What does powdery mildew look like?. How to use the agar tubes to collect samples. Collecting Powdery Mildew from the Field. Aim to harvest a nice green leaf, ideally with a single pustule. Using tweezers, insert infected sample approximately 1-2cm into the agar slope. - PowerPoint PPT Presentation
Text of What does powdery mildew look like?
Collecting Powdery Mildew from the Field.Using tweezers, insert infected sample approximately 1-2cm into the agar slope.Screw cap tight for shippingAim to harvest a nice green leaf, ideally with a single pustule.
Murray and Brennan 2010Powdery 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 formationConidal germination and hyphal developmentConidal deposition onto susceptible hostCleistothecia production after occurrence of two hyphae of opposite mating typesCleistothecia release ascosporesColonies produce conidia that are dispersed by windBgh life cycle
Disease controlJayasena et. al. 2008Key: 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
In WA the disease is esp prominent resulting in ~33m of loss annuallyHas te potential to rise upto $72 million without proper controlBGH is and obligate biotroph which means it has the absolute requirment to obtain nutrients from a living host.The reproductive cycle of Bgh is polycyclic. dominated primarily by an asexual haploid form with a sexual diploid phase. While asexual reproduction is the quickest means of exponential population growth, sexual reproduction provides an added advantage through the conception of novel genotypes or pathotypes.
This is a very efficent and effective mechanism capable of producing numerous and genetically diverse progeny*