Progress 06/19/07 to 05/21/12
Outputs
Progress Report Objectives (from AD-416): Oomycete plant pathogens cause a wide range of serious diseases of great concern to U.S. agriculture, and some are of recent emergence or reemergence. Obtaining knowledge of the biology, taxonomy, ecology, and pathology of selected diseases caused by members of this group is key to developing improved management practices and pest risk assessments which will allow damage caused by such diseases to be reduced. Our first objective is to determine basic knowledge of the biology, taxonomy, ecology, and pathology of selected Oomycete pathogens as the basis for development of improved control/management strategies and pest risk assessments. Our second objective is to determine the response of selected host species to inoculation with selected Oomycete pathogens to determine susceptibility of plant species of agricultural and commercial importance as well as naturally occurring plant species. Our proposed studies will focus on sudden oak death caused by Phytophthora ramorum and brown stripe downy mildew of maize caused by Sclerophthora rayssiae var. zeae. Attainment of our objectives will benefit U.S. agriculture by contributing new knowledge regarding biology, infectivity, spread potential, and survival ability of destructive Oomycete pathogens thus facilitating the development of improved regulatory, management, and control strategies. Approach (from AD-416): Research will be conducted utilizing specialized containment facilities to investigate critical biological factors required to develop improved identification, detection, monitoring, and management strategies for selected Oomycete plant pathogens. We will obtain isolates of selected pathogens and perform containment greenhouse, growth chamber, and laboratory experiments to elucidate their biology, taxonomy, ecology, and pathology. Pathogenicity studies will be performed on selected host plant species to determine levels of susceptibility to emerging Oomycete pathogens. A two-year study on remediation of Phytophthora ramorum-infested soil under nursery conditions was completed in California. Results showed that an experimental biological control agent consisting of Trichoderma asperellum, grown on wheat bran, was more effective in reducing P. ramorum than two other commercially available biological control products and similarly effective than a chemical control over the 12 week sampling period. Further greenhouse studies demonstrated that this experimental T. asperellum was also effective in reducing mortality of pepper plants caused by soil infestations of P. capsici. A new project was started to examine the role that endophytes might play in protecting plants from P. ramorum infection. Over 600 fungal isolates collected from leaves of rhododendron plants were screened for antagonistic activity towards P. ramorum. Over 100 isolates showed some inhibitory activity and tests have begun to isolate the compound(s) responsible for this inhibition. This may lead to novel compounds that can be used to reduce the spread of P. ramorum. A quantitative assay was developed to measure production of inoculum from roots infected with P. ramorum. This assay was initially used to study epidemiological parameters such as temperature and was then used to determine risk for eastern riparian plant species; currently it is being used to study the effects of herbicides on inoculum production (which are being used to kill infected plants in Oregon) and the effectiveness of fungicides and biological control agents in reducing inoculum levels and root colonization. This research will help in the development of management plans in wild land areas by evaluating different herbicides. It will help in the development of management plans for remediation of infected nurseries by providing methods to remediate nursery potting media and reduce plant-to-plant spread. Nurseries are the means of long-distance spread of this pathogen, and infested nurseries on the East coast are sources of inoculum in steam water. In this performance period, we also initiated studies to investigate the effect of temperatures between 5 and 30 C on germination of chlamydospores of Phytophthora ramorum. Isolates from three different P. ramorum clonal lineages were compared in replicated experiments. The total number of germinated spores was evaluated at 1, 2, 4, 6, and 8 days after plating on selective agar medium. The temperature optimum for growth for all isolates was 20 C, with little or no growth occurring at 5 or 30 C. Accomplishments 01 Control of sudden oak death. Phytophthora ramorum causes sudden oak dea and also seriously impacts the commercial nursery industry due to losses resulting from quarantine issues. The nursery industry badly needs new methods of control of P. ramorum so that infested nurseries can be remov from quarantine status and resume normal production. ARS researchers at Fort Detrick, Maryland demonstrated for the first time in a nursery setting, that the beneficial biocontrol fungus Trichoderma asperellum grown on wheat bran and raked into nursery test-plot soil, can reduce P. ramorum soil populations to non-detectable levels after 6 weeks. California regulatory agents confirmed these results at a commercial nursery, and the nursery was lifted from quarantine status. The new method will have wide applicability in reducing losses to the nursery industry due to P. ramorum, and technology transfer is underway to facilitate development of a commercial formulation of the biocontrol fungus.
