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Research of peach fungal gummosis (PFG), which is a vascular disease caused by fungi in the Botryosphaeriaceae family, is particularly important in the southeastern United States, southern China, South Africa, and Western Australia. This disease has been a significant concern for the peach industry in the southeastern United States since the 1970s. The changing climatic conditions in the prunus production areas of the world have worsened the severity of PFG disease. A study of the morphological and genetic profiles of Botryosphaeriaceae species from diseased peach trees found four species in Georgia, Florida, Alabama, and South Carolina. Botryosphaeria dothidea, Lasiodiplodia theobromae, Diplodia seriata, and Neofusicocoum parvum were isolated and identified using conidiospore characters and rDNA sequences of internal transcribed spacer regions and elongation factor α-1 genes. B. dothidea was the most common species from diseased peach trees. A significant implication of this research is the potential resistance in Prunus germplasm, which was genotyped for the resistance locus Botd8 and evaluated for relative susceptibility to one isolate each from B. dothidea, L. theobromae, and D. seriata. Pathogenicity evaluations of peach, almond, and interspecific hybrids used detached stem and leaf assays for susceptibility to PFG based on lesion lengths and gumming scores. L. theobromae inoculation resulted in the most extensive lesions on stems and leaves. Detached stem and leaf assays indicated that Prunus with the Botd8 locus significantly differed in lesion size when infected with B. dothidea and D. seriata. However, the resistant locus had no significant effect on the relative susceptibility of Prunus to L. theobromae. Field and detached stem and leaf assays identified almond cultivars Pioneer and Golden State and Peach × Almond hybrids with Botd8 (+) as tolerant to PFG. Correlations between detached assays and field gumming scores suggested that inoculations on detached stems or leaves under controlled conditions can be used to preliminarily screen for resistance to PFG. These detached assays for specific pathogen isolates provide an opportunity for a relatively fast, nondestructive evaluation of Prunus germplasm and are tools that can be used to identify the components of disease resistance.

Invasive plants, which cause substantial economic and ecological impacts, acquire both pathogens and beneficial microbes in their introduced ranges. Communities of fungal endophytes are known to mediate impacts of pathogens on plant fitness but few studies have examined the temporal dynamics of fungal communities on invasive plants. The annual grass Microstegium vimineum, an invader of forests and riparian areas throughout the eastern United States, experiences annual epidemics of disease caused by Bipolaris pathogens. Our objective was to characterize the dynamics of foliar fungal communities on M. vimineum over a growing season during a foliar disease epidemic. First, we asked how the fungal community in the phyllosphere changed over 2 months that corresponded with increasing disease severity. Second, we experimentally suppressed disease with fungicide in half of the plots and asked how the treatment affected fungal community diversity and composition. We found increasingly diverse foliar fungal communities and substantial changes in community composition between timepoints using high-throughput amplicon sequencing of the internal transcribed spacer 2 region. Monthly fungicide application caused shifts in fungal community composition relative to control samples. Fungicide application increased diversity at the late-season timepoint, suggesting that it suppressed dominant fungicide sensitive taxa and allowed other fungal taxa to flourish. These results raise new questions regarding the roles of putative endophytes found in the phyllosphere given the limited number of pathogens known to cause disease on M. vimineum in its invasive range.

Roots serve the vital function of water and nutrient uptake for plants. Healthy roots provide the foundation for productive blueberry bushes and require the right horticultural inputs and soil environment to thrive. Less-than-ideal conditions can result in unhealthy, rotten roots, sometimes caused by disease. The most common and destructive root rot disease of southern highbush blueberry (SHB) in Florida is Phytophthora root rot (PRR), caused by the oomycete pathogen Phytophthora cinnamomi Rands. Oomycetes, or “water molds,” favor water-saturated environments. The distinction between oomycetes and fungi is important for disease management, because many fungicides work for only one group, not both. Worldwide, P. cinnamomi is a devastating pathogen of approximately 5,000 woody plant host species. For blueberry growers in Florida, PRR is a persistent problem that is currently managed through careful site selection, preparation, and routine Phytophthora-specific fungicide applications.

