Nutritional contents in Myrciaria dubia plants in function of in Potassium doses applied through fertigation

The objective in this study was to determine the nutrient contents in Myrciaria dubia plants in function of five K2O doses (0, 40, 80, 120 and 160 kg ha-1) applied through fertigation. Leaf dry matter (LDM), total dry matter (TDM), and leaf nutrient contents were evaluated. The LDM and TDM were higher in plants subjected to the dose of 160 kg ha-1 of K2O, with 52.44 g and 302.69 g, respectively. Leaf N and K contents were 22.15 and 9.48 g kg-1 in response to 160 kg ha-1 of K2O. The mean P, Ca and S contents were 1.6, 17.89 and 1.61 g kg-1, respectively, and the content of Mg2 + decreased from 5.62 to 2.74 g kg-1 at the dose of 0 and 160 kg ha-1 of K2O, respectively. The B, Mn and Fe contents decreased from 136.5 to 100.0, 346.24 to 248, and from 142.06 to 97.35 mg kg-1 at the dose of 0 and 160 kg ha-1 of K2O, respectively. The mean Cu and Zn contents were 3.81 and 40,54 mg kg-1, respectively, at the K2O doses. The nutrient content determined in the leaves of M. dubia were adequate for the development of the species in the first year of cultivation, presenting the following decreasing order: N> Ca> K> Mg> P = S> Mn> B> Fe > Zn> Cu.