Effects of Streptomyces sp. HU2014 inoculation on wheat
发布日期：2024-04-16 21:06 浏览次数：
Effects of Streptomyces sp. HU2014 inoculation on wheat growth and rhizosphere microbial diversity under hexavalent chromium stress , , , , , ,
Abstract
Wheat (Triticum aestivum L.) is a major foodstuff for over 40% of the world’s population. However, hexavalent chromium [Cr(VI)] in contaminated soil significantly affects wheat production and its ecological environment. Streptomyces sp. HU2014 was first used to investigate the effects of Cr (VI) stress on wheat growth. We analyzed the Cr(VI) concentration, physicochemical properties of wheat and soil, total Cr content, and microbial community structures during their interactions. HU2014 reduced the toxicity of Cr(VI) and promoted wheat growth by increasing total nitrogen, nitrate nitrogen, total phosphorus, and Olsen-phosphorus in Cr(VI)-contaminated soil. These four soil variables had strong positive effects on two bacterial taxa, Proteobacteria and Bacteroidota, in the HU2014 treatments. In addition, the level of the dominant Proteobacteria positively correlated with the total Cr content in the soil. Among the fungal communities, which had weaker correlations with soil variables compared with bacterial communities, Ascomycota was the most abundant. Our findings suggest that HU2014 can promote the phytoremediation of Cr(VI)-contaminated soil.
Fig. 1. Growth of HU2014 at different Cr(VI) concentrations (A), change of Cr(VI) concentration with HU2014 presence (B), and influence of Cr(VI) on ID production by HU2014 (C). Con., concentration; ID, Indole derivative.
Fig. 2. Wheat physicochemical properties (A–E) and TCr uptake in wheat shoots and roots (F). CK, the untreated soil as a control; CCr, the soil with Cr(VI) addition; S, the soil with HU2014 inoculation; SCr, the soil with HU2014 inoculation plus Cr(VI) addition; CAT, catalase; POD, peroxidase; MDA, malondialdehyde; TCr, total Cr content. Different lowercase letters indicate significance among the treatments in A–E and among the treatments within the shoot and root groups for F (P < 0.05; Tukey’s test).
Fig. 3. Bacterial and fungal alpha diversity indices across treatments (*P < 0.05; **P < 0.01; Tukey’s test). CK, CCr, S, and SCr represent the control check soil, soil with 30 mg/ kg Cr(VI) addition, soil with HU2014 inoculation, and soil with HU2014 inoculation plus 30 mg/ kg Cr(VI) addition, respectively.
Fig. 4. Relative abundance of microbial communities across treatments. CK, CCr, S, and SCr represent the control check soil, soil with 30 mg/ kg Cr(VI) addition, soil with HU2014 inoculation, and soil with HU2014 inoculation plus 30 mg/ kg Cr(VI) addition, respectively.
