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Fungal spores are transported long distances in smoke from biomass fires

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Viable fungal spores are present in smoke from distant biomass fires. This finding has potentially important implications for prescribed burning, agricultural management and public health. While attempting to find fungal spores in dust blown from China to Texas, one of us (S.A.M.) discovered that smoke from Yucatan contains viable bacteria and fungal spores, including the genera Alternaria, Cladosporium, Fusariella and Curvularia. There was a high correlation (r2=0.78) of spores and coarse carbon particles collected on microscope slides during 13 days of the 2002 smoke season. To eliminate possible contamination by local spores, an air sampler was flown from a kite at a Texas Gulf Coast beach during and after the 2003 smoke season on days when the NOAA back trajectory showed air arriving from Yucatan. Fifty-two spores and 19 coarse black carbon particles (>2.5 μm) were collected during a 30-min kite flight on the smoke day and 12 spores and four carbons on the day without smoke. We have found spores in smoke from an Arizona forest fire and in Asian smoke at Mauna Loa Observatory, Hawaii. We have tested these findings by burning dried grass, leaves, twigs and flood detritus. The smoke from all test fires contained many spores.
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Atmospheric Environment 38 (2004) 651–655
Fungal spores are transported long distances in smoke from
biomass fires
Sarah A. Mims, Forrest M. Mims III*
Geronimo Creek Observatory, 433 Twin Oak Road, Seguin, TX 78155, USA
Received 1 October 2003; received in revised form 20 October 2003; accepted 22 October 2003
Abstract
Viable fungal spores are present in smoke from distant biomass fires. This finding has potentially important
implications for prescribed burning, agricultural management and public health. While attempting to find fungal spores
in dust blown from China to Texas, one of us (S.A.M.) discovered that smoke from Yucatan contains viable bacteria
and fungal spores, including the genera Alternaria, Cladosporium, Fusariella and Curvularia. There was a high
correlation (r2¼0:78) of spores and coarse carbon particles collected on microscope slides during 13 days of the 2002
smoke season. To eliminate possible contamination by local spores, an air sampler was flown from a kite at a Texas
Gulf Coast beach during and after the 2003 smoke season on days when the NOAA back trajectory showed air arriving
from Yucatan. Fifty-two spores and 19 coarse black carbon particles (>2.5 mm) were collected during a 30-min kite
flight on the smoke day and 12 spores and four carbons on the day without smoke. We have found spores in smoke
from an Arizona forest fire and in Asian smoke at Mauna Loa Observatory, Hawaii. We have tested these findings by
burning dried grass, leaves, twigs and flood detritus. The smoke from all test fires contained many spores.
r2003 Elsevier Ltd. All rights reserved.
Keywords: Prescribed fires; Agricultural fires; Public health; Carbon; Dust
1. Introduction
We have found that convection caused by biomass
fires can launch fungal spores and bacteria skyward,
where they may travel thousands of kilometers. While
the long-distance transport of fungal spores on currents
of air is well established (Meier and Lindbergh, 1935;
Brown and Hovmoller, 2002), we are unaware of a prior
publication that describes fire-induced convection as a
mechanism for initiating such long-distance transport.
Karnal bunt, a smut infection of wheat caused by
Tilletia indica, can spread by convection to surrounding
fields when diseased wheat is burned (Roux and
O’Brien, 2001). This disease has spread around the
world from its origin in India, and the findings reported
here suggest that fire-induced convection might spread
pathogenic spores much greater distances than sur-
rounding fields.
Sugarcane rust caused by the fungus Puccinia
melanocephala, appeared in the Dominican Republic in
July 1978. Purdy et al. (1985) suggest this outbreak
followed transoceanic transport of spores from West
Africa. Because sugarcane is burned at harvest, we
suggest that convection caused by fire could have
launched spores into the air stream that delivered
inoculum to the Caribbean. Burning of diseased plants
is so widespread, and often mandated, that there are
many similar scenarios for the launching of pathogenic
microbes by fire-induced convection.
There is an abundant literature on long-distance
transport of fungi that are pathogenic to plants and
that cause allergic reactions when inhaled by people
(Kendrick, 2000;Griffin et al., 2001;Brown and
Hovmoller, 2002). Microbes are unique among particulate
ARTICLE IN PRESS
*Corresponding author. Tel.: +1-830-372-0548; fax: +1-
830-372-2284.
