Epiphyte-cover on seagrass (Zostera marina L.) leaves impedes plant performance and radial O2 loss from the below-ground tissue

Abstract. The dynamics of the physicochemical and biological parameters were followed during the decline of a Cymodocea nodosa meadow in the northern Adriatic Sea from July 2017 to October 2018. During the regular growth of C. nodosa from July 2017 to March 2018, C. nodosa successfully adapted to the changes of environmental conditions and prevented H2S accumulation by its re-oxidation, supplying the sediment with O2 from the water column and/or leaf photosynthesis. The C. nodosa decline was most likely triggered in April 2018 by a reduction of light availability which affected photosynthesis of C. nodosa and the oxidation capability of below-ground tissue. Simultaneously, a depletion of oxygen due to intense oxidation of H2S occurred in the sediment, thus creating anoxic conditions in most of the rooted areas. These linked negative effects on the plant performance caused an accumulation of H2S in the sediments of the C. nodosa meadow. During the decay of above- and below-ground tissues, culminating in August 2018, high concentrations of H2S were reached and accumulated in the sediment as well as in bottom waters. The influx of oxygenated waters in September 2018 led to the re-establishment of H2S oxidation and recovery of the below-ground tissue. Our results indicate that if disturbance of environmental conditions, particularly those compromising the light availability, take place during the recruitment phase of plant growth when metabolic needs are at maximum and stored reserves minimal, a sudden and drastic decline of the seagrass meadow occurs.

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The response of western juniper (Juniperusoccidentalis) to reductions in above-and below-ground tissue

Canadian Journal of Forest Research ◽

10.1139/x91-025 ◽

1991 ◽

Vol 21 (2) ◽

pp. 207-216 ◽

Cited By ~ 5

Author(s):

P. M. Miller ◽

L. E. Eddleman ◽

J. M. Miller

Keyword(s):

Carbon Dioxide ◽

Water Use ◽

Lateral Roots ◽

Nitrogen Concentration ◽

Carbon Dioxide Assimilation ◽

Ground Tissue ◽

Photosynthetic Nitrogen Use Efficiency ◽

Nitrogen Use ◽

Below Ground ◽

Use Efficiency

Plants are balanced systems that integrate processes of carbon fixation and uptake of water and nutrients to optimize resource acquisition. Response of Juniperusoccidentalis Hook. to reductions in above- and below-ground tissue was measured to determine effects on carbon dioxide assimilation, leaf conductance, intercellular carbon dioxide, xylem water potential, foliage nutrient concentration, aboveground growth, water-use efficiency, and potential photosynthetic nitrogen-use efficiencies. Approximately 50% of the old foliage was removed and lateral roots were severed at the canopy edge in early April 1988; physiological processes were measured during three periods in the summer of 1988. Foliage removal increased rates of carbon dioxide assimilation and photosynthetic nitrogen-use efficiency, but neither increased growth nor improved water status or nitrogen concentration of remaining foliage. Cutting lateral roots reduced assimilation, leaf conductance, foliage nitrogen concentration, branchlet elongation, water-use efficiency, and photosynthetic nitrogen-use efficiency. By late August, juvenile and small-adult J. occidentalis in the cut-top treatment had compensated for foliage removal by reestablishing patterns of water-use efficiencies similar to those of control plants, which may indicate that an overall metabolic control was functioning to regulate the balance between carbon dioxide assimilation and water loss. Cutting lateral roots had a more lasting effect on efficiencies; by late August, juveniles and small adults still had significantly lower water-use efficiencies than controls.

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Uprooting of Zostera marina Shoots in Relation to Below-ground Biomass Reduction under Low Light and High Sulfide Conditions

Journal of Water and Environment Technology ◽

10.2965/jwet.2011.235 ◽

2011 ◽

Vol 9 (3) ◽

pp. 235-247

Author(s):

Hitoshi TAMAKI ◽

Atsushi FUKAYA ◽

Daisuke MURAOKA

Keyword(s):

Zostera Marina ◽

Low Light ◽

Ground Biomass ◽

Below Ground ◽

Biomass Reduction ◽

High Sulfide

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Root-to-shoot signalling: integration of diverse molecules, pathways and functions

Functional Plant Biology ◽

10.1071/fp15252 ◽

2016 ◽

Vol 43 (2) ◽

pp. 87 ◽

Cited By ~ 56

Author(s):

Sergey Shabala ◽

Rosemary G. White ◽

Michael A. Djordjevic ◽

Yong-Ling Ruan ◽

Ulrike Mathesius

Keyword(s):

