1Scientist, Rajmata Vijyaraje Scindia Krishi Vishva Vidhyalaya, Gwalior, Madhya Pradesh-474 002
2ADG, (HRM), Krishi Anusandhan Bhawan II, Indian Council of Agricultural Research, Pusa, New Delhi, 110 012
3Principal Scientist, Division of Agronomy, ICAR-Indian Agricultural Research Institute, New Delhi, 110 012
4Scienitst (Agronomy), Central Soil Salinity Research Institute, Karnal, Haryana, 132 001
5ARS Scientist (Agronomy), ICAR Indian Institute of Soil and Water Conservation, Vasad Anand, Gujarat, 388 306
6Principal Scientist, ICAR-Indian Institute of Soil and Water Conservation, Dehradun, Uttarakhand, 248 195
7Scientist, ICAR- Indian Grassland and Fodder Research Institute, Jhansi, Uttar Pradesh, 284 003
8Assistant Professor, Swami Keshwanand Rajasthan Agriculture University, ARS, Sri Ganganagar, Rajasthan-335 001
ICAR-Indian Agricultural Research Institute, New Delhi-110 012
*Corresponding author's Email: joshi.ekta86@gmail.com
Online published on 16 October, 2021.
A 2-year (2013 and 2014) field study was carried out at the ICAR-Indian Agricultural Research Institute, New Delhi, to access the effects of omitted nutrients on soil microbial biomass carbon (MBC), enzyme activity, the relationships among these parameters in maize-wheat cropping system and to validate the soil-test-crop response (STCR)-based fertilizer application for targeted yield (5.0 t/ha) of wheat ‘HD 2967’ and maize ‘PEHM 5’ each in maize (Zea mays L.)–wheat (Triticum aestivum L.) cropping system. The experiment comprising 15 treatments involving application of N (–PKZn), NP (–KZn), NPK (–Zn) and NPZn (–K) to both maize and wheat crops, to maize (omitted in wheat) and to wheat (omitted in maize) crop only, absolute control (no nutrient applied), recommended rate of nutrients (RDN) (150-60-40-5.5 kg/ha N-P-K-Zn) and STCR-based application of nutrients (200-75-65-4 kg/ha N-P-K-Zn). The fixed plots experiment was carried out in a 3-time replicated randomized complete block design. The dehydrogenase, alkaline phosphatase and urease enzyme activities in soil and MBC were significantly higher with STCR approach-based NPKZn application than the others for targeted yield of 5 t/ha of both maize and wheat crops. The continuous omission of N, P, K and Zn in a cropping system during both the study years reduced MBC by 51.9, 7.6, 12.7, 6.5% respectively. The recommended dose of NPKZn resulted in higher activity of dehydrogenase, urease and alkaline phosphatase enzyme than N, NP, NPK, NPZn treatments and absolute control. The continuous omission of N, P, K and Zn in a cropping system significantly reduced the soil enzymes activity in maize–wheat cropping system.
Enzymatic activity, Fertilization, Maize, Microbial biomass carbon, Soil test crop response approach, Wheat
