Yield response of green amaranth to the residual fertilizers previously applied to carrot genotypes (Daucus carota L.) in Nsukka, Southeast Nigeria

Abstract

The study was carried out at the Teaching and Research Farm of University of Nigeria, Nsukka to determine the residual effects of previously applied fertilizers to three genotypes of carrot on the performance of the succeeding crop, green amaranth. The treatments were 0 t/ha (control), 20 t/ha poultry manure (PM), 20 t/ha pig manure (PiM), 10 t/ha PM + 200 kg/ha NPK 15:15:15 and 10 t/ha PiM + 200 kg/ha NPK 15:15:15 previously applied to three genotypes of carrot, Safety Touchon France genotype plot 1 (P1), Carotte Touchon AM genotype plot 2 (P2) and Carotte Touchon ETS genotype plot 3 (P3). The experiment was laid out as split-plot in Randomized Complete Block Design with four replications. The plants transplanted to P1 had the highest nonsignificant mean values of 38.1g, 101.2, 26.5g per plot for foliage (leaves, stalks, and stems) weight, number of leaves and fresh leaf weight respectively while P3 produced the least nonsignificant yield values. Amaranth plants grown in P2 best expressed whole plant biomass, number of harvested plants and survival rate. The residual fertilizers significantly (p ≥ 0.05) influenced whole plant biomass, foliage weight, and number of leaves of green Amaranth. The interaction of Carotte Touchon AM genotype plot and 10t/ha PM + 200kg/ha NPK 15: 15:15 gave the highest values 8.0, 92.2g, 131.8, 37.7g and 66.7 % for all parameters measured except in foliage weight. The study showed that previously applied fertilizers sustained crop establishment and yield of green amaranth.