EMBOLISM INCREASE AND ANATOMICAL MODIFICATIONS CAUSED BY A PARASITIC PLANT: PHORADENDRON CRASSIFOLIUM (SANTALACEAE) ON TAPIRIRA GUIANENSIS (ANACARDIACEAE)

Parasitic plants are capable of causing a variety of effects to their hosts, including alterations in the process of wood formation. However, the majority of studies dealing with parasitic plant anatomy have focused on the host–parasite interface and the direct action of the haustorium, which is the organ responsible for attaching the parasite to the host. Considering this gap, we studied the anatomical and functional effects caused by a mistletoe species, Phoradendron crassifolium (Santalaceae), on the wood anatomy of the host tree Tapirira guianensis (Anacardiaceae). Both parasitized and non-parasitized branches were collected from host trees. Traditional wood anatomy procedures were employed, along with functionality experiments using the ascent of safranin solution through the xylem. Prior to the analysis, all sampled branches were divided in “upstream” and “downstream” portions, considering the direction of xylem sap flow inside the plant body. This design was chosen in order to avoid biased results derived from normal ontogeny-related wood anatomical and functional changes. Our results showed that infested wood expressed a higher density of embolized vessels, narrower vessel lumen diameter, higher vessel density, taller and wider rays, and fibers with thinner cell walls. All these responses were most conspicuous in the downstream sections of the parasitized branches. We propose that the wood anatomical and functional alterations were induced by the combination of water stress caused by water use by the parasite and consequent low turgor in differentiating cambial derivates; by unbalanced auxin/cytokinin concentrations originating at the infestation region due to phloem disruptions caused by the parasite’s penetration and action; and by higher than usual ethylene levels. Further analysis of hydraulic conductivity and hormonal changes in host branches are necessary to test this hypothesis.

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Comparative Study of the Antibacterial Potential of Phragmanthera Capitata (Sprengel) S. Balle (Loranthaceae) Extracts, a Parasitic Plant Collected From Three Host Trees

Haya The Saudi Journal of Life Sciences ◽

10.36348/sjls.2021.v06i02.001 ◽

2021 ◽

Vol 6 (2) ◽

pp. 19-27

Author(s):

Ladoh-Yemeda Christelle Flora ◽

Ngoule Charles Christian ◽

Ngene Jean Pierre ◽

Ndjip Rosette Christelle ◽

Nyegue Maximillienne Ascension ◽

...

Keyword(s):

Comparative Study ◽

Parasitic Plant ◽

Host Trees ◽

Antibacterial Potential

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PECULIARITIES OF PATHOMORPHOLOGICAL DIAGNOSIS OF THE MOST COMMON RESPIRATORY INFECTIONS OF A PIG

Integration of traditional and innovative scientific researches: global trends and regional aspect ◽

10.30525/978-9934-26-001-8-3-13 ◽

2020 ◽

Author(s):

Oleksiy Tkachenko ◽

◽

Olena Havrylina ◽

Keyword(s):

