Yang Tianyou, Li Linbo, Wang Baoshi, Tian Jing, Shi Fanghao, Zhang Shishuang, Wu Zhongqi
School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, China.
Sino-Danish Center, University of Chinese Academy of Sciences, Beijing, China.
Front Microbiol. 2022 Apr 25;13:793122. doi: 10.3389/fmicb.2022.793122. eCollection 2022.
The highly effective phosphate-solubilizing microorganisms are significant for making full use of the potential phosphorus resources in the soil and alleviating the shortage of phosphorus resources. In this study, a phosphate-solubilizing fungus was isolated from wheat and cotton rhizosphere soils in the lower reaches of the Yellow River in China and was identified as by morphological and ITS sequencing analysis. In order to obtain a fungus with more efficient phosphorus solubilization ability, we tested three positive mutant strains (P1, P2, and P3) and three negative mutant strains (N1, N2, and N3) through low-energy nitrogen ion implantation mutagenesis. Compared with the parental strain, the phosphate-solubilizing capacity of P1, P2, and P3 was enhanced by 56.88%, 42.26%, and 32.15%, respectively, and that of N1, N2, and N3 was weakened by 47.53%, 35.27%, and 30.86%, respectively. Compared with the parental strain, the total amount of organic acids secreted significantly increased in the three positive mutant strains and decreased in the negative mutant strains; the pH of culture medium was significantly lower in the positive mutant strains and higher in the negative mutant strains. The capacity of phosphate-solubilizing fungus to secrete organic acids and reduce the growth-medium pH was closely related to its phosphate-solubilizing ability. The changes in the amount of organic acids secreted by mutants can alter their acidification and phosphate-solubilizing capacity. In conclusion, this study offers a theoretical basis and strain materials for the exploration and application of phosphate-solubilizing fungi.
高效解磷微生物对于充分利用土壤中的潜在磷资源和缓解磷资源短缺具有重要意义。本研究从中国黄河下游地区的小麦和棉花根际土壤中分离出一株解磷真菌，并通过形态学和ITS测序分析将其鉴定为[具体菌种未给出]。为了获得具有更高解磷能力的真菌，我们通过低能氮离子注入诱变试验了三株正向突变菌株（P1、P2和P3）和三株负向突变菌株（N1、N2和N3）。与亲本菌株相比，P1、P2和P3的解磷能力分别提高了56.88%、42.26%和32.15%，而N1、N2和N3的解磷能力分别降低了47.53%、35.27%和30.86%。与亲本菌株相比，三株正向突变菌株分泌的有机酸总量显著增加，负向突变菌株则减少；正向突变菌株的培养基pH显著降低，负向突变菌株则升高。解磷真菌分泌有机酸和降低生长培养基pH的能力与其解磷能力密切相关。突变体分泌有机酸量的变化会改变其酸化和解磷能力。总之，本研究为解磷真菌的探索和应用提供了理论依据和菌株材料。
