Analysis of rhizosphere soil microbial diversity and its functions between Dahongpao mother tree and cutting Dahongpao

Abstract

Dahongpao mother tree (Camellia sinensis (L.) O. Ktze) is a representative of Wuyi rock tea. Whether there is a difference in rhizosphere soil microbial diversity and function between asexually propagated cuttings of Dahongpao (PD) and the parent Dahongpao mother tree (MD) has not been reported. In this study, high throughput sequencing technology was used to analyze rhizosphere soil microbial diversity, functions and their relationship with soil available nutrients and enzyme activities in MD and PD. The results showed that available nitrogen, phosphorus and potassium contents and urease, protease, acid phosphatase and sucrase activities of rhizosphere soils in MD were significantly higher than those in PD. Both bacterial and fungal diversity were higher in rhizosphere soils in MD than in PD, and secondly, the bacterial community structure was less stable while the fungal community structure was more stable in PD compared to MD. There were significant differences between MD and PD tea tree rhizosphere soils in 6 genera of characteristic bacteria and 4 genera of characteristic fungi. The results of function and interaction effect analysis showed that the rhizosphere soil available nutrient content and enzyme activities in MD were significantly higher than those in PD, and their contributions mainly originated from Pirellula and Acidisphaera of characteristic bacteria and Alatospora of characteristic fungi. Secondly, MD maybe had a stronger ability to inhibit soil pathogens than PD, with the main contribution coming from Scopulariopsis and Tolypocladium of characteristic fungi. Overall, compared with PD, soil texture in MD was relatively better, and its soil nutrient cycling-related enzyme activities were stronger, which was more favorable to soil nutrient cycling and increased the available nutrient content of the soil, which in turn promoted the growth of tea trees. This study provides an important reference for the planting and management of tea tree cuttings and microbial regulation of tea tree growth.

Keywords: community structure; enzymatic activity; microbial diversity; soil nutrient cycling; tea tree.

Figure 1

Chemical indexes and soil enzyme activity in rhizosphere soil of tea tree. MD: Dahongpao mother tree; PD: Cutting Dahongpao; (A) Analysis of chemical indexes in rhizosphere soil of tea tree; (B) Analysis of enzyme activities in rhizosphere soil of tea tree.

Figure 2

Microbial diversity in rhizosphere soil of tea tree. MD: Dahongpao mother tree; PD: Cutting Dahongpao; (A) Venn diagram analysis of bacterial similarity based on OTUs; (B) α-diversity index analysis of bacterial communities; (C) PCoA analysis of β-diversity of bacterial community; (D) neutral community model analysis of bacterial community; (E) Venn diagram analysis of fungal similarity based on OTUs; (F) α-diversity index analysis of fungal communities; (G) PCoA analysis of β-diversity of fungal communities; (H) neutral community model analysis of fungal communities.

Figure 3

Differential microbial in rhizosphere soil of tea trees. MD: Dahongpao mother tree; PD: Cutting Dahongpao; (A) Bacterial genera with abundance greater than 1% in the rhizosphere soil of MD and PD (abundance not greater than 1% is classified as others); (B) Volcano plot analysis of differential bacteria; (C) Heat map of abundance of differential bacteria; (D) Analysis of number of differential bacteria; (E) Overall abundance analysis of differential bacteria; (F) Fungal genera with abundance greater than 1% in the rhizosphere soil of MD and PD (abundance not greater than 1% is classified as others); (G) Volcano plot analysis of differential fungi; (H) Heat map of abundance of differential fungi; (I) Analysis of number of differential fungi; (J) Overall abundance analysis of differential fungi.

Figure 4

Screening characteristic bacteria and their abundance analysis in rhizosphere soil of tea tree. MD: Dahongpao mother tree; PD: Cutting Dahongpao; (A) MD and PD constructed OPLS-DA model to screen for key differential bacteria; (B) Bubble feature map to screen for key bacteria with more than 90% abundance; (C) TOPSIS analysis of key bacteria to obtain characteristic bacteria that distinguish MD from PD with a weight of 10% or more; (D) Analysis of abundance of characteristic bacteria; (E) qRT-PCR analysis of characteristic bacteria.

Figure 5

Screening characteristic fungi and their abundance analysis in rhizosphere soil of tea tree. MD: Dahongpao mother tree; PD: Cutting Dahongpao; (A) MD and PD constructed OPLS-DA model to screen for key differential fungi; (B) Bubble feature map to screen for key fungi with more than 90% abundance; (C) TOPSIS analysis of key fungi to obtain characteristic fungi that distinguish MD from PD with a weight of 10% or more; (D) Analysis of abundance of characteristic fungi; (E) qRT-PCR analysis of characteristic fungi.

Figure 6

Functional of characteristic bacteria and fungi in the rhizosphere soil of tea tree. MD: Dahongpao mother tree; PD: Cutting Dahongpao; (A) Enrichment of metabolic pathways to characteristic bacterial functions and their intensity analysis; (B) Enrichment of metabolic pathways to characteristic fungal functions and their intensity analysis.

Figure 7

Interaction effects of characteristic microorganisms and functions in rhizosphere soil of tea tree with soil chemical indexes and soil enzyme activities. MD: Dahongpao mother tree; PD: Cutting Dahongpao; (A) Redundancy analysis of characteristic bacteria and their functions with soil chemical indexes, and soil enzyme activities; (B) Redundancy analysis of characteristic fungi and their functions with soil chemical indexes, and soil enzyme activities; (C) Construction of PLS-SEM equations between different indexes. .