Euphorbia milii-Endophytic Bacteria Interactions Affect Hormonal Levels of the Native Host Differently Under Various Airborne Pollutants

This study was conducted to assess the effect of plant–native endophytic bacteria interactions on indole-3-acetic acid (IAA), ethylene levels, and hormonal balance of Euphorbia milii under different airborne pollutants. IAA levels and airborne formaldehyde removal by E. milii enhanced when inoculated with endophytic isolates. However, one isolate, designated as root endophyte 4, with the highest levels of IAA production individually, declined gaseous formaldehyde removal of plant, since it disturbed hormonal balance of E. milii, leading to IAA levels higher than physiological concentrations, which stimulated ethylene biosynthesis and stomatal closure under light conditions. However, plant–root endophyte 4 interactions favored airborne benzene removal, since benzene was more phytotoxic and the plant needed more IAA to protect against benzene phytotoxicity. As trimethylamine (TMA) was not toxic, it did not affect plant-endophyte interactions. Therefore, IAA levels of root endophyte 4–inoculated E. milii was not significantly different from a noninoculated one. Under mixed-pollutant stress (formaldehyde, benzene, TMA), root endophyte 4–inoculated E. milii removed benzene at the lowest rate, since benzene was the most phytotoxic pollutant with the greatest molecular mass. However, TMA (with greater molecular mass) was removed faster than formaldehyde due to higher phytotoxicity of formaldehyde. Plant-endophyte interactions were affected differently under various airborne pollutants.

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Mistletoe ecophysiology: host–parasite interactionsThis review is one of a collection of papers based on a presentation from the Stem and Shoot Fungal Pathogens and Parasitic Plants: the Values of Biological Diversity session of the XXII International Union of Forestry Research Organization World Congress meeting held in Brisbane, Queensland, Australia, in 2005.

Botany ◽

10.1139/b08-096 ◽

2009 ◽

Vol 87 (1) ◽

pp. 10-15 ◽

Cited By ~ 60

Author(s):

G. Glatzel ◽

B. W. Geils

Keyword(s):

Water Potential ◽

Fungal Pathogens ◽

Biological Diversity ◽

Plant Root ◽

Stomatal Closure ◽

Xylem Water Potential ◽

Active Uptake ◽

Host Interaction ◽

High Concentrations ◽

Plant Root System

Mistletoes are highly specialized perennial flowering plants adapted to parasitic life on aerial parts of their hosts. In our discussion on the physiological interactions between parasite and host, we focus on water relations, mineral nutrition, and the effect of host vigour. When host photosynthesis is greatest, the xylem water potential of the host is most negative. To maintain a flux gradient and avoid stomatal closure and wilting, the mistletoe must tolerate a more negative water potential than the host. Succulent leaves enhance water storage and allow mistletoes to rehydrate before their hosts rehydrate. Mistletoe infections may disrupt the host stomatal control system, causing early and oscillating closure of host stomata, thereby diminishing host photosynthetic gain. Mistletoes lack the active uptake of minerals of a typical plant root system and rely upon the haustorium to connect with the host for the essentially one-way flow of photosynthates and nutrients from host to parasite. Modest growth rates, tolerance, succulence, and rapid leaf turnover are some means by which mistletoes avoid mineral deficiency or excess. We propose high concentrations of some mobile elements in the mistletoe by comparison with the host result not from active uptake, but from the inevitable accumulation by a parasite that utilizes host phloem sap. The relationship between host condition and mistletoe performance varies by situation and over time. In some cases, the host can outgrow the mistletoe, but favorable host status can also accelerate mistletoe growth. A better understanding of the mistletoe–host interaction can be utilized in improved management of infested forest plantations for resource production as well as for conservation of biodiversity and endangered species.

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Girdling changes root and shoot hormonal balance but does not alter drought-induced stomatal closure in soybean

Environmental and Experimental Botany ◽

10.1016/j.envexpbot.2021.104657 ◽

2021 ◽

Vol 192 ◽

pp. 104657

Author(s):

Pedro Castro-Valdecantos ◽

Jaime Puértolas ◽

Alfonso Albacete ◽

Ian C. Dodd

Keyword(s):

Stomatal Closure ◽

Hormonal Balance

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EFEKTIFITAS BAKTERI ENDOFIT DAN PENAMBAHAN INDOLE ACETIC ACID (IAA) DALAM MENINGKATKAN PERTUMBUHAN TANAMAN PADI Oryza sativa L.

