Potassium uptake efficiency of two pear cultivars and leaf concentration at deficiency symptoms appears

Two pear cultivars (Meski Ahrech and Alexandrine) grown in pot culture under normal daylight conditions in a greenhouse were submitted to potassium deficiency treatments. The potassium-free treatment decreased leaf K concentration, relative water content, SPAD, and gas exchange comparatively to the control. "Alexandrine" appeared more sensitive to potassium deficiency due to the main decrease in stomatal conductance (gs), photosynthesis (A) and transpiration (E) compared to "Meski Ahrech" that reduced only carbon assimilation (A). After 42 days of treatments, leaf K concentration in "Alexandrine" was 0.75% DM compared to 1.15% DM in "Meski Ahrech", which appeared to be more efficient in potassium uptake.