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The Relationship between Ectomycorrhizal Fungi, Nitrogen Deposition, and Pinus massoniana Seedling Nitrogen Transporter Gene Expression and Nitrogen Uptake Kinetics. J Fungi (Basel) 2022; 9:jof9010065. [PMID: 36675886 PMCID: PMC9862668 DOI: 10.3390/jof9010065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/19/2022] [Accepted: 12/28/2022] [Indexed: 01/03/2023] Open
Abstract
Analyzing the molecular and physiological processes that govern the uptake and transport of nitrogen (N) in plants is central to efforts to fully understand the optimization of plant N use and the changes in the N-use efficiency in relation to changes in atmospheric N deposition changes. Here, a field experiment was conducted using the ectomycorrhizal fungi (EMF), Pisolithus tinctorius (Pt) and Suillus grevillei (Sg). The effects of N deposition were investigated using concentrations of 0 kg·N·hm-2a-1 (N0), a normal N deposition of 30 kg·N·hm-2a-1 (N30), a moderate N deposition of 60 kg·N·hm-2a-1 (N60), and a severe N deposition of 90 kg·N·hm-2a-1 (N90), with the goal of examining how these factors impacted root activity, root absorbing area, NH4+ and NO3- uptake kinetics, and the expression of ammonium and nitrate transporter genes in Pinus massoniana seedlings under different levels of N deposition. These data revealed that EMF inoculation led to increased root dry weight, activity, and absorbing area. The NH4+ and NO3- uptake kinetics in seedlings conformed to the Michaelis-Menten equation, and uptake rates declined with increasing levels of N addition, with NH4+ uptake rates remaining higher than NO3- uptake rates for all tested concentrations. EMF inoculation was associated with higher Vmax values than were observed for non-mycorrhizal plants. Nitrogen addition resulted in the upregulation of genes in the AMT1 family and the downregulation of genes in the NRT family. EMF inoculation under the N60 and N90 treatment conditions resulted in the increased expression of each of both these gene families. NH4+ and NO3- uptake kinetics were also positively correlated with associated transporter gene expression in P. massoniana roots. Together, these data offer a theoretical foundation for EMF inoculation under conditions of increased N deposition associated with climate change in an effort to improve N absorption and transport rates through the regulation of key nitrogen transporter genes, thereby enhancing N utilization efficiency and promoting plant growth. Synopsis: EMF could enhance the efficiency of N utilization and promote the growth of Pinus massoniana under conditions of increased N deposition.
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Zhou J, Gube M, Holz M, Song B, Shan I, Shi L, Kuzyakov Y, Dippold MA, Pausch J. Ectomycorrhizal and non-mycorrhizal rhizosphere fungi increase root-derived C input to soil and modify enzyme activities: A 14 C pulse labelling of Picea abies seedlings. PLANT, CELL & ENVIRONMENT 2022; 45:3122-3133. [PMID: 35909089 DOI: 10.1111/pce.14413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 07/11/2022] [Accepted: 07/29/2022] [Indexed: 06/15/2023]
Abstract
Consequences of interactions between ectomycorrhizal fungi (EcMF) and non-mycorrhizal rhizosphere fungi (NMRF) for plant carbon (C) allocation belowground and nutrient cycling in soil remain unknown. To address this topic, we performed a mesocosm study with Norway spruce seedlings [Picea abies (L.) H. Karst] inoculated with EcMF, NMRF, or a mixture of both (MIX). 14 CO2 pulse labelling of spruce was applied to trace and visualize the 14 C incorporation into roots, rhizohyphosphere and hyphosphere. Activities and localization of enzymes involved in the C, nitrogen (N) and phosphorus (P) cycling were visualized using zymography. Spruce seedlings inoculated with EcMF and NMRF allocated more C to soils (EcMF: 10.7%; NMRF: 3.5% of total recovered C) compared to uninoculated control seedlings. The 14 C activity in the hyphosphere was highest for EcMF and lowest for NMRF. In the presence of both, NMRF and EcMF (MIX), the 14 C activity was 64% lower compared with EcMF inoculation alone. This suggests a suppressed C allocation via EcMF likely due to the competition between EcMF and NMRF for N and P. Furthermore, we observed 57% and 49% higher chitinase and leucine-aminopeptidase activities in the rhizohyphosphere of EcMF compared to the uninoculated control, respectively. In contrast, β-glucosidase activity (14.3 nmol cm-2 h-1 ) was highest in NMRF likely because NMRF consumed rhizodeposits efficiently. This was further supported by that enzyme stoichiometry in soil with EcMF shifted to a higher investment of nutrient acquisition enzymes (e.g., chitinase, leucine-aminopeptidase, acid phosphatase) compared to NMRF inoculation, where investment in β-glucosidase increased. In conclusion, the alleviation of EcMF from C limitation promotes higher activities of enzymes involved in the N and P cycle to cover the nutrient demand of EcMF and host seedlings. In contrast, C limitation of NMRF probably led to a shift in investment towards higher activities of enzymes involved in the C cycle.
