Lab 6

Introduction
During this lab period, we were originally supposed to pick and count ascospores from our Neurospora crosses. However, because the perithecia had not shot as many ascospores as we needed, we settled for crushing perithecia to look at the immature ascospores inside. We also observed various mushrooms that were available at the front of the room.

Original Plan
As many of the Neurospora crosses possessed perithecia with beaks and ascospores which had been shot onto the lid of the plate, it was assumed that we would be able to pick and count the ascospores. However, upon closer inspection of the plates, it was found that the crosses had not matured to the point that was needed for our purposes. If they had been mature, sterile dissecting needles would have been used to pick out perithecia and mount onto glass slides. The perithecia would then be crushed in order to observe less mature ascospores than the ones that were shot. After this, we would have picked ascospores with a dissecting needle and transferred a single spore to an agar slant. The slant then would have been heat shocked. Heat shock is necessary to induce the production of ascospores, which explains why Neurospora serves as a primary colonizer after forest fires. Another way to induce the production of ascospores, according to Dr. Ebbole, is to place the slant in a dark place overnight, then expose it to light. This induces the production of ascospores.

Realized Plan
As mentioned above, we were not able to count ascospores during this lab period as the perithecia were not mature. However, perithecia were still crushed and observed under the scope. My Neurospora plates had definitely not matured to the point where I had many perithecia (Figs. 1-3), so I used one of Lorna's plates to find a perithecium (Fig 4). After crushing, I was able to see various stages of immature ascospores (Fig. 5). Dr. Shaw was able to take a photograph of the fluorescent nuclei in the spores on my slide (Fig. 6).

Fig. 1
My SMRP10xCSP-1 cross.

Fig. 2
My SMRP10xNCAL0 cross

Fig. 3
My SMRP10xSMRP11 cross

Fig. 4
Lorna's cross

Fig. 5
Various stages of ascospores that came out of a crushed perithcium.

Fig. 6
Fluorescent nuclei of ascospores from slide in Fig 5.

Observation of Basidiomycetes
There were many different mushrooms and morels available for viewing during this lab period. The stinkhorn fungus, Phallus spp., has a foul odor similar to carrion, which attracts some carrion-breeding insects (Fig. 7). These insects act to disperse the spores of this genus. The next fungus, Daedaleopsis confragosa, is a plant pathogen that causes white rot of many hardwood trees and conifers (Fig. 8). Chemical compounds derived from the Turkey Tail fungus, Coriolus versicolor (Trametes versicolor) (Fig. 9) are used in different remedies for cancer in China and Japan. The Bird's Nest Fungi, Cyathus olla, is a saprobe that relies on rainfall for dispersal (Figs. 10, 11). Another genus of fungi often referred to as Bird's Nest Fungi is Nidula spp (Fig. 12). One interesting fact about this fungus is that is produces a compound this a major ingredient in raspberry flavor. The next fungus observed was Xylaria spp, which is also known as Stag's Horn, Dead Man's Fingers and Dead Moll's Fingers (Fig. 13). This genus is comprised of wood and plant debris decomposers. The Common Morel, Morchella esculenta, is considered to be one of the most highly prized mushrooms as it is edible and delicious (Fig. 14). However, when eaten raw, these mushrooms can cause intestinal distress and may become poisonous over time. The Sulfur Shelf or Chicken of the Woods mushroom, Laetiporus sulphureus, is known to be a good substitute for poultry in many recipes, but can be poisonous if eaten raw (Fig. 15). The Lingzhi mushroom, Ganoderma lucidum, has been consumed for medicinal purposes in China for over 2,000 years (Figs. 16, 17). The Hemlock Varnish Shelf mushroom, Ganoderma tsugae, which is closely related to the Lingzhi mushroom, is also used for medicinal purposes (Fig. 18). Finally, many undetermined fungi were also available for viewing (Fig. 19).

Fig. 7
Stinkhorn fungus, Phallus spp.

Fig. 8
Daedaleopsis confragosa

Fig. 9
Turkey Tail fungus, Coriolus versicolor (Trametes versicolor)

Fig. 10
Bird's Nest Fungi, Cyathus olla

Fig. 11
Bird's Nest Fungi, Cyathus olla

Fig. 12
Another Bird's Nest Fungi, Nidula spp.

Fig 13.
Stag's Horn, Dead Man's Fingers, Dead Moll's Fingers (Xylaria spp.).

Fig. 14
The Common Morel, Morchella esculent a

Fig. 15
Sulfur Shelf or Chicken of the Woods fungus, Laetiporus sulphureus

Fig. 16
The Lingzhi mushroom, Ganoderma lucidum

Fig. 17
The Lingzhi mushroom, Ganoderma lucidum

Fig, 18
The Hemlock Varnish Shelf mushroom, Ganoderma tsugae

Fig. 19
Undetermined fungi

Conclusion
Picking and counting ascospores will continue next week when (hopefully) the Neurospora crosses will be more mature.

All for now.

C