Scripta Biologica ◽

10.20884/1.sb.2017.4.3.542 ◽

2017 ◽

Vol 4 (3) ◽

pp. 177

Author(s):

Aria Rizki Ramadhan ◽

Oedjijono Oedjijono ◽

Ratih Dewi Hastuti

Keyword(s):

Plant Growth ◽

Endophytic Bacteria ◽

Rice Plant ◽

Plant Root ◽

Rice Variety ◽

Combined Treatment ◽

Soil Biology ◽

Randomized Design ◽

Two Factors ◽

Different Doses

Rice plant needs essential and non-essential nutrients to grow. However, the use of inorganic fertilizers may affect the soil microbe community which expected to increase the availability of nutrients for both plants and microbes, a condition that could control several types of diseases. Many efforts were made to find alternative fertilizer which environmentally friendly, for instance by exploiting microorganisms such as endophytic bacteria associated with plant tissue or seed plant cell. This research aimed to determine the effect of endophytic bacteria, the concentration of IAA, and the combination of endophytic bacteria with a concentration of IAA, on the growth of rice plant. This research was conducted at the Laboratory of Soil Biology, The Soil Research Institute located in Cimanggu Bogor from December 2015 to February 2016. This research was a Completely Randomized Design (CRD) with two factors, i.e., the inoculant of endophytic bacteria (2.2 KT, KR 6, and I CM), and the concentration of IAA (0, 0.01, 0.1, 0.5, and 1 ppm). Three replicates were applied for each treatment of the inoculant combined with different doses of IAA. The variety of rice plants tested were Inpari 13 and IR 64. The potential test has been applied to determine the factor with the highest yield of the rice plant growth. The parameters observed were the height of the rice plant, the length of the rice plant roots, and the total weight of the plant including root. The results showed the inocula of endophytic bacteria alone had no effect to increase growth for both IR 64 and Inpari 13 rice variety. The IAA concentration of 0.1 ppm was able to increase the height of rice plant and the length of rice plant root for both IR 64 rice plant and Inpari 13. The combined treatment of KR 6 bacterial inoculum with 1 ppm of IAA concentration was effectively promoted rice plant growth for both IR 64 and Inpari 13.

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Enrichment of Root Endophytic Bacteria from Populus deltoides and Single-Cell-Genomics Analysis

Applied and Environmental Microbiology ◽

10.1128/aem.01285-16 ◽

2016 ◽

Vol 82 (18) ◽

pp. 5698-5708 ◽

Cited By ~ 31

Author(s):

Sagar M. Utturkar ◽

W. Nathan Cude ◽

Michael S. Robeson ◽

Zamin K. Yang ◽

Dawn M. Klingeman ◽

...

Keyword(s):

Single Cell ◽

Endophytic Bacteria ◽

Plant Material ◽

Plant Biomass ◽

Plant Root ◽

Gradient Centrifugation ◽

Substantial Reduction ◽

Comparative Genomic ◽

Single Cell Genomics ◽

Content Type

ABSTRACTBacterial endophytes that colonizePopulustrees contribute to nutrient acquisition, prime immunity responses, and directly or indirectly increase both above- and below-ground biomasses. Endophytes are embedded within plant material, so physical separation and isolation are difficult tasks. Application of culture-independent methods, such as metagenome or bacterial transcriptome sequencing, has been limited due to the predominance of DNA from the plant biomass. Here, we describe a modified differential and density gradient centrifugation-based protocol for the separation of endophytic bacteria fromPopulusroots. This protocol achieved substantial reduction in contaminating plant DNA, allowed enrichment of endophytic bacteria away from the plant material, and enabled single-cell genomics analysis. Four single-cell genomes were selected for whole-genome amplification based on their rarity in the microbiome (potentially uncultured taxa) as well as their inferred abilities to form associations with plants. Bioinformatics analyses, including assembly, contamination removal, and completeness estimation, were performed to obtain single-amplified genomes (SAGs) of organisms from the phylaArmatimonadetes,Verrucomicrobia, andPlanctomycetes, which were unrepresented in our previous cultivation efforts. Comparative genomic analysis revealed unique characteristics of each SAG that could facilitate future cultivation efforts for these bacteria.IMPORTANCEPlant roots harbor a diverse collection of microbes that live within host tissues. To gain a comprehensive understanding of microbial adaptations to this endophytic lifestyle from strains that cannot be cultivated, it is necessary to separate bacterial cells from the predominance of plant tissue. This study provides a valuable approach for the separation and isolation of endophytic bacteria from plant root tissue. Isolated live bacteria provide material for microbiome sequencing, single-cell genomics, and analyses of genomes of uncultured bacteria to provide genomics information that will facilitate future cultivation attempts.

