The relative abundance of viable spores of Gibberella zeae in the planetary boundary layer suggests the role of long-distance transport in regional epidemics of Fusarium head blight

Long-distance transport is crucial for polar-growing cells, such as neurons and fungal hyphae. Kinesins and myosins participate in this process, but their functional interplay is poorly understood. Here, we investigate the role of kinesin motors in hyphal growth of the plant pathogen Ustilago maydis. Although the microtubule plus-ends are directed to the hyphal tip, of all 10 kinesins analyzed, only conventional kinesin (Kinesin-1) and Unc104/Kif1A-like kinesin (Kinesin-3) were up-regulated in hyphae and they are essential for extended hyphal growth. Δkin1 and Δkin3 mutant hyphae grew irregular and remained short, but they were still able to grow polarized. No additional phenotype was detected in Δkin1rkin3 double mutants, but polarity was lost in Δmyo5rkin1 and Δmyo5rkin3 mutant cells, suggesting that kinesins and class V myosin cooperate in hyphal growth. Consistent with such a role in secretion, fusion proteins of green fluorescent protein and Kinesin-1, Myosin-V, and Kinesin-3 accumulate in the apex of hyphae, a region where secretory vesicles cluster to form the fungal Spitzenkörper. Quantitative assays revealed a role of Kin3 in secretion of acid phosphatase, whereas Kin1 was not involved. Our data demonstrate that just two kinesins and at least one myosin support hyphal growth.

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Enigmatic clusters of sandstone boulders on plateaus of the Stołowe Mountains (Sudetes, south-west Poland) – their geoheritage and geotouristic value

Geologos ◽

10.2478/logos-2021-0017 ◽

2021 ◽

Vol 27 (3) ◽

pp. 141-155

Author(s):

Piotr Migoń ◽

Krzysztof Parzóch

Keyword(s):

Late Cretaceous ◽

Sedimentary Rocks ◽

Long Distance ◽

Long Distance Transport ◽

South West ◽

History Of ◽

Clastic Sedimentary ◽

Distance Transport ◽

Plateau Level

Abstract Among sites of geomorphological interest in the tableland of the Stołowe Mountains, consisting of clastic sedimentary rocks of Late Cretaceous age, are enigmatic occurrences and clusters of sandstone boulders within plateau levels that are underlain by mudstones and marls. These boulders are allochthonous, having been derived from the quartz sandstone beds that support the upper plateau level and stratigraphically are in excess of 50 m above the altitudinal position of the boulders. Topographic conditions preclude long-distance transport from the escarpment slopes; boulders are hypothesised to be the last remnants of completely degraded outliers (mesas) of the upper plateau. Their present-day altitudinal position is explained by passive ‘settling’ following disintegration of caprock and denudation of the underlying weaker rocks. Two localities are here presented in detail, Łężyckie Skałki and Pustelnik, along with adjacent boulder trains in the valleys incised into the plateau. It is argued that both localities have considerable geoheritage value and both play the role of geosites, although on-site facilities are so far limited. However, the complex history of boulders sets a series of challenges for successful geo-interpretation.

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Role of Temperature and Moisture in the Production and Maturation of Gibberella zeae Perithecia

Plant Disease ◽

10.1094/pd-90-0637 ◽

2006 ◽

Vol 90 (5) ◽

pp. 637-644 ◽

Cited By ~ 34

Author(s):

N. S. Dufault ◽

E. D. De Wolf ◽

P. E. Lipps ◽

L. V. Madden

Keyword(s):

North America ◽

Water Potential ◽

Fusarium Head Blight ◽

Fusarium Graminearum ◽

Gibberella Zeae ◽

Head Blight ◽

Influence Of Temperature ◽

The Future ◽

Controlled Environments

Fusarium graminearum (teleomorph Gibberella zeae) is the most common pathogen of Fusarium head blight (FHB) in North America. Ascospores released from the perithecia of G. zeae are a major source of inoculum for FHB. The influence of temperature and moisture on perithecial production and development was evaluated by monitoring autoclaved inoculated cornstalk sections in controlled environments. Perithecial development was assessed at all combinations of five temperatures (12, 16, 20, 24, and 28°C) and four moisture levels with means (range) -0.45 (-0.18, -1.16), -1.30 (-0.81, -1.68), -2.36 (-1.34, -3.53) and -4.02 (-2.39, -5.88) MPa. Moisture levels of -0.45 and -1.30 MPa and temperatures from 16 to 24°C promoted perithecial production and development. Temperatures of 12 and 28°C and moisture levels of -2.36 and -4.02 MPa either slowed or limited perithecial production and development. The water potential of -1.30 MPa had mature perithecia after 10 days at 20°C, but not until after 15 days for 24°C. In contrast, few perithecia achieved maturity and produced ascospores at lower moisture levels (-2.36 and -4.02 MPa) and low (12°C) and high (28°C) temperatures. In the future, it may be possible to use the information gathered in these experiments to improve the accuracy of FHB forecasting systems.

