Microbial phosphorus(P)turnover is critical in C utilization efficiency in agroecosystems.It is therefore necessary to understand the P mobilization processes occurring during P fertilization in order to ensure both c...Microbial phosphorus(P)turnover is critical in C utilization efficiency in agroecosystems.It is therefore necessary to understand the P mobilization processes occurring during P fertilization in order to ensure both crop yield and environmental quality.Here,we established a controlled pot experiment containing soil amended with three different levels of starter P fertilizer and collected soil samples after 30,60,and 90 days of incubation.Quantitative microbial element cycling(QMEC)smart chip technology and 16S rRNA gene sequencing were used to investigate functional gene structures involved in carbon,nitrogen and P cycling and the bacterial community composition of the collected samples.Although P fertilization did not significantly affect the structure of the soil microbial community,some rare microbiota were changed in particular phosphorus-solubilizing bacteria were enriched at the high P fertilization level,suggesting that the rare taxa make an important contribution to P turnover.P fertilization also altered the functional gene structure,and high P concentrations enhanced the functional gene diversity and abundance.Partial redundancy analysis further revealed that changes in rare taxa and functional genes of soil microorganisms drive the alteration of soil P pools.These findings extend our understanding of the microbial mechanisms of P turnover.展开更多
Antioxidants are highly beneficial to human health, and their accumulation in lettuce, one of the most popular leafy vegetables, depends on both genetic and environmental factors. Nitrogen(N) availability plays an ess...Antioxidants are highly beneficial to human health, and their accumulation in lettuce, one of the most popular leafy vegetables, depends on both genetic and environmental factors. Nitrogen(N) availability plays an essential role in regulating antioxidant accumulation, but the influence of genotype × N interactions on the antioxidant qualities of lettuce is poorly understood. Therefore, the present study investigated the variation of growth and antioxidant qualities of 20 lettuce(Lactuca sativa L.) genotypes(10 green lettuce genotypes and 10 red lettuce genotypes) under limited N(low N, LN) conditions and standard N(high N, HN) conditions. For all 20 genotypes, LN conditions reduced shoot(i.e., leaf) growth, but increased plant concentrations of vitamin C,glutathione, and phenolic compounds, with the exception of carotenoids, compared with HN conditions. Because of reduced biomass under LN conditions, not all lettuce genotypes exhibited increased antioxidant yields or total antioxidant capacity yield. The variation in antioxidant quality was primarily genetically determined. Generally, the green lettuce genotypes exhibited more pronounced increases in antioxidant yields and total antioxidant capacity yield than the red lettuce genotypes under LN conditions. These results suggest that even though LN conditions generally tend to improve the antioxidant qualities of lettuce, the extent of this effect is highly dependent on genotype. Therefore, genotype should be given priority in future studies that aim to improve antioxidant qualities in lettuce through N management.展开更多
Organic fertilization may influence soil carbon−iron(C-Fe)cycling and enhance phosphorus(P)availability,yet the direct connection between soil organic matter molecules and iron-reducing processes in long-term fertiliz...Organic fertilization may influence soil carbon−iron(C-Fe)cycling and enhance phosphorus(P)availability,yet the direct connection between soil organic matter molecules and iron-reducing processes in long-term fertilized paddy soils remains underexplored.In this study,we conducted a microcosm experiment using paddy soils treated with six distinct fertilization regimes involving varying P and organic matter inputs up to five years.We assessed P activation under reflooding conditions,evaluated Fe reduction,and characterized dissolved organic matter(DOM)at the molecular level using Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS),alongside profiling soil microbial community composition via high-throughput sequencing.Our findings revealed that after 25 days of reflooding,soil Olsen-P content increased by an average of 73%compared to its initial state,showing a strong correlation with the Fe reduction process.Specifically,treatments involving pig manure application exhibited higher Fe reduction rates and enhanced P activation,highlighting the role of organic matter in facilitating Fe reduction.Examination of Fe-reducing microorganisms revealed that their relative abundance was decoupled from Fe reduction and P release rates,potentially due to limitations of lower soil organic matter content.Further analysis of DOM composition and network structures suggested that high-molecular-weight DOM,particularly lignin,acted as key resources for Fe-reducing microbes,thereby driving Fe reduction and promoting P release.Overall,our study highlights the crucial role of soil DOM in enabling microbial-driven Fe reduction and enhancing P availability,providing insights valuable for sustainable agricultural practices.展开更多
基金This work was supported by the National Key Research and Development Program of China(No.2017YFD0200201)the Natural Science Foundation of China(No.21922608)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB15020402).
