Soil microbial properties influenced with long term application of manures and fertilizers

Abstract

An ongoing long-term field experiment established in 1995 at CCS Haryana Agricultural University, Hisar (India) under pearl millet-wheat cropping system was selected to examine the impact of organic manures and fertilizers on soil microbiological properties. After 19 years of experiment, the samples were collected after wheat harvest in April, 2014. Under different combinations of treatments, the microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) content in soil ranged from 202–491 and 35.0–79.8 mg/kg, respectively. The lower content of MBC and MBN was observed in farmyard manure (FYM) treated plots as compared to pressmud or poultry manure. Soil microbial quotient (SMQ) ranged from 3.18– 5.61% and higher SMQ was observed with pressmud and poultry manure application as compared to FYM application. The highest dehydrogenase activity (DHA) was reported with FYM15 (63.71 μgTPF/g/24 hr) which was statistically at par with FYM15N150 (59.75 μg TPF/g/24 h) and pressmud7.5 (58.14 μg TPF/g/24 h). Among organic manures applied alone alkaline phosphatase activity (APA) followed the order: poultry manure>FYM>pressmud. The highest urease activity (97.6 μg NH4 +-N/g/h) was observed with pressmud7.5 and this may be attributed to higher N content (3.23%) in pressmud. The dehydrogenase and urease activity decreased in the plots where organic manures were applied in conjunction with NP fertilizers as compared to solitary application of organic manures. However, reverse trend was observed in case of alkaline phosphatase. Overall, pressmud applications exhibited favorable impacts on soil properties under pearl millet wheat cropping. Therefore, continuous application of pressmud could lead to long term maintenance of soil microbial properties in these sandy loam soils.

Long-term application of organic manures and chemical fertilizers improve the organic carbon and microbiological properties of soil under pearl millet-wheat cropping system in North-Western India

“…The FYM receiving treatments recorded the higher MBC content as compared to PRM and POM. This could be due to the large amount of SOM added through FYM as compared to POM or PRM [ 56 ]. Higher value of labile C/DOC in soil dressed with FYM led to greater plant growth, root biomass, enhanced root exudation, increased microbial activity.…”

“…Among various treatments, the plots receiving PRM coupled with NP fertilizers showed the highest (69.54 μg NH4 + g −1 hr −1 ) urease activity because of more N percentage in PRM ( Table 1 ). Pressmud is a by-product of sugarcane and is rich in nitrogen due to sugarcane being a high N feeding crop, which could lead to enhanced urease activity in PRM-treated plots [ 56 ]. The greater urease activity might be expected due to accrued SOC content ( Table 2 ) in soil that increased microbial population and MBC ( Fig.…”

Soil biological indicators associated with nitrogen mineralization patterns in rice soils under long‐term integrated nutrient management

“…The increase in urease activity in organically amended plots are related to an increase in the population of efficient soil microbes which can release extracellular enzymes, besides a higher concentration of N in soils stimulates urease activity in soil amended with different organic inputs (Sheoran et al, 2020). Chitin degradation depends heavily on soil β-1, 4-NAG enzyme.…”