The pathogen Xylella fastidiosa is a xylem-restricted, gram-negative bacterium that is known to cause diseases of many cultivated plant species. Recent outbreaks of X. fastidiosa diseases in Europe have brought attention to the impact of this pathogen, especially to perennial crops. Among the Prunus genus, X. fastidiosa is known to have a wide range of hosts, including plum, almond, peach, cherry, and apricot. Infected trees have reduced fruit quality, possibly resulting in unmarketable fruits, as well as reduced lifespan. There are no curative management options for X. fastidiosa diseases in Prunus; therefore, development of resistant or tolerant cultivars through breeding represents an efficient option to reduce the impact of this pathogen. In this context, the main objective of this study was to determine the occurrence of X. fastidiosa in germplasm of the Stone Fruit Breeding Program at the University of Florida located in Gainesville, FL, USA, under natural infection conditions. A total of 43 individuals representing 10 different genotypic groups within the Prunus genus were tested for the presence of X. fastidiosa. Additionally, we report a novel and easy sampling method using sawdust collected from tree trunks for the detection of this pathogen in Prunus and the development of an endogenous control for improving the diagnosis of this pathogen using real-time polymerase chain reactions. Our results showed a high incidence of X. fastidiosa in the germplasm tested, with more than 65% of the samples positive for the presence of the bacterial pathogen. However, X. fastidiosa was not detected in most of the P. mume samples tested, whereas almost all the P. mume × P. armeniaca hybrids were positive. Negative individuals were also identified in P. avium, P. campanulata, P. umbellata, and P. salicina × P. ceracifera. These trees have been planted in the field, exposed to natural infection for 4 to 11 years, and are considered to show field resistance. Finally, primers and probes based on the Prunus COX gene developed in this study can be used as an internal amplification control to enhance the interpretation of results of X. fastidiosa detection assays using sawdust samples.

The weather conditions favoring Blueberry anthracnose fruit rot disease incidence and development can be difficult to predict, and it can significantly impact yield under conducive weather patterns. For that reason, the authors of this new 6-page publication of the UF/IFAS Plant Pathology Department developed and validated a web-based disease alert system for blueberry AFR, the Blueberry Advisory System (BAS), to help blueberry growers in Florida identify weather conditions favorable for the disease and improve disease management. Written by André B. Gama, Douglas A. Phillips, Vinícius A. Cerbaro, Phillip F. Harmon, Clyde W. Fraisse, and Natalia A. Peres. https://edis.ifas.ufl.edu/pp366

In recent decades, increasing attention has been paid to food safety and organic horticulture. Thus, people are looking for natural products to manage plant diseases, pests, and weeds. Essential oils (EOs) or EO-based products are potentially promising candidates for biocontrol agents due to their safe, bioactive, biodegradable, ecologically, and economically viable properties. Born of necessity or commercial interest to satisfy market demand for natural products, this emerging technology is highly anticipated, but its application has been limited without the benefit of a thorough analysis of the scientific evidence on efficacy, scope, and mechanism of action. This review covers the uses of EOs as broad-spectrum biocontrol agents in both preharvest and postharvest systems. The known functions of EOs in suppressing fungi, bacteria, viruses, pests, and weeds are briefly summarized. Related results and possible modes of action from recent research are listed. The weaknesses of applying EOs are also discussed, such as high volatility and low stability, low water solubility, strong influence on organoleptic properties, and phytotoxic effects. Therefore, EO formulations and methods of incorporation to enhance the strengths and compensate for the shortages are outlined. This review also concludes with research directions needed to better understand and fully evaluate EOs and provides an outlook on the prospects for future applications of EOs in organic horticulture production.

