Effects of Two Kinds of Commercial Organic Fertilizers on Growth and Rhizosphere Soil Properties of Corn on New Reclamation Land

Abstract

Due to the development of urbanization and industrialization, a large amount of cultivated land resources has been occupied, while new reclamation land could expand the supply of usable land for food security. Organic fertilizers, such as crop residues, biosolids, sheep manure, mushroom residue, and biogas liquid, have been considered as an effective amendment in immature soil to improve its quality. Recently, two kinds of commercial organic fertilizers, pig manure and mushroom residue organic fertilizer (PMMR-OF), and sheep manure organic fertilizer (SM-OF), have been more regularly applied in agriculture production. However, the information available on effect of the two kinds of fertilizers on plant growth and rhizosphere soil properties in immature field is very limited. In order to evaluate PMMR-OF and SM-OF on immature soil, the soil quality and microbial community structure of corn rhizosphere soil samples under the two kinds of organic fertilizers at different concentrations was investigated. The results revealed a significant difference between commercial organic fertilizers (especially SM-OF) and chemical compound fertilizers (CCF) in soil properties and microbial community structure. Indeed, compared with the control based on16S and ITS amplicon sequencing of soil microflora, SM-OF caused a 10.79-19.52%, 4.33-4.39%,and 14.58-29.29% increase in Proteobacteria, Actinobacteria, and Ascomycota, but a 5.82-20.58%, 0.53-24.06%, 10.87-16.79%, 2.69-10.50%, 44.90-59.24%, 8.88-10.98%, and 2.31-21.98% reduction in Acidobacteria, Gemmatimonadetes, Bacteroidetes, Verrucomicrobia, Basidiomycota, Mortierellomycota, and Chytridiomycota, respectively. CCF caused a 24.11%, 23.28%, 38.87%, 19.88%, 18.28%, and 13.89% reduction in Acidobacteria, Gemmatimonadetes, Bacteroidetes, Verrucomicrobia, Basidiomycota, Chytridiomycota, but a 22.77%, 41.28%, 7.88%, and 19.39% increase in Proteobacteria, Actinobacteria, Ascomycota, and Mortierellomycota, respectively. Furthermore, redundancy discriminant analysis of microbial communities and soil properties of PMMR-OF, SM-OF, CCF, and the control treatments indicated that the main variables of bacterial and fungal communities included organic matter content, available P, and available K. Overall, the results of this study revealed significant changes under different fertilizer conditions (PMMR-OF, SM-OF, CCF, under different concentrations) in microbiota and chemical properties of corn soil. Commercial organic fertilizers, particularly SM-OF, can be used as a good amendment for the new reclamation land.

Keywords: commercial compound fertilizer; corn; microbiome; new reclamation land; pig manure and mushroom residue organic fertilizer; sheep manure organic fertilizer; soil property.

Figure 1

The effect of two kinds of commercial organic fertilizers at different concentrations on the OTU distribution of bacteria and fungi. T1–3: PMMR-OF at 0.90, 1.35, and 1.80 kg/m²; T4–6: SM-OF at 0.75, 1.05, and 1.35 kg/m²; T7: CCF at 0.075 kg/m²; CK: the control. Different lowercase letters reveal the significance among different treatments (p < 0.05).

Figure 2

The effect of two kinds of commercial organic fertilizers at different concentrations on Chao1 diversity index (a) and Shannon′s diversity index (b) of bacteria. T1–3: PMMR-OF at 0.90, 1.35, and 1.80 kg/m²; T4–6: SM-OF at 0.75, 1.05, and 1.35 kg/m²; T7: CCF at 0.075 kg/m²; CK: the control. Different lowercase letters reveal the significance among different treatments (p < 0.05).

Figure 3

The effect of two kinds of commercial organic fertilizers at different concentrations on Chao1 diversity index (a) and Shannon′s diversity index (b) of fungi. T1–3: PMMR-OF at 0.90, 1.35, and 1.80 kg/m²; T4–6: SM-OF at 0.75, 1.05, and 1.35 kg/m²; T7: CCF at 0.075 kg/m²; CK: the control. Different lowercase letters reveal the significance among different treatments (p < 0.05).

