Impact of Crop Residue Incorporation and Incubation Period on DTPA-Extractable Micronutrient Cations

Abstract

ABSTRACT Micronutrient deficiency is a major problem in sustainable crop production due to the intensive cropping. Excessive application of chemical fertilizers often results in poor soil physical properties and microbial population resulting in adverse effects on soil fertility and productivity. Therefore, crop residue incorporation as organic manure is gaining interest among growers. The assessment of nutrient release from various crop residues in soil at different intervals will help to formulate the rates and frequency of these residue applications. Therefore, a lab study was carried out to evaluate the impact of crop residue incorporated on micronutrient content in soil i.e., zinc (Zn), manganese (Mn), iron (Fe), and copper (Cu) at different incubation periods. In this study, 11 crop residues including biomass of eight field crop residues (Lens culinaris, Avena sativa, Zea mays, Oryza sativa, Saccharum officinarum, Triticum aestivum, Brassica juncea, and Hordeum vulgarae) and leaves of three tree species (Melia azedarach, Azadirachita indica, and Populus alba) were selected to study their effect on diethylene triamine pentaacetic acid (DTPA-extractable) micronutrient cations over a 63 days period in a sandy loam soil. Results of study revealed that DTPA-extractable micronutrient cations substantially enhanced after addition of different crop residues over the control treatment. The DTPA-extractable micronutrients were generally higher at 14th days after incorporation. Among crop residue treatments, the incorporation of M. azedarach residue resulted in higher content for micronutrients.