E-mail address: forrest.mims@ieee.org (F.M. Mims III).
1352-2310/$ - see front matter r2003 Elsevier Ltd. All rights reserved.
doi:10.1016/j.atmosenv.2003.10.043
matter, for, unlike nonviable particles, microbes can
rapidly multiply. Thus, the transport of a small number
of pathogenic spores can result in the eventual infection
of entire fields. This phenomenon is well known and can
sometimes be forecast. For example, the North Amer-
ican Plant Disease Forecast Center at North Carolina
State University publishes on the Internet forward
trajectories of Pseudoperonospora cubensis, which causes
Downy mildew in squash, cucumbers, pumpkins, and
muskmelons, and Peronospora tabacina Adam, which
infects tobacco (Main et al., 2001). Similar forecasts
might be relevant to smoke events.
2. Fungal spores and Central American smoke
Fungal spores and bacteria are associated with dust
that originates in North Africa and reaches the
Caribbean. Griffin et al. (2001) discuss bacteria and
spores associated with Sahara dust transported across
the Atlantic. Shinn et al. (2000) describes how the soil
fungus Aspergillus in Sahara dust infects Caribbean
coral reefs. During a study in April 2002 to determine if
viable microbes are transported with dust transported
from Asia to Texas, one of us (S.A.M.) serendipitously
discovered many viable fungal spores and bacteria
associated with smoke arriving at Geronimo Creek
Observatory in South-Central Texas (29.6N, 97.9W)
from large fires in Yucatan, Mexico.
2.1. Central American smoke at Central Texas, 2002
During the April 2002 smoke event, the Navy Aerosol
Analysis and Prediction System (NAAPS) aerosol
forecast model (US Naval Research Observatory,
www.nrlmry.navy.mil/aerosol/) showed that the smoke
originating in Yucatan traveled some 1450 km and
reached Geronimo Creek Observatory in 2–3 days.
The smoke reduced visibility, increased the optical depth
measured by Sun photometers, created a pronounced
solar aureole, and caused sharp increases in the number
of 0.5 mm particles.
On 13 days during this event, a microscope slide was
placed on a 4-m meteorological tower in an open field to
collect coarse carbon particles (diameter >2.5 mm) and
spores. At local noon, two nutrient media films (3 M
Petrifilms (TM)), one formulated for bacteria (Petrifilm
Aerobic) and one for fungi (Petrifilm Yeast and Mold),
were hydrated with distilled water, exposed for 15 min
on the tower, and incubated 3 days at ambient
temperature.
Many colonies of fungi and bacteria grew on the films
exposed during the smoke episode. The microscope
slides permitted the numerical relationship of the spores
and coarse carbon particles in the smoke to be
quantified. Four scans across the width of each slide
were made, and all spores and coarse carbon particles
were counted. Fungal spores included representatives
from 22 genera, including Alternaria, Cladosporium,
Fusariella, Nigrospora, and Curvularia. As shown in
Fig. 1, the correlation of all coarse carbon particles and
spores deposited on slides during the smoke episode was
very high (r2¼0:78). However, the correlation of some
genera with carbon particles was very low (e.g., r2¼
0:00 and 0.05). These were likely local in origin.
2.2. Central American smoke at Texas Gulf Coast, 2003
Smoke from Yucatan again reached Texas during
May 2003. A passive air sampler designed by S.A.M.
was flown from a kite over a beach at North Padre
Island, Texas (27.4N, 97.3W), on days when smoke from
Yucatan was present and not present to eliminate
interference from spores originating in Texas. Fig. 2
summarizes the kite experiments.
On 3 May 2003 (Fig. 2a, c and d), NOAA back
trajectories showed that air at the Texas Gulf Coast had
passed over Yucatan 48 h earlier. Terra MODIS and
SeaWiFS imagery showed that smoke from fires in
Yucatan covered the Western Gulf of Mexico. During
the kite flight, a nearby monitoring station (CAMS 341)
operated by the Texas Commission on Environmental
Quality measured 16.1 mg/m
3
of PM 2.5 particles in air
arriving from over open water at a mean direction of
134. A 30-min flight captured 52 fungal spores and 19
coarse carbon particles (Fig. 2e).
