Effect of Poultry Manure on Growth, Nutrients Composition and Heavy Metal Content of Amaranthus caudatus L.

The aim of this study was to evaluate the effect of poultry manure on the growth of Amaranthus caudatus with a view to establishing the optimum poultry manure treatment for its growth. The study was carried out between the months of February and May 2020, in a portion beside the botanical garden in the University of Benin, consisted of three (03) treatments namely PM1 (10%), PM2 (20 %), and PM3 (30 %) with poultry manure and control (PM0) in a randomized complete block design (RCBD) and replicated three times. Data for growth parameters (height, number of leaves, leaf area, and number of branches) were collected from 1 to 6 weeks after transplanting (WAT). At 6 WAT, PM1 recorded the highest values for growth. At that time, PM1, PM2 and PM3 recorded leaf area values of 111.66±24.11 cm2, 74.33±3.17 cm2, 64.66±22.34 cm2
, respectively compared to the control with 5.33±0.33 cm2. PM1 showed enhancing effect on proximate composition of ash, lipid, crude protein, crude fibre and dry matter compared to control. Carbohydrate and moisture content were higher in PM0. A. caudatus grown in 10 % poultry manure treatment (PM1) elicited high levels of Ca, Mg, K, Na, P, Zn and Fe. Total lead in A. caudatus plants derived from PM1 was higher than PM0. The results of this study shows that PM1 elicited higher yield in A. caudatus when compared with other treatments and is therefore recommended for growing the plant.