Growth, biomass productivity, nitrogen uptake and use efficiency of selected enset clones in southern Ethiopia

Enset ( Ensete ventricosum ) is a staple food crop for over 20 million people in southern Ethiopia. As climate change intensifies, its importance for food security increases, and its cultivation is also expanding into new territories such as the warmer and drier lowlands. This study evaluated the responses of two enset clones (Ganticho and Nifo) to six different integrated soil fertility management (ISFM) alternatives on establishment, vegetative growth, biomass production, nitrogen uptake, nitrogen use efficiency (NUE), biomass partitioning, and soil chemical properties. A factorial experiment was conducted using a randomized complete block design with three replications. The ISFM treatments comprised: control, 100% recommended inorganic nitrogen (N), 100% recommended vermicompost (VC), 75% VC + 25% N, 50% VC + 50% N, and 25% VC + 75% N. Enset establishment traits were not significantly affected by clone, ISFM, or their interaction, although treatments with vermicompost improved plant survival. In contrast, vegetative growth, biomass yield, nitrogen uptake, and NUE were significantly influenced by both clone and ISFM. Ganticho produced greater biomass and corm development than Nifo, indicating the clone’s better adaptation and productivity under lowland conditions. Significant Clone × ISFM interactions were observed for stem, corm, root, and total dry matter, demonstrating genotype-specific responses to nutrient management. Ganticho allocated more biomass to corm development, whereas Nifo invested relatively more in root growth, reflecting contrasting resource-use strategies. Clone × ISFM interactions also significantly affected NUE components, confirming differences in nutrient utilization between clones. In addition, ISFM treatments improved soil organic carbon, total nitrogen, available phosphorus, pH, and cation exchange capacity. These findings demonstrate that enset productivity in lowland environments is strongly influenced by genotype × nutrient management interactions, highlighting the importance of integrating vermicompost-based fertilization with suitable clone selection to enhance biomass production, nitrogen use efficiency, and sustainable soil fertility.