Abstract Plant litter can alter ecosystems and promote plant invasions by altering resource availability, depositing phytotoxins, and transmitting microorganisms to living plants. Transmission of microorganisms from invasive plant litter to live plants may gain importance as invasive plants, which often escape pathogens upon introduction to a new range, acquire new pathogens over time. It is unclear, however, if invasive plant litter affects native plant communities by promoting disease. Microstegium vimineum is an invasive grass that suppresses native populations, in part through litter production, and has acquired new fungal leaf spot diseases since its introduction to the United States. In a greenhouse experiment, we evaluated how M. vimineum litter and its pathogens mediated competition with the native grass Elymus virginicus. M. vimineum litter promoted disease on E. virginicus and suppressed establishment and biomass of both species. Litter had stronger negative effects on E. virginicus than M. vimineum, increasing the relative biomass of M. vimineum. Live plant competition reduced biomass of both species and live M. vimineum increased disease incidence on E. virginicus. Altogether, invasive grass litter suppressed both species, ultimately favoring the invasive species in competition, and increased disease incidence on the native species.

Abstract Vaccinium arboreum Marsh is a small tree adapted to low-organic matter soils and is one of the few ericaceous species that tolerates soil pH greater than 6.0. It has a deep root system and is more drought tolerant than cultivated blueberry. The use of V. arboreum as a rootstock for commercial blueberry production has been studied previously in young blueberry plantings. The objective of the current study was to expand on earlier work and evaluate growth, productivity, and tolerance to bacterial leaf scorch (Xylella fastidiosa) in established plantings of own-rooted vs. grafted southern highbush blueberry (SHB). Two field plantings of grafted and own-rooted ‘Meadowlark’ and ‘Farthing’ SHB were established in May 2011: one at the University of Florida–Institute of Food and Agricultural Sciences (UF-IFAS) Plant Science Research and Education Unit in Citra, FL, and the other at a commercial blueberry farm in Archer, FL. At both sites, four rootstock–scion combinations were grown in either pine bark-amended or nonamended soil. Canopy volume was greater in grafted compared with own-rooted ‘Meadowlark’ at both locations throughout the 4 years of the study (2015–18), whereas canopy volume in ‘Farthing’ was not consistently different. For both cultivars and both locations, canopy volume was greater on amended compared with nonamended soil. Although canopy growth was not consistently increased in the grafted compared with own-rooted plants, yield was greater in grafted plants of both cultivars at both locations. Cumulative yield over the 4 years was similar between grafted plants grown on both amended and nonamended soil, and was significantly greater than yield of own-rooted plants on nonamended soil, suggesting the use of this rootstock may decrease the requirement for pine bark amendment. In general, grafted plants produced larger berries, with no negative impacts on fruit soluble solids, titratable acidity, or firmness. ‘Meadowlark’—an SHB cultivar that exhibits high sensitivity to bacterial leaf scorch—displayed decreased development of bacterial leaf scorch symptoms when grafted onto V. arboreum compared with own-rooted plants. These results indicate the potential benefits of grafting SHB onto V. arboreum rootstock, particularly under marginal soil conditions. However, a complete economic analysis that also takes into account any differences in longevity between the two systems must be done to determine whether the benefits of using grafting are feasible financially for the grower.

Bark inclusions are an understudied structural defect in trees and shrubs. They consist of areas of bark on adjacent parts of stems or scaffolds, typically on the inner faces of a narrow fork, which become overgrown and internalized to occupy part of the wood between the stems. Here, bark inclusions are described for the first time to occur in cane unions at the crown of southern highbush blueberry (Vaccinium corymbosum interspecific hybrids) cultivars ‘Farthing’ and ‘Meadowlark’, both of which are characterized by a narrow, vase-shaped architecture at the base of the plant, leading to crowding of the canes. When affected canes were dissected at their bases, bark inclusions were visible internally as a line of compressed bark within the wood of adjoining canes, or as bark invaginations and fissures across part of or the entire cross-section of the cane. Externally, blueberry crowns with included bark were characterized by either an inward ridgeline of bark between canes of similar diameters emerging from the crown at a narrow angle from each other, or by the presence of girdling roots. Bark inclusions were observed in plants of all ages, from the nursery to mature production fields. The internal length of the bark inclusion correlated strongly with the external length of the inward stem bark ridgeline symptom as measured by destructive sampling in the field (r = 0.916, p < 0.0001, n = 20). When plants with and without bark inclusions were subjected to a winch test in the field, the probability of breakage for canes without included bark was significantly lower (p < 0.0002) than for those with included bark, and at the maximum applied force of 972.4 N, 95.2% of the canes with bark inclusions failed (i.e., broke at the crown), compared with only 52.6% for canes without included bark. In a survey across three fields, the number of bark inclusions per plant was significantly associated with an index of cane crowding (r = 0.286. p = 0.0267, n = 60), suggesting that plants with tight, crowded bases had more bark inclusions. In addition, there was a significant association (p < 0.0001) between the presence or length of bark inclusions and the intensity of Botryosphaeria stem blight in these fields. This study showed that bark inclusions occur commonly in certain southern highbush blueberry cultivars in the production conditions of Georgia and Florida, with negative implications for cane integrity and plant health.

Blueberry (Vaccinium spp.) plants are exposed to existing and emerging viruses as a result of expanding acreage of blueberry plantations across the world, primarily in North America. Since blueberry is cultivated in areas where there are wild Vaccinium spp., there is increasing risk of virus movement between wild and cultivated blueberries. This is theoretically possible because viruses can spread from commercial cultivars to native species and vice versa causing the spread of existing and new viruses. The occurrence of these viruses in blueberry can be devastating to the industry considering the cost for cultivation and production of this perennial crop. However, the advent of high-throughput sequencing and bioinformatic sequence analysis have allowed for rapid identification of known and novel viruses in any crop including blueberry, thus facilitating proper intervention in response to serious viral diseases. In this paper, we aim to focus on the current status of known and novel viruses emerging in blueberry worldwide, which may impact the blueberry industry.

Southern highbush blueberry (SHB) cultivars are commercially grown throughout much of Florida, in both deciduous and evergreen production systems. In both systems, leaves can be damaged by many factors including environmental conditions, chemical applications, insects, and diseases. This new 12-page publication of the UF/IFAS Plant Pathology Department includes basic information to assist growers in determining 1) the likely cause (fungal, viral, algal, or bacterial) of leaf symptoms, 2) when specific leaf spots are likely to occur, 3) characteristic symptoms of common leaf problems, and 4) some of the management options that are available. Written by Douglas A. Phillips, Norma C. Flor, and Philip F. Harmon. http://edis.ifas.ufl.edu/pp348

Botryosphaeria stem blight is the most common and damaging fungal vascular disease on southern highbush blueberry in the southern United States, causing stem and cane dieback and reductions in yield. Advanced stages of this disease may cause premature plant death, which results in significant replanting costs for growers. Biotic or abiotic stresses from a variety of sources can make plants more susceptible to infection by stem blight pathogens. This new 5-page publication is intended for Florida blueberry growers to use as a guide in the identification and management of Botryosphaeria stem blight on southern highbush blueberry. Written by Norma C. Flor, Douglas A. Phillips, and Philip F. Harmon and published by the UF/IFAS Plant Pathology Department. http://edis.ifas.ufl.edu/pp347

Southern highbush blueberry (interspecific hybrids of Vaccinium corymbosum L.) is cultivated near wild V. corymbosum as well as closely related species in Florida, USA. The expansion of blueberry cultivation into new areas in Florida and deployment of new cultivars containing viruses can potentially increase the diversity of viruses in wild and cultivated V. corymbosum. In this study, viral diversity in wild and cultivated blueberries (V. corymbosum) is described using a metagenomic approach. RNA viromes from V. corymbosum plants collected from six locations (two cultivated and four wild) in North Central Florida were generated by high throughput sequencing (HTS) and analyzed using a bioinformatic analysis pipeline. De novo assembled contigs obtained from viromes of both commercial and wild sites produced sequences with similarities to plant virus species from a diverse range of families (Amalgaviridae, Caulimoviridae, Endornaviridae, Ophioviridae, Phenuiviridae, and Virgaviridae). In addition, this study has enabled the identification of blueberry latent virus (BlLV) and blueberry mosaic associated ophiovirus (BlMaV) for the first time in Florida, as well as a tentative novel tepovirus (blueberry virus T) (BlVT) in blueberry. To the best of our knowledge, this is the first study that compares viral diversity in wild and cultivated blueberry using a metagenomic approach.

