International Research: Heterokaryosis in a Clonal Population of the Chestnut Blight Fungus

Cornell Univ - State: Awds Made Prior May 2010, Ithaca NY

Investigators

Abstract

This joint research project, headed by Michael Milgroom of Cornell University and his counterpart, Kