1
|
Arenas F, López-García Á, Berná LM, Morte A, Navarro-Ródenas A. Desert truffle mycorrhizosphere harbors organic acid releasing plant growth-promoting rhizobacteria, essentially during the truffle fruiting season. MYCORRHIZA 2022; 32:193-202. [PMID: 35043240 PMCID: PMC8907101 DOI: 10.1007/s00572-021-01067-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 12/28/2021] [Indexed: 06/14/2023]
Abstract
Desert truffle is becoming a new crop in semiarid areas. Climatic parameters and the presence of microorganisms influence the host plant physiology and alter desert truffle production. Desert truffle plants present a typical summer deciduous plant phenology divided into four stages: summer dormancy, autumn bud break, winter photosynthetic activity, and spring fruiting. We hypothesize that the bacterial community associated with desert truffle plants will show a seasonal trend linked to their plant growth-promoting rhizobacteria (PGPR) traits. This information will provide us with a better understanding about its potential role in this symbiosis and possible management implementations. Bacteria were isolated from root-adhering soil at the four described seasons. A total of 417 isolated bacteria were phenotypically and biochemically characterized and gathered by molecular analysis into 68 operational taxonomic units (OTUs). They were further characterized for PGPR traits such as indole acetic acid production, siderophore production, calcium phosphate solubilization, and ACCD (1-amino-cyclopropane-1-carboxilatedeaminase) activity. These PGPR traits were used to infer functional PGPR diversity and cultivable bacterial OTU composition at different phenological moments. The different seasons induced shifts in the OTU composition linked to their PGPR traits. Summer was the phenological stage with the lowest microbial diversity and PGPR functions, whereas spring was the most active one. Among the PGPR traits analyzed, P-solubilizing rhizobacteria were harbored in the mycorrhizosphere during desert truffle fruiting in spring.
Collapse
Affiliation(s)
- Francisco Arenas
- Dpto. Biología Vegetal (Botánica), Facultad de Biología, Universidad de Murcia, CEIR "Campus Mare Nostrum", Campus de Espinardo, 30100, Murcia, Spain
| | - Álvaro López-García
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín-CSIC, Calle Prof. Albareda, 18008, Granada, Spain
- Department of Animal Biology, Plant Biology and Ecology, Universidad de Jaén, Jaén, Spain
- Instituto Interuniversitario de Investigación del Sistema Tierra en Andalucía (IISTA), Av. del Mediterráneo, 18006, Granada, S/N, Spain
| | - Luis Miguel Berná
- Dpto. Biología Vegetal (Botánica), Facultad de Biología, Universidad de Murcia, CEIR "Campus Mare Nostrum", Campus de Espinardo, 30100, Murcia, Spain
| | - Asunción Morte
- Dpto. Biología Vegetal (Botánica), Facultad de Biología, Universidad de Murcia, CEIR "Campus Mare Nostrum", Campus de Espinardo, 30100, Murcia, Spain
| | - Alfonso Navarro-Ródenas
- Dpto. Biología Vegetal (Botánica), Facultad de Biología, Universidad de Murcia, CEIR "Campus Mare Nostrum", Campus de Espinardo, 30100, Murcia, Spain.
| |
Collapse
|
2
|
Querejeta JI, Ren W, Prieto I. Vertical decoupling of soil nutrients and water under climate warming reduces plant cumulative nutrient uptake, water-use efficiency and productivity. THE NEW PHYTOLOGIST 2021; 230:1378-1393. [PMID: 33550582 DOI: 10.1111/nph.17258] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 02/01/2021] [Indexed: 05/21/2023]
Abstract
Warming-induced desiccation of the fertile topsoil layer could lead to decreased nutrient diffusion, mobility, mineralization and uptake by roots. Increased vertical decoupling between nutrients in topsoil and water availability in subsoil/bedrock layers under warming could thereby reduce cumulative nutrient uptake over the growing season. We used a Mediterranean semiarid shrubland as model system to assess the impacts of warming-induced topsoil desiccation on plant water- and nutrient-use patterns. A 6 yr manipulative field experiment examined the effects of warming (2.5°C), rainfall reduction (30%) and their combination on soil resource utilization by Helianthemum squamatum shrubs. A drier fertile topsoil ('growth pool') under warming led to greater proportional utilization of water from deeper, wetter, but less fertile subsoil/bedrock layers ('maintenance pool') by plants. This was linked to decreased cumulative nutrient uptake, increased nonstomatal (nutritional) limitation of photosynthesis and reduced water-use efficiency, above-ground biomass growth and drought survival. Whereas a shift to greater utilization of water stored in deep subsoil/bedrock may buffer the negative impact of warming-induced topsoil desiccation on transpiration, this plastic response cannot compensate for the associated reduction in cumulative nutrient uptake and carbon assimilation, which may compromise the capacity of plants to adjust to a warmer and drier climate.
Collapse
Affiliation(s)
- José Ignacio Querejeta
- Departamento de Conservación de Suelos y Agua, Centro de Edafología y Biología Aplicada del Segura - Consejo Superior de Investigaciones Científicas (CEBAS-CSIC), Murcia, 30100, Spain
| | - Wei Ren
- Departamento de Conservación de Suelos y Agua, Centro de Edafología y Biología Aplicada del Segura - Consejo Superior de Investigaciones Científicas (CEBAS-CSIC), Murcia, 30100, Spain
- Chongqing Key Laboratory of Karst Environment, School of Geographical Sciences, Southwest University, Chongqing, 400715, China
| | - Iván Prieto
- Departamento de Conservación de Suelos y Agua, Centro de Edafología y Biología Aplicada del Segura - Consejo Superior de Investigaciones Científicas (CEBAS-CSIC), Murcia, 30100, Spain
| |
Collapse
|