Correlation Study of Soil-P Test for Vegetables Grown in the Ultisols at Nanggung, Bogor, Indonesia

Abstract

Phosphorus (P) correlation experiment has been done in Ultisols in Nanggung District, Bogor, Indonesia from 2006-2007 to find the best P extraction method suitable for vegetables i.e. amaranth (Amaranthus sp.), kangkung (Ipomoea aquatica L.), eggplant (Solanum melongena LJ, chili (Capsicum annuum L.), tomato (Lycopersicon esculentum Mill), green bean (Pahaseolus vulgaris L.) and yard-long bean (Vigna unguiculata L.). Treatments were Prate: 0, 45, 90, 135 and 180 kg/ha P20 S equal to 0, 125, 250, 375 and 500 kg/ha SP36 (36% P20 S). Treatments were arranged in Randomized Complete Block design with three replications. Soil samples were taken from every plot and analyzed with five extraction methods (25% HCl, Morgan Vanema, Bray-I, Mehlich and Olsen). Soil analysis results were correlated with the relative yield of each vegetable. The best soil extraction method is that which showed highest correlation with vegetable relative yield. Olsen method showed highest correlation with amaranth, chili and tomato relative yield; 25% HCL with yard-long bean and eggplant; and Morgan Vanema kangkung relative yield and Bray-l for green bean