This 38-page publication provides current information on pest, disease, and weed management, and plant growth regulator use for commercial blueberries in Florida. It is a minor revision written by Jeffrey G. Williamson, Philip F. Harmon, Oscar E. Liburd, and Peter Dittmar, and published by the Horticultural Sciences Department, September 2018. HS1156/HS380: 2022 Florida Blueberry Integrated Pest Management Guide (ufl.edu)

Peach rust is a fungal disease commonly caused by Tranzchelia discolor (Fuckel) Tranzschel & Litvinov that attacks plants in the genus Prunus, including peach, nectarine, almond, plum, apricot, and cherry. In the Southeastern United State, the fungus is most common on peach orchards during summer and fall. The peach rust severity depends on the climatic conditions (temperature and rainfall), hosts (peach cultivars) and geographic location. Fungus rust is spread by airborne spores, which depend on moisture for infection. Where warm temperatures and high rainfalls usually result in severe peach rust infections. Florida’s summer rainfall provide favorable conditions for peach rust development. Despite, all currently available cultivars of peach in Florida are susceptible to the disease (Adaskaveg et al. 2012). Further studies of subtropical peach cultivars have shown differences for peach rust tolerance, measured by leaf retention, and rust incidence in the orchards (Alves et al. 2014; Citadin et al. 2010)

Information contained in this 4-page publication is intended for Florida blueberry growers to use as a guide in the identification of anthracnose, a group of fungal pathogens that affects a wide range of plants, including southern highbush blueberries (SHB). Written by Douglas A. Phillips, Maria C. Velez-Climent, Philip F. Harmon, and Patricio R. Munoz and published by the UF/IFAS Plant Pathology Department, May 2018. https://edis.ifas.ufl.edu/pp337

Bacterial wilt is a newly discovered disease of blueberry in Florida. Plants with bacterial wilt will show signs of water stress such as wilting and marginal leaf burn. The disease was initially confirmed on three farms in Florida. This 3-page fact sheet describes the symptoms, occurrence, and management of bacterial wilt in blueberry. Written by Philip F. Harmon, Carrie Harmon, and Dave Norman, and published by the Plant Pathology Department, November 2016. PP332/PP332: Bacterial Wilt of Southern Highbush Blueberry Caused by Ralstonia solanacearum (ufl.edu)

This revised 37-page fact sheet provides extensive information about integrated pest management for growing blueberry plants in Florida. Written by Jeffrey G. Williamson, Philip F. Harmon, Oscar E. Liburd, and Peter Dittmar, and published by the Horticultural Sciences Department, March 2016. HS1156/HS380: 2022 Florida Blueberry Integrated Pest Management Guide (ufl.edu)

Recommendations are based on information from the manufacturer’s label and performance data from research and Extension field tests. This 31-page pest management guide was adapted for Florida by Jeffrey G. Williamson, Philip F. Harmon, Oscar E. Liburd, and Peter Dittmar, from the Southeast Regional Blueberry Integrated Management Guide, and published by the UF Department of Horticultural Sciences, November 2012. HS1156/HS380: 2022 Florida Blueberry Integrated Pest Management Guide (ufl.edu)

Florida’s warm, humid environment is a gardener’s paradise and a great location for ornamental plant producers to grow numerous plant species—but these conditions also are suitable for the development of a wide variety of plant pathogens and insects that can spread them. Florida is also a major port of entry for the international trade of ornamental plants, which carries the risk of introducing exotic invasive pathogens, so growers are required to follow certain phytosanitory regulations. These challenges require growers to develop the most efficient production plans possible, incorporating as many tactics as they can to maximize plant health and minimize opportunities for pest and disease outbreaks—a concept known as integrated pest management (IPM). This revised 16-page fact sheet is intended to be used by growers, landscape professionals, and other pest control operators as a reference for managing ornamental plant diseases. Written by P. F. Harmon and S. D. Bledsoe, and published by the UF Department of Plant Pathology, June 2012. PP-202/PP123: Professional Disease Management Guide for Ornamental Plants (ufl.edu)