Impacts
(N/A)
Publications
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Progress 10/01/10 to 09/30/11
Outputs
Progress Report Objectives (from AD-416) Oomycete plant pathogens cause a wide range of serious diseases of great concern to U.S. agriculture, and some are of recent emergence or reemergence. Obtaining knowledge of the biology, taxonomy, ecology, and pathology of selected diseases caused by members of this group is key to developing improved management practices and pest risk assessments which will allow damage caused by such diseases to be reduced. Our first objective is to determine basic knowledge of the biology, taxonomy, ecology, and pathology of selected Oomycete pathogens as the basis for development of improved control/management strategies and pest risk assessments. Our second objective is to determine the response of selected host species to inoculation with selected Oomycete pathogens to determine susceptibility of plant species of agricultural and commercial importance as well as naturally occurring plant species. Our proposed studies will focus on sudden oak death caused by Phytophthora ramorum and brown stripe downy mildew of maize caused by Sclerophthora rayssiae var. zeae. Attainment of our objectives will benefit U.S. agriculture by contributing new knowledge regarding biology, infectivity, spread potential, and survival ability of destructive Oomycete pathogens thus facilitating the development of improved regulatory, management, and control strategies. Approach (from AD-416) Research will be conducted utilizing specialized containment facilities to investigate critical biological factors required to develop improved identification, detection, monitoring, and management strategies for selected Oomycete plant pathogens. We will obtain isolates of selected pathogens and perform containment greenhouse, growth chamber, and laboratory experiments to elucidate their biology, taxonomy, ecology, and pathology. Pathogenicity studies will be performed on selected host plant species to determine levels of susceptibility to emerging Oomycete pathogens. Understanding the soil phase of P. ramorum is integral to preventing spread of the pathogen. To better understand the soil phase, an assay was used to quantify inoculum in runoff from infected plants. This assay is versatile, allowing many types of investigations to be undertaken, including determining the effect of temperature and root age on root infection and inoculum production. Here it was used to determine the relative susceptibility of various eastern riparian plant species, an important task given the repeated introduction of P. ramorum into eastern watersheds. We tested 50 plant species for susceptibility and inoculum production from roots and determined that most plants tested were not very susceptible to the pathogen or did not produce large amounts of inoculum. The assay also proved useful in determining the effect of herbicides on inoculum production from roots of treated plants, a necessary task since herbicides are being used to kill infected trees as part of Oregon's eradication effort. Because it has proved difficult to eradicate P. ramorum from infested nurseries, it is essential to find methods to disinfest nursery media. Due to the proximity of most nurseries to residential areas, use of fumigants such as methyl bromide is difficult, and other safe and effective methods must be found. Two biological control agents and a cultural control method were studied using our assay for quantifying inoculum from infected roots. This research relates to sub-objective #1A of the project. Chlamydospores of P. ramorum are thought to be a persistent form of the organism, allowing it to survive in soil. Understanding the behavior of chlamydospores will help in the cleanup of infested nurseries. In this performance period, we initiated studies to investigate the effects of plant exudates and pH on chlamydospore germination. Phytophthora kernoviae is a pathogen that is not found presently in the US; however, there is concern of its introduction. We compared sporulation ability of P. kernoviae with that of other common Phytophthora species. Sporangia production of P. kernoviae on Rhododendron, Magnolia tripetala, Liriodendron tulipifera, and Kalmia latifolia was higher than that of P. cactorum and P. syringae. Oospore production on these same hosts was similar or lower for P. kernoviae than that of the other two Phytophthora species. Our findings demonstrate that P. kernoviae, once introduced, could spread rapidly due to its prolific sporulation ability. This research relates to sub-objective #1Ca of the project. Accomplishments 01 Determined the relative susceptability of 50 riparian plant species to infection by Sudden Oak Death determined. As the Sudden Oak Death pathogen, P. ramorum, is found in more and more eastern watersheds, it i necessary to determine what native plant species might be susceptible to root infection by the pathogen, and whether such species might become significant sources of inoculum. Using an assay to quantify inoculum fro plants inoculated with P. ramorum, ARS researchers at Ft. Detrick, Maryland, were able to test 50 species for susceptibility and inoculum production from roots. We determined that most plants tested were not ve susceptible to the pathogen or did not produce great amounts of inoculum from roots, but that certain genera would be good candidates for special scrutiny, including dogwoods, and Viburnum sp. This information will be useful for regulatory agencies in developing nursery scouting protocols and for the Forest Service in performing perimeter surveys of infested nurseries. 02 Remediation of Phytophthora ramorum-infested soil using biocontrol with Trichoderma asperellum. Methods are badly needed to remediate nursery soils that are infested with the Sudden Oak Death pathogen, Phytophthora ramorum. Laboratory tests conducted by ARS researchers at Ft. Detrick, Maryland, have demonstrated that the biological control agent, Trichoder asperellum, can reduce P. ramorum soil populations to non-detectable levels within 2 to 4 weeks. We investigated whether T. asperellum is abl to reduce P. ramorum soil populations in a nursery setting. T. asperellu was selected and developed into a formulated product that could be appli to larger areas of soil and a research plot was set-up at the Dominican University of California under natural environmental conditions that simulated a commercial plant nursery. Our results show that P. ramorum declined faster in infested microplots treated with the formulated T. asperellum isolate than in non-treated control plots and plots treated with commercially-available biological control products. T. asperellum thus has the potential to be developed into a commercially available product for control of P. ramorum.
