Fertilización del kiwi (Actinidia deliciosa (A. Chev.) C. F. Liang & A. R. Ferguson, cv. Hayward) durante la etapa de implantación en el sudeste bonaerense (Argentina)

the effects of nitrogen and potassium fertilization on kiwifruit plant growth during plant establishment (season 2008 - 2009) were assessed at an orchard placed in balcarce (buenos aires. province, argentina). the following fertilization treatments were applied: t: control without fertilization, n: nitrogen (48 kg/ha n), k: potassium (60 kg/ha k), and nk: nitrogen and potassium (48 kg/ha n - 60 kg/ha k respectively). stem and top internode length, and leaf area were sampled at regular intervals. stem diameter was assessed at the end of season, and roots arrangement in the soil profile was measured during rest. leaf macronutrient content, soil mineral n, anaerobic n (nan), and organic c (co) were also analyzed. soil was classified as argiudol; the levels of nan were between 85 - 100 mg/kg and levels of co were 45 - 50 g/kg, in the first 30 cm. our results concerning shoot growth do not support the need to apply either nitrogen or potassium fertilizers under our experimental conditions. leaf nitrogen and potassium contents were maintained within normal standards in all treatments including the control. root system, as observed through the rest period, benefited from the nitrogen fertilization. within the 10-20 cm soil layer, an average of 61 roots/cm2 were found in n, while lower values were recorded in the other treatments: 40 roots/cm2 in nk, 28 roots/cm2 in k, and 19 roots/cm2 in the control.