Mitigating drought stress in Coffea arabica L. seedlings through soil stabilization with corncob derived biochar

While various studies have attempted to investigate the efficacy of biochars in enhancing plant seedlings, research on the application of biochar specifically for Coffea arabica L. seedlings in drought conditions remains restricted. To reveal the mitigation of biochar in the Coffee. seedlings under drought stress, the impacts of different biochar doses on soil physicochemical, biological, and hydrological parameters, as well as the growth of Coffee seedlings were evaluated. To mimic the effect of drought stress, utilizing three different levels of water holding capacity (20 %, 40 %, and 60 % of WHC) was performed with three different corncob biochar application rates of 1 %, 2.5 %, and 5 % w/w of soil. The results revealed that corncob biochar application increased pH, cation exchange capacity and organic matter. While soil microbial respiration, microbial biomass carbon, and dissolved organic carbon had increased in application biochar 1 and 5 % under both drought and no drought conditions. Corncob biochar at 1 % application rate enhanced the growth and chlorophyll content under drought condition significantly ( p < 0.05). However, no statistically significant differences were observed between biochar application and water holding capacity on membrane damage and total soluble sugar content under drought conditions. The relative water and proline content had increased in biochar application at 1 %. Based on these findings, the application of biochar into coffee seedling production systems may help mitigate the adverse effects of water scarcity while promoting long-term soil health and agricultural resilience, particularly in tropical and subtropical highland regions where climate change-induced drought events are becoming more frequent. • Biochar increase soil microbial respiration, microbial biomass carbon, and dissolved organic carbon under drought condition. • Higher application rates (2.5 % and 5 %) led to a decrease in available phosphorus and lower coffee seedling growth. • 1 % biochar enhanced the chlorophyll content, relative water content, and proline accumulation under drought stress.