Diazotrophic population and soil nitrogen dynamics following coapplication of biochar with inorganic fertilizer in the humid tropics

Halmi, Muhammad Farid Azlan and Simarani, Khanom (2021) Diazotrophic population and soil nitrogen dynamics following coapplication of biochar with inorganic fertilizer in the humid tropics. Bragantia, 80. ISSN 0006-8705, DOI https://doi.org/10.1590/1678-4499.20210017.

Full text not available from this repository.

Abstract

Nutrient loss from the weathering process is a major challenge for tropical agriculture. Biochar with nutrient retention capacity has been proposed as an amendment to retain plant-available nutrients. Meanwhile, information on diazotrophic population responses to biochar application in the humid tropics is still poorly explored. A field study was carried out over three cropping cycles of maize in a typic paleudults of Peninsular Malaysia. During the first cropping cycle, the soil was amended with palm kernel shell biochar (PK), rice husk biochar (RH), palm kernel biochar with fertilizer (FPK), rice husk biochar with fertilizer (FRH), fertilizer (F), and control soil (C). Soil samples were taken at each harvesting stage and analyzed for pH, cation exchange capacity (CEC), total N, ammonium (NH4+-N), nitrate (NO3--N), microbial biomass N, and urease activity. Total and active diazotrophs were quantified from soil DNA and RNA, respectively, employing quantitative polymerase chain reaction (qPCR) amplification of the nifH gene. Palm kernel shell and rice husk biochars maintained a significant NH4+-N and NO3--N, respectively, during the second cropping cycle. Both biochars promote the total and active diazotrophic population. A detrimental impact on the nifH transcript was detected from fertilization even when biochar was co-amended. Two possible land management options for tropical soil were proposed from the overall data. First, the application of fertilizer with biochar can reduce N loss against weathering. Second, the application of biochar alone may improve biological N-2 fixation in tropical soils.

Item Type: Article
Funders: Universiti Malaya [RP023B-16SUS PG057-2013A]
Uncontrolled Keywords: Active microbial population; Microbial soil enzyme; Highly weathered soil; nifH; Nitrogen retention; qPCR
Subjects: Q Science > QE Geology
S Agriculture > S Agriculture (General)
Divisions: Faculty of Science > Institute of Biological Sciences
Depositing User: Ms Zaharah Ramly
Date Deposited: 14 Apr 2022 01:35
Last Modified: 14 Apr 2022 01:35
URI: http://eprints.um.edu.my/id/eprint/26933

Actions (login required)

View Item View Item