PARP

Purpose

For selective isolation of Phytophthora ramorum and other Phytophthora (hymexazol-sensitive species) and Pythium spp.

Ingredients

Main Recipe

Ingredient	1 L	500 mL
Corn Meal Agar (Accumedia)	17 g	8.5 g
Ampicillin	0.25 g	0.125 g
Rifampicin solution	1 mL	0.5 mL
Pimaricin solution	0.4 mL	0.2 mL
PCNB	5 mL	2.5 mL

Stock Solutions

Ingredient	1 mL
DMSO	1 mL
Rifampicin	0.01 g
Dissolve 0.01 g rifampicin in 1.0 mL DMSO

Ingredient	1 mL
Distilled water	1 mL
Pimaricin	25 mg
Dissolve Pimaricin in distilled water; 2.5% aq. sol

Ingredient	400 mL
95% ethanol	400 mL
PCNB	2 g
Carefully dissolve 2 g PCNB into heated ethanol. Heat 400 mL of 95% ethanol to 65-70°C by placing a beaker of water on a burner and then put ethanol flask in water bath

Instructions

1. To make up the Penta-Chloro-Nitro-Benzene (PCNB): Carefully dissolve 2g of PCNB crystals in 400mL heated 95% ethanol. Heat the ethanol by placing a beaker of water on a burner and then the flask of EtOH in the water bath.
2. Mix Cornmeal agar in DI water
3. Autoclave and cool to 50-55°C
4. Add the rest of the ingredients, mix well and pour into petri dishes under low light conditions

Notes

• Some of these ingredients are carcinogenic and hazardous.
• Use caution when making this medium.
• Also, the antibiotics in PARP are light sensitive.
• Plates should be poured under low-light conditions and stored in the dark.
• Store plates in the dark for up to 1 month.

References

• Snover-Clift, K., McKeller, M., and Chen,. 2008. Standard Operating Procedure for Plant Diagnostic Laboratories: Sudden Oak Death/Ramorum Blight, Phytophthora ramorum. Version 1.1. NPDN

Contributed by

From the University of Florida Plant Disease Clinic-GNV mediabook: contributed by Anne Vitoreli.