Growth, yield and root-shoot assimilate distribution in Amaranthus cruentus L. As influenced by different urine-water dilutions

Abstract

The agronomic performance of Amaranthus cruentus L. improves with the application of fertilizers. Wastes, including human urine, which often contribute to environmental pollution, can be recycled into cost-effective fertilizers for amaranth cultivation. Therefore, this study evaluated the response of A. cruentus to NPK (15:15:15), urine-water dilutions (UWD) at ratios of 1:2, 1:4 and 1:6 and a control with no nutrient additive. The treatments except control were applied at 100 kg N ha⁻¹; and all were laid using randomized complete block design with four replicates. Data on plant height, stem girth and number of leaves were collected at 3 and 4 weeks after sowing (WAS); and yield components at 4 WAS. Amaranth in NPK-treated soil had highest plant height (62.66 cm) and stem girth (2.71 cm) at 4 WAS, and compared statistically with 1:2 UWD treatment. The maximum number of leaves at 4 WAS (16.63) was obtained from 1:6 UWD treatment, differing significantly from other treatments except NPK and 1:4 UWD. Meanwhile, 1:4 UWD gave the highest dry weight of edible part (0.70 g plant⁻¹), though statistically at par with 1:2 and 1:6 UWDs. Notably, the highest percentage of root in whole plant (13.14%) was recorded from control followed by NPK fertilizer (7.76%). The urine water dilutions influenced growth of A. cruentus positively and resulted into more assimilate partitioning to the edible parts. However, 1:4 UWD is recommended for its highest edible part and could be adopted as fertilizer for A. cruentus cultivation.