|| 要旨トップ | 目次 |||日本生態学会第66回全国大会 (2019年3月、神戸) 講演要旨
一般講演（口頭発表） D01-06 （Oral presentation）
Nitrogen is an essential element for plant development and metabolism. It can be synthesized as nitrogenous substances that plants needed, such as amino acids, nucleic acids. However, the nitrogen sources that plants can use directly are nitrate and ammonium, which came from chemical-fertilizer or produced by microorganisms. However, too much chemical-fertilizer cause nitrate accumulation in the soil and crops. Here we collected the wild cherry tomato to isolate the yeasts from its rhizosphere. Totally 41 yeasts were isolated from its rhizosphere, and they were evaluated for their nitrogen fixation, ammonia production and plant-growth-promoting ability. Here we reported that 14 yeasts show nitrogen fixaion ability on nitrogen-free plate and all can produce ammonia (from 0.31 to 1.95 µmol/ml) and indole-3-acetic acid (from 25.08 to 364.07 μM) when tryptophan as the precursor. In addition, 12 strains of these candidates are able to produce siderophore, five strains are with calcium phosphate and two with zinc oxide solubilizing ability, and 6 strains are with chitinase activity. These selected yeasts will be further inoculated with Arabidopsis thaliana to evaluate their ability to promote plant growth. The results highlight the potential use of yeasts as plant bio-fertilizers under controlled and field conditions.