Potensi Khamir Endofit Buah Markisa (Passiflora Edulis) Penghasil Asam Indol Asetat Dan Pelarut Fosfat

Abstract

Endophytic yeast is a unicellular fungus whose their life cycle in tissues such as intercellular spaces of plants and does not cause damage to its host. Their ability in secreting of phytohormone and dissolving of phospates can be used as nutrients. This study aims to determine the population of endohpytic yeasts on passion fruit (Passiflora edulis) and their ability to produce indole acetic acid (IAA) and to dissolve phosphate. The endophytic yeast was isolated from seed membrane of passion fruit. As much as 25 ml of the fruit juice was put on sterile erlenmeyer (500 ml size) and 250 ml sterile aquadest was added. The suspension was homogenized and serial dilutions was carried out by aliquote 1 ml of dilutions and placed into a petri dish containing malt extract agar (MEA). All plates were incubated at 29°C for 7 days and each treatment was repeated 3 times. Yeast colonies were enumerated, isolated and a single colony was subcultured on potato dextrose agar (PDA) medium. Identification of isolates were determinated and morphological characteristic was observed directly on the MEA medium, yeast identification was continued by chemically test using VITEK 2 Compact method. IAA determination was carried out by culturing each yeast isolate on yeast malt broth (YMB) medium containing 0.1% L-tryptophan and all cultures were incubated for 5 days in the dark at 29°C. The ability of the yeast to dissolve phosphate was determined using the Pikovskaya medium. There are two species of endophytic yeast, were found namely Meyerozyma guilliermondii and Debaryomyces hansenii with populations of 3x106 and 8x106 cfu/ml. Both of the yeasts, M. guilliermondii and D. hansenii were able to produce IAA of 58.47 and 79.98 ppm respectively. Debaryomyces hansenii has higher phosphate solubilization (16.1 mm) than Meyerozyma guilliermondii (15.3 mm).