Agronomic Biofortification In Rice Greengram Cropping System Under Varying Levels Of Nitrogen And Zinc In Alfisols

Abstract

Four field trials were conducted during the wet (kharif) and summer seasons of newline2021 22 and 2022 23 at the Agricultural Research Station, Binjhagiri, Chhatabar, under newlinethe Faculty of Agricultural Sciences (IAS) , Siksha O Anusandhan (Deemed to be newlineUniversity) (SOADU), Bhubaneswar. The soil type was a well-drained sandy loam with newlinea pH (5.71), low in organic carbon (0.43 %) and available nitrogen (208 kg ha-1), medium newlineavailable phosphorus (21.3 kg ha-1) and potassium (128 kg ha-1), and low in available zinc newline(0.41 mg kg-1) . The primary objective was to assess the direct and residual effects of newlinenitrogen management and agronomic zinc biofortification on growth, yield, nutrient content newlineand uptake, quality and economic returns in a rice-greengram cropping sequence. The newlineexperimental layout in a split-plot design with four nitrogen management strategies newline(N1: 75% Recommended dose of Nitrogen (RDN), N2: 100 % RDN, N3: 75% RDN + 25% newlineN through FYM and N4: 125% RDN) in the main plots and four zinc Biofortification newlinetreatments (Z0: No Zinc control, Z1: Zn 5kg ha-1 soil application, Z2: Zn 2.5 kg ha-1 soil newlineapplication + ZnSO4 0.5% one spray at active tillering and Z3: Zn 2.5 kg ha-1 soil newlineapplication + ZnSO4 0.5% three sprays at active tillering, PI and heading stage) in the newlinesubplots and replicated thrice. The recommended fertilizer dose (RDF) was 80:40:40 kg newlineN:Pand#8322;Oand#8325;: Kand#8322;O haand#8315;¹ and the recommended nitrogen dose (RDN) at 100 kg N haand#8315;¹. Among newlinethe nitrogen management practices, the N3 treatment (75% RDN + 25% N from FYM) was newlinesignificantly superior to all N combinations. This treatment recorded significantly higher newlinetiller counts, more dry matter accumulation and effective tillers per square meter (337.7), newlinelonger panicles (26.4 cm), higher 1000 grain weight (23.2 g), higher fertile grains panicle- newline1(143.2 grains), fewer chaffs per panicle (12.2), and the highest grain yield (5335 kg haand#8315;¹). newlineIt also recorded minimum pest and disease incidence, higher nutrient content in grains with newlinemaximum nutrient uptake, higher microbial pop