Main content area

Integrated phosphorus management in maize–chickpea cropping system on alkaline Fluvisol

Venkatesh, M. S., Hazra, K. K., Ghosh, P. K., Singh, Mohan
Nutrient cycling in agroecosystems 2019 v.113 no.2 pp. 141-156
Fluvisols, agroecosystems, alkaline phosphatase, alkaline soils, animal manures, bacteria, chickpeas, corn, crop production, crop rotation, fertilizer application, field experimentation, microbial carbon, nutrient use efficiency, phosphates, phosphorus, phosphorus pentoxide, seed treatment, soil biological properties, soil microorganisms, soil pH, solubilization
In tropical agro-ecosystem, crop production is constrained by the reduced availability of soil phosphorus (P) due to strong P fixation. A field experiment was conducted for five cropping seasons on an alkaline Fluvisol to assess the integrated effect of six system-based fertilizer P rate (kg P₂O₅ ha⁻¹) in maize (M)–chickpea (C) rotation [M₀–C₀, M₀–C₄₀, M₃₀–C₀, M₃₀–C₄₀, M₆₀–C₀, M₆₀–C₄₀], two manure treatments [no farmyard manure (FYM), FYM at 5 t ha⁻¹], and two phosphate solubilizing bacteria (PSB) treatments [no PSB, PSB seed treatment in chickpea] on soil available-P, soil–plant P dynamics, balance, P use efficiency, and system productivity. Combined application of fertilizer P and FYM had a strong positive impact on soil available-P, soil biochemical properties, P acquisition and crop productivity. Conversely, the effect of PSB was marginal. Treatment M₆₀–C₄₀ + FYM + PSB increased soil available-P by 56% at the end of 5-year rotation; where 53% depletion was noticed in treatment M₀–C₀ − FYM − PSB (control). Treatments M₃₀–C₄₀ + FYM ± PSB, M₆₀–C₀ + FYM ± PSB, and M₆₀–C₄₀ + FYM ± PSB had a positive trend of soil available-P. The order of fertilizer P treatments for P uptake and annual P balance was M₆₀–C₄₀ > M₃₀–C₄₀ > M₆₀–C₀ > M₀–C₄₀ > M₃₀–C₀ > M₀–C₀. FYM application improved P recovery efficiency by 71%. Soil microbial biomass carbon, dehydrogenase and alkaline phosphatase, and soil pH had significant relationship with available-P (p < 0.01). Notably, treatments M₃₀–C₀ + FYM + PSB and M₆₀–C₄₀ − FYM − PSB had a similar effect on maize productivity (4.1–4.2 t ha⁻¹). Likewise, treatments M₆₀–C₀ + FYM + PSB and M₆₀–C₄₀ − FYM − PSB were comparable for chickpea productivity (p > 0.05). Therefore, integration of manure and fertilizer P is recommended for increasing the productivity and P use efficiency in maize–chickpea rotation in tropical alkaline soil.