Ancient History – Present: Medicinal plants are used for various ailments, with some compounds later discovered to be synthesized by their microbiome. (Applebaum et al., 2022)
Undetermined – Present: The understanding of how plants manipulate their habitats through exudation is not fully understood, including whether it’s truly advantageous or how it’s controlled. (Plant root exudates – Wikipedia)
Undetermined – Present: Most microbes have incompatible interactions with plants. (Plant root exudates – Wikipedia)
1904: The Birth of “Rhizosphere”
1904: German plant physiologist Lorenz Hiltner coins the term “rhizosphere” to describe the region of soil surrounding plant roots influenced by chemicals released from the roots and populated by microorganisms. (Rhizosphere – Wikipedia; Biology Notes Online; How Does the Rhizosphere Effect Influence Plant Growth and Soil Health?)
Early 20th Century – Late 20th Century: Initial Discoveries and Concepts
1976: Walker and Syers publish on the fate of phosphorus during pedogenesis, contributing to the understanding of P cycling. (Dijkstra et al., 2013)
1978: Lauenroth et al. conduct a study suggesting plants and microbes in a semiarid grassland may be more limited by nitrogen than phosphorus. (Dijkstra et al., 2013)
1981: McGill and Cole highlight that the supply of nitrogen and phosphorus to plants is decoupled in many soil types. (Dijkstra et al., 2013)
1984: Sims and Dunigan observe diurnal and seasonal variations in nitrogenase activity of rice roots, mimicking plant behavior and supplying nitrogen when demand is high. (Rhizosphere – Wikipedia)
1985: Ingham et al. show that predation by bacterial-feeding nematodes influences nitrogen availability and plant growth, and increases bacterial populations. (Rhizosphere – Wikipedia)
1988: Atzorn et al. first characterize gibberellins (GAs) in Rhizobium meliloti. (Hakim et al., 2021)
1988: Weller publishes on the biological control of soilborne plant pathogens using bacteria in the rhizosphere. (Rhizosphere – Wikipedia)
1990: Lerouge et al. determine that the symbiotic host-specificity of Rhizobium meliloti is determined by a sulphated and acylated glucosamine oligosaccharide signal. (Jamil et al., 2022)
1991: Vitousek and Howarth discuss nitrogen limitation on land and in the sea. (Dijkstra et al., 2013)
1993: Schlten and Leinweber use pyrolysis–field ionization mass spectrometry to study organic compounds in agricultural soils. (Rhizosphere – Wikipedia)
1993: Mary et al. show that different organic compounds from rhizodeposition have variable effects on priming. (Dijkstra et al., 2013)
1996: Cheng reports the observation of a negative priming effect in planted soil compared to unplanted soil. (Dijkstra et al., 2013)
1997: Dunne et al. demonstrate the biological control of Pythium ultimum by Stenotrophomonas maltophilia W81 through extracellular proteolytic activity. (Jamil et al., 2022)
1997: Hungate et al. study the fate of carbon in grassland under carbon dioxide enrichment. (Dijkstra et al., 2013)
1997: Kaye and Hart discuss competition for nitrogen between plants and soil microorganisms. (Rhizosphere – Wikipedia)
1998: Grayston et al. study the selective influence of plant species on microbial diversity in the rhizosphere. (Rhizosphere – Wikipedia)
1998: Jones reviews organic acids in the rhizosphere. (Rhizosphere – Wikipedia)
1998: McCann et al. explore weak trophic interactions and the balance of nature. (Rhizosphere – Wikipedia)
1999: Cheng discusses rhizosphere feedbacks under elevated CO2. (Dijkstra et al., 2013)
1999: Gregory and Hinsinger review new approaches to studying chemical and physical changes in the rhizosphere. (Rhizosphere – Wikipedia)
2000s: Expanding Understanding and Climate Change Focus
2000: Czarnes et al. show how root and microbial-derived mucilages affect soil structure and water transport. (Rhizosphere – Wikipedia)
2000: Yang and Crowley study rhizosphere microbial community structure in relation to root location and plant iron nutritional status. (Jamil et al., 2022)
2001: Owen and Jones study competition for amino acids between wheat roots and rhizosphere microorganisms. (Rhizosphere – Wikipedia)
2001: Van Bodegom et al. study methane oxidation and competition for oxygen in the rice rhizosphere. (Rhizosphere – Wikipedia)
2001: Hinsinger reviews the bioavailability of soil inorganic P in the rhizosphere. (Rhizosphere – Wikipedia)
2002: Chen et al. observe increased levels of microbial biomass and phosphatase extracellular enzymes in the rhizosphere. (Dijkstra et al., 2013)
2002: Sims et al. outline health effects of drought. (Parejko, 2024)
2003: Howell reviews mechanisms used by Trichoderma species in biological control. (Rhizosphere – Wikipedia)
2003: Ryu et al. show that bacterial volatiles promote growth in Arabidopsis. (Jamil et al., 2022)
2003: Bais et al. describe how plants communicate using the “underground information superhighway.” (Rhizosphere – Wikipedia; Jamil et al., 2022)
2003: Walker et al. discuss root exudation and rhizosphere biology. (Rhizosphere – Wikipedia)
2004: Pendall et al. observe rhizodeposition stimulated by elevated CO2 in a semiarid grassland. (Dijkstra et al., 2013)
2004: Bauer and Mathesius discuss plant responses to bacterial quorum sensing signals. (Jamil et al., 2022)
2005: Rasmussen et al. screen for quorum-sensing inhibitors. (Jamil et al., 2022)
2006: Bais et al. publish on the role of root exudates in rhizosphere interactions. (Plant root exudates – Wikipedia; Jamil et al., 2022)
2006: Oláh et al. show Nod factors and a diffusible factor from AMF stimulate lateral root formation. (Jamil et al., 2022)
2006: Stinson et al. find an invasive plant suppresses native tree seedlings by disrupting mutualisms. (Rhizosphere – Wikipedia)
2006: Watt et al. publish on rhizosphere biology and crop productivity. (How Does the Rhizosphere Effect Influence Plant Growth and Soil Health?)
