Isolation and characterization of phosphofungi, and screening of their plant growth-promoting activities

Abstract

Rhizospheric microorganisms can increase phosphorus availability in the soil. In this regard, the ability of phosphofungi to dissolve insoluble phosphorus compounds is greater than that of phosphate-solubilizing bacteria. The aim of the current study was to identify efficient phosphofungi that could be developed as commercial microbial agents. Among several phosphate-solubilizing fungal isolates screened, strain CS-1 showed the highest phosphorus-solubilization ability. Based on phylogenetic analysis of the internal transcribed spacer region sequence, it was identified as Aspergillus niger. High-performance liquid chromatography analysis revealed that the mechanism of phosphorus solubilization by CS-1 involved the synthesis and secretion of organic acids, mainly oxalic, tartaric, and citric acids. Furthermore, strain CS-1 exhibited other growth-promoting abilities, including efficient potassium release and degradation of crop straw cellulose. These properties help to returning crop residues to the soil, thereby increasing nutrient availability and sustaining organic matter concentration therein. A pot experiment revealed that CS-1 apparently increased the assessed biometric parameters of wheat seedlings, implying the potential of this strain to be developed as a commercial microbial agent. We used Illumina MiSeq sequencing to investigate the microbial community composition in the rhizosphere of uninoculated wheat plants and wheat plants inoculated with the CS-1 strain to obtain insight into the effect of the CS-1 strain inoculation. The data clearly demonstrated that CS-1 significantly reduced the content of pathogenic fungi, including Gibberella, Fusarium, Monographella, Bipolaris, and Volutella, which cause soil-borne diseases in various crops. Strain CS-1 may hence be developed into a microbial agent for plant growth improvement.Electronic supplementary materialThe online version of this article (10.1186/s13568-018-0593-4) contains supplementary material, which is available to authorized users.

Effects of Enterobacter cloacae HG-1 on the Nitrogen-Fixing Community Structure of Wheat Rhizosphere Soil and on Salt Tolerance

“…Ten pots were treated with the same amount of sterile Milli-Q water (20 ml) and marked as the blank control group, CK ( Wei et al., 2017 ). Randomized complete block design was used in this study ( Wang et al., 2018 ). After 30 days of cultivation, wheat plants were taken out of the pots and plant biomass was measured.…”

Peer Review #1 of "Long-term effects of straw and straw-derived biochar on soil aggregation and fungal community in a rice–wheat rotation system (v0.1)"

“…Therefore, CO 2 emission variation in CS and CB needs further exploration. Gibberella and Monographella, which cause soil-borne diseases in crops (Tatagiba et al 2016;Wang et al 2018;Yan et al 2018), were lower in CS and CB in the 0-20 cm layer, with their levels in CB exhibiting significant differences relative to those in CF (p < 0.05). These reduced pathogenic fungal contents might lessen the probability of morbidity.…”

Screening of Phosphate-Solubilizing Fungi From Air and Soil in Yunnan, China: Four Novel Species in Aspergillus, Gongronella, Penicillium, and Talaromyces

“…actinomyces, bacteria, fungi, and yeasts have been screened for phosphate solubilization. They were shown to enhance the solubilization of insoluble P compounds ( Gizaw et al, 2017 ; Nandimath et al, 2017 ; Mohamad et al, 2018 ; Wang et al, 2018 ; Chen and Liu, 2019 ; Liu et al, 2019 ). For fungi, Rhizopus stolonifer var.…”

“…Some studies of PSF identified fungal species names based on morphology, highest nucleotide similarity in MegaBLAST searches of NCBI’s GenBank nucleotide database and/or phylogenetic analysis of ITS sequence data ( Nelofer et al, 2015 ; Wang et al, 2018 ; Zhang et al, 2018 , Supplementary Table S5 ). However, these are insufficient to determine the species names, especially within species complexes ( Samson et al, 2014 ; Doilom et al, 2017 ; Hyde et al, 2020a , b ).…”