文摘Microbial phosphorus(P)turnover is critical in C utilization efficiency in agroecosystems.It is therefore necessary to understand the P mobilization processes occurring during P fertilization in order to ensure both crop yield and environmental quality.Here,we established a controlled pot experiment containing soil amended with three different levels of starter P fertilizer and collected soil samples after 30,60,and 90 days of incubation.Quantitative microbial element cycling(QMEC)smart chip technology and 16S rRNA gene sequencing were used to investigate functional gene structures involved in carbon,nitrogen and P cycling and the bacterial community composition of the collected samples.Although P fertilization did not significantly affect the structure of the soil microbial community,some rare microbiota were changed in particular phosphorus-solubilizing bacteria were enriched at the high P fertilization level,suggesting that the rare taxa make an important contribution to P turnover.P fertilization also altered the functional gene structure,and high P concentrations enhanced the functional gene diversity and abundance.Partial redundancy analysis further revealed that changes in rare taxa and functional genes of soil microorganisms drive the alteration of soil P pools.These findings extend our understanding of the microbial mechanisms of P turnover.
基金This work was supported by the National Natural Science Foundation of China(No.30971859)the National Key Research and Development Program of China(No.2016YFD0200103).
文摘Antioxidants are highly beneficial to human health, and their accumulation in lettuce, one of the most popular leafy vegetables, depends on both genetic and environmental factors. Nitrogen(N) availability plays an essential role in regulating antioxidant accumulation, but the influence of genotype × N interactions on the antioxidant qualities of lettuce is poorly understood. Therefore, the present study investigated the variation of growth and antioxidant qualities of 20 lettuce(Lactuca sativa L.) genotypes(10 green lettuce genotypes and 10 red lettuce genotypes) under limited N(low N, LN) conditions and standard N(high N, HN) conditions. For all 20 genotypes, LN conditions reduced shoot(i.e., leaf) growth, but increased plant concentrations of vitamin C,glutathione, and phenolic compounds, with the exception of carotenoids, compared with HN conditions. Because of reduced biomass under LN conditions, not all lettuce genotypes exhibited increased antioxidant yields or total antioxidant capacity yield. The variation in antioxidant quality was primarily genetically determined. Generally, the green lettuce genotypes exhibited more pronounced increases in antioxidant yields and total antioxidant capacity yield than the red lettuce genotypes under LN conditions. These results suggest that even though LN conditions generally tend to improve the antioxidant qualities of lettuce, the extent of this effect is highly dependent on genotype. Therefore, genotype should be given priority in future studies that aim to improve antioxidant qualities in lettuce through N management.
基金supported by the National Natural Science Foundation of China(Grant Nos.42477335,42077088)the Zhejiang Province“Agriculture,Rural Areas,Rural People and Nine Institutions”Science and Technology Collaboration Program(Grant No.2023SNJF039)X.P.L.was supported by a scholarship from the China Scholarship Council.
文摘Organic fertilization may influence soil carbon−iron(C-Fe)cycling and enhance phosphorus(P)availability,yet the direct connection between soil organic matter molecules and iron-reducing processes in long-term fertilized paddy soils remains underexplored.In this study,we conducted a microcosm experiment using paddy soils treated with six distinct fertilization regimes involving varying P and organic matter inputs up to five years.We assessed P activation under reflooding conditions,evaluated Fe reduction,and characterized dissolved organic matter(DOM)at the molecular level using Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS),alongside profiling soil microbial community composition via high-throughput sequencing.Our findings revealed that after 25 days of reflooding,soil Olsen-P content increased by an average of 73%compared to its initial state,showing a strong correlation with the Fe reduction process.Specifically,treatments involving pig manure application exhibited higher Fe reduction rates and enhanced P activation,highlighting the role of organic matter in facilitating Fe reduction.Examination of Fe-reducing microorganisms revealed that their relative abundance was decoupled from Fe reduction and P release rates,potentially due to limitations of lower soil organic matter content.Further analysis of DOM composition and network structures suggested that high-molecular-weight DOM,particularly lignin,acted as key resources for Fe-reducing microbes,thereby driving Fe reduction and promoting P release.Overall,our study highlights the crucial role of soil DOM in enabling microbial-driven Fe reduction and enhancing P availability,providing insights valuable for sustainable agricultural practices.
