Impact of Nano-Nutrient Application on Soil Microbial Biomass and Enzyme Activity in Wheat-Based Cropping Systems
Avinash Kumar Rai
Krishi Vigyan Kendra, Sonbhadra, Uttar Pradesh, India and Directorate of Extension, Aacharya Narendra Dev University of Agriculture & Technology, Kumarganj, Ayodhya, Uttar Pradesh, India.
Uma Sharma *
College of Biotechnology, DUVASU, Mathura, Uttar Pradesh, India.
Sumit Raj
Department of Soil Conservation and Water Management, CSAUA&T Kanpur-02, India.
Chetna Khokhar
Department of Chemistry, Om Sterling Global University, Hisar, India.
Ravi
CCSHAU, Hisar, Haryana, India.
Sulochna
Faculty of Agriculture, Department of Agronomy, Agriculture College Garhwa Bishunpur, Piprakala, Garhwa-822114, Birsa Agricultural University, Jharkhand, India.
Narinder Panotra
Institute of Biotechnology, SKUAST Jammu, India.
Ajeet Singh
Department of Agronomy, Janta Vedic College Baraut (Baghpat), India.
*Author to whom correspondence should be addressed.
Abstract
Sustainable integrated nutrient management addresses soil degradation and fertilizer inefficiency by combining nano-nutrients, organic manure, and bio-inoculants. The field experiment was conducted during the 2024 rabi season at KVK, Ghazipur, using a randomized block design with nine treatments and three replications. Wheat variety DBW-187 was cultivated with a standard RDF of 150:60:40 kg ha⁻¹. Treatments integrated conventional fertilizers with farmyard manure (5 t ha⁻¹), NPK consortia seed treatments, and foliar-applied nano-urea (4% w/v). Post-harvest soil samples from 0–15 cm depth were analyzed for microbial biomass carbon using chloroform fumigation-extraction, while dehydrogenase, alkaline phosphatase, and urease activities were estimated via standard colourimetric and quantification methods. Integrated nutrient management significantly enhanced wheat productivity and soil biological health, following the hierarchy T4 > T6 > T5 > T7 > T9 > T8 > T2 > T3 > T1. Treatment T4 (100% RDF + FYM) achieved the highest grain yield (6.20 t/ha), microbial biomass carbon (342.6 mg/kg), and enzymatic activities. Notably, T6 (100% RDF + Nano-Urea) outperformed conventional RDF (T2), yielding 5.72 t/ha and 315.7 mg/kg SMBC. This superiority stems from the higher efficiency of nano-fertilisers and the carbon-rich substrate provided by FYM, which stimulated bacterial (32.5times 106 CFU/g) and fungal (16.4 times 104 CFU/g) proliferation. Integrating nano-urea with organic manure and bio-inoculants significantly boosts wheat yields and soil health. The combination of RDF and FYM (T4) optimises microbial activity and productivity.
Keywords: Wheat productivity, nano-urea, soil health, microbial biomass carbon, enzymatic activity, integrated nutrient management, Indo-Gangetic plains.