Modificarea relaţiei source-sink la cartof (Solanum tuberosum L.) prin fertilizare cu clorură şi sulfat de potasiu

Abstract

In a pot experiment, the effect of 1% K2SO4 foliar fertilization combined with KCl soil fertilization on the source - sink relationships of Solanum tuberosum L. plants cv. Desireé was evaluated and compared to K2SO4 fertilization. The foliar application of K2SO4 at KCl variants did not increase the shoot dry weights but significantly increased the chlorophyll concentration in the leaves, thus increasing the plants’ photosynthesis. The foliar application of K2SO4 at KCl variants increased the tuber yield. Notably, this increase was due to increase of the tuber number whereas the starch concentration, however, remained constant. The source - sink relationship was modified by a sink extension; the foliar application of K2SO4 accelerated the tuber development. The concentration of all cations analyzed was found within normal ranges in all variants included in this study. Plants fertilized with KCl did not present visible symptoms of leaf chlorosis or necrosis, except for a slight yellowing at a concentration of 21 g Cl-/g DW.