Fungi

Andrew Loyd, Jason A. Smith, Brantlee S. Richter, Robert A. Blanchette, Matthew E. Smith, andJason A. Smith

Ganoderma Karst. is a large and diverse genus of wood decay fungi that can rot the roots and/or lower trunk of many tree species. There are several laccate (varnished or polished) Ganoderma species that are found in the southeastern United States. These species can be recognized by their shiny, reddish-brown, and shelf-like fruiting bodies. These fruiting bodies have a pale pore surface on the bottom that darkens with age or handling and can be stipitate (stem present) or sessile (stem absent). Laccate Ganoderma species fruit year-round in most parts of the southeastern United States, but fruiting may be restricted to warm months in northern areas. When Ganoderma fruiting bodies are observed, it is an indication that wood decay is active, whether on fallen logs, buried roots, or the trunks of living or dead trees.

Yin-Tse Huang and Jiri Hulcr

Demian F. Gomez and Jiri Hulcr

Hui-Ling Liao

A UF/IFAS numbered peer reviewed Fact Sheet. Published by Plant Systems

C. Benton Willis, Michael Goodnight, Jessica Velte, Marin T. Brewer, andMatthew E. Smith

Exobasidium fungi are plant pathogens that primarily infect plants in the Ericaceae family, including blueberries and azaleas. Their infections cause plant cells to proliferate (hyperplasia) and expand (hypertrophy). The fungi then use the increased surface area to produce spores. These changes manifest as symptoms on the host plant, varying by species of Exobasidium. The range of symptoms includes leaf and fruit spots, blisters, shoot proliferation (witches' broom), and galls. Infected plant tissues can also become swollen and distorted, as well as chlorotic (yellow) or discolored (reddish to pink). As this infected tissue matures, the surface becomes white and powdery from fungal spore production. Exobasidium fungi tend to cause symptoms on the plant during ideal weather conditions but can likely survive on the leaf surface or other available substrates year-round. Disease management includes chemical applications and cultural practices before the spores have the chance to mature.

Hui-Ling (Sunny) Liao, Ko-Hsuan Chen, Florencia Marcon, Robert (Robbie) Jones, Brittany Justesen, Joseph Walter, Ann Blount, Cheryl Mackowiak, Doug Mayo, and Marcelo Wallau

The beef cattle ranchers in Florida reported some health issues related to cattle grazing on warm-season grass pastures, such as bahiagrass and bermudagrass. The illness was not attributable to nutritional imbalances, or other possible causes. The focus then turned to what the animals were consuming, and forages were implicated. In general, the forages in Florida are just fine, however, sometimes under certain circumstances the fungi that live in our forages may produce “secondary metabolites”. All the forage harbor fungi. Some fungi are good in that they aid our forages to grow better, helping to mine nutrients from the soil or atmosphere. Sometimes they are not so good, like when high levels of ergotized seed occur in the seed heads of bahiagrass.

Holly Andres, Kaile Zhang, Kaile Zhang, andHui-Ling Liao

Ectomycorrhizal fungi (EMF) form symbiotic relationships with approximately 60% of trees and woody plants among temperate and boreal forests. EMF also serve as the primary symbionts in subtropical and tropical forests, particularly in conifer forests, including those in Florida's climate. These fungi influence the global carbon, nitrogen, and phosphorus cycles, sequestering or supplying these elements as necessary for ecosystem processes and resilience. However, EMF are susceptible to environmental stressors and management practices, including fertilizers, fungicides, and mechanical disturbances. This publication aims to provide general knowledge to the general public on the biology and ecological functions of EMF in natural and managed forest ecosystems. By understanding the role and benefits of EMF in these environments, forest managers, tree nursery operators, and timber industry stakeholders can gain valuable insights for incorporating EMF into their management practices.

Elena Karlsen-Ayala, Romina Gazis, and Matthew E. Smith

Mushrooms growing in potting soil are a common problem reported in nursery production and in potted plants in the indoor and outdoor home landscape. Many of these fungi are saprotrophic and feed on the organic matter contained in the potting soil itself and/or in the mulch, which varies in composition but often contains tree bark, wood chips, pine straw, moss, or leaves. These fungi are not necessarily harmful to the plants, but fungal fruiting bodies can make plants unmarketable. Unknown fungi can also be concerning to retailers and homeowners because of potential toxicity to pets and children. The purpose of this publication is to provide homeowners and retail nursery growers with an overview of some of the most common mushroom-forming fungi found in potted plants and potting soils in Florida. We also provide cultural control recommendations to help prevent or reduce mushroom growth.

Holly Andres, Hui-Ling Liao, Kaile Zhang, andKaile Zhang

Arbuscular mycorrhizal fungi, as symbionts to host plants, play a pivotal role in regulating plant nutrient uptake and maintaining soil health. As approximately 80%-90% of terrestrial plants are colonized by mycorrhizal fungi, this fungal group significantly contributes to the overall yield and functions in crop production. This publication provides updated general knowledge on the biology and ecological functions of the most common types of mycorrhizal fungi. These fungi are highly sensitive to environmental stressors and management practices, such as the application of phosphorus and nitrogen fertilizers, as well as fungicides. An enhanced understanding of mycorrhizal fungi can raise awareness among growers, prompting them to consider mycorrhizal fungal activities when managing their farms. Moreover, it can improve the general public's knowledge of the role mycorrhizal fungi play in natural terrestrial ecosystems, including agricultural and forest ecosystems.