FFF Exam 1
What are the differences between asci/ascospores and basidia/basidiospores? Which of the two do the following groups have; mushrooms, boletes, bracket fungi, cup fungi, fungi with flask-shaped sexual reproductive structures?
- Ascospores and basidiospores are 2 types of sexual spores produced by fungi. - Ascospores: produced by fungi ascomycetes and produced inside asci. > Develop endogenously (arising within the organism or cell) > flask-shaped sexual reproductive structure - Basidiospores are specific to basidiomycetes and are produced in basidia > Develop exogenously (arising from a source outside the organism or cell) > mushrooms, boletes, cup fungi, bracket fungi
What difference is there in the spores produced by sexual or asexual reproduction?
- Asexual (spores produced by extension and cleavage of specialized hyphal cells) - Sexual (spores produced after fusion of hyphae of two compatible mating types)
Who were some of the early mycologists? What were their major accomplishments?
- Christian Hendrik Persoon >First person to begin describing lots of fungi - Elias Fries (1794-1878) >Has named thousands and thousands of fungi > Named the fungi similar to Linnaeus > His major work includes three huge volumes of Systemma Mycologicum that named fungi - Lewis David de Schweinitz (1780-1834) > North American Father of Mycology > Famous for naming and describing wood rot fungi - Beatrix Potter (1866-1943) > Mycologist > Drew hundreds of illustrations of fungi which are used today to identify/describe fungi - George Washington Carver (1864-1943) > Developed a lot of products from peanuts > Improved quality of soil > First African American student at Iowa University > First person to work on and described plant pathogenic fungi
What are the characteristics of fungi?
- Eukaryotes - Composed of cells with nucleus or nuclei - Unique cell walls (made of chitin & composed of glucans) - no chlorophyll (heterotrophs and external digestion and absorptive nutrition) - simple morphology - Reproduction by way of spores
What are the rules for naming fungi?
- For each species, there is only one valid name - The name must be in Latin and in print or electronic form (first description of a new fungus must be in English and in printed or electronic form) - Earliest published description has priority - For fungi, the official starting date is 1753 - "Type" specimen and culture must be designated - First citation in literature must include the author's name or abbreviated name
Who is Anton de Bary?
- He is known as the founder of mycology and researched roles of fungi and other agents causing plant diseases - discovered the cause of the Irish potato famine
Why were epidemics of late blight so bad during the times of the Irish Potato Famine? What contributed to the disease being so catastrophic?
- Ireland has a cool and wet environment perfect for the late blight disease. - In 1845 hot and dry weather dramatically changed and became cool and rainy for the following 19 years in Europe - Throughout Europe potato crops failed, but was worse in Ireland because Irish peasants depended on the potato for their food
Which groups have been recently discovered to be fungi?
- Microsporidia - Cyrptomycota
What would lead to a name change of a fungus?
- Sexual stage discovered - Older name discovered has priority - fungus originally misidentified - fungus reclassified based on genetic code - similar species are consolidated - a conglomerate is divided into a new species
What are some characteristics of wind-dispersed spores?
- Small - Lightweight - Dry - Abundantly produced - Long-lived have dark, thick cell walls - Short-lived may be colorless with thin cell walls
What is Prototaxites? Where has it been found? What characteristics does it have that has led researchers to think it is a fungus?
- Weird and huge - thought to be a conifer plant but eventually recognized as a fungus because it was determined to be a heterotroph - they had pores, clamp connections, and septa like other fungi - found in Norther Hemisphere; Saudi Arabia to Canada
What are the main dispersal mechanisms for fungi? Which is the most common?
- Wind (most common) - Rain - Animals -Self- propelled
What causes late blight of potato? What type of organism is it? What are some of its characteristics? Where did it originate?
- caused by Phytophthora ingestans - it is a fungus-like oomycete pathogen - appears as water soaked spots and in moist and cool conditions spots grow - on leaf underside, spore- producing zone of white moldy growth appears - tissues is water- soaked, reddish brown - disease gets worse under wet and cold conditions only dry warm weather can help slow or stop growth - originated in Central Mexico and introduced to US and caused epidemic in US in early 1840s
What stimulates spore production?
- change in day length (light) - less food - change in moisture status
What is Bordeaux mixture? How was it discovered?
- combination of copper sulfate, lime, and water- is an effective fungicide and bactericide that has been used to control diseases of fruit and nut trees, vine fruits, and ornamental plants - discovered accidentally in 1882, by botany professor Pierre-Marie-Alexis Millardet
Fungi simple morphology?