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The Role of Potassium in Long Distance Transport in Plants

Vascular Transport in Plants ◽

10.1016/b978-012088457-5/50013-7 ◽

2005 ◽

pp. 221-240 ◽

Cited By ~ 16

Author(s):

Matthew V. Thompson ◽

Maciej A. Zwieniecki

Keyword(s):

Long Distance ◽

Long Distance Transport ◽

Distance Transport

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Cut and paste – Efficient cotyledon micrografting for Arabidopsis thaliana seedlings

10.1101/751677 ◽

2019 ◽

Author(s):

Kai Bartusch ◽

Jana Trenner ◽

Marcel Quint

Keyword(s):

Arabidopsis Thaliana ◽

Success Rates ◽

Long Distance ◽

Long Distance Transport ◽

Light Intensities ◽

Whole Plant ◽

Plant Level ◽

Distance Transport ◽

Plant Seedlings

AbstractCotyledon micrografting represents a very useful tool for studying the central role of cotyledons during early plant development, especially their interplay with other plant organs with regard to long distance transport. While hypocotyl grafting methods are established, cotyledon grafting is still inefficient. By optimizing cotyledon micrografting, we aim for higher success rates and increased throughput in the model species Arabidopsis thaliana. We established a cut and paste cotyledon surgery procedure on a flat solid but moist surface which improved handling of small plant seedlings. Applying a specific cutting and joining pattern throughput was increased up to 40 seedlings per hour. The combination of short day conditions and low light intensities for germination and long day plus high light intensities and vertical plate positioning after grafting significantly increased ‘ligation’ efficiency. Together, we achieved up to 46 % grafting success in A. thaliana. Reconnection of vasculature was shown by successful transport of a vasculature-specific dye across the grafting site. On a whole plant level, plants with grafted cotyledons match plants with intact cotyledons in biomass production and rosette development. This cut and paste cotyledon-to-petiole grafting protocol simplifies the handling of plant seedlings in surgery, increases the number of grafted plants per hour and produces higher success rates for A. thaliana seedlings. The developed cotyledon micrografting method is also suitable for other plant species of comparable size.

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The role of roots and rhizosphere in providing tolerance to toxic metals and metalloids

10.22541/au.162409686.68663241/v1 ◽

2021 ◽

Author(s):

Dorina Podar ◽

Frans J.M. Maathuis

Keyword(s):

Negative Impact ◽

Transport Processes ◽

Long Distance ◽

Root Cells ◽

Metals And Metalloids ◽

Natural Processes ◽

Long Distance Transport ◽

Bacteria And Fungi ◽

Distance Transport

Human activity and natural processes have led to widespread dissemination of metals and metalloids, many of which are toxic and have a negative impact on agronomic production. Roots, as the first point of contact, are essential in endowing plants with tolerance to excess metal(loid) in the soil. The most important root responses include: adaptation of transport processes that affect uptake, efflux and long distance transport of metal(loid)s; metal(loid) detoxification within root cells via conjugation to thiol rich compounds and subsequent sequestration in the vacuole; plasticity in root architecture; the presence of bacteria and fungi in the rhizosphere that impact on metal(loid) bioavailability; the role of root exudates. In this review we will provide details on these processes and assess their relevance for the detoxification of arsenic, cadmium, mercury and zinc. Furthermore, we will assess if any of these methodologies has been tested in field conditions and whether they are effective in terms of improving crop metal(loid) tolerance.

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Monitoring the Long-Distance Transport of Fusarium graminearum from Field-Scale Sources of Inoculum

Plant Disease ◽

10.1094/pdis-06-13-0664-re ◽

2014 ◽

Vol 98 (4) ◽

pp. 504-511 ◽

Cited By ~ 34

Author(s):

Aaron J. Prussin ◽

Qing Li ◽

Rimy Malla ◽

Shane D. Ross ◽

David G. Schmale

Keyword(s):

Fusarium Graminearum ◽

Logistic Regression Model ◽

Management Strategies ◽

Field Scale ◽

Head Blight ◽

Long Distance ◽

Long Distance Transport ◽

Polymorphic Microsatellites ◽

Distance Transport ◽

Clonal Isolate

The fungus Fusarium graminearum causes Fusarium head blight (FHB) of wheat. Little is known about dispersal of the fungus from field-scale sources of inoculum. We monitored the movement of a clonal isolate of F. graminearum from a 3,716 m2 (0.372 ha) source of inoculum over two field seasons. Ground-based collection devices were placed at distances of 0 (in the source), 100, 250, 500, 750, and 1,000 m from the center of the clonal sources of inoculum. Three polymorphic microsatellites were used to identify the released clone from 1,027 isolates (790 in 2011 and 237 in 2012) of the fungus. Results demonstrated that the recovery of the released clone decreased at greater distances from the source. The majority (87%, 152/175 in 2011; 77%, 74/96 in 2012) of the released clone was recaptured during the night (1900 to 0700). The released clone was recovered up to 750 m from the source. Recovery of the released clone followed a logistic regression model and was significant (P < 0.041 for all slope term scenarios) as a function of distance from the source of inoculum. This work offers a means to experimentally determine the dispersal kernel of a plant pathogen, and could be integrated into management strategies for FHB.

