Mounting media

If glass distilled water is used, add 1 ml of 1% ZnSO4 and 0.5% CuSO4. Heat the full chemical solution without sucrose in a water bath for 15 min. After cooling add sucrose and agar. Melt the agar and autoclave. Do not filter (Dhingra and Sinclair 1985).

Heat 20 g malt extract in 1 L of water until dissolved, then add 20 g agar and heat until the agar melts (Dhingra and Sinclair 1985).

Polyvinyl alcohol-lactic acid-glycerol (PVLG) is used to prepare permanent slides with unbroken and crushed fungal specimens, as well as with fragments of mycorrhizal roots. Its viscosity enables to manipulate the position of the specimen examined and, hence, accurately determine their properties. To stabilize the mounted specimens, slides have to dry for ca. 2 weeks at a room temperature or at 65oC for 12-24 h. The latter procedure is recommended, because it clears the contents of the specimens and their surroundings from oil droplets and air bubbles. Such permanently mounted specimens remain unchanged even after 20 years of their storage.

Polyvinyl alcohol-lactic acid-glycerol consists of the ingredients listed below:

Melzer's reagent

Melzer's reagent shows dextrinoid reactions of components of the fungal structures examined. In freshly extracted fungal structures, intensity of the staining reaction mainly depends on the length of carbohydrate chains present in the components. In stored specimens, the reactivity of the structures usually decreases or completely disappears.

Melzer's reagent consists of the following ingredients:

Ingredient	Quantity
Chloral hydrate	100 g
Distilled water	100 ml
Iodine	1.5 g
Potassium iodine	5.0 g

Melzer's reagent may be used alone or as a mixture with PVLG. However, specimens mounted in a pure Melzer's reagent quickly dry out even when a coverslip is sealed and, thereby, usually are unsuitable for further studies. A mixture of Melzer's reagent and PVLG in a volume ratio of 1:1 enables to prepare permanent slides of advantages similar to those with PVLG alone. The mixture should be stored in a dark bottle.

Trypan blue

Ingredient	Quantity
Lactic acid	100 ml
Trypan blue	1 g

Trypan blue may be replaced with other stains, e. g., with aniline blue.

REFERENCES

Dhingra O. D., Sinclair J. B. 1985. Basic plant pathology methods. CRS Press, Inc. Boca raton, Florida.

Ingredient	Quantity (g)
NaNO3	2.00
K2HPO4	1.00
MgSO4 7H2O	0.50
KCl	0.50
FeSO4	0.01
Sucrose	30.00
Agar	20.00
Distilled water	1 L

Ingredient	Quantity (g)
Malt extract	20.00
Agar	20.00
Distilled water	1 L

Ingredient	Quantity (g)
Potato peptone	4.00
Glucose	20.00
Agar	15.00
Distilled water	1 L

Ingredient	Quantity (g)
Peptone, Difco	10.00
Glusoce	40.00
Bacto-Yeast Extract	3.00
Agar	15.00
Distilled water	1 L