Changes in phosphorus mobilization and community assembly of bacterial and fungal communities in rice rhizosphere under phosphate deficiency

Abstract

Rhizosphere microorganisms are closely associated with phosphorus (P) uptake in plants and are considered potential agents to mitigate P shortage. However, the mechanisms of rhizospheric microbial community assembly under P deficiency have yet to be elucidated. In this study, bacterial and fungal communities in rice rhizosphere and their P mobilization potential under high (+P) and low (−P) concentrations of P were investigated. Bacterial and fungal community structures were significantly different between −P and +P treatments. And both bacterial and fungal P-mobilizing taxa were enriched in-P treatment; however, the proportion of P-mobilizing agents in the fungal community was markedly greater than that in the bacterial community. A culture experiment confirmed that microbial phosphate solubilizing capacity was significantly higher in −P treatment compared with that in +P treatment. −P treatment lowered bacterial diversity in rice rhizosphere but increased fungal diversity. Further analysis demonstrated that the contribution of deterministic processes in governing bacterial community assembly was strengthened under P deficiency but was largely weakened in shaping the fungal community. These results highlighted that enriching P-mobilizing microbes in the rhizosphere is a vital way for rice to cope with P deficiency, and that fungi contribute considerably to P mobilization in rice rhizosphere. Findings from the study provide novel insights into the assembly of the rhizosphere microbiome under P deficiency and this will facilitate the development of rhizosphere microbial regulation strategies to increase nutrient uptake in plants.

Effect of different straw retention techniques on soil microbial community structure in wheat–maize rotation system

“…Microbial DNA was extracted from each of the 24 samples using a FastDNA Spin Kit for soil (MP Biomedicals, Santa Ana, CA, United States), according to the manufacturer's protocols (Sun et al, 2022 ). The DNA quality and quantity were determined using a NanoDrop 2000 spectrophotometer (Bio-Rad Laboratories Inc., USA.).…”

Substitution of manure for mineral P fertilizers increases P availability by enhancing microbial potential for organic P mineralization in greenhouse soil

“…Soil pH, total carbon (TC), total nitrogen (TN), soil organic matter (SOM), ammonia (NH 4 + –N), nitrate (NO 3 − –N), available P (AP), and total P (TP) were measured as described in a previous study ( Sun et al, 2022 ).…”

“…The microbial dissolving potential for calcium phosphate was determined for each treatment using an incubation method, in accordance with procedures described in our previous study ( Sun et al, 2022 ). Briefly, 1 g soil was added to 90 ml sterilized water and mixed thoroughly.…”

“…Statistical analysis was conducted and figures generated using R (version 4.0.2) as described in our previous study ( Sun et al, 2022 ). The Kruskal–Wallis rank sum test was used to test for significant differences between treatments for each variable.…”

“…VSEARCH (version 2.21.1) (Rognes et al, 2016) was used for bioinformatic analysis of the high-throughput sequencing data Frontiers in Bioengineering and Biotechnology frontiersin.org following the protocols described in previous work (Liang et al, 2020;Sun et al, 2022). The paired-end reads were first merged, and low-quality and chimeric reads were then removed.…”