Department of Biology and Biotechnology, al-Farabi Kazakh National University, Almaty, 050038, Kazakhstan.
Laboratory of Rhizosphere Microflora, All-Russia Research Institute for Agricultural Microbiology. Sh, Podbelskogo 3, Pushkin, 196608, Saint-Petersburg, Russian Federation.
Curr Microbiol. 2022 Jul 6;79(8):240. doi: 10.1007/s00284-022-02926-1.
Large-scale screening of 848 culturable soil and endophytic filamentous fungi and yeasts for the ability to mobilize inorganic and organic P compounds was performed. Five strains of filamentous fungi having the highest level of phosphate-mobilizing ability were selected: Penicillium bilaiae Pb14, P. bilaiae C11, P. rubens EF5, Talaromyces pinophilus T14, and Aspergillus sp. D1. These strains in vitro actively solubilized Ca, Al, and Fe phosphates and Ca phytate. The amount of mobilized P negatively correlated with pH of the medium and positively correlated with fungal biomass. The proposed mechanisms for P mobilization were acidification of the medium, organic acid release, and phosphatase activity. The fungi decreased pH of the medium from 7.0 to 2.3-5.0. Ten different organic acids were produced by fungi with pyruvic acid being a major component. Acid phosphatase activity varied from 0.12 EU to 0.84 EU, and alkaline phosphatase activity varied from 0.08 EU to 0.61 EU depending on the strain. Available P concentration in soil was increased by 13-28% after introduction of the fungi. The fungi also produced phytohormones auxins, salicylic acid, and abscisic acid. All the strains, except Aspergillus sp. D1, promoted elongation and increased biomass of barley seedlings grown in soil. Shoot P concentration increased by 17-26% after inoculation with P. bilaiae Pb14, T. pinophilus T14, and Aspergillus sp. D1. It was concluded that the selected fungal strains promoted plant growth due to P mobilization and phytohormone production.
进行了大规模筛选 848 株可培养土壤和内生丝状真菌和酵母，以评估它们动员无机和有机磷化合物的能力。选择了 5 株具有最高磷酸盐动员能力的丝状真菌：双孢拟青霉 Pb14、双孢拟青霉 C11、红曲霉 EF5、松口蘑 T14 和曲霉 D1。这些菌株在体外能积极溶解 Ca、Al 和 Fe 磷酸盐和 Ca 植酸盐。动员的 P 量与培养基的 pH 值呈负相关，与真菌生物量呈正相关。提出的 P 动员机制是培养基酸化、有机酸释放和磷酸酶活性。真菌将培养基的 pH 值从 7.0 降低到 2.3-5.0。十种不同的有机酸由真菌产生，其中丙酮酸是主要成分。酸性磷酸酶活性在 0.12 EU 到 0.84 EU 之间变化，碱性磷酸酶活性在 0.08 EU 到 0.61 EU 之间变化，具体取决于菌株。引入真菌后，土壤中的有效磷浓度增加了 13-28%。真菌还产生植物激素生长素、水杨酸和脱落酸。除了曲霉 D1 之外，所有菌株都促进了在土壤中生长的大麦幼苗的伸长和生物量增加。接种双孢拟青霉 Pb14、松口蘑 T14 和曲霉 D1 后，植株的 P 浓度增加了 17-26%。结论是，所选真菌菌株通过动员 P 和产生植物激素来促进植物生长。