Impacts
(N/A)
Publications
- Li, P., Feng, B., Wang, H., Tooley, P.W., Zhang, X. 2011. Isolation of nine Phytophthora capsici pectin methylesterase genes which are differentially expressed in various plant species. Journal of Basic Microbiology. 51:61-70.
- Widmer, T.L. 2010. Whole plant inoculations of Viburnum species and cultivars testing for susceptibility to Phytophthora ramorum. Journal of Environmental Horticulture. 28:197-202.
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Progress 10/01/09 to 09/30/10
Outputs
Progress Report Objectives (from AD-416) Oomycete plant pathogens cause a wide range of serious diseases of great concern to U.S. agriculture, and some are of recent emergence or reemergence. Obtaining knowledge of the biology, taxonomy, ecology, and pathology of selected diseases caused by members of this group is key to developing improved management practices and pest risk assessments which will allow damage caused by such diseases to be reduced. Our first objective is to determine basic knowledge of the biology, taxonomy, ecology, and pathology of selected Oomycete pathogens as the basis for development of improved control/management strategies and pest risk assessments. Our second objective is to determine the response of selected host species to inoculation with selected Oomycete pathogens to determine susceptibility of plant species of agricultural and commercial importance as well as naturally occurring plant species. Our proposed studies will focus on sudden oak death caused by Phytophthora ramorum and brown stripe downy mildew of maize caused by Sclerophthora rayssiae var. zeae. Attainment of our objectives will benefit U.S. agriculture by contributing new knowledge regarding biology, infectivity, spread potential, and survival ability of destructive Oomycete pathogens thus facilitating the development of improved regulatory, management, and control strategies. Approach (from AD-416) Research will be conducted utilizing specialized containment facilities to investigate critical biological factors required to develop improved identification, detection, monitoring, and management strategies for selected Oomycete plant pathogens. We will obtain isolates of selected pathogens and perform containment greenhouse, growth chamber, and laboratory experiments to elucidate their biology, taxonomy, ecology, and pathology. Pathogenicity studies will be performed on selected host plant species to determine levels of susceptibility to emerging Oomycete pathogens. Our research falls within Component 2 of the National Program 303 Action Plan, and particularly to Problem Statement 2C relating to Population Dynamics, Spread, and Epidemiology of Pathogens. Under Subobjective 1A, Hypothesis 1.A.1., we determined the susceptibility of sprouted oak acorns to Phytophthora ramorum. Sprouted acorns of four different Eastern US oak species were exposed to P. ramorum concentrations of 1, 10, 100, and 1000 zoospores per ml for 24 hours. Results showed that a concentration of 1 zoospore per ml was sufficient for some infection to occur on all species. These results aid in understanding the epidemiology of P. ramorum and the data will increase the accuracy of models that examine the potential spread of this pathogen in the Eastern US. We have also examined the susceptibility of seedlings of 4 species of Eastern oak, finding that infected roots can produce inoculum, sometimes at rates equal to that of the control, Viburnum tinus. Such information is important in evaluating the risk P. ramorum poses to Eastern US oak species. Finally, in experiments exposing healthy plants of V. tinus to plants with infected roots systems under Hypothesis 1.A.2, we also demonstrated plant root-to-root spread under flooded conditions. This is the first documentation of such spread and opens up a new area of inquiry and regulatory concern within P. ramorum epidemiology. Under Hypothesis 1.C.a.5, oospores of emerging pathogen Phytophthora kernoviae were embedded in plastic screens, buried in moist sand stored at different