Fairy rings, especially the mushrooms, are most commonly observed during the summer months, when Florida receives the majority of its rainfall. This revised 2-page fact sheet with identification and control information was written by M. L. Elliott and P. F. Harmon, and published by the UF Department of Plant Pathology, February 2011. SS-PLP-7/LH046: Fairy Rings (ufl.edu)

Identify and control for this disease that often appears as reddish-brown spots surrounded by a narrow yellow halo, primarily in centipedegrass. This revised 2-page fact sheet was written by M. L. Elliott and P. F. Harmon, and published by the UF Department of Plant Pathology, February 2011. SS-PLP-56/LH043: Anthracnose (ufl.edu)

This fungal disease is most serious on bermudagrass and acts over a wide range of temperatures. This revised 2-page fact sheet was written by M. L. Elliott and P. F. Harmon, and published by the UF Department of Plant Pathology, February 2011. SS-PLP-9/LH048: Helminthosporium Leaf Spot (ufl.edu)

This disease affects primarily St. Augustinegrass, but also centipedegrass. It is most often observed from late spring to early fall, especially during prolonged periods of rainfall. This revised 2-page fact sheet was written by M. L. Elliott and P. F. Harmon, and published by the UF Department of Plant Pathology, February 2011. PP204/LH047: Gray Leaf Spot of St. Augustinegrass: Cultural and Chemical Management Options (ufl.edu)

This fungal root disease affecting all warm season turfgrasses is associated with wet soil conditions and causes nonspecific decline in turf quality. This revised 2-page fact sheet was written by M. L. Elliott and P. F. Harmon, and published by the UF Department of Plant Pathology, February 2011. SS-PLP-11/LH050: Pythium Root Rot (ufl.edu)

Turfgrass diseases are underappreciated because the biological organisms (plant pathogens) causing the problems are rarely observed. Fortunately, grasses maintained using proper cultural practices (water, mowing, and fertility) are not as likely to become diseased or be as severely damaged as grasses that do not receive proper care. This 11-page revised fact sheet discusses turfgrass diseases, their causal agents, diagnosis, and management. Written by M. L. Elliott and P. F. Harmon and published by the UF Department of Plant Pathology, February 2011. SSPLP14/LH040: Turfgrass Disease Management (ufl.edu)

Rust is a fungal disease that occurs in cool weather causing yellow specks enlarging to spots with orange pustules in St. Augustinegrass and zoysiagrass. This revised 2-page fact sheet was written by M. L. Elliott and P. F. Harmon, and published by the UF Department of Plant Pathology, February 2011. SS-PLP-12/LH051: Rust (ufl.edu)

Cercospora leaf spot is a fungal disease of St. Augustinegrass observed during periods of frequent rainfall. This revised 2-page fact sheet was written by M. L. Elliott and P. F. Harmon, and published by the UF Department of Plant Pathology, February 2011. SS-PLP-57/LH082: Cercospora Leaf Spot (ufl.edu)

PP-256, a 6-page illustrated fact sheet by Philip F. Harmon, Carrie L. Harmon, Aaron J. Palmateer, and Stephen H. Brown, presents information on four representative rust diseases of ornamentals, including gladiolus rust, daylily rust, frangipani rust, and guava rust. Includes references. Published by the UF Department of Plant Pathology, May 2009. PP256/PP172: Rusts on Ornamentals in Florida (ufl.edu)

HS-1156 is a 35-page illustrated guide adapted for Florida from the Southeast Regional Blueberry Integrated Management Guide by Jeffrey G. Williamson, Philip F. Harmon, and Oscar E. Liburd. Primarily tabular in format, it also includes links to additional resources, text descriptions of key pests by stages of flower bud development, and an illustrated guide to recognized stages. Published by the UF Department of Horticultural Science, March 2008. HS1156/HS380: 2022 Florida Blueberry Integrated Pest Management Guide (ufl.edu)

