Influence of early plant defoliation and nitrogen fertilization on the productivity of seed potatoes grown on light soils in the Plaskowyz Kolbuszowski

abonos nitrogenados air temperature aphididae application rates control de plagas crop yield cultural methods defoliation dose d'application field experimentation lluvia lutte antiravageur mode de culture nitrogen fertilizers papa de siembra pest control plant de pomme de terre plant response pluie pregermination rain rendement des cultures rendimiento de cultivos respuesta de la planta sandy soils seed potatoes selection sol sableux solanum tuberosum statistical methods suelo arenoso temperatura del aire tubercule tubers variedades varieties weather