temperatures, and tested for viability over time. Oospores were subjected to high temperatures to determine the upper temperature range for their survival. After 1 year, oospores in sand were viable at all temperatures tested up to 30oC. Oospores were no longer viable when exposed for 6 hours at 50oC or 24 hours at 40oC. This research demonstrates the long-term survival potential of P. kernoviae oospores and reveals temperature treatments that will kill oospores for use by regulators. The P. kernoviae research further supports Component 2 of the National Program 303 Action Plan which states that increased knowledge of pathogen survival is needed to develop methods for reducing the spread of disease, both domestically and internationally, and to develop integrated management practices. In further work under Subobjective 1A, chlamydospores of P. ramorum were used to infest field soil at varying densities. Chlamydospore recovery was determined by baiting with rhododendron leaf discs and dilution plating both when soil infestation was performed and following 30 days storage at 4�C, as recommended in the soil and growing medium sampling protocol recommended by USDA-APHIS. Following 30 days of infested soil storage at 4 C, P. ramorum was detected at significantly higher levels than at time 0, providing experimental evidence for the APHIS recommendations. Our research provides the benefits outlined in National Program 303 Action Plan Component 2, in that understanding these processes can lead to the development of methods that prevent disease or reduce its economic threat. Significant Activities that Support Special Target Populations Scientists in our group have participated in an activity targeting historically under-served stakeholders. In the summer of 2010, our research group hosted a student from Southern University, an 1890 School (Historically Black Land Grant Institution), for a portion of his PhD thesis work in Urban Forestry using the sudden oak death pathogen, Phytophthora ramorum. This was the second year of the project in which the student continued studies to screen southern tree species for susceptibility to P. ramorum using our facilities and under our tutelage. Accomplishments 01 Phytophthora ramorum-infested soil may be remediated by Trichoderma spp. Novel methods of control of P. ramorum in nursery production areas are badly needed to prevent serious losses currently suffered by growers in infested counties. ARS scientists at the Foreign Disease-Weed Science Research laboratory at Ft. Detrick, Maryland examined the potential sixteen Trichoderma isolates to parasitize P. ramorum propagules in soil Nine isolates showing promise for control were selected for further laboratory tests and added to P. ramorum-infested soil. Three isolates reduced P. ramorum populations to non-detectable limits after 2 to 6 wee This research demonstrates that biological control has the potential t be effective in remediating P. ramorum-infested soil and the control age has the potential to be developed into a commercial product. 02 Roots of many plant species support production of spores of Phytophthora ramorum. P. ramorum is a highly destructive pathogen that is spread within forests and nurseries via dispersal of asexual spores. ARS scientists at the Foreign Disease-Weed Science Research laboratory at Ft Detrick, Maryland evaluated 46 plant species of economic or ecological importance to the Eastern US for their ability to support root infection and production of P. ramorum spores. Counts from tested plant species we compared to those obtained from a positive control, Viburnum tinus and i was found that many species produce high numbers of P. ramorum spores. a newly recognized means of spore production and dispersal for this destructive pathogen, this information will be valuable for risk evaluation and regulatory decision-making.
Impacts
(N/A)
Publications
- Widmer, T.L. 2010. Differentiating Phytophthora spp. isolated from leaves and stems of rhododendron plants. Plant Health Progress. doi: 10.1094/PHP- 2010-0317-01-RS.