Current Knowledge ◽

Dynamic Environment ◽

Plant Performance ◽

Plant Roots ◽

Specific Information ◽

Plant Parts ◽

Efficient Communication ◽

Communication Modes ◽

Below Ground ◽

Signalling Systems

Plant adaptive potential is critically dependent upon efficient communication and co-ordination of resource allocation and signalling between above- and below-ground plant parts. Plant roots act as gatekeepers that sense and encode information about soil physical, chemical and biological factors, converting them into a sophisticated network of signals propagated both within the root itself, and also between the root and shoot, to optimise plant performance for a specific set of conditions. In return, plant roots receive and decode reciprocal information coming from the shoot. The communication modes are highly diverse and include a broad range of physical (electric and hydraulic signals, propagating Ca2+ and ROS waves), chemical (assimilates, hormones, peptides and nutrients), and molecular (proteins and RNA) signals. Further, different signalling systems operate at very different timescales. It remains unclear whether some of these signalling systems operate in a priming mode(s), whereas others deliver more specific information about the nature of the signal, or whether they carry the same ‘weight’. This review summarises the current knowledge of the above signalling mechanisms, and reveals their hierarchy, and highlights the importance of integration of these signalling components, to enable optimal plant functioning in a dynamic environment.

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Root herbivory indirectly affects above- and below-ground community members and directly reduces plant performance

Journal of Ecology ◽

10.1111/1365-2745.12464 ◽

2015 ◽

Vol 103 (6) ◽

pp. 1509-1518 ◽

Cited By ~ 18

Author(s):

Nicholas A. Barber ◽

Nelson J. Milano ◽

E. Toby Kiers ◽

Nina Theis ◽

Vanessa Bartolo ◽

...

Keyword(s):

Plant Performance ◽

Community Members ◽

Root Herbivory ◽

Below Ground

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Of mutualism and migration: will interactions with novel ericoid mycorrhizal communities help or hinder northward Rhododendron range shifts?

Oecologia ◽

10.1007/s00442-021-05081-9 ◽

2022 ◽

Author(s):

Taryn L. Mueller ◽

Elena Karlsen-Ayala ◽

David A. Moeller ◽

Jesse Bellemare

Keyword(s):

Mycorrhizal Fungi ◽

Critical Role ◽

Biotic Interactions ◽

Leaf Size ◽

Plant Performance ◽

Native Range ◽

Reciprocal Effect ◽

Below Ground ◽

And Migration ◽

Assisted Colonization

AbstractRapid climate change imperils many small-ranged endemic species as the climate envelopes of their native ranges shift poleward. In addition to abiotic changes, biotic interactions are expected to play a critical role in plant species’ responses. Below-ground interactions are of particular interest given increasing evidence of microbial effects on plant performance and the prevalence of mycorrhizal mutualisms. We used greenhouse mesocosm experiments to investigate how natural northward migration/assisted colonization of Rhododendron catawbiense, a small-ranged endemic eastern U.S. shrub, might be influenced by novel below-ground biotic interactions from soils north of its native range, particularly with ericoid mycorrhizal fungi (ERM). We compared germination, leaf size, survival, and ERM colonization rates of endemic R. catawbiense and widespread R. maximum when sown on different soil inoculum treatments: a sterilized control; a non-ERM biotic control; ERM communities from northern R. maximum populations; and ERM communities collected from the native range of R. catawbiense. Germination rates for both species when inoculated with congeners' novel soils were significantly higher than when inoculated with conspecific soils, or non-mycorrhizal controls. Mortality rates were unaffected by treatment, suggesting that the unexpected reciprocal effect of each species’ increased establishment in association with heterospecific ERM could have lasting demographic effects. Our results suggest that seedling establishment of R. catawbiense in northern regions outside its native range could be facilitated by the presence of extant congeners like R. maximum and their associated soil microbiota. These findings have direct relevance to the potential for successful poleward migration or future assisted colonization efforts.

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Foliar resistance to Rhizoctonia solani in Arabidopsis is compromised by simultaneous loss of ethylene, jasmonate and PEN2 mediated defense pathways

Scientific Reports ◽

10.1038/s41598-021-81858-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Brendan N. Kidd ◽

Rhonda Foley ◽

Karam B. Singh ◽

Jonathan P. Anderson

Keyword(s):

Rhizoctonia Solani ◽

Reference Strain ◽

Anastomosis Group ◽

Broad Host Range ◽

Ground Tissue ◽

Redox Sensor ◽

Significant Difference ◽

Foliar Resistance ◽

Below Ground ◽

Simultaneous Loss

AbstractRhizoctonia solani causes damaging yield losses on most major food crops. R. solani isolates belonging to anastomosis group 8 (AG8) are soil-borne, root-infecting pathogens with a broad host range. AG8 isolates can cause disease on wheat, canola and legumes, however Arabidopsis thaliana is heretofore thought to possess non-host resistance as A. thaliana ecotypes, including the reference strain Col-0, are resistant to AG8 infection. Using a mitochondria-targeted redox sensor (mt-roGFP2) and cell death staining, we demonstrate that both AG8 and a host isolate (AG2-1) of R. solani are able to infect A. thaliana roots. Above ground tissue of A. thaliana was found to be resistant to AG8 but not AG2. Genetic analysis revealed that ethylene, jasmonate and PENETRATION2-mediated defense pathways work together to provide resistance to AG8 in the leaves which subsequently enable tolerance of root infections. Overall, we demonstrate a significant difference in defense capabilities of above and below ground tissue in providing resistance to R. solani AG8 in Arabidopsis.

