Phosphorus Rate for Vegetables Grown in the Ultisols, Nanggung, Bogor, Indonesia

Abstract

Amaranth (Amaranthus sp.), kangkung (Ipomoea aquatica L.), eggplant (Solanum melongena L), chili (Capsicum annuum L.), tomato (Lycopersicon esculentum Mill), green bean (Phaseolus vulgaris L.), and yard -long bean (Vigna unguiculata L.) were grown on Ultisols soil of Nanggung with low pH (5.2), low organic C (1.70%), very low total N (0.21%), low K content (0.33 mellOO g), but high soil P20 S concentration (10.8 ppm) to optimize P rate application. Treatments were Prate: 0,45, 90, 135 and 180 kg P205/ha or equal to 0, 125, 250, 375 and 500 kg SP36 (36% P20s)/ha. Treatments were arranged in Randomized Completely Block design with three replications. In the level of soil P concentration of 10.8 ppm (Bray-I) of Ultisols, application of P fertilizer up 180 kg P205/ha linearly increased plant height of kangkung, eggplant, chili, tomato, yard-long bean and green bean and linearly increased yield of amaranth, kangkung, eggplant, chili, tomato and green bean. To achieve optimum P fertilizer rate, the range of P rate application needs to be increased.