TY - JOUR

T1 - Long-term straw and plastic film mulching have divergent effects on maize rhizosphere enzyme activity and bacterial community structure

AU - Li, Yan

AU - Zhang, Xuechen

AU - Yang, Na

AU - Hao, Hongyu

AU - Bilyera, Nataliya

AU - Zhang, Xucheng

AU - Li, Tingliang

AU - Yue, Shanchao

AU - Zhai, Bingnian

AU - Zamanian, Kazem

AU - Li, Ziyan

AU - Razavi, Bahar S.

N1 - This work was supported by the National Natural Science Foundation of China (42177342), the Foreign Expert Introduction Program sponsored by the Ministry of Science and Technology (G2022172039L), Shaanxi Province Key Research and Development Projects (2022ZDLNY02-01), the Major Science and Technology Projects in Shaanxi Province (2020zdzx03-02-01), Foundation of Key Laboratory of High-Water Utilization on Dryland of Gansu Province (HNSJJ-2021), the Fundamental Research Funds for the Central Universities (2452023091, 2452022026).

PY - 2024/4/15

Y1 - 2024/4/15

N2 - Mulching is widely adopted in arid regions to improve soil environment and crop productivity. However, our understanding of the underlying mechanisms of such improvements from enzyme activity and rhizosphere microbial community structure perspectives remain poor. To fill the gap, soil zymography was coupled with high-throughput sequencing to investigate enzyme activities and bacterial community structure in a 10-year field experiment in a semi-arid region. We examined the effects of two mulching measures (plastic film mulching [FM] and straw mulching [SM], with no mulching as the control [CK]) on the maize rhizosphere extent of β-glucosidase and leucine aminopeptidase activities and the abundance of the bacterial genes encoding these two enzymes. The enzyme activity in the SM and FM measures was higher compared to the CK measures (P < 0.05). SM had higher influence than FM on β-glucosidase activity and its rhizosphere extent. This was related to the increase in soil organic carbon (SOC) content and the stable bacterial community structure and interactions under SM. In contrast, leucine aminopeptidase activity was the highest under FM due to the higher soil temperature and moisture content under FM which further intensified nutrient competition among microorganisms or between microorganisms and plants. In addition, Proteobacteria and Acidobacteria were the major contributors to β-glucosidase activity despite their genes encoding β-glucosidase not increasing under SM. Conversely, the copy number of genes encoding leucine aminopeptidase and the genes encoded by Proteobacteria (the main contributor) decreased under FM. Therefore, total gene number is not a stable indicator of microbial function (such as enzyme activity) and cannot explain enzyme activity adequately. Overall, this study establishes a connection between rhizosphere enzyme activity and bacterial communities, revealing the mechanisms by which changes in environmental nutrient supply and bacterial community composition under straw mulching and plastic film mulching measures lead to variations in enzyme efficiency.

AB - Mulching is widely adopted in arid regions to improve soil environment and crop productivity. However, our understanding of the underlying mechanisms of such improvements from enzyme activity and rhizosphere microbial community structure perspectives remain poor. To fill the gap, soil zymography was coupled with high-throughput sequencing to investigate enzyme activities and bacterial community structure in a 10-year field experiment in a semi-arid region. We examined the effects of two mulching measures (plastic film mulching [FM] and straw mulching [SM], with no mulching as the control [CK]) on the maize rhizosphere extent of β-glucosidase and leucine aminopeptidase activities and the abundance of the bacterial genes encoding these two enzymes. The enzyme activity in the SM and FM measures was higher compared to the CK measures (P < 0.05). SM had higher influence than FM on β-glucosidase activity and its rhizosphere extent. This was related to the increase in soil organic carbon (SOC) content and the stable bacterial community structure and interactions under SM. In contrast, leucine aminopeptidase activity was the highest under FM due to the higher soil temperature and moisture content under FM which further intensified nutrient competition among microorganisms or between microorganisms and plants. In addition, Proteobacteria and Acidobacteria were the major contributors to β-glucosidase activity despite their genes encoding β-glucosidase not increasing under SM. Conversely, the copy number of genes encoding leucine aminopeptidase and the genes encoded by Proteobacteria (the main contributor) decreased under FM. Therefore, total gene number is not a stable indicator of microbial function (such as enzyme activity) and cannot explain enzyme activity adequately. Overall, this study establishes a connection between rhizosphere enzyme activity and bacterial communities, revealing the mechanisms by which changes in environmental nutrient supply and bacterial community composition under straw mulching and plastic film mulching measures lead to variations in enzyme efficiency.

KW - Bacterial community

KW - Enzyme kinetics

KW - Long-term mulching

KW - Rhizosphere microbiome

KW - Soil zymography

UR - http://www.scopus.com/inward/record.url?scp=85182902651&partnerID=8YFLogxK

U2 - 10.1016/j.agee.2024.108894

DO - 10.1016/j.agee.2024.108894

M3 - Article

VL - 364

JO - Agriculture, Ecosystems and Environment

JF - Agriculture, Ecosystems and Environment

SN - 0167-8809

M1 - 108894

ER -