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Progress 10/01/08 to 09/30/09
Outputs
Progress Report Objectives (from AD-416) Oomycete plant pathogens cause a wide range of serious diseases of great concern to U.S. agriculture, and some are of recent emergence or reemergence. Obtaining knowledge of the biology, taxonomy, ecology, and pathology of selected diseases caused by members of this group is key to developing improved management practices and pest risk assessments which will allow damage caused by such diseases to be reduced. Our first objective is to determine basic knowledge of the biology, taxonomy, ecology, and pathology of selected Oomycete pathogens as the basis for development of improved control/management strategies and pest risk assessments. Our second objective is to determine the response of selected host species to inoculation with selected Oomycete pathogens to determine susceptibility of plant species of agricultural and commercial importance as well as naturally occurring plant species. Our proposed studies will focus on sudden oak death caused by Phytophthora ramorum and brown stripe downy mildew of maize caused by Sclerophthora rayssiae var. zeae. Attainment of our objectives will benefit U.S. agriculture by contributing new knowledge regarding biology, infectivity, spread potential, and survival ability of destructive Oomycete pathogens thus facilitating the development of improved regulatory, management, and control strategies. Approach (from AD-416) Research will be conducted utilizing specialized containment facilities to investigate critical biological factors required to develop improved identification, detection, monitoring, and management strategies for selected Oomycete plant pathogens. We will obtain isolates of selected pathogens and perform containment greenhouse, growth chamber, and laboratory experiments to elucidate their biology, taxonomy, ecology, and pathology. Pathogenicity studies will be performed on selected host plant species to determine levels of susceptibility to emerging Oomycete pathogens. Significant Activities that Support Special Target Populations To identify potential biocontrol agents for the sudden oak death pathogen, Phytophthora ramorum, ten candidate microorganisms were applied to the foliage of Rhododendron cuttings which were then inoculated with P. ramorum. We compared the resulting necrosis to that produced on cuttings treated with a fungicide. Three isolates displayed good protection, with one isolate not significantly different than the fungicide. Work is continuing to investigate the rate of antagonist needed for protection, the length of time the antagonist is effective, and whether the antagonists are effective against different lineages of P. ramorum. Screening of 25 different species and cultivars of Viburnum for their susceptibility to P. ramorum has been completed. Results showed a wide range in susceptibility with no species or cultivar being completely resistant, and that evergreen species or cultivars that are more susceptible than deciduous species. Sprouted acorns of six Quercus species, common to the eastern U.S., were tested for their susceptibility towards P. ramorum. All species were susceptible to P. ramorum zoospores with as little as 1 hour exposure time. A study has been completed on the survival of P. kernoviae oospores in sand at different temperatures. Results showed that even at 30 degrees C, oospores were viable after 1 year in sand. A study was also completed determining the optimal method for production of viable P. kernoviae oospores. An assay developed for quantifying inoculum present in runoff from Phytophthora-infected-plants was used for basic epidemiology studies and applied risk assessments. Work continued on a long-range study of root-infected Rhododendrons. Work continued on evaluating the longevity of chlamydospores of P. ramorum incubated in soil at different temperatures and assayed by direct plating and polymerase chain reaction (PCR). Work continued on evaluating a soil biofumigant as a means of remediation of P. ramorum- infested soil. Work also continued on research to determine whether soil constituents can influence spore germination of P. ramorum chlamydospores. Final experiments were completed in a project to adapt and optimize a previously described mitochondrial based real-time PCR assay for use with a Cepheid SmartCycler. Work was also completed on a study to assess risk of spread of P. ramorum on common container weeds of nursery plants. The effect of moisture period (up to 6 days dew) on foliar disease development in northern red oak and chestnut oak was assessed along with the propensity of P. ramorum to form sporangia and chlamydospores on these two potential host species. Smaller lesion areas were produced on northern red oak compared with chestnut oak but on a per-leaf basis, the two species did not differ. Northern red oak sustained a far higher density of spores per lesion than did chestnut oak, and significantly more chlamydospores were produced on northern red oak than on chestnut oak. Knowledge of the sporulation potential of P. ramorum on these two valuable Eastern forest species enhances our ability to predict the epidemiological impact should the disease become established in the Eastern US. Technology Transfer Number of New/Active MTAs(providing only): 1
Impacts
(N/A)
Publications
- Widmer, T.L. 2008. Comparing necrosis of Rhododendron leaf tissue inoculated with Phytophthora ramorum sporangia or zoospores. Plant Disease. 93:30-35.
- Tooley, P.W., Browning, M.E. 2009. Susceptibility of some common Eastern forest understory plant species to Phytophthora ramorum. Plant Disease. 93:249-256.
- Tooley, P.W., Browning, M.E., Kyde, K.L., Berner, D.K. 2009. The effect of temperature and moisture period on infection of Rhododendron Cunningham�s White by Phytophthora ramorum. Phytopathology. 99:1045-1052.
