Depth-dependent influence of biochar application on the abundance and community structure of diazotrophic under sugarcane growth.

Nyumah Fallah,Ziqin Pang,Ziqi Yang,Zhaoli Lin,Caifang Zhang,Ahmad Yusuf Abubakar,Muhammad Tayyab,Hua Zhang,Americ Allison,Muhammad Riaz

doi:10.1371/journal.pone.0253970

Abstract

Despite progress in understanding diazotrophic distribution in surface soils, few studies have investigated the distribution of diazotrophic bacteria in deeper soil layers. Here, we leveraged high-throughput sequencing (HTS) of nifH genes obtained to assess the influence of biochar amended soil (BC) and control (CK), and soil depths (0–20, 20–40 and 40–60 cm) on diazotrophic abundance and community structures, soil enzyme activities and physio-chemical properties. Multivariate ANOVA analysis revealed that soil depth had profound impact on majority of the soil parameters measured than fertilization. Although soil physio-chemical properties, enzymes activities, diazotrophic genera and enriched operational taxonomic units (OTUs) were significantly influenced across the entire soil profiles, we also observed that BC amended soil significantly increased cane stalk height and weight, nitrate (NO3-), ammonium (NH4+), organic matter (OM), total carbon (TC) and available potassium (AK), and enhanced diazotrophic genera in soil depth 0–20 cm compared to CK treatment. Soil TC, total nitrogen (TN), OM and NH4+ were the major impact factors shifting diazotrophic community structures in soil depth 0–20 cm. Overall, these results were more pronounced in 0–20 cm soil depth in BC than CK treatment.

Highlights

Sugarcane (Saccharum officinarum L.) is an economically vital crop planted in tropical and subtropical regions globally with an annual production of approximately 16 million tons
Biochar amended soil significantly increased (P < 0.05) sugarcane stalk number, stalk weight compared with CK treatment (Fig 1A and 1C)
Soil NO3, NH4+, total carbon (TC), available phosphorus (AP), AK and total nitrogen (TN) significantly decreased with soil depth in all the treatments (Fig 2A, 2B, 2D, 2E, 2G and 2H)

Summary

Introduction

Sugarcane (Saccharum officinarum L.) is an economically vital crop planted in tropical and subtropical regions globally with an annual production of approximately 16 million tons. It contributes considerably to the sugar and biofuel-producing industries [1,2,3]. Fertilization is a crucial agricultural approach that improves plant nutrient storage and simultaneously alters soil attributes and microbial communities [4,5]. In the past few decades, extensive fertilization, especially nitrogen (N) fertilizer, has been used to raise sugarcane production to meet the growing sugar demand [5,6].

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Results

Discussion

Conclusion