Long-Term Organic Manure Application Alters Urease Activity and Ureolytic Microflora Structure in Agricultural Soils

Abstract

Ureolytic microbes in soil produce urease to catalyze the hydrolysis of urea to NH3/NH4+. Manure is widely applied in agriculture and has the potential to influence soil urease activity. In this study, we examined the responses of the ureolytic microbial community to manure application in two agricultural soils from north (N) and south (S) China using high-throughput sequencing of the ureC genes. We found that N soil and S soil harbored significantly distinct ureolytic communities, as no OTU was shared between two locations. The slight variation of the ureolytic community (32.2%, Adonis) was observed in N soil where low rates of manure were applied. However, dramatic alteration of the structure of ureolytic community (83.4%, Adonis) was found, possibly by promoting the growth of Betaproteobacteria and Deltaproteobacteria and the suppression of the growth of Actinobacteria in S soil where high rates of manure were inputted. The total C and C/N ratio were the main environmental factors driving the microbial communities. The relative ratios of ureC to 16S rRNA genes ranged from 1.5 to 3.5% among the two soils. The abundance of ureC genes was significantly and positively correlated with total phosphorus (TP, r = 0.87, p < 0.001). Positive correlations between the urease activity and soil available NH4+ (r = 0.81, p = 0.001), TP (r = 0.84, p = 0.001), and the abundance of ureC (r = 0.87, p < 0.001) were observed in our study. We speculate that sufficient soil phosphorus promotes the growth of ureolytic microbes, which results in higher urease activity and the greater release of available NH4+.

Predicting genomic traits in ammonia-oxidizing archaea using phylogenetic signals

“…Resource rich sites with high amounts of total nitrogen and ammonium as well as soil organic carbon, located in areas with higher organic N addition [22], were related to the dominance of AOA with predicted potential for ureolytic metabolism ( ureC ). Nitrogen addition may increase the abundance of ureC genes [64], which in turn is associated with high amounts of ammonium as a result of urea hydrolysis [65]. Higher potential ammonia oxidation activity was linked to taxa with the low affinity ammonium transporter, likely because the high ammonium concentrations used in the activity assay favored the ammonia oxidizers with low ammonia affinity or those that prefer inorganic to organic N sources, including ammonia-oxidizing bacteria [66].…”

“…The hits falling together with Nitrosocosmicus taxa in the phylogeny were assigned the low affinity transporter type (Amt1), as all sequenced Nitrosocosmicus taxa encode uniquely one low affinity Amt [35][36][37][38]. It should be noted here that other studies have used the reverse nomenclature, in which Amt1 and Amt2 are defined as high and low affinity transporters, respectively [39][40][41]. To clarify these inconsistencies in the nomenclature, we screened the Amt hits of our study for the primers used by Nakagawa and Stahl [33] for both types of transporters, and found that the amt2 primers from Nakagawa and Stahl [33] matched the genes that were defined as amt1 in Offre et al [39] and vice-versa.…”

Nitrogen Cycle in Farming Systems

“…The N min release rate is strongly dependent on both the biodegrability of N org and environmental factors affecting microbial activity. These issues are discussed in detail in this section [11][12][13].…”

“…Secondly, there are microorganisms in the soil that contain the enzyme urease (ureolytic bacteria). This issue has been further investigated in China by examining the activity, abundance, and genetic diversity of soil ureolytic bacteria [12]. The study was carried out in two contrasting climatic zones (temperate-North China; tropical-South China), differing in soil type (Udic Mollisols and Agri-Udic Ferrosol, respectively).…”

Efeitos da compostagem termofílica industrial na qualidade do lodo de esgoto e na dissipação de resistência antimicrobiana em solos

“…Isto é esperado visto que a variação de UA encontrada em solos é atribuída principalmente à quantidade e forma da matéria orgânica presente e, sabe-se que resíduos a base de lodo de esgoto contribuem diretamente para seus aumentos (i.e. da matéria orgânica e atividade enzimática) (Frankenberger et al, 1983;Igalavithana et al, 2017;Wolna-Maruwka et al, 2018;Dhanker et al, 2021;Wang & Xiong, 2022;Myszura-Dymek & Żukowska, 2023).…”