Revised! RF-SR007, an 8-page guide by A.J. Palmateer, C.M. Stiles, P.D. Roberts, R.E. Cullen, H. Dankers, R.J. McGovern, N. Peres, P.F. Harmon, and C.L. Harmon, provides extension clientele with the information they need to submit plant samples to Florida Extension Plant Diagnostic Clinics. Published by the UF Department of Plant Pathology, May 2008. RFSR007/SR007: Sample Submission Guide for Plant Diagnostic Clinics of the Florida Plant Diagnostic Network (ufl.edu)

PP-244, a 3-page illustrated fact sheet by R.A. Cating, A.J. Palmateer, C.M. Stiles, P.F. Harmon, and D.A. Davison, describes this physiological disorder of orchids caused by overwatering, symptoms, diagnosis, and management. Published by the UF Department of Plant Pathology, November 2007.

PP-235, a 4-page illustrated fact sheet by Wayne M. Jurick II, Dario F. Narvaez, Carrie L. Harmon, James J. Marois, David L. Wright, and Philip F. Harmon, describes this fungal plant disease new to the US since 2004, its symptoms, causal organism, disease cycle and epidemiology, diagnosis, and management. Includes links to web-based resources and references. Published by the UF Department of Plant Pathology, July 2007.

PP-233, a 10-page illustrated publication by Aaron J. Palmateer, Randy C. Ploetz, and Philip F. Harmon, is a section of the 2006 Plant Disease Management Guide. The authors describe several important diseases of avocado in Florida, their symptoms and causal organisms, disease cycle and epidemiology, and management. Includes a table of fungicides registered for use on avocado in Florida. Published October 2006.

PP-233, a 5-page fact sheet by Philip Harmon, Aaron Palmateer, and Rachel Ribbeck, provides information homeowners should know before using fungicide products to manage diseases in the home lawn and landscape. It describes what a disease is, the "disease triangle" explaining how diseases occur, diagnosis and prevention, and fungicide facts. Includes two tables, one listing fungicide products marketed toward homeowners, and one listing fungicide products marketed toward professional pesticide applicators. Published by the UF Department of Plant Pathology, September 2006. PP-233/PP154: Homeowner's Guide to Fungicides for Lawn and Landscape Disease Management (ufl.edu)

Southern wilt, caused by the bacterium Ralstonia solanacearum (Rs), is currently an important disease for geranium producers. Different races of R. solanacearum affect hundreds of plant species around the world. This document is PP 206, one of a series of the Plant Pathology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date February 2005. PP 206/PP131: Southern Wilt of Geranium (ufl.edu)

Pythium blight or cottony blight rapidly kills cool-season turfgrasses overseeded as winter cover of warm-season species. The disease can occur on bermudagrass in the summer, but disease severity on this warm-season species often is limited when compared to the damage caused to cool-season turfgrass. Pythium aphanidermatum as well as other species, such as P. torulosum, have been associated with Pythium blight of overseeded turfgrasses in Florida. This document is PP 203, one of a series of the Plant Pathology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date September 2004. PP 203/PP124: Pythium Blight on Overseeded Turfgrass (ufl.edu)

Information contained in this publication is intended to help blueberry growers in Florida identify and manage Botrytis blossom blight. For more information, search the EDIS website (http://edis.ifas.ufl.edu) or contact your local UF/IFAS Extension agent (http://ifas.ufl.edu/extension-offices-rec-maps.shtml). This document is PP198, one of a series of the Plant Pathology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date April 2004. PP198/PP119: Botrytis Blossom Blight of Southern Highbush Blueberry (ufl.edu)

Sudden oak death is a new disease capable of causing a range of symptoms from leaf spots to plant death on many woody hosts. Because sudden oak death is a new disease, much about the pathogen, host range, and the disease epidemiology is unknown. This document is PP197, one of a series of the Plant Pathology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date March 2004. PP197/PP118: Sudden Oak Death and Ramorum Blight (ufl.edu)