Contribution of microbial inoculation and zinc-fertilization to growth and yield of rice (Oryza sativa) under different cultivation methods in a sub-tropical and semi-arid type climate

Abstract

A field experiment was conducted at ICAR-Indian Agricultural Research Institute, New Delhi during rainy sea- son of 201314 and 201415 in sandy clay loam soil to verify and validate the contribution of 2 microbial inocula- tions 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 intensi- fication (SRI) and aerobic rice system (ARS) and 4 nutrient management options, viz. recommended dose of nutri- ents (RDN) (N P ), 75% RDN, 75% RDN + Anabaena sp. (CR1) + Providencia sp. (PR3) and 75% RDN + Ana- 120 25.8 baena- Pseudomonas (An-Ps) biofilmed formulation with and without Zn (5 kg Zn/ha through ZnSO .7 H O). Thus 4 2 making total eight nutrient management options along with one absolute control (N P Zn ). Results of 2 year 0 0 0 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.