Contrasting effects of glucose, living roots and maize straw on microbial growth kinetics and substrate availability in soil

The most modern molecular approaches fail to link structure of soil microbial community with its functions. We used classical physiological approaches based on microbial growth kinetics and microbial affinity to the substrate to show the shift in functional properties of the soil microbial community after amendments with substrates of contrasting availability. Kinetic parameters of substrate-induced respiration and substrate availability in soil were monitored during the growth of maize, and decomposition of glucose or maize straw. Input of small amounts of easily available substrates (i.e. glucose or root exudates) significantly increased the specific growth rates of soil microorganisms by up to 13 and 20%, respectively...