Isolasi dan karakterisasi bakteri tanah sawah di desa sukawali dan desa belimbing, kabupaten tangerang

Abstrak Penggunaan pupuk kimia secara berlebih dapat menyebabkan kerusakan tanah dan menyebabkan ekosistem yang ada didalamnya terganggu. Plant growth-promoting rhizobacteria (PGPR) adalah bakteri yang hidup di daerah rizosfer tanaman yang dapat berperan sebagai biofertilizer, biostimulan dan bioprotektan. Penelitian ini bertujuan untuk memperoleh dan mengetahui karakteristik bakteri tanah yang berasal dari dua area persawahan, lokasi pertama di Desa Sukawali (TGR 1) dan lokasi kedua di Desa Belimbing (TGR 2), Kabupaten Tangerang. Penelitian dilakukan dengan mengambil sampel tanah, kemudian sampel dikultur dalam media agar nutrien dengan pengenceran bertingkat. Total bakteri dihitung dan isolat yang diperoleh diuji kemampuan dan karakternya dalam menambat nitrogen (BPN), melarutkan fosfat (BPF), menghasilkan indole acetic acid (IAA), menghasilkan Hidrogen Cyanide (HCN), aktivitas katalase, jenis Gram dan karakter motilitas. Total bakteri yang dapat tumbuh dari kedua lokasi sebanyak 2,4x106 CFU/g dan 1,8x106 CFU/g. Kedua lokasi diperoleh total 45 isolat dengan seluruhnya positif BPN, 42 isolat positif BPF, 24 isolat menghasilkan IAA, 27 isolat menghasilkan HCN, 43 isolat katalase positif, 39 isolat Gram positif, 6 isolat Gram negatif, serta 41 isolat motil. Berdasarkan uji yang dilakukan, terdapat 16 isolat yang berpotensi sebagai pupuk hayati. Abstract Excessive use of chemical fertilizer may cause soil damage and disturb the ecosystem. Plant growth-promoting rhizobacteria (PGPR) is a consortium bacteria that live in plant rhizosphere which acts as biofertilizer, biostimulant, and bioprotectant. The objective of this research is to isolate and investigate the characteristics of soil bacteria originating from two rice fields in Sukawali Village (TGR 1) and Belimbing Village (TGR 2), Tangerang Regency. The research was conducted by collecting soil samples and then culturing the bacteria onto nutrient agar medium with serial dilution. The total bacteria were calculated and the isolates obtained were examined for their ability and characteristics on nitrogen-fixation, phosphate solubilization, IAA production, HCN production, catalase activity, Gram assay, and motility. The total plate count from both TGR 1 and TGR 2 were 2.4x106 CFU/g and 1.8x106 CFU/g, respectively. From these locations 45 isolates obtained were positive nitrogen-fixer, 42 isolates were phosphate solubilizer, 24 isolates were IAA producer, 27 isolates were HCN producer, 43 isolates were catalase positive, 39 isolates were Gram-positive, 6 isolates were Gram-negative, and 41 isolates were motile. On the whole results, it was concluded that there were 16 isolates that could potential as biofertilizer.