Shifts in microbial community structure
The PCA was applied to nmol g−1 soil DW values for individual PLFAs of soil samples derived from different treatments at different sampling dates(Fig. 1). The component weights were plotted for the first two variables. The first principal component (PC 1) accounted for 59.9% of the variation, and the second principal component (PC 2) accounted for 14.0% of the variation. Differences were found between samples at the vegetative (tillering) and reproductive stage (grain-filling and maturity stages) (Fig. 1a).