Lab 1 20120905

1. Tips for using microscope
Keep in mind that whenever we should transport the microscope gently with 2 hands holding it and use the body to support it too.

2. Mounts type:
Squash mounts: Add a drop of water on the glasses. Use sterilized scapel to cut a small piece of agar with colonies on it. Put a cover slide and then squash the agar gently. It is easier to observe the spores since the outside force push the fungi release spores.
Tape mounts: when we want to see the intact fungal structure, like sporophore, it is better to use tape mount by just using the tape contact with the hyphal structure on the plate gently. Then, put the piece of tape on the glass slide with a drop a water on it. By using tape mounts, you can save the intact structue but we have to handle it really gently.

Other ways:
We can even put the agar directly on the slides.
We can also use the innoculating needle to pick a small amount of colonies and suspend in the water, then cover with cover slide, but do not let the cover slide sit on the colonies directly by putting small pieces of glasses on the glass to support the cover slide in order to leave some space for the fungi and keep the intact structure.

3. Have a general review of fungal world
3.1 Alternaria brassicicola

 Pic 1 Aspergillus conidia chain

Pic 2 Aspergillus conidia

3.2 Cladospsorium Sp. 

Pic 3 Cladospsorium Sp. (Upper: squash mount, Lower: tape mount)

With squash mount, I can see the hyphal fragment.
With the tape mount, I can see the intact structure of Cladospsorium Sp. conidiaphore.

Pic 4 Cladospsorium Sp. conidiaphore

3.3 Thielaviopsis bassiola 
Thielaviopsis bassiola has 2 types of asexual spores: phialospore (endospores) and aleuriospore(chlamydospores). Chlamydospores are produced in chains (two to eight spores per chain). The dark, thick walled chlamydospores separate at maturity and each cell is capable of germination.
Endoconidia are produced in greater numbers than the chlamydospores. These spores are variable in size with slightly rounded ends. The septae hyphae are hyaline at first and become pigmented with age.  A sexual state has not been observed with T. basicola. 

Pic 5 Thkelaviopsis bassicola conidiaphore

3.4 Pythium ultimum (oomycete)

 Pic 6 Pythium ultimum

Pic 7 Oogonium (female)

The oogonium after fertilization will turn into oospore (thick wall)

4. Hemocytometer
We can first dilute the spore suspension to a certain concentration and then use trypan blue to stain the fungi and then count on Hemocytometer under microscope.