On 5 August 2003, the NOAA back trajectory again
showed air coming from Yucatan. Terra MODIS
imagery showed no major fires in Yucatan and the
study site. During the kite flight, CAMS 341 measured
5.5 mg/m
3
of PM 2.5 particles in wind arriving from over
open water at a mean direction of 161. A 30-min flight
captured 12 fungal spores and four coarse carbon
particles (Fig. 2f).
ARTICLE IN PRESS
Fig. 1. Xy scattergraph (r2¼0:78) of fungal spores and coarse
carbon particles deposited by sedimentation on exposed
microscope slides at Geronimo Creek Observatory in South
Central Texas on all 13 days samples were collected from 25
April–10 May 2002 during a major Central American smoke
event.
S.A. Mims, F.M. Mims III / Atmospheric Environment 38 (2004) 651–655652
Spores collected by the kite sampler include many of
those collected during the 2002 Yucatan smoke event,
including the genera Alternaria, Cladosporium,Fusar-
iella and Curvularia. The kite study provides compelling
evidence that spores were present in smoke from
Yucatan arriving at the Texas Gulf Coast.
3. Fungal spores in other smoke events
We collected fungal spores in smoke from a forest fire
in Arizona (18 June 2003) and in smoke from Canada
and Louisiana at College Station, Texas (10 August
2003). We collected Alternaria and other spores and
carbon particles at Mauna Loa Observatory (MLO),
Hawaii (elevation 3400 m), during a rare Asian smoke
event (6 July 2003). The smoke formed distinct layers
and was associated with high concentrations of ozone
(>70 ppb), which were highly correlated (r2¼0:98)
with the 5 mm particle count.
4. Experimental validation of fungal spores in smoke
A simple experiment was designed to determine if
fungal spores and bacteria are present in smoke from
burning grass. Four Petrifilms (two bacteria and two
mold) were clipped to a horizontal pole and exposed to
smoke from burning grass for 5 min. A second set of
four Petrifilms was exposed to background air for 5 min.
ARTICLE IN PRESS
Fig. 2. On days when the NOAA back trajectory (a,b) indicated air arrived at North Padre Island, Texas, from Yucatan 48 h earlier
(4 May and 5 August 2003), an air sampler was flown from a kite at a Gulf Coast beach when smoke from Yucatan was present (c) and
not present (d). During 30-min flights, the sampler collected 52 spores and 19 coarse carbons on the smoke day (e), and only 12 spores
and four carbons on the nonsmoke day (f).
S.A. Mims, F.M. Mims III / Atmospheric Environment 38 (2004) 651–655 653
After 3 days of incubation at ambient temperature, the
films exposed to smoke had a total of >115 mold and
>90 bacteria colony forming units (CFUs). Those
exposed to background air had only 10 mold and eight
bacterial CFUs.
Various kinds of biomass were placed on a steel plate
in an open field and burned. Smoke from each fire was
sampled for 1 min using three Petrifilms (mold only).
The temperature of the films, which was monitored with
noncontact IR thermometry, ranged from 34Cto49
C.
Between fires, the background air was sampled for 1 min
using three Petrifilms. A wood walkway prevented
contamination by local spores. After 3 days of incuba-
tion at ambient temperature, nutrient films exposed to
smoke from all the biomass samples exhibited signifi-
cantly more CFUs than those exposed to ambient air
between burns. The ratios of total CFUs in smoke to
CFUs in background air were 9:3 (dry grass), 19:0 (dry
leaves), 48:4 (twigs) and 87:5 (flood detritus).
Our observations and photographs of test fires under
a plant canopy suggest that agitation of leaves caused by
turbulent convection (Pisaric, 2002) may dislodge
spores, which are then carried upward with the warm
plume. Nearer the ground, turbulent air rushing in to
feed the flames may also carry spores into the smoke
plume.
5. Conclusions
The common assumption that plant pathogens are
killed by burning is contradicted by the spread of Karnal
bunt to surrounding fields when wheat infected with T.
indica is burned (Roux and O’Brien, 2001). Our findings
of many fungal spores in smoke from all test fires, and
from large fires in Yucatan more than 1500 km distant,
suggest that plant pathogens might be spread consider-
ably farther than surrounding fields. Some fungal spores
we have found in smoke (e.g., Alternaria) cause allergic
reactions and trigger asthma attack (Kendrick, 2000).
