Soil fertilization affects the abundance and distribution of carbon and nitrogen cycling genes in the maize rhizosphere
Abstract Soil microbes performs important functions in nitrogen and carbon cycling in the biosphere. Microbial communities in the rhizosphere enhance plants’ health and promote nutrient turnover and cycling in the soil. In this experimental study, we evaluated the fundamental effects of soil fertilization with organic (compost manure) and inorganic fertilizer on the abundances and distribution of carbon and nitrogen cycling genes within the rhizospheric regions of maize plants. Our result showed that maize plants through rhizosphere effects selected and enriched the same functional genes glnA, gltB, gudB involved in nitrogen cycle as do higher compost and lower inorganic fertilizer treatments. This observation was significantly different from those of higher doses of inorganic fertilizer and lower compost manure treated soil. Only alpha amylase encoding genes were selectively enriched by lower compost and higher inorganic fertilized soil. The other treatments only selected peculiar carbon cycling genes in the rhizosphere of maize. Also Actinomycetales are selected by high compost, low inorganic fertilizer and control while Bacillales are promoted by low compost and higher inorganic fertilizer and this indicated that only microbes capable of tolerating the stress of higher dose of inorganic fertilizer will thrive under such condition. Therefore, soil fertilization lower nitrogen gas emission but increases carbon dioxide evolution in the agricultural soil.