Lymph Nodes ◽

Inflammatory Process ◽

Mononuclear Cells ◽

Respiratory Infections ◽

Morphological Changes ◽

Direct Action ◽

Immunohistochemical Analysis ◽

Regional Lymph Nodes ◽

Functional Changes ◽

Progressive Development

The active spread of respiratory infections in pig farms raises the issue of differential pathomorphological diagnosis of diseases related to a single syndrome of respiratory pathologies. Pathological autopsy and histopathological examinations of organs from 72 carcasses of pigs during the fattening period were performed. Pathological autopsy of pigs was performed by complete evisceration. Histologically examined 360 lung samples with regional lymph nodes. The presence of bacterial and viral infections was confirmed by bacteriological and PCR studies. The aim of the study is to establish the characteristic differential features at the macro- and micro-level in the lungs of domestic pigs for viral and bacterial pathogens. The main tasks of the work are to determine the morphofunctional features and dynamics of pathomorphological changes in the parenchyma and immune formations of the lungs in respiratory pathology. As a result of complex pathomorphological studies of the lungs in respiratory infections of pigs found that structural and functional changes in the body have different localization, stage and nature of the pathological process, which depend on the direct action of the etiological factor. Acute catarrhal bronchopneumonia is registered in respiratory mycoplasmosis (enzootic pneumonia), which in a prolonged course turns into chronic catarrhal or catarrhal-purulent pneumonia. Hemorrhagic necrotizing pneumonia is a manifestation of actinobacillary pleuropneumonia. Interstitial (diffuse proliferative) pneumonia develops with viral pathogens - circovirus infection and reproductive and respiratory syndrome of pigs (PRRS). Serous fibrinous and fibrinous pleurisy develop in hemophilic polyserositis and actinobacillary pleuropneumonia. Pathomorphological changes of the lungs in the reproductive and respiratory syndrome of pigs are polymorphic and are manifested by the gradual progressive development of the inflammatory process from congestive hyperemia, acute catarrh to diffuse interstitial pneumonia. Pathomorphological changes of the lungs in mycoplasmosis (enzootic pleuropneumonia) of pigs are polymorphic and are manifested by the gradual progressive development of the inflammatory process, which is localized in the cranial, middle and peripheral parts of the diaphragmatic particles and is characterized by acute catarrhal bronchopneumonia. In actinobacillary pleuropneumonia pathohistological studies revealed a pronounced stage of morphological changes in the lungs and regional lymph nodes in actinobacillary pleuropneumonia. Depending on the form of the disease, serous-hemorrhagic exudation is exacerbated by fibrinogen exudation and increased migration of lymphocytes and mononuclear cells. In subacute and chronic forms of the disease, necrotic phenomena prevail in combination with areas of serous-fibrinous inflammation. In the future, further studies of immunohistochemical analysis to establish the tropism of the pathogen and the study of markers of lymphoid cells.

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Microscale Xylem Sap Flow Sensor Facilitating the Simultaneous Measurement of Flow Velocity and Direction

Proceedings ◽

10.3390/proceedings2130824 ◽

2019 ◽

Vol 2 (13) ◽

pp. 824

Author(s):

Yuki Hara ◽

Naoki Hara ◽

Hiroki Ishizuka ◽

Kyohei Terao ◽

Hidekuni Takao ◽

...

Keyword(s):

Flow Velocity ◽

Simultaneous Measurement ◽

Sap Flow ◽

Xylem Sap ◽

Flow Sensor ◽

Functional Verification ◽

Thermal Flow Sensor ◽

Quantitative Monitoring ◽

Mems Technology ◽

Xylem Sap Flow

In this study, we focused on direct and quantitative monitoring of sap dynamics in plant stems, and proposed the microscale xylem sap flow sensor. This sensor facilitates the simultaneous measurement of flow velocity and direction by combining the principles of a Granier sensor and a thermal flow sensor. We fabricated micro-sensor chips for functional verification by using MEMS technology, and assembled them on a resin film to facilitate mounting on the epidermis of plants. Furthermore, we measured the sap dynamics by using an experimental setup, and succeeded in measuring the flow velocity and direction at the same time.

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In vivo pressure gradient heterogeneity increases flow contribution of small diameter vessels in grapevine

Nature Communications ◽

10.1038/s41467-019-13673-6 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 8

Author(s):

Martin Bouda ◽

Carel W. Windt ◽

Andrew J. McElrone ◽

Craig R. Brodersen

Keyword(s):

Sap Flow ◽

Xylem Sap ◽

Small Diameter ◽

Fourth Power ◽

First Year ◽

Long Distance ◽

Xylem Sap Flow ◽

Flow Mri ◽

Vessel Network

AbstractLeaves lose approximately 400 H2O molecules for every 1 CO2 gained during photosynthesis. Most long-distance water transport in plants, or xylem sap flow, serves to replace this water to prevent desiccation. Theory predicts that the largest vessels contribute disproportionately to overall sap flow because flow in pipe-like systems scales with the fourth power of radius. Here, we confront these theoretical flow predictions for a vessel network reconstructed from X-ray μCT imagery with in vivo flow MRI observations from the same sample of a first-year grapevine stem. Theoretical flow rate predictions based on vessel diameters are not supported. The heterogeneity of the vessel network gives rise to transverse pressure gradients that redirect flow from wide to narrow vessels, reducing the contribution of wide vessels to sap flow by 15% of the total. Our results call for an update of the current working model of the xylem to account for its heterogeneity.

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