Heretofore, such reactions have been attributed solely to
smoke inhalation, and we propose that fungal spores
may also play a role. We propose to test this hypothesis
by comparing emergency department visits for asthma
and allergy-related respiratory incidents with spore
counts by the Aeroallergen Monitoring Network of the
American Academy of Allergy, Asthma and Immunol-
ogy (Anon, 2001), which reveal examples of high mold
counts during smoke events. This study will also
examine incidence of asthma attack in the weeks after
major smoke events, for the progeny of spores
transported with smoke might be an even greater
problem.
Prescribed burns of diseased crops, brush, timber,
slash and rubbish may disperse large numbers of
pathogenic fungi. Major fires, which can produce smoke
plumes 3 km or more high, could be much more effective
in launching spores into the troposphere than surface
wind storms. Small burns of diseased plants and cooking
and heating with diseased firewood might disperse
pathogenic spores on a smaller scale.
A beneficial role for spores carried skyward with
forest fire smoke could be reinoculation of fire-sterilized
soil with mycorrhizal fungi and the dispersal of
such symbiotic fungi to new locations. We plan to
test this hypothesis. We also plan to study the
variety and number of spores and bacteria in smoke
from various kinds of fires. The abundance of spores
relative to coarse carbon particles, 3:1 for Yucatan
smoke in Texas and 1:1 for Asian smoke at MLO,
could have a slight influence on radiative transfer
models, for spores are regularly shaped and often
translucent, while coarse carbon is opaque, black and
irregularly shaped.
Acknowledgements
Tom Gill informed us that Central American smoke
was present when fungal spores were first found in
smoke. Mark Hartwig suggested the design hypothesis
that dispersal in smoke of mycorrhizal fungal spores
might be beneficial. John Barnes facilitated sampling at
Mauna Loa Observatory. Gabriel Solis and Ryan
Peschel assisted with test fires. Gerald Holmes informed
us about the spread of Karnal bunt by burning. We
thank those responsible for NOAA back trajectories,
GSFC MODIS imagery and the NRL NAAPS model.
We also thank Eugene Shinn for helpful discussions and
the editor and two anonymous reviewers for suggestions
that greatly improved the manuscript.
References
Anon, 2001. 2000 AAAAI Pollen and Spore Report. American
Academy of Allergy, Asthma and Immunology, Milwaukee,
WI, USA.
Brown, J.K.M., Hovmoller, M.S., 2002. Aerial dispersal of
pathogens on the global and continental scales and its
impact on plant disease. Science 297, 537–541.
Griffin, D.W., Garrison, V.H., Herman, J.R., Shinn, E.A.,
2001. African desert dust in the Caribbean atmosphere:
microbiology and public health. Aerobiologia 17, 203–213.
Kendrick, B., 2000. The Fifth Kingdom. Mycologue Publica-
tions, Sydney, BC, Canada, pp. 126–141 (http://www.
mycolog.com/).
Main, C.E., Keever, T., Holmes, G.J., Davis, J.M., 2001.
Forecasting Long-Range Transport of Downy Mildew
Spores and Plant Disease Epidemics. American Phytological
Society Net (APSnet), April–May 2001 (http://www.apsnet.
org/online/feature/forecast/).
ARTICLE IN PRESS
S.A. Mims, F.M. Mims III / Atmospheric Environment 38 (2004) 651–655654
Meier, F.C., Lindbergh, C.A., 1935. Collecting micro-organisms
from the Arctic atmosphere. The Scientific Monthly 40, 5–20.
Pisaric, M.F.J., 2002. Long-distance transport of terrestrial
plant material by convection resulting from forest fires.
Journal of Paleolimnology 28, 349–354.
Purdy, L.H., Krupa, S.V., Dean, J.L., 1985. Introduction of
sugarcane rust into the Americas and its spread to Florida.
Plant Disease 69 (8), 689–693.
Roux, C., O’Brien, O., 2001. Karnal bunt of wheat detected in
South Africa. Plant Protection News 58, 15–17 (http://
www.arc.agric.za/institutes/ppri/main/news/karnal.htm)
Shinn, E.A., Smith, G.W., Prospero, J.M., Betzer, P., Hayes,
M.L., Garrison, V., Barber, R., 2000. African dust and the
demise of Caribbean coral reefs. Geophysical Research
Letters 27 (19), 3029–3032.
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... Fungal spores can and likely do arrive aerially any time after the fire. Several well-known ascomycetes can be transported long distances by smoke plumes (Mims and Mims 2004), and recent evidence suggests that this may be a common vector for colonization into burned sites (Kobziar et al. 2018;Moore et al. 2021). Low-density propagule pools likely exist that are stimulated by heat and/or the resultant changes in soil chemistry. ...
