Differences in the abundance of N cycling genes in the rhizosphere and bulk soil.

<p>The numbers in brackets indicate the percentage difference of a functional gene signal intensity between rhizosphere and bulk soil samples relative to the normalized signal intensity in the bulk soil sample. The gray-colored genes were not detected by GeoChip 3.0. *p<i><</i>0.05, and **p<i><</i>0.01.