2. Materials and methods
In this study, three experiments were conducted in the
Xiengngeun district, Luang Prabang province in northern Laos.
Experiment 1 (Exp. 1), conducted at the Houay-Khot (HK1) and
Long-Or (LO1), consisted of two fertilizer treatments (main-plot),
four application levels of biochar (sub-plot) and two rice cultivars