A study of the effects of Nitrogen , phosphorus and potassium fertilizers on the dry matter yield and chemical composition of amaranthus hybridus sub-species hybridus (green head)

Plots of amaranthus hybridus sub-species hybridus (green head) were treated with N, P, and K fertilizers and sampled at a six day interval from day 42 to day 60 after sowing to determine the effect on DM yield and the resultant chemical composition. Treatments N1P0K0, N1P1K0 and N0P1K1 significantly out-yielded most of the other treatments, recording on the average on day 60, over7500kg DM/ha. Very high levels of % CP, %ash, %Ca, %P, %Ether Extract and %total oxalic acid was recorded and all these parameters decreased with the stage of plant growth, but there was no significant difference between the fertilizer treatments whereas significant difference between harvest dates was recorded. % DM, % OM, % CF and % NFE all increased with the stage of plant growth and significant difference between harvest days was recorded but no significant difference was shown between the various fertilizer treatments. Treatments N1P0K0 and N1P1K0 appeared best but since no significant differences was found between the two treatments, it is concluded that N1P0K0 treatment is desirable and economic. Harvesting on around 48 days post planting is also suggested.