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Phakopsora pachyrhizi is a biotrophic fungus that needs living plant tissue in order to survive. The fungus causes Asian rust on soybean and costs billions of US dollars every year for its control in South America. Despite the regulatory measure that prohibits the cultivation of soybeans in some months of the year (soybean-free period) in Brazil, the presence of soybean production areas in neighboring countries, such as Paraguay and Bolivia, may help the survival of the pathogen between crop seasons. It is known that P. pachyrhizi urediniospores can be transported thousands of kilometres by the wind. In this context, the objective of this study was to develop a mathematical model to simulate the atmospheric transport of P. pachyrhizi urediniospores from the west, Paraguay/Bolivia to Paraná/Brazil, through storms from cold fronts. The transport of urediniospores was modeled by a diffusive-convective-reactive equation. The mathematical model was discretized using the finite difference method. The algebraic system resulting from discretization was solved by the Gauss-Seidel iterative method. Wind direction and the velocity of cold fronts that crossed Paraná state between October 2018 and February 2019 were used. For validation, real cases of rust occurrence in Paraná state informed by the Anti-rust Consortium Portal in the season 2018/19 were used. A total of nine cold fronts occurred in the studied period. The wind direction varied between months. The results confirm that it is possible for urediniospores from infected areas located in a country on the west to be transported and deposited on the east, in the state of Paraná. The first case of soybean rust in Paraná was registered 10 days after the first cold front, suggesting that the transported and deposited urediniospores were still viable for host infection. This work reinforces the importance of the establishment of the soybean-free period in other soybean produced countries. The model also provides a better understanding of the pathogen's spatial dynamics, potentially enabling the correct use of fungicides.
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Blue mold of tobacco, also known as 'mildiou du tabac' in Europe(16,18,21,31,33), caused by Peronospora tabacina Adam, is a classical compound-interest plant disease that develops local as well as macroscale epidemics (4,11) (Fig. 1). The fungus is highly weather-sensitive. During periods of cool, wet, and overcast weather the disease can develop in greenhouses and/or fields and spread rapidly because of the polycyclic nature of the fungal pathogen (2,16,17). The rate of continental spread is largely determined by the potential for high levels of initial source inoculum (Fig. 2), short latent period, effective wind dispersal of spores and approximately 500,000 acres of susceptible tobacco fields across the eastern half of the United States and Canada. When the weather becomes clear, dry, and hot, the epidemic usually slows considerably or stops completely. Commercial tobacco is a seasonal crop in the temperate, humid farming zones of the Southeastern and Eastern United States, Canada, and tropical countries bordering the Caribbean basin. Following a crop-free period (winter) each year in the U.S., tobacco is exposed to asexual, windborne sporanagiospores (Fig. 3) that are believed to originate from inoculum sources of commercial winter tobacco in the tropical production zones south of the 30th parallel of latitude (22,26) and wild Nicotiana species (17,28) in the southwestern United States. It is unlikely that the fungus overwinters in the more temperate zones north of the 30th latitude because oospores have not been found in the U.S. Inoculum is therefore believed to be introduced into the U.S. anew each year (11) (Fig. 4). Further research is needed to clearly elucidate the possible role of oospores in blue mold epidemics. Research on the epidemiology and biometeorology of tobacco blue mold at N.C. State University began in 1981 following severe continent-wide epidemics in 1979 and 1980 (6,9,19). Moss and Main (27) demonstrated that a new high-temperature biotype of P. tabacina caused an early spring plant bed disease to develop into a serious summer production problem. The blue mold forecasting system was made available to all growers and the industry in 1995 (24). In 1998, a similar forecasting system for downy mildew of cucurbits was developed. Macroscale epidemics of blue mold have occurred each year since 1979 (5). The impact of these two pathogens each year largely depends upon the time of inoculum arrival and frequency of favorable weather conditions on the North American continent.
