A planter is provided with onboard seed treatment for treating seeds on the goduring row-crop planting of an agricultural field. The seed treatment systemof the planterallows for selective planting of specific zones of a field with treated seed,which mayinclude planting different zones of the field with seeds having differenttreatments. Theplanter may store untreated seed in bulk and include a seed treatment systemthatselectively and precisely treat the untreated seeds during treatment events byway of aninjection or spray nozzle system that applies liquid treatment to the seedstraveling alonga tightly defined travel path, such as within pockets of a belt that carriesthe seedsthrough a seed tube.
