may be attributed to superior aeration, increased root proliferation and improved resource utilization efficiency linked to raised bed systems. Among the nutrient treatments, Integrated Nutrient Management (N₄) shows a notable enhancement in yield components. N₄ exhibited the highest pod count plant^-1 (106.65 and 93.77), maximum seed count pod^-1 (3.98 and 3.04), greatest pod length (5showsd 4.41 cm) and highest seed index (11.0 and 8.93 g). On the other hand, the control (N₁) demonstrated the lowest values for these characteristics. The enhanced performance under N₄ may result from the synergistic interaction of organic and inorganic nutrition sources, which increases nutrient availability and facilitates improved physiological processes, as noted by Garud et al., 2018. Seed yield was markedly affected by planting patterns and nutrient management (Table 2). P₃ performed better among all other planting configurations, yielding the highest seed output (1188.23 and 1051.04 kg ha^-1), closely followed by P₁. The minimum seed production was recorded in P₂ (968.18 and 825.51 kg ha^-1). N₄ demonstrated superiority among nutritional sources, yielding 1331.75 kg ha^-1 in 2023 and 1125.55 kg ha^-1 in 2024. The control treatment showed the lowest yields (860.4 and 754.77 kg ha^-1). A same trend was noted for stover and biological yields. P₃ produced the maximum stover yield (4961.75 and 4133.35 kg ha^-1), while P₂ provided the minimum (4254.17 and 3244.76 kg ha^-1). The combination of INM (N₄) significantly improved stover yield (5547.42 and 4333.12 kg ha^-1), while the control exhibited the lowest stover production. The biological yield exhibited a similar trend, with highest levels recorded under P₃ (6149.98 and 5184.40 kg ha^-1) and N₄ (6879.17 and 5458.60 kg ha^-1), indicating enhanced biomass accumulation through integrated methodologies. The harvest index (HI), indicative of the efficiency of assimilate allocation to economic yield, was influenced by planting patterns and nutrient treatments. The highest HI was recorded in P₃ (19.32% and 20.21%) and in N₄ (19.47% and 20.68%) in 2023 and 2024, respectively. The lowest values were recorded in P₂ and the control group (N₁). The interaction effect of planting pattern and nutrient management was non-significant for harvest index; however, the overall improvement under P₃ and integrated nutrient management treatments may be due to improved nutrient absorption, superior root development and increased microbial activity in the rhizosphere, promoted by the incorporation of farmyard manure and optimal plant arrangement (Rao et al., 2022; Garud et al., 2018).These findings highlight the necessity of optimizing spatial configuration and nutrient integration to improve yield characteristics and productivity in pigeonpea.





Effect of different planting pattern and nutrient management on nutrient uptake, nutrient content and quality of pigeonpea
 
The concentrations of nitrogen, phosphorus and potassium in the seed and stover of Pigeonpea were considerably influenced by planting pattern and nutrient management during both years, as indicated in Table 3. The highest concentrations of nitrogen (3.15, 3.16%), phosphorus (0.394, 0.491%) and potassium (0.815, 0.824%) in seeds were observed in P₃ throughout planting patterns for 2023 and 2024. The minimum concentrations of nitrogen (2.588, 2.398%), phosphorus (0.309%, 0.409%) and potassium (0.731, 0.748%) were recorded in P₂ for both years. N₄ demonstrated the maximum concentrations of nitrogen (3.228, 3.270%), phosphorus (0.408, 0.508%) and potassium (0.815, 0.841%) in the years 2023 and 2024. The control, without any external nutrition, had the lowest concentrations of nitrogen (2.469, 2.142%), phosphorus (0.310, 0.412%) and potassium (0.719, 0.707%) in seeds for the years 2023 and 2024.


