Seasonal Uptake and Partitioning of Macro- and Micronutrients in Yellow-Fleshed Kiwifruit (Actinidia chinensis var. chinensis)

Little information is available on the yellow-fleshed Zespri Zesy002 kiwifruit dynamic of mineral nutrient uptake and partitioning within organs. The aim of the present experiment was to find nutrient requirements and supply data for a specific nutrient management plan for Zesy002. The trial was conducted, for three years, in northern Italy, on a six-year-old kiwifruit orchard of the variety Zespri Zesy002. During the experiment organs were periodically sampled and analyzed for macro- and micronutrient concentration. A yearly nutrient uptake of 175 g N plant-1, 16 g P plant-1, 138 g K plant-1, 235 g Ca plant-1, 48 g Mg plant-1, 17 g S plant-1, 247 mg B plant-1, 673 mg Cu plant-1, 5.20 g Fe plant-1, 473 mg Mn plant-1, and 263 mg Zn plant-1 was calculated, confirming that kiwifruit is a high-nutrient-demanding species. The nutrients found in the tree organs were divided in two factions: removed (not returned into the soil) and recycled (returned into the soil during and at the end of the growing cycle). The two fractions were similar for N, P, K, S, and Mn. The fraction recycled of Ca, Mg, Cu, and Zn was higher than the fraction removed, and the reverse was observed for Fe. These data created the basis for the determination of the correct nutritional plans that take into consideration not only nutrient requirements but also the dynamics of uptake during the season.