| dc.description.abstract | Utilization of anorganic fertilizer on intensive crop cultivation for a long time causes a decrease in soil fertility, physical properties, and microbe activities, which results in decrease of land productivity. To improve this kind of soil, it is important to take a systematic action to increase soil organic material (SOM). SOM is very important material to improve soil structure as well as to increase the supply of mineral nutritiqn required for plant growth and production. Organic matter is also important for microbes activity within the soil, so that it can enhance soil fertility and productivity. In addition, soil microbes are important to help the processes of organic mineralization in the soil component which is required for plant to take up mineral nutrition. Indonesia has a very reach resources of biodiversity including many potential microbes called plant growth promoting rhyzobacteria (PGPR). Kinds of bacteria such as Azospirillum and Azotobacter has been known have a role in N2 fixation in tha nature, while another bacteria such as Bacillus and Pseudomonas have been known to be able to help the plant to absorb phosphorus and potaSSium. Utilization of organic matter and application of biofertilizer is a potential technology that is important to be developed to improve sustainable and renuable agriculture. | en |