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Progress 10/01/07 to 09/30/08
Outputs
Progress Report Objectives (from AD-416) Oomycete plant pathogens cause a wide range of serious diseases of great concern to U.S. agriculture, and some are of recent emergence or reemergence. Obtaining knowledge of the biology, taxonomy, ecology, and pathology of selected diseases caused by members of this group is key to developing improved management practices and pest risk assessments which will allow damage caused by such diseases to be reduced. Our first objective is to determine basic knowledge of the biology, taxonomy, ecology, and pathology of selected Oomycete pathogens as the basis for development of improved control/management strategies and pest risk assessments. Our second objective is to determine the response of selected host species to inoculation with selected Oomycete pathogens to determine susceptibility of plant species of agricultural and commercial importance as well as naturally occurring plant species. Our proposed studies will focus on sudden oak death caused by Phytophthora ramorum and brown stripe downy mildew of maize caused by Sclerophthora rayssiae var. zeae. Attainment of our objectives will benefit U.S. agriculture by contributing new knowledge regarding biology, infectivity, spread potential, and survival ability of destructive Oomycete pathogens thus facilitating the development of improved regulatory, management, and control strategies. Approach (from AD-416) Utilize specialized plant pathogen containment facilities to investigate and characterize biology, taxonomy, ecology, and pathology of selected Oomycete diseases considered to be a threat to the U.S. Maintain isolates of exotic and emerging endemic Oomycete pathogens and elucidate factors related to their life cycles, host range, infectivity, and survival characteristics. Assess factors critical in epidemiology of diseases caused by exotic and emerging Oomycetes using a variety of scientific methods and approaches. Significant Activities that Support Special Target Populations For our first objective, we performed in vitro assays that have identified ten different soil and epiphytic leaf microorganisms that are inhibitory towards the sudden oak death pathogen, P. ramorum. Three isolates have been chosen for further testing on whole plants. Formulations for application of the antagonists have been tested to study their impact on spore germination, growth, sporulation and host toxicity. In addition, five endophytes from Viburnum cultivars showed in vitro inhibition towards P. ramorum growth. Work is progressing on developing tissue culture plants of Rhododendron and Viburnums to test these endophytes. Four Trichoderma asperellum isolates were also selected for further testing based upon their in vitro mycoparasitism against P. ramorum. Tests have been started to determine if adding T. asperellum to P. ramorum-infested soil or infected leaves will remove the pathogen from the infested material. We also demonstrated the presence of P. ramorum sporangia on infected roots and chlamydospores in infected host plant roots. We showed that sporangia of P. ramorum can be detected in runoff from plants with root infections. Spread of the pathogen from nursery sites to natural areas through contaminated runoff has been observed in Florida and Mississippi. There is also uncertainty about the role of chlamydospore dormancy in the long-term survival of P. ramorum. We studied vital staining to determine the status of non-germinating chlamydospores, and found that fluorescein diacetate derivatives show promise in determining whether spores are living or dead. We adapted and optimized a real-time polymerase chain reaction (PCR) assay to detect P. ramorum, for use with a Cepheid 'SmartCycler' machine, the type of machine used by many university and state laboratories whose job is pathogen detection. This work will allow these groups to use our assay, which targets a DNA sequence different from that used in other PCR assays. The assay we developed can be used alone or with other assays to provide a secondary determination for borderline samples. We have developed techniques for producing oospores and of P. kernoviae, a foreign pathogen which is a threat to U.S. forests. Studies of oospore maturation are also in progress. We have initiated a long term experiment to examine the impact of high and low temperatures on the survival of P. kernoviae oospores and data have been collected at the three month time point. In addressing our second objective, we have nearly completed screening of over twenty cultivars of Viburnum for their susceptibility to P. ramorum. In addition, we have screened 25 plant species which comprise part of the understory of Eastern oak forests for their susceptibility to P. ramorum and evaluated the propensity for the pathogen to sporulate on each species. This information will be of use in attempts to survey Eastern US forest regions for the presence of P. ramorum, and in pest risk assessments. NP 303 Component 2, Problem Statement 2C. Technology Transfer Number of New/Active MTAs(providing only): 1 Number of Other Technology Transfer: 2
Impacts
(N/A)
Publications
- Browning, M.E., Englander, L., Tooley, P.W., Berner, D.K. 2008. Survival of Phytophthora ramorum hyphae following exposure to temperature extremes and various humidities. Mycologia. 100:236-245.
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