2007: Carney et al. link altered soil microbial community at elevated CO2 to carbon loss. (Dijkstra et al., 2013)
2007: Liu et al. report that quorum-sensing signaling is required for antibiotic production in Serratia plymuthica. (Jamil et al., 2022)
2008: Barriuso et al. show transgenic tomato plants alter quorum sensing in PGPR. (Jamil et al., 2022)
2008: Dijkstra et al. report long-term enhancement of N availability and plant growth under elevated CO2 in a semi-arid grassland. (Dijkstra et al., 2013)
2008: Rudrappa et al. find malic acid recruits beneficial soil bacteria. (Jamil et al., 2022)
2008: Raynaud et al. model how plants alter competition by modifying nutrient bioavailability in the rhizosphere. (Rhizosphere – Wikipedia)
2009: Dijkstra et al. investigate if accelerated soil organic matter decomposition increases plant N availability. (Dijkstra et al., 2013)
2009: Taghavi et al. survey and characterize endophytic bacteria with beneficial effects on poplar trees. (Jamil et al., 2022)
2009: Crawford et al. highlight broad-ranging implications of climate change-induced droughts for global agriculture. (Parejko, 2024)
2009: Jones et al. discuss carbon flow in the rhizosphere. (Plant root exudates – Wikipedia; Dijkstra et al., 2013)
2009: Schoch et al. clarify the origin and evolution of fungal reproductive and ecological traits. (Applebaum et al., 2022)
2009: Yang et al. show rhizosphere bacteria help plants tolerate abiotic stress. (Jamil et al., 2022)
2009: Imran et al. study multiple traits of Ochrobactrum sp. Pv2Z2 including quorum sensing. (Jamil et al., 2022)
2010s: Advanced Research and Sustainable Agriculture
2010: Biedrzycki et al. demonstrate root exudates mediate kin recognition in plants. (Plant root exudates – Wikipedia)
2010: Jousset et al. show predator-prey chemical warfare determines gene expression in Pseudomonas fluorescens. (Rhizosphere – Wikipedia)
2010: Norby et al. find CO2 enhancement of forest productivity is constrained by limited nitrogen availability. (Dijkstra et al., 2013)
2010: Oldroyd et al. detail the roles of extracellular components in rhizobia-legume interactions. (Jamil et al., 2022)
2011: Maillet et al. identify fungal lipochitooligosaccharide symbiotic signals in arbuscular mycorrhiza. (Jamil et al., 2022)
2011: Phillips et al. report enhanced root exudation induces microbial feedbacks to N cycling under long-term CO2 fumigation. (Dijkstra et al., 2013)
2011: Teplitski et al. review perception and degradation of N-Acyl Homoserine Lactone quorum sensing signals by mammalian and plant cells. (Jamil et al., 2022)
2012: Wang et al. induce drought tolerance in cucumber plants with a PGPR consortium. (Jamil et al., 2022)
2013: Zolla et al. find soil microbiomes vary in ability to confer drought tolerance. (Jamil et al., 2022)
2013: Jansson and Taş review the microbial ecology of permafrost. (Rhizosphere – Wikipedia)
2013: Philippot et al. propose rhizosphere feedback where plants shape microbial communities. (Hakim et al., 2021)
2013: Rasmussen et al. suggest root exudates change microbial community colonizing plant roots under drought stress. (Parejko, 2024)
2014: Han et al. report systemic responses of barley to Acidovorax radicus N35. (Jamil et al., 2022)
2014: Kang et al. show Leifsonia soli stimulates growth of cucumber, radish, and tomato. (Hakim et al., 2021)
2014: Martínez-Hidalgo et al. report enhanced production in crops with bio-inoculants. (Hakim et al., 2021)
2014: Oldroyd reviews signaling systems that promote beneficial symbiotic associations in plants. (Jamil et al., 2022)
2015: Chowdhury et al. show cyclic lipopeptides from Bacillus amyloliquefaciens enhance plant defense responses. (Jamil et al., 2022)
2015: Kang et al. demonstrate Serratia nematodiphila mitigates low temperature effects on Capsicum annuum. (Hakim et al., 2021)
2015: Sasse et al. discuss how root exudates shape the root microbiome. (Jamil et al., 2022)
2016: Grosskinsky et al. show cytokinins produced by P. fluorescens control P. syringae infection. (Hakim et al., 2021)
2016: Kanchiswamy et al. discuss bioprospecting bacterial and fungal volatiles for sustainable agriculture. (Jamil et al., 2022)