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Spatial regulation of thermomorphogenesis by HY5 and PIF4 in Arabidopsis

Nature Communications ◽

10.1038/s41467-021-24018-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Sanghwa Lee ◽

Wenli Wang ◽

Enamul Huq

Keyword(s):

Ambient Temperature ◽

Morphological Changes ◽

High Ambient Temperature ◽

Tissue Response ◽

Ground Tissue ◽

Tissue Specific ◽

Spatial Regulation ◽

Specific Manner ◽

Below Ground ◽

The Stability

AbstractPlants respond to high ambient temperature by implementing a suite of morphological changes collectively termed thermomorphogenesis. Here we show that the above and below ground tissue-response to high ambient temperature are mediated by distinct transcription factors. While the central hub transcription factor, PHYTOCHROME INTERCTING FACTOR 4 (PIF4) regulates the above ground tissue response, the below ground root elongation is primarily regulated by ELONGATED HYPOCOTYL 5 (HY5). Plants respond to high temperature by largely expressing distinct sets of genes in a tissue-specific manner. HY5 promotes root thermomorphogenesis via directly controlling the expression of many genes including the auxin and BR pathway genes. Strikingly, the above and below ground thermomorphogenesis is impaired in spaQ. Because SPA1 directly phosphorylates PIF4 and HY5, SPAs might control the stability of PIF4 and HY5 to regulate thermomorphogenesis in both tissues. These data collectively suggest that plants employ distinct combination of SPA-PIF4-HY5 module to regulate tissue-specific thermomorphogenesis.

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Seasonal Changes in Nonstructural Carbohydrates in Cranberry

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.119.5.1029 ◽

1994 ◽

Vol 119 (5) ◽

pp. 1029-1033 ◽

Cited By ~ 21

Author(s):

Marianna Hagidimitriou ◽

Teryl R. Roper

Keyword(s):

Seasonal Changes ◽

Fruit Set ◽

Fruit Weight ◽

Soluble Carbohydrates ◽

Nonstructural Carbohydrates ◽

Ground Tissue ◽

Carbohydrate Concentration ◽

Nonstructural Carbohydrate ◽

Subsequent Decrease ◽

Below Ground

`Searles' (low yielding) and `Stevens' (high yielding) cranberry (Vaccinium macrocarpon Ait.) tissues were collected in 1990 and 1991 to determine the concentration of nonstructural carbohydrates in above-ground (uprights, woody stems) and below-ground tissue. Uprights had the highest total nonstructural carbohydrate (TNC) concentration, followed by woody stems, while below-ground tissue contained the lowest TNC concentration. Total nonstructural carbohydrate concentration in uprights increased early in the season, reached a maximum in late May, decreased as flowering approached, and remained low from late June to late August. The latter period corresponds to flowering, fruit set, floral initiation, and fruit development stages. In late August, when fruit were full size, TNC levels increased, reaching highest concentration in November as the plants were entering dormancy. Most TNC increase in the early season and the subsequent decrease were due to changes in starch. The increase of TNC late in the season was primarily due to increases in soluble carbohydrates. Total nonstructural carbohydrate concentration was greater in vegetative than fruiting uprights for the entire growing season. The lower TNC concentration in fruiting than vegetative uprights during flowering and fruit set was due to greater starch depletion in fruiting uprights. Seasonal changes in TNC in the two cultivars were similar; however, `Stevens' had generally higher TNC concentration and total dry weight as well as more fruiting uprights, fruit, and fruit weight per ground area. The low TNC concentration observed during fruit set and development suggests that the demands for carbohydrates are highest during that period and supports the hypothesis that competition for carbohydrate resources is one factor responsible for low cranberry fruit set.

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Drought Stress alters Solute Allocation in Broadleaf Dock (Rumex obtusifolius)

Weed Science ◽

10.1614/ws-d-12-00074.1 ◽

2013 ◽

Vol 61 (1) ◽

pp. 104-108 ◽

Cited By ~ 8

Author(s):

Anna Katarina Gilgen ◽

Urs Feller

Keyword(s):

Resource Allocation ◽

Drought Stress ◽

Central Europe ◽

Climate Models ◽

Plant Performance ◽

Rumex Obtusifolius ◽

Plant Parts ◽

Short Period ◽

Below Ground ◽

Source Sink

According to climate models, drier summers must be expected more frequently in Central Europe during the next decades, which may influence plant performance and competition in grassland. The overall source–sink relations in plants, especially allocation of solutes to above- and below-ground parts, may be affected by drought. To investigate solute export from a given leaf of broadleaf dock, a solution containing57Co and65Zn was introduced through a leaf flap. The export from this leaf was detected by analysing radionuclide contents in various plant parts. Less label was allocated to new leaves and more to roots under drought. The observed alterations of source–sink relations in broadleaf dock were reversible during a subsequent short period of rewatering. These findings suggest an increased resource allocation to roots under drought improving the functionality of the plants.

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