EFFECT OF POTASSIUM FERTILIZER AND SALT STRESS ON GROWTH AND YIELD OF ONION (ALLIUM CEPA L.) CULTIVATED IN GYPSIFEROUS SOIL

A field experiment was conducted in gypsiferous soil in Salah Al-Din governorate according to Randomized Complete Block Design (RCBD) with three replicates, to study the effect of potassium fertilizer and salinity of irrigation water on growth, yield of onion and the amount of potassium residue in the soil after harvest. Potassium levels (0, 80 and 160) kg ha(-1) were used from the source K2SO4 and the quality of irrigation water with EC levels (0.58, 2.02 and 3.38) dsm(-1). The results showed that potassium fertilizer led to a significant increase in the growth and yield indicators studied and that there is a response in the gypsiferous soil added potassium. The salinity of the irrigation water used led to a significant increase in ready potassium (dissolved and exchanged) after harvest.