German Institute for Agriculture in the Tropics and Subtropics (DITSL GmbH)
Doi
Abstract
Biochar application to soils increases biomass and crop yields, especially with rates higher than 100 t ha−1. Yet, there is limited knowledge on the combined effect of biochar and chemical fertiliser under different tillage systems. The objective of this study is to investigate the effect of maize-cob biochar (BC) (rates of 5 and 10 t ha−1) combined with chemical fertiliser micro-dosing (MD) at a rate of 25% of the recommended quantity on total shoot dry matter (DM) and plant height of maize cultivated under flat (F) and tied-ridge (R) practices during a humid season in Tanzania. The results indicate that combining 5 t ha−1 BC with 25% MD increases DM at harvest by 83% (4.16 t ha−1) compared to the control (2.27 t ha−1) and was in the same range as the DM obtained from the treatment with the recommended fertiliser rate (100% FD). The treatments with single applications of 25% MD, 5 t ha−1 BC, and 10 t ha−1 BC only tended to exceed the control of DM yield. Therefore, we recommend that small-scale farmers aiming at DM for livestock or grain yield with limited access to chemical fertilisers to combine biochar with 25% MD, rather than applying biochar or low chemical fertiliser rates alone