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Effect of methyl jasmonate on ethylene biosynthesis and stomatal closure in olive leaves

Phytochemistry ◽

10.1016/0031-9422(93)85504-k ◽

1993 ◽

Vol 33 (2) ◽

pp. 285-289 ◽

Cited By ~ 19

Author(s):

Luis C. Sanz ◽

Juan C. Fernández-Maculet ◽

Eduardo Gómez ◽

Blanca Vioque ◽

Jose M. Olías

Keyword(s):

Methyl Jasmonate ◽

Stomatal Closure ◽

Ethylene Biosynthesis ◽

Olive Leaves

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The Endophytic Microbiome as a Hotspot of Synergistic Interactions, with Prospects of Plant Growth Promotion

Biology ◽

10.3390/biology10020101 ◽

2021 ◽

Vol 10 (2) ◽

pp. 101

Author(s):

Udaya Kumar Vandana ◽

Jina Rajkumari ◽

L. Paikhomba Singha ◽

Lakkakula Satish ◽

Hemasundar Alavilli ◽

...

Keyword(s):

Plant Growth ◽

Microbial Communities ◽

Plant Growth Promotion ◽

Endophytic Bacteria ◽

Host Plants ◽

Plant Pathogens ◽

Growth Promotion ◽

Plant Root ◽

Endophytic Microorganisms ◽

Microbe Interactions

The plant root is the primary site of interaction between plants and associated microorganisms and constitutes the main components of plant microbiomes that impact crop production. The endophytic bacteria in the root zone have an important role in plant growth promotion. Diverse microbial communities inhabit plant root tissues, and they directly or indirectly promote plant growth by inhibiting the growth of plant pathogens, producing various secondary metabolites. Mechanisms of plant growth promotion and response of root endophytic microorganisms for their survival and colonization in the host plants are the result of complex plant-microbe interactions. Endophytic microorganisms also assist the host to sustain different biotic and abiotic stresses. Better insights are emerging for the endophyte, such as host plant interactions due to advancements in ‘omic’ technologies, which facilitate the exploration of genes that are responsible for plant tissue colonization. Consequently, this is informative to envisage putative functions and metabolic processes crucial for endophytic adaptations. Detection of cell signaling molecules between host plants and identification of compounds synthesized by root endophytes are effective means for their utilization in the agriculture sector as biofertilizers. In addition, it is interesting that the endophytic microorganism colonization impacts the relative abundance of indigenous microbial communities and suppresses the deleterious microorganisms in plant tissues. Natural products released by endophytes act as biocontrol agents and inhibit pathogen growth. The symbiosis of endophytic bacteria and arbuscular mycorrhizal fungi (AMF) affects plant symbiotic signaling pathways and root colonization patterns and phytohormone synthesis. In this review, the potential of the root endophytic community, colonization, and role in the improvement of plant growth has been explained in the light of intricate plant-microbe interactions.

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The fungal root endophyte Serendipita vermifera displays inter-kingdom synergistic beneficial effects with the microbiota in Arabidopsis thaliana and barley

10.1101/2021.03.18.435831 ◽

2021 ◽

Author(s):

Lisa K. Mahdi ◽

Shingo Miyauchi ◽

Charles Uhlmann ◽

Ruben Garrido-Oter ◽

Gregor Langen ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Growth Promotion ◽

Plant Root ◽

List Type ◽

Microbiota Composition ◽

Pathogen Infection ◽

Associated Bacteria ◽

Root Endophyte ◽

Beneficial Effects ◽

Bacterial Microbiota

AbstractPlant root-associated bacteria can confer protection against pathogen infection. By contrast, the beneficial effects of root endophytic fungi and their synergistic interactions with bacteria remain poorly defined. We demonstrate that the combined action of a fungal root endophyte from a widespread taxon with core bacterial microbiota members provides synergistic protection against an aggressive soil-borne pathogen in Arabidopsis thaliana and barley. We additionally show early inter-kingdom growth promotion benefits which are host and microbiota composition dependent.HighlightsThe root endophytic fungus Serendipita vermifera can functionally replace core bacterial microbiota members in mitigating pathogen infection and disease symptoms.S. vermifera additionally stabilizes and potentiates the protective activities of root-associated bacteria and mitigates the negative effects of a non-native bacterial community in A. thaliana.Inter-kingdom synergistic beneficial effects do not require extensive host transcriptional reprogramming nor high levels of S. vermifera colonisation.Inter-kingdom protective benefits are largely independent of the host while synergism leading to early inter-kingdom growth promotion is driven by host species and microbiota composition.

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