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The vitality of Caribbean coral reefs has undergone a continual state of decline since the late 1970s, a period of time coincidental with large increases in transatlantic dust transport. It is proposed that the hundreds of millions of tons/year of soil dust that have been crossing the Atlantic during the last 25 years could be a significant contributor to coral reef decline and may be affecting other ecosystems. Benchmark events, such as near synchronous Caribbean-wide mortalities of acroporid corals and the urchin Diadema in 1983, and coral bleaching beginning in 1987, correlate with the years of maximum dust flux into the Caribbean. Besides crustal elements, in particular Fe, Si, and aluminosilicate clays, the dust can serve as a substrate for numerous species of viable spores, especially the soil fungus Aspergillus. Aspergillus sydowii, the cause of an ongoing Caribbean-wide seafan disease, has been cultured from Caribbean air samples and used to inoculate sea fans.
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Air samples collected on St. John in the U.S.Virgin Islands were screened for the presenceof viable bacteria and fungi to determine ifthe number of cultivatable microbes in theatmosphere differed between ``clear atmosphericconditions'' and ``African dust-events.'' Resultsindicate that during ``African dust-events,'' thenumbers of cultivatable airborne microorganismscan be 2 to 3 times that found during ``clearatmospheric conditions.'' Direct microbialcounts of air samples using an epifluorescentmicroscopy assay demonstrated that during an``African dust-event,'' bacteria-like andvirus-like particle counts were approximatelyone log greater than during ``clear atmosphericconditions.'' Bacteria-like particles exhibitingautofluoresence, a trait of phototrophs, wereonly detected during an ``African dust-event.''
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Paleoecologists widely accept macroscopic plant remains preserved in lake sediment as good indicators of the vegetation communities growing within and adjacent to the margin of a lake or mire. However, the study of ash fallout from a small to moderate size forest fire in a low elevation Pseudotsuga menziesii/Pinus contorta/Abies lasiocarpa stand near Bozeman, Montana suggests that certain macroscopic plant remains can be transported long distances through the atmosphere. Conifer needles, pollen cones, cone scales, bracts and wood fragments were transported via the atmosphere and subsequently deposited at least 20 km from the forest fire. The majority of the plant remains that were identified were A. lasiocarpa needles. Pseudotsuga menziesii and P. contorta needles were also identified, but both were less abundant than A. lasiocarpa. The plant material that was recovered exhibited varying degrees of charring suggesting that it may be difficult to distinguish plant material that has been transported long-distances by forest fires from that which has been derived locally. Severe convection and vortices associated with intense forest fires are believed to be the primary mechanisms responsible for transporting plant material via the atmosphere.
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Some of the most striking and extreme consequences of rapid, long-distance aerial dispersal involve pathogens of crop plants. Long-distance dispersal of fungal spores by the wind can spread plant diseases across and even between continents and reestablish diseases in areas where host plants are seasonally absent. For such epidemics to occur, hosts that are susceptible to the same pathogen genotypes must be grown over wide areas, as is the case with many modern crops. The strongly stochastic nature of long-distance dispersal causes founder effects in pathogen populations, such that the genotypes that cause epidemics in new territories or on cultivars with previously effective resistance genes may be atypical. Similar but less extreme population dynamics may arise from long-distance aerial dispersal of other organisms, including plants, viruses, and fungal pathogens of humans.
Aerial dispersal of pathogens on the global and continental scales and its impact on plant disease African desert dust in the Caribbean atmosphere: microbiology and public health The Fifth Kingdom. Mycologue Publica-tions
  • J K M Brown
  • M S Hovmoller
  • D W Griffin
  • V H Garrison
  • J R Herman
  • E A Shinn
Brown, J.K.M., Hovmoller, M.S., 2002. Aerial dispersal of pathogens on the global and continental scales and its impact on plant disease. Science 297, 537–541. Griffin, D.W., Garrison, V.H., Herman, J.R., Shinn, E.A., 2001. African desert dust in the Caribbean atmosphere: microbiology and public health. Aerobiologia 17, 203–213. Kendrick, B., 2000. The Fifth Kingdom. Mycologue Publica-tions, Sydney, BC, Canada, pp. 126–141 (http://www. mycolog.com/). Main, C.E., Keever, T., Holmes, G.J., Davis, J.M., 2001
2000 AAAAI Pollen and Spore Report
  • Anon
Anon, 2001. 2000 AAAAI Pollen and Spore Report. American Academy of Allergy, Asthma and Immunology, Milwaukee, WI, USA
The Fifth Kingdom. Mycologue Publications
  • B Kendrick
Kendrick, B., 2000. The Fifth Kingdom. Mycologue Publications, Sydney, BC, Canada, pp. 126-141 (http://www. mycolog.com/).