Improvement of soil quality using bokashi composting and NPK fertilizer to increase shallot yield on dry land

The use of NPK fertilizer and bokashi composting, which is a fermented organic matter combined with microbial stock, have been reported as potential agricultural practices to enhance the farming land and crop production. The aim of this research is to understand the type of bokashi fertilizer and the correct dosage of NPK inorganic fertilizer in improving entisol soil quality and shallot yield in the dry land. The research used the split-plot design, which was divided into two factors. The first factor of the main plot was the bokashi type consisting of two levels: 3 t ha -1 of bokashi compost of Gliricidia sp. tree leaves (B1); and bokashi cow manure 3 t ha -1 (B2). The second factor as the subplot was the NPK inorganic fertilizer dose which were consisted of four levels: without fertilizers (K0), NPK 100 kg ha -1 (K1), NPK 200 kg ha -1 (K2), and NPK 300 kg ha -1 (K3). By combination of these two factors 8 combined treatments with 3 replications totally 24 units were obtained. The result of the research showed that application of 3 t ha -1 bokashi cow manure (B2) coupled with NPK inorganic fertilizer at 200 kg ha -1 (K2) caused a decrease in evaporation of its land and soil temperature, while increase shallot bulb yield compared with other treatments. The analysis of soil and soil microbes showed an increase in soil fertility by elevated levels of C-organic from 0.66 % to 3.28 %, N-fixing bacteria from 27 x 10 5 CFU ml -1 to 47 x10 6 CFU ml -1 and phosphate solubilizing bacteria from 20 x10 3 CFU ml -1 to 90 x10 3 CFU ml -1