Li Siyu, Han Ruiming, Zhang Huanshi, Song Yongchun, Zhao Fugeng, Qin Pei
Halophyte Research Lab, Nanjing University, Nanjing 210008, China.
Qu Jiang Experimental Middle School, Quzhou 324022, China.
Microorganisms. 2020 Nov 26;8(12):1868. doi: 10.3390/microorganisms8121868.
A newly isolated phosphate-solubilizing fungus from the topsoil of habitats in Yancheng coastal salt marsh was cultivated. Scanning electron microscopy observation revealed that the sporangia are nearly spherical, peach-shaped, and the spores formed on the top of sporangia. The spores are ellipsoidal with raised white nubbins on the surface. Based on a polyphasic study and the genetic distance analysis referring to the sequence analysis of ITS (ITS1 + 5.8S + ITS2) and 28S rDNA (D1/D2 domains) genes, the novel species belongs to the genus and is named as . The optimum growth temperature and salinity of the new species were 28 °C and 1.15% NaCl, respectively. A study of its phosphate-solubilizing ability revealed that the fungus had an obvious decomposition effect on lecithin, Ca(PO), and AlPO, respectively. The pH of the fermented liquid progressively decreased from 6.85 to 2.27 after 7 days of incubation, indicating that the low molecular weight organic acids excreted into the culture liquor were oxalic, succinic, and malic acids and a trace amount of citric acid. Among these, oxalic acid was the major organic acid, and its amount reached 652.5 mg/L. These results indicated that the main mechanism underlying the dissolved phosphorus was related to the secretion of large amounts of organic acids.
对从盐城沿海盐沼生境表土中新分离出的一株解磷真菌进行了培养。扫描电子显微镜观察显示，孢子囊近球形、桃形，孢子在孢子囊顶部形成。孢子呈椭圆形，表面有凸起的白色瘤状物。基于多相研究以及参考ITS（ITS1 + 5.8S + ITS2）和28S rDNA（D1/D2结构域）基因序列分析的遗传距离分析，该新物种属于 属，并被命名为 。该新物种的最适生长温度和盐度分别为28℃和1.15% NaCl。对其解磷能力的研究表明，该真菌分别对卵磷脂、Ca(PO)和AlPO有明显的分解作用。培养7天后，发酵液的pH从6.85逐渐降至2.27，表明分泌到培养液中的低分子量有机酸为草酸、琥珀酸、苹果酸和微量柠檬酸。其中，草酸是主要有机酸，其含量达到652.5 mg/L。这些结果表明，溶解磷的主要机制与大量有机酸的分泌有关。
