Bacterial Diversity on the Application of Methanotrophic Bacteria in Rainfed Rice of Kupang Regency, East Nusa Tenggara, Indonesia

Paddy fields are the main anthropogenic source of methane emissions as a greenhouse gas that causes global warming. In this research, methanotrophic bacteria as biological fertilizers are used to reduce methane gas in rainfed rice fields and study the diversity of bacteria based on the application of these fertilizers. This research began with the cultured of the bacterial cultures of Methylocystis rosea BGM 1, Methylocystis palvus BGM 3, M. capsulatus BGM 9 and Methylobacter sp. SKM 14. Furthermore, culture production and application are carried out in rainfed rice fields. The treatments consisted of: (1) NPK 100% (P1), (2) NPK 50% (P2), (3) without fertilizer application (P3), (4) NPK 100% + Metanotrophs (P4), (5) NPK 50% + Metanotrophs (P5), and (6) Metanotrophs (P6). Analysis of the diversity of bekteri using the Deanaturing Gradient Gel Eltrophoresis (DGGE) technique. The study of bacterial diversity based on the 16S rRNA gene showed that the proteobacteria genus dominated the habitat consisting of the gammaproteobacteria, alfaproteobacteria and deltaproteobacteria classes.