Development of Passiflora cincinnata Mast. submitted to different levels of nitrogen and potassium

Resumen

The present study aimed to evaluate the morphological characteristics of passion fruit (Passiflora cincinnata Mast.) under different levels of nitrogen and potassium, and interactions between these nutrients. The experimental design was randomized blocks, with a 4 x 4 factorial arrangement of treatments, three replications per treatment and 48 experimental plots and the experimental unit was composed of one plant. Factors were four doses of N (0, 75, 150 and 300 mg of N dm^-3 of soil, applied as urea, 45 % N), and four doses of K (0, 150, 300 and 600 mg of K dm^-3 of soil, applied as potassium chloride, 60 % K₂O). After 60 days of transplanting the seedlings to pots, stem diameter, leaf number, SPAD (Soil Plant Analysis Development) index, leaf area, dry weight of shoot and root were evaluated. The interaction effect between levels of N and K was observed when the dry weight of shoot, stem diameter and SPAD index was assessed. The greatest growth rate of Passiflora cincinnata Mast. was obtained at doses of 180 to 300 mg of N dm^-3 of soil. Potassium rates used in this study reduced the potential for accumulation of dry mass of the shoots.