A Study on the Effect of Potassium on Growth
and Salt Tolerance of Watermelon Cultivars

Peiman Jafari & Hamid Molahoseini

Isfahan Agricultural Research Center, Isfahan, Iran
e-mail: peimanjafari@yahoo.com


Abstract

This study carried out to evaluate the effect of potassium(K2O)  on salt tolerance of watermelon cultivars in Eshragh Industrial and Farming Company  that situated at the south west of Varamin. The experiment design was split plot as follow: Main factor  wasWatermelon cultivars  including Sugar baby (Su), Charleston Grey (Ch) and Crimson Sweet (Cr). Sub factor was different rates of Potassium (K2O) as potassium sulfate (K2SO4) including: Control (K0), use of Potassium (K2O) base on  soil test (K25), use of Potassium (K2O) base on  two and three times more than soil test results (K50, K75). The other necessary nutrition applied according to the soil test results. The result of combined analysis variance showed that there was  highly significant difference (P≤%1) in weight of total fruit, weight of one fruit and fruit number per plant in all treatments . Fruit skin thickness  and weight of 1000 seed  were highly significant difference (P≤%1) in cultivar treatments and Total Soluble Solids was highly significant difference (P≤%1) in potassium (K2O) treatments. The mean comparisons of results according to Duncan`s multiple range test showed that the highest weight of total fruit and weight  of one fruit were 39.1 Ton.ha-1 and 3.1 kg in ChK75  treatment respectively and  the highest fruit number per plant was 1.5 in SuK75 treatment, which all were located in A class. On the whole ,base on  results of this experiment, extra use of K2O in the saline soils under watermelon cultivation, prevention of  yield decrease due to salinity.

 Keywords: Watermelon, Salt Tolerance, Potassium