1. São Paulo State Univ. (UNESP)College of Agricultural SciencesBotucatuSão PauloBrazil
2. Netherlands Institute of EcologyDep. of Microbial Ecology6708 PBWageningenNetherlands
3. São Paulo State Univ. (UNESP)College of Agricultural Sciences, Dep. of Crop ScienceAv. Universitária 3780, Lageado Experimental Farm, 18610‐034BotucatuSão PauloBrazil
4. Purdue Univ.Agronomy Dep.West LafayetteINUnited States
5. Federal Univ. of Goias (UFG)Agronomy Dep.JataíGoiásBrazil
6. Agronomic Institute of Campinas (IAC)Soils and Environmental Resources CenterCampinasSão PauloBrazil