Collecting Powdery Mildew from the Field.

Using tweezers, insert infected sample approximately 1-2cm into the agar slope.

Screw cap tight for shipping

Aim to harvest a nice green leaf, ideally with a single pustule.

Murray and Brennan 2010

Powdery mildew

• Causal agent Blumeria graminis f.sp. hordei (Bgh)• Especially prominent in Southern WA• $33M yield loss per annum

Millions of dollars loss annually

Mycelium and conidiophore

formation

Conidal germination and

hyphal development

Conidal deposition onto susceptible host Cleistothecia production

after occurrence of two hyphae of opposite

mating types

Cleistothecia release ascospores

Colonies produce conidia that are

dispersed by wind

Sexual Cycle

AsexualCycle

Bgh life cycle

Disease control

Jayasena et. al. 2008

Key: 1= very effective, 2=moderately effective, 3= not effective

Agronomic characteristics of malting and feed barley varieties when grown in Western Australia

Disease resistance/ susceptibillity profiles of malting and feed barley varieties when grown in Western Australia