Optimizing phosphorus management in wheat-based intercropping systems for enhanced productivity, profitability, energy efficiency, and soil health in Indian Inceptisols

Phosphorus deficiency in Indian Inceptisols limits crop production due to high fixation, low availability and poor fertilizer use efficiency. Even with recommended fertilizer dose, much of the applied P becomes unavailable, make strategies that enhance its solubility, recycling and plant uptakes are essential. Wheat-mustard intercropping systems improves P use efficiency through complementary root distribution and enhanced biological activity while phosphorus solubilizing bacteria (PSB), rock phosphate and organic manure further increase P availability and soil health. Therefore, a two-year factorial randomized block design field experiment was conducted with four wheat-based intercropping systems and six phosphorus management practices. The results showed significant improvements in mustard and wheat equivalent yield (MEY/WEY); CS 3 and CS 4 showed 29.6–34.8% enhancements over CS 2 , with CS 4 slightly superior, while CS 3 and CS 4 show strong profitability (40–60% higher net returns), with CS 3 being slightly superior. Among P management strategies, P 5 produced the highest MEY/WEY (34.3–34.6%) and profitability (≈45–48% higher net returns; 18–20% higher B:C), energy output (28–35%) and energy productivity (9.5%) enhancement under P₅ over P 1 . The CS 4 system recorded the highest soluble P (7.91 mg kg −1 ), organic P (358.4 mg kg −1 ) and total P (790.4 mg kg −1 ), corresponding to increases of 24.7, 51.4, and 7.2% over CS 1 . Microbial P treatments (P₅/P₃) further enhanced P pools, such as soluble P (48.1%), Fe-bound P (29.2%), Ca-bound P (41.1%) and total inorganic P (33.9%) over P₁. The CS 4 system reduced bulk density (5.2%), increased soil organic carbon (13.9%), available N (10.6%), P (24.1%) and K (6.3%), along with higher microbial activity and micronutrient availability. Thus, integrating Wheat + mustard (5:2) and 75% RDP + PROM + PSB is recommended, as a productive, energy-efficient and soil-enriching strategy for profitable wheat-based system in P-deficient Inceptisols.