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Unravelling the involvement of cilevirus p32 protein in the viral transport

Scientific Reports ◽

10.1038/s41598-021-82453-4 ◽

2021 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Mikhail Oliveira Leastro ◽

Juliana Freitas-Astúa ◽

Elliot Watanabe Kitajima ◽

Vicente Pallás ◽

Jesús A. Sánchez-Navarro

Keyword(s):

Functional Study ◽

Cell Periphery ◽

Long Distance ◽

Viral Spread ◽

Long Distance Transport ◽

Viral Transport ◽

C Terminus ◽

Citrus Leprosis ◽

Distance Transport

AbstractCitrus leprosis (CL) is a severe disease that affects citrus orchards mainly in Latin America. It is caused by Brevipalpus-transmitted viruses from genera Cilevirus and Dichorhavirus. Currently, no reports have explored the movement machinery for the cilevirus. Here, we have performed a detailed functional study of the p32 movement protein (MP) of two cileviruses. Citrus leprosis-associated viruses are not able to move systemically in neither their natural nor experimental host plants. However, here we show that cilevirus MPs are able to allow the cell-to-cell and long-distance transport of movement-defective alfalfa mosaic virus (AMV). Several features related with the viral transport were explored, including: (i) the ability of cilevirus MPs to facilitate virus movement on a nucleocapsid assembly independent-manner; (ii) the generation of tubular structures from transient expression in protoplast; (iii) the capability of the N- and C- terminus of MP to interact with the cognate capsid protein (p29) and; (iv) the role of the C-terminus of p32 in the cell-to-cell and long-distance transport, tubule formation and the MP-plasmodesmata co-localization. The MP was able to direct the p29 to the plasmodesmata, whereby the C-terminus of MP is independently responsible to recruit the p29 to the cell periphery. Furthermore, we report that MP possess the capacity to enter the nucleolus and to bind to a major nucleolar protein, the fibrillarin. Based on our findings, we provide a model for the role of the p32 in the intra- and intercellular viral spread.

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Genetic Structure of Atmospheric Populations of Gibberella zeae

Phytopathology ◽

10.1094/phyto-96-1021 ◽

2006 ◽

Vol 96 (9) ◽

pp. 1021-1026 ◽

Cited By ~ 87

Author(s):

David G. Schmale III ◽

John F. Leslie ◽

Kurt A. Zeller ◽

Amgad A. Saleh ◽

Elson J. Shields ◽

...

Keyword(s):

United States ◽

Genetic Structure ◽

The United States ◽

Gibberella Zeae ◽

Genetic Identity ◽

Fixation Index ◽

Long Distance ◽

Inoculum Sources ◽

Long Distance Transport ◽

Distance Transport

Gibberella zeae, causal agent of Fusarium head blight (FHB) of wheat and barley and Gibberella ear rot (GER) of corn, may be transported over long distances in the atmosphere. Epidemics of FHB and GER may be initiated by regional atmospheric sources of inoculum of G. zeae; however, little is known about the origin of inoculum for these epidemics. We tested the hypothesis that atmospheric populations of G. zeae are genetically diverse by determining the genetic structure of New York atmospheric populations (NYAPs) of G. zeae, and comparing them with populations of G. zeae collected from seven different states in the northern United States. Viable, airborne spores of G. zeae were collected in rotational (lacking any apparent within-field inoculum sources of G. zeae) wheat and corn fields in Aurora, NY in May through August over 3 years (2002 to 2004). We evaluated 23 amplified fragment length polymorphism (AFLP) loci in 780 isolates of G. zeae. Normalized genotypic diversity was high (ranging from 0.91 to 1.0) in NYAPs of G. zeae, and nearly all of the isolates in each of the populations represented unique AFLP haplotypes. Pairwise calculations of Nei's unbiased genetic identity were uniformly high (>0.99) for all of the possible NYAP comparisons. Although the NYAPs were genotypically diverse, they were genetically similar and potentially part of a large, interbreeding population of G. zeae in North America. Estimates of the fixation index (GST) and the effective migration rate (Nm) for the NYAPs indicated significant genetic exchange among populations. Relatively low levels of linkage disequilibrium in the NYAPs suggest that outcrossing is common and that the populations are not a result of a recent bottleneck or invasion. When NYAPs were compared with those collected across the United States, the observed genetic identities between the populations ranged from 0.92 to 0.99. However, there was a significant negative correlation (R = -0.59, P < 0.001) between genetic identity and geographic distance, suggesting that some genetic isolation may occur on a continental scale. The contribution of long-distance transport of G. zeae to regional epidemics of FHB and GER remains unclear, but the diverse atmospheric populations of G. zeae suggest that inoculum may originate from multiple locations over large geographic distances. Practically, the long-distance transport of G. zeae suggests that management of inoculum sources on a local scale, unless performed over extensive production areas, will not be completely effective for the management of FHB and GER.

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