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Affiliation(s)
- Jie Zhou
- Biogeochemistry of Agroecosystems, Department of Crop Science, Georg August University of Göttingen, Göttingen, Germany
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, China
| | - Matthias Gube
- Department of Soil Science of Temperate Ecosystems, Department of Agricultural Soil Science, Georg August University of Göttingen, Göttingen, Germany
| | - Maire Holz
- Group of Isotope Biogeochemistry and Gas Fluxes, Leibniz Centre for Agricultural Landscape Research (ZALF) e.V., Müncheberg, Germany
| | - Bin Song
- Forest Botany and Tree Physiology, Georg August University of Göttingen, Göttingen, Germany
| | - Immo Shan
- Forest Botany and Tree Physiology, Georg August University of Göttingen, Göttingen, Germany
| | - Lingling Shi
- Department of Economic Plants and Biotechnology, Yunnan Key Laboratory For Wild Plant Resources, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
- Centre for Mountain Futures (CMF), Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Yakov Kuzyakov
- Department of Soil Science of Temperate Ecosystems, Department of Agricultural Soil Science, Georg August University of Göttingen, Göttingen, Germany
- Agro-Technological Institute, Peoples Friendship University of Russia (RUDN University), Moscow; Institute of Environmental Sciences, Kazan Federal University, Kazan, Russia
| | - Michaela A Dippold
- Biogeochemistry of Agroecosystems, Department of Crop Science, Georg August University of Göttingen, Göttingen, Germany
- Geo-Biosphere Interactions, Department of Geosciences Faculty of Sciences, University of Tuebingen, Tuebingen, Germany
| | - Johanna Pausch
- Department of Agroecology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
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Pengfei S, Yafei S, Lijun W, Tian C, Meng Z, Wenfa X, Ruimei C. Photosynthetic product allocations of Pinus massoniana seedlings inoculated with ectomycorrhizal fungi along a nitrogen addition gradient. FRONTIERS IN PLANT SCIENCE 2022; 13:948676. [PMID: 36035728 PMCID: PMC9412729 DOI: 10.3389/fpls.2022.948676] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 07/22/2022] [Indexed: 05/13/2023]
Abstract
Quantifying the allocation of photosynthetic products among different carbon (C) pools is critical for understanding and predicting plant C turnover response to climate change. A field experiment with ectomycorrhizal fungi (EMF) and nitrogen (N) was established to investigate the effects on allocation of photosynthetic products in Pinus massoniana (Lamb.) seedlings given increased N deposition. Seedlings were subjected to N addition and symbiosis with EMF, and the short-term allocation of a 13C photosynthetic pulse into leaves, branches, stems, roots, and soil was traced. Photosynthetic rate and root respiration were measured. It was found that N addition changed the allocation pattern of photosynthetic products in various organs of P. massoniana. Furthermore, N addition, mycorrhizal symbiosis, and interaction of N and EMF, all increased the amount of C produced by photosynthesis. N application less than 60 kg N hm-1 a-1 could promote the transfer and allocation of photosynthetic products in P. massoniana organs, which peaks at 60 kg N hm-1 a-1, and the highest N treatment began to decrease at 90 kg N hm-1 a-1. EMF inoculation could expand the absorption area of plant roots to obtain more nutrients and synthesize more C and N compounds for promoting the growth of itself and the host plant, improving the net photosynthetic rate and the distribution of C produced by photosynthesis in various organs. This forms a benign C and N cycle, thereby reducing the effect of high N addition on plants. The optimal N addition concentration was 60 kg N hm-1 a-1, and the optimal EMF was Pt, which provides a theoretical basis for inoculating EMF during increasing N deposition in the future climate change scenario. This enables plants to distribute more photosynthetic products to their roots, thus affecting their own C distribution for promoting growth.
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Affiliation(s)
- Sun Pengfei
- Chinese Academy of Forestry, Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Beijing, China
| | - Shen Yafei
- Chinese Academy of Forestry, Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Beijing, China
- Co-innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
| | - Wang Lijun
- Chinese Academy of Forestry, Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Beijing, China
| | - Chen Tian
- Chinese Academy of Forestry, Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Beijing, China
| | - Zhang Meng
- Chinese Academy of Forestry, Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Beijing, China
| | - Xiao Wenfa
- Chinese Academy of Forestry, Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Beijing, China
- Co-innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
| | - Cheng Ruimei
- Chinese Academy of Forestry, Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Beijing, China
- Co-innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, China
- *Correspondence: Cheng Ruimei,
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