Liquid bio-slurry enhances the productivity of N-fertilized maize under field conditions in Ethiopia

Zekarias Yohannes; Tarekegn Yoseph; Alemayehu Kiflu; Tewodros Ayalew; Ashenafi Haile

doi:10.52756/ijerr.2024.v43spl.002

Authors

Zekarias Yohannes Hawassa University College of Agriculture, P.O.Box 05, Hawassa, Ethiopia; Wolaita Sodo University, P.O. Box 138, Sodo, Ethiopia https://orcid.org/0009-0007-0380-1347
Tarekegn Yoseph Hawassa University College of Agriculture, P.O.Box 05, Hawassa, Ethiopia https://orcid.org/0000-0002-4629-4089
Alemayehu Kiflu Hawassa University College of Agriculture, P.O.Box 05, Hawassa, Ethiopia https://orcid.org/0000-0002-9227-3289
Tewodros Ayalew Hawassa University College of Agriculture, P.O.Box 05, Hawassa, Ethiopia https://orcid.org/0009-0003-2766-4114
Ashenafi Haile Hawassa University College of Agriculture, P.O.Box 05, Hawassa, Ethiopia https://orcid.org/0000-0003-3303-4031

DOI:

https://doi.org/10.52756/ijerr.2024.v43spl.002

Keywords:

Food security, grain yield, mineral fertilizer, productivity, soil amendment

Abstract

Enhancing maize production and productivity is critical for ensuring small-scale farmers' food security. Yet, declining soil fertility poses a substantial challenge to cereal production, including maize, in developing countries. Farmers are currently finding liquid bio-slurry to be a valuable organic amendment because it improves maize productivity and food security by altering the physicochemical properties of the soil. However, extensive research on liquid bio-slurry as an organic amendment in Ethiopia is still limited. Hence, a field experiment was conducted at two sites to identify the optimal combination of inorganic nitrogen (N) and liquid bio-slurry to improve maize productivity. The trial involved the application of two mineral N fertilizers and five different rates of liquid bio-slurry in a randomized complete block design with three replications. The results revealed that the main effects of mineral N and liquid bio-slurry were significant (p< 0.05) on most of the parameters examined. The interaction between mineral N x liquid bio-slurry had a significant (p< 0.05) effect on plant height, ear length, number of rows ear^-1, number of kernels ear^-1, above-ground dry biomass yield, hundred-grain weight, grain yield, and straw yield. The highest grain yield (8,220 kg ha^-1) was achieved by combining 46 kg N ha^-1 with 18 t liquid bio-slurry ha^-1. Therefore, 46 kg N ha^-1 with 18 t liquid bio-slurry ha^-1 is highly recommended for increasing maize yield in the study sites and other areas with similar agroecological zones.

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