Effect of Method, Levels and Time of Potassium Fertigation on Available potassium during the Growing Season of Tomato(Lycopersicon esculentum Mill)

Abstract

A field experiment was conducted during the growing season of 2013-2014 oftomato grown under plastic house the study effect of Potassium Fertigation on available K insoil. Potassium (K2SO4)as source of potassium was added at rates of 0,100,200,300,400 and500 kg ha-¹ at four methods(conventional method, 50% to soil +50% fertigation, equal dosesmethod divided at seven dosed and fertigated to plant with (12) days intervals and accordingto plant growth stage. Soil sample (0-30 cm) were collected at five stage of plant growth(50% flowering ,50% fruitage ,50% maturity ,full maturity and at end of season). availableK was determined. Result showed that applied K as fertigation according to plant growthstage or 50% to soil +50% fertigation resulted in highest available K in soil compared withother application. Result also that K concentration in soil increased with increasing K rate.Highest K concentration in soil (317.63gm kg-¹soil)found at growth 50% fruitage at rate of500kg K ha.