Potassium chloride fertilization of potatoes: nutrient uptake rate and tuber yield of cultivars Ágata and Atlantic

Adubação em batata com cloreto de potássio: taxa de absorção de nutrientes e produtividade de tubérculos de Ágata e Atlantic

ABSTRACT

Potassium (K) is the nutrient taken up in the greatest quantity by the potato plant. Obtaining information about the relationship between tuber yield and K application rate allows improvements in fertilizer use efficiency. We aimed to evaluate the variation in potassium fertilizer doses in uptake rate of other nutrients and in potato tuber yield. The experiments were carried out in Unaí-MG testing cultivars Ágata and Atlantic and in Mucugê-BA evaluating cultivar Ágata. The experimental design used was randomized blocks. We studied the rates of 0; 70; 110; 220, and 450 kg ha^-1 K₂O. The increase in K rate reduced the levels of S, Ca, Mg and B in Atlantic-Unaí, Ca, Mg, Zn and B in Ágata-Unaí and S, Fe and B in Ágata-Mucugê. The cultivar Atlantic-Unaí did not respond to the increase of potassium fertilizer dose, with a total of 32.3 to 37 t ha^-1. Cultivars Ágata-Unaí and Ágata-Mucugê responded to rates estimated at 225 and 166 kg ha^-1 K₂O with the highest productivities of 53.9 and 56.2 t ha^-1, respectively.

Keywords:
Solanum tuberosum; mineral fertilization; plant nutrition