2016: Mommer et al. propose a rhizosphere framework for root-root interactions. (Jamil et al., 2022)
2016: Okubo et al. study impacts of root symbiotic associations on sugar exudation rates. (Plant root exudates – Wikipedia)
2016: Rosier et al. offer a perspective on inter-kingdom signaling in plant–beneficial microbe interactions. (Jamil et al., 2022)
2017: Kang et al. show Leifsonia xyli maintains Solanum lycopersicum growth under copper stress. (Hakim et al., 2021)
2017: Kumar et al. report Rhizobium strain RL9 improved lentil nodulation and yield. (Hakim et al., 2021)
2018: Hu et al. find root exudate metabolites drive plant-soil feedbacks on growth and defense. (Plant root exudates – Wikipedia)
2018: Raheem et al. show auxin-producing PGPR improve wheat growth and yield under drought. (Hakim et al., 2021)
2018: Schmid et al. investigate bacterial diversity in offspring rhizospheres. (Hakim et al., 2021)
2018: Torres-Cortés et al. discuss biocontrol mechanisms of PGPR. (Hakim et al., 2021)
2019: Marchin et al. describe a simple method for simulating drought effects on plants. (Parejko, 2024)
2019: Wang et al. publish on phage combination therapies for bacterial wilt disease in tomato. (Jamil et al., 2022)
2019: Bolyen et al. introduce QIIME 2, a microbiome bioinformatics platform. (Parejko, 2024)
2019: Kang et al. report Bacillus tequilensis improved soybean biomass under high temperature stress. (Hakim et al., 2021)
2019: Canarini et al. discuss root exudation of primary metabolites. (Plant root exudates – Wikipedia)
2019: Qu et al. study rhizosphere microbiome assembly and its impact on plant growth. (Biology Notes Online)
2019: Egidi et al. find a few Ascomycota taxa dominate soil fungal communities worldwide. (Applebaum et al., 2022)
2020s: Current Research and Future Directions
2020: Jamil et al. (authors) describe rhizosphere signaling as a captivating environment and hotspot for microbial activity. (Jamil et al., 2022)
2020: Adedayo and Babalola discuss fungi that promote plant growth. (How Does the Rhizosphere Effect Influence Plant Growth and Soil Health?)
2020: Sharma et al. (authors) describe methods of total microbial DNA extraction. (Parejko, 2024)
2020: Parejko and others propose a course-embedded research project to study plant rhizosphere microbiomes under climate change, using Fast Plants. (Parejko, 2024)
2020: Oravec et al. demonstrate that root exudate metabolomes change under drought and show limited capacity for recovery. (Parejko, 2024)
2020: Zhang et al. (authors) identify a quorum quenching mechanism in Acinetobacter sp. strain XN-10. (Jamil et al., 2022)
2020: Olanrewaju et al. discuss the feedback effect of root exudates-rhizobiome interactions on plant health. (Jamil et al., 2022)
2020: Karma et al. describe the beneficial effects of root exudates changing the microbial community colonizing plant roots compared to normal conditions. (Parejko, 2024)
2021: Hakim et al. publish a review on Rhizosphere Engineering with Plant Growth-Promoting Microorganisms for Agriculture and Ecological Sustainability. (Hakim et al., 2021)
2021: Applebaum et al. publish a preliminary study on the structure and function of soil rhizosphere fungal communities in medicinal plants. (Applebaum et al., 2022)
2022: Jamil et al. publish a review on Rhizosphere Signaling: Insights into Plant–Rhizomicrobiome Interactions for Sustainable Agronomy. (Jamil et al., 2022)
2023: Ait-El-Mokhtar et al. provide insights into plant-microbiome interactions under drought. (Parejko, 2024)
2023: Benmrid et al. discuss bioinoculants for increasing crop tolerance to drought and phosphorus deficiency. (Parejko, 2024)
2023: Lv et al. describe the global magnitude of rhizosphere effects on soil microbial communities and carbon cycling. (How Does the Rhizosphere Effect Influence Plant Growth and Soil Health?)
2024 (March 18): Dr. Vijayalaxmi Kinhal publishes an article on “How Does the Rhizosphere Effect Influence Plant Growth and Soil Health?”. (How Does the Rhizosphere Effect Influence Plant Growth and Soil Health?)
2024 (June 18): James A. Parejko publishes “Climate change and plant rhizosphere microbiomes: an experiential course-embedded research project” in the Journal of Microbiology & Biology Education. (Parejko, 2024)