       
A comparable pattern was noted regarding stover content in both years, with P₃ showing the highest levels of nitrogen (1.66, 1.328%), P (0.133, 0.145%) and K (1.362, 1.165%) in stalk. nitrogen, phosphorus and potassium concentrations in Pigeonpea stover are enhanced by N₄, indicating highest levels of nitrogen (1.206, 1.523%), phosphorus (0.133, 0.156%) and potassium (1.376, 1.165%), as presented in Table 4. The interaction effect of planting pattern and nutrient sources was determined to be non-significant for the nitrogen, phosphorus and potassium content in the seeds and stalks of Pigeonpea. The uptake of nitrogen, phosphorus and potassium in both seeds and stalks was significantly influenced by planting patterns and fertiliser management over both years of the study. Table 5 presents data regarding the overall uptake, including both seed and stover uptake. P₃ had the highest nitrogen uptake (96.15 and 108.93 kg ha^-1) for the years 2023 and 2024, respectively. In the same way, regarding phosphorus and potassium uptake (Table 6), the highest phosphorus uptake (11.42, 13.34 kg ha^-1) and potassium uptake (77.54, 68.08 kg ha^-1) was recorded in P₃, while the lowest uptake of nitrogen (72.63, 77.35 kg ha^-1), phosphorus (7.48, 9.02 kg ha^-1) and potassium (63.63, 53.45 kg ha^-1) was observed for both years. The N₄ treatment of the subplot demonstrated the highest absorption of nitrogen (109.92, 128.52 kg ha^-1), phosphorus (12.94, 15.51 kg ha^-1) and potassium (87.25, 75.98 kg ha^-1), whereas the control exhibited the lowest uptake of nitrogen (60.87, 46.15 kg ha^-1), phosphorus (6.52, 6.65 kg ha^-1) and K (56.06, 46.88 kg ha^-1) in the years 2023 and 2024, respectively. The interaction effect of planting pattern and nutrient management sources was significant for total nitrogen and potassium uptake, however the interaction for phosphorus uptake was non-significant in both years. The use of INM demonstrated the maximum nutrient absorption due to the quick availability of nutrients from RDF and the continuous supply of micronutrients from FYM (Rao et al., 2022; Babu et al., 2020). It is clear from the data in Table 7 that nutrition sources and planting pattern had a major impact on protein content. The highest protein content (19.74, 19.80%) in seed was found in P₃ for both 2023 and 2024. P₂ has the lowest protein content (16.17, 14.99%). Regarding nutrient management sources, N₄ had the highest protein level (20.17, 20.43%) in 2023 and 2024, while control had the lowest protein content (15.43, 13.38%). Similarly, in both years, P₃ (237.12, 239.91 kg ha^-1) and N₄ (268.42, 273.75 kg ha^-1) had the highest protein yields. Protein yield and content showed a significant relationship in 2023, while both parameters showed a non-significant interaction in the second year of the trial. The application of INM might have enhanced nitrogen availability and efficiency, which might have accelerated protein synthesis because nitrogen is known to be the basic constituent of proteins (Sarkar et al., 2025; Bansal et al., 2023).








 
Impact of nutrient management and planting patterns on the microbial population
 
Planting patterns and nutrient management sources had a major impact on the microbial population, which includes bacteria, fungus and actinomycetes (Table 8). P₃ had the highest number of bacteria (60.62, 60.84), fungi (14.75, 14.84) and actinomycetes (25.16, 25.34) among the planting patterns. P₂ (30 × 25 cm) had the lowest number of bacteria (50.65, 50.95), fungi (9.31, 9.58) and actinomycetes (21.07, 21.20) during the two study years. Similarly, subplot N₄ had the highest counts of bacteria (52.48, 64.81), fungi (14.59, 15.21) and actinomycetes (26.97, 27.60) in 2023 and 2024, while control, or no external nutrient application, had the lowest counts of bacteria (47.98, 43.79), fungi (7.91, 7.43) and actinomycetes (19.26, 18.14). With the exception of fungus, which showed non-significant interaction in 2023, interaction between bacteria, fungi and actinomycetes was found to be substantial in both years. Additionally, the addition of FYM would have enhanced nutrient availability, nodulation and root growth by boosting rhizosphere microbial activity (Sarkar et al., 2025; Dash et al., 2024). The similar results found by Bhardwaj et al. (2023); Venkatesh et al. (2023) in their studies on nutrient management in pigeon pea based intercropping system.

This study revealed that planting pattern and nutrient management significantly affect the growth, production, nutrient uptake and quality of Pigeonpea. The combination of raised bed planting (P₃) and Integrated Nutrient Management (N₄) consistently performed better than other treatments by improving yield characteristics, seed and stalk yield, biological yield and nutrient use efficiency throughout both years of the trial. This combination resulted in enhanced protein content and microbial populations, signifying beneficial effects on soil biological health. The exceptional performance of INM is due to the synergistic effect of a balanced nutrient supply from both organic (FYM) and inorganic sources (RDF), which provided continuous nutrient availability and enhanced microbial activity. Raised bed planting improved soil aeration, root development and moisture retention, therefore increasing the utilization of nutrients and crop yield. These findings highlight the possibility of combining raised bed planting with integrated nutrient management as a sustainable agricultural method to improve Pigeonpea yield and maintain soil fertility under agro-climatic conditions of Punjab.

The present study was supported by Lovely Professional University, Phagwara, Punjab.
 
Disclaimers
 
The views and conclusions presented in this article, “A Sustainable Approach Towards Pigeonpea Production: Effects of Planting Pattern and Nutrients Supply on Yield, Uptake and Nutritional Quality,” are solely those of the authors and do not necessarily reflect the views or policies of their affiliated institutions or funding bodies. The authors are responsible for the accuracy, analysis and interpretation of the information provided. However, they assume no liability for any direct, indirect, incidental, or consequential losses or damages that may arise from the use, application, or interpretation of the content presented in this study.
 
Informed consent
 
This study was truly based on crop research only. 

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.