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BPP Grad Student Selected to Speak at APS Grad Symposium

The focus of this year's symposium is New Contributions to Epidemiology and Plant Health. Sierra's research concerns powdery mildew of hop (causal agent Podosphaera macularis), which can cause severe or complete crop loss if left unmanaged.  In the Pacific Northwest the fungus is not known to reproduce sexually despite doing so in other areas of the world. In powdery mildews sexual reproduction is controlled by the MAT locus. There are two idiomorphs of the MAT locus and both are required for P. macularis to reproduce sexually. Sierra discovered the MAT idiomorphs in P. macularis and developed a simple PCR assay to determine mating type, which was used to characterize the frequency of idiomorphs in the pathogen population. The results indicate that only one mating type is present in the Pacific Northwest, which provides an explanation for the absence of the ascigerious stage. The introduction of the second mating type and thus the sexual stage could change the way powdery mildew and hops are currently managed in the Pacific Northwest. Sierra's thesis research has lead to new quarantine rules to prevent the introduction of the second mating type into the region. She has also conducted studies to characterize the development of cleistothecia.

cleistothecium of hop powdery mildewcleistothecium of hop powdery mildew

This opportunity is an honor for the students selected.  Sierra will receive a travel award to the Symposium that will take place 9-13 August, 2014 in Minneapolis, MN and will be held jointly with the Canadian Phytophathological Society.

For more details regarding the I.E. Melhus Graduate Student Symposium