Growth, Development, and Productivity of Maize (Zea mays L.)–Soybean (Glycine max (L.) Merr.) Intercropping under Different Planting Patterns and Ghanjivamrit Application Rates

A field experiment was conducted during the 2020 kharif season at CSK Himachal Pradesh Krishi Vishvavidyalaya, Palampur, India, to evaluate four planting patterns and four ghanjivamrit application rates (0, 500, 1000, and 1500 kg ha−1) in a maize–soybean intercrop. The treatments were arranged in a split-plot design with three replications. Plant height, dry matter accumulation, maize leaf area index, soybean nodule mass, crop phenology, and maize grain-equivalent yield were assessed. Furrows after every two maize rows produced the highest reported marginal maize grain-equivalent yield (6038.9 kg ha−1), compared with 4759.6 kg ha−1 under flat-bed planting. Across amendment rates, the highest marginal equivalent yield was observed at 1500 kg ha−1 (6184.0 kg ha−1), compared with 4399.6 kg ha−1 without ghanjivamrit. Planting pattern and amendment rate were associated with differences in several maize and soybean growth measurements, including soybean nodule mass; an interaction was reported for maize dry matter at 30 days after sowing. Neither factor significantly affected the recorded phenological endpoints. The results identify promising treatment levels under the tested soil and seasonal conditions but do not establish a unique optimal treatment combination or long-term effects.