- no circulatory or vascular system - made up of tubular cells called hyphae ( excrete digestive enzymes and absorb substrates/ digestive materials) - Reproduction by spores (can be sexual and asexual)
What conditions do fungi prefer for growth and what stimulates reproduction/spore production?
- subdued sunlight, because intense UV light is toxic to many fungi - Temp. for active growth above 0 C (32 F) and below 32 C (90 F) - pH between 6 and 8 - High humidity, some free water but not so much that the environment is starved for oxygen -EXCEPTIONS TO ALL OF THESE
What is causing the bananapocalypse? What is the disease and causal fungus? Why are bananas so susceptible? What is being done to make sure bananas do not go extinct?
- victims of a fungal pathogen known as Panama Disease (fusarium oxysporum f. sp. cubense) - in 1990s, a new race of Fusarium wilt: TR4 - investigation on how to transfer resistance genes from other crops to bananas - replacing susceptible cultivars with resistant ones
What are some characteristics of oomycetes?
- walls of cellulose - Swimming spores with 2 different kinds of flagella
External digestion?
-Digest on the outside and absorb it back in (absorptive nutrition) - Enzymes that they have determine the substrate that they live on (limits where fungi live)
What are the three wine grape diseases discussed? What are the causal organisms? Where did the pests/pathogens originate and where were they introduced? Are European grapevines or North American grapevines more susceptible to these diseases? Why?
...
Which are the closest relatives of fungi?
Animals are most closely related to fungi
What is a ballistospore? How does it work?
Ballistospore in fungi is a spore forcibly propelled from its site. The basidiospores of the mushrooms, produced on the gills and on the walls of the spores, are ballistospores. They are shot a very short distance from the vertical walls of the fruiting structure and then drift down. In other fungi, including certain slime molds, they are propelled in other directions by various mechanisms and are sometimes projected a considerable distance from the fruiting structure.
What are bioluminescent fungi? What is the compound that makes them fluoresce? What are some theories as to why they fluoresce?
Bioluminescent fungi are those that have a glow-in-the-dark effect. Luciferin is reduced by an enzyme and then oxidized to release energy in form of light. Bioluminescence theories: - spore dispersal and increased survival - lure animals to spread spores - scare predators away
What are the three diseases of cacao that we discussed? Which organisms and types of organisms cause them? How are these diseases controlled?
Black pod disease: - caused by oomycete - protective sprays of copper containing fungicides in combo with systemic fungicides Cocoa swollen shoot virus: - caused by virus - infected trees are removed and destroyed to prevent further spread and gap between plantations Frosty pod: - caused by fungus - planting ocoa varieties produce pods during the dry season allows pod to avoid the disease, and any pods showing disease should be removed to prevent spread as well as application of copper containing fungicides
What is the unique mechanism that inky caps use to disperse their spores in the wind?
Liquify the gills from the bottom up as the spores mature the cap then peels away and allows spore to be at the best position to catch wind. (autodigestion)
How many fungi have been described? What percent of all fungi does this likely represent?
Out of 1 to 1.5 million fungi estimated to inhabit our planet, approx. 10% have been described.
What are wood blewits? What is their preferred substrate and what time of year are they commonly found? How can you distinguish them from deadly Violet Cortinarius?
The mushroom likes very cold weather and sometime fruits in great abundance, especially in duff or wood chips. Cortinarius can be distinguished because they have a rusty brown spore print and blewits have tan to bluff spore prints.
Which groups are no longer considered fungi?
Water and Slime molds
Why is sexual reproduction of the late blight organism problematic? Why did the disease reemerge in the 1990's?
When the virus sexually reproduces it needs both mating types A1 and A2 and produces a oospores, which can survive in the soil for up to 10 years without a host. - Sexual reproduction changes the epidemiology and increases the adaptability of the pathogen, and thus changes the way in which disease control is approached - In the early 1990s, exotic strains strains from Mexico were aggressive and resistant to fungicide and these strains caused severe epidemics in US and Canada.
What is the dispersal mechanism for the following groups of fungi: rusts, powdery mildews, puffballs, bird's nest fungi, fungi that ooze out spores from a flask like a tube of toothepaste, aeroaquatic fungi, fungi with tetraradiate spores, stinkhorns, flower mimics, fusiform rust nectar, truffles and false truffles, Pilobolus, zoospores?
Wind - Powdery Mildew - Puffballs - Rusts Rainsplash - Bird's nest fungi - fungi that ooze out spores Surface Water - Aeroaquatic fungi -fungi with tetaradite spore Animals - truffles and false truffles - stinkhorn - fusiform rust - flower mimics Self- Propelled - Pilobolus - zoospores
What type of organism causes most plant diseases?
fugal or fungal - like organisms
