Reaction of the main corn hybrids on the sowing period, the density and fertilizers applied under conditions of soils with various podzolization degree in the central zone of the western plain

application rates binage cava control de malezas dose d'application ensemencement environmental temperature espacement espaciamiento fertilisation fertilizer application herbicidas herbicide herbicides hoeing lluvia lutte anti-mauvaise herbe pluie podzol podzoles podzols rain siembra sowing spacing timing weed control zea mays