Indian Journal of Agronomy

A field experiment was conducted at ICAR-Indian Agricultural Research Institute, New Delhi during rainy season of 2013–14 and 2014–15 in sandy clay loam soil to verify and validate the contribution of 2 microbial inoculations and zinc (Zn) fertilization on growth, yield and economics of rice (Oryza sativa L.). Rice variety ‘Pusa Sugandh 5’ was grown under 3 methods of cultivation, viz. puddled transplanted rice (PTR), system of rice intensification (SRI) and aerobic rice system (ARS) and 4 nutrient management options, viz. recommended dose of nutrients (RDN) (N₁₂₀P_25.8), 75% RDN, 75% RDN + Anabaena sp. (CR1) + Providencia sp. (PR3) and 75% RDN + Anabaena-Pseudomonas (An-Ps) biofilmed formulation with and without Zn (5 kg Zn/ha through ZnSO₄.7 H₂O). Thus making total eight nutrient management options along with one absolute control (N₀P₀Zn₀). Results of 2 year study revealed that, microbial inoculation of An-Ps biofilmed formulation with 75% RDN increased number of tillers/m² by 16 and 13 with Zn and by 12 and 10 without Zn in first and second year, respectively. Increase in shoot dry matter due to CR1 + PR3 consortia with 75% RDN was 40.6 and 36.3 g/m² with and without Zn in first and 31.4 and 28.6 g/m² with and without Zn in second year, respectively. Contribution of microbial inoculation of An-Ps biofilmed formulation to increasing grain yield was 0.29 and 0.30 t/ha with and without Zn and same for CR1 + PR3 consortia was 0.28 and 0.30 t/ha with and without Zn, respectively. Aerobic method saved 6, 000 and 9, 640 /ha as compared to PTR, while SRI saved 3, 440 and 5, 800 /ha as compared to PTR in first and second year, respectively. Contribution of microbial inoculation of An-Ps biofilmed formulation in increasing net returns was 7, 500 and 7, 670 /ha with and without Zn and same for CR1 + PR3 consortia was 7, 350 and 7, 660 /ha with and without Zn, respectively.