Fig 4.

Detrended correspondence analysis (DCA; eigenvalue of first axis = 0.53, second axis = 0.21) of the soil AM fungal communities obtained in this study represented by DNA, together with season (seasonal variation in AM fungal communities at one field site, where soil was derived for this study), obtained during five field sampling events over 3 years, and 15 fields (variation of maize root AM fungal communities across 15 different agricultural fields sampled in September 2007) (data from reference 57). AM fungal community composition was assessed using T-RFLP for all data points. Note that the different maize varieties of the greenhouse study represent average communities of soil samples of three replicate plants (to accommodate comparison to pooled samples); season and 15 fields are pooled root samples of six plants. Three- to four-month-old maize roots were collected for 15 fields, while maize roots for season had variable age (from 2 to 4 months).