Ice Nucleation Active bacteria in Mount Lawu forest, Indonesia: 3. Isolation and estimation of bacterial populations on bryophyte

Abstract. Latifah NH, Susilowati A, Suratman. 2018. Ice Nucleation Active bacteria in Mount Lawu forest, Indonesia: 3. Isolation and estimation of bacterial populations on bryophyte. Asian J For 2: 67-75. This study aimed to isolate and estimate the Ice Nucleation Active (INA) bacteria population on bryophyte from the trekking route of Cemoro Sewu, Mount Lawu, Indonesia. Bryophyte samples were taken at three different altitudes, i.e., 2,000, 2,300, and 2,500 m above sea level (asl). Isolation of INA bacteria was carried out by the method of spread plate on King's B and nutrient agar plus 2.5% glycerol (NAG) medium. Bryophyte was identified by referring to the literature of Sutama (1995), Hasan and Ariyanti (2004), Ignatova and Samkova (2006), and Damayanti (2006). Ice nucleation activity was determined by the multiple-tube test method. The bacterial suspension tube was put into the circulating alcohol bath at a temperature of -10°C for 5 minutes. The number of INA bacteria on the bryophyte was estimated with the nucleation multiple tube method. The number (cell/g) of INA bacteria from the fresh weight of bryophyte was estimated based on the Most Probable Number (MPN) tables according to the formula of Thomas's 333 series. INA bacteria were identified through morphological and biochemical characters. Independent Sample T-Test analyzed the population of INA bacteria on terrestrial and epiphytes bryophytes with a significance of 5%. The results showed that 7 INA bacteria were isolated from the bryophyte Campylopus umbellatus (Arn.) Paris (Leucobryaceae, Musci). The population of INA bacteria in terrestrial bryophytes at each altitude were greater with 346 cell/g, 86 cell/g, and 396 cell/g, respectively, than that in epiphytes bryophyte with 50 cell/g, 50 cell/g, 176 cell/g, respectively.