Figure 4

PCA results of soil bacteria (a) and fungi (b) based on OUT abundance. T1–3: PMMR-OF at 0.90, 1.35, and 1.80 kg/m²; T4–6: SM-OF at 0.75, 1.05, and 1.35 kg/m²; T7: CCF at 0.075 kg/m²; CK: the control.

Figure 5

Relative abundance of bacteria (a) and fungi (b) at the phylum level. T1–3: PMMR-OF at 0.90, 1.35, and 1.80 kg/m²; T4–6: SM-OF at 0.75, 1.05, and 1.35 kg/m²; T7: CCF at 0.075 kg/m²; CK: the control.

Figure 6

Relative abundance of bacteria (a) and fungi (b) at the genus level. T1–3: PMMR-OF at 0.90, 1.35, and 1.80 kg/m²; T4–6: SM-OF at 0.75, 1.0, 5 and 1.35 kg/m²; T7: CCF at 0.075 kg/m²; CK: the control.

Figure 7

Linear discriminant analysis (LDA) effect size (LEfSe) of the bacterial taxa (a), which identifies the most differentially abundant taxa among the two kinds of commercial organic fertilizers at different concentrations treatment. Only taxa with LDA values greater than 4 (p < 0.05) are shown. Hierarchical clustering analysis and heat map at the family level (b). The tree plot represents a clustering analysis of the top 20 bacteria at family levels according to their Pearson correlation coefficient matrix and relative abundance, and the upper tree plot represents a clustering analysis of soil samples according to the Euclidean distance of data. T1–3: PMMR-OF at 0.90, 1.35, and 1.80 kg/m²; T4–6: SM-OF at 0.75, 1.05, and 1.35 kg/m²; T7: CCF at 0.075 kg/m²; CK: the control.

Figure 8

Linear discriminant analysis (LDA) effect size (LEfSe) of the fungal taxa (a), which identifies the most differentially abundant taxa among the two kinds of commercial organic fertilizers at different concentrations treatment. Only taxa with LDA values greater than 4 (p < 0.05) are shown. Hierarchical clustering analysis and heat map at the family level (b). The tree plot represents a clustering analysis of the top 20 fungi at family levels according to their Pearson correlation coefficient matrix and relative abundance, and the upper tree plot represents a clustering analysis of soil samples according to the Euclidean distance of data. T1–3: PMMR-OF at 0.90, 1.35, and 1.80 kg/m²; T4–6: SM-OF at 0.75, 1.05, and 1.35 kg/m²; T7: CCF at 0.075 kg/m²; CK: the control.

Figure 9

Redundancy discriminant analysis (RDA) of the rhizosphere bacterial (a) and fungal (b) community compositions at genus levels with soil physicochemical properties. Gem: Gemmatimonas; Sph: Sphingomonas; Spa: Spartobacteria; Bra: Bradyrhizobium; Sub: Subdivision3; Gai: Gaiella; Fla: Flavisolibacter; Sac: Saccharibacteria; Rey: Reyranella; Lys: Lysobacter; Ram: Ramophialophora; Cha: Chaetomium; Gib: Gibberella; Aur: Aureobasidium; Sor: Sordaria; Zop: Zopfiella; Wai: Waitea; Asc: Ascobolus; Knu: Knufia; Fus: Fusarium; Pod: Podospora; Rhi: Rhizophlyctis; Lae: Laetisaria; Tre: Trechispora. OMC: organic matter contents; TN: total N; AP: available P; AK: available K; exCa: exchangeable Ca; exMg: exchangeable Mg. T1–3: PMMR-OF at 0.90, 1.35 and 1.80 kg/m²; T4–6: SM-OF at 0.75, 1.05 and 1.35 kg/m²; T7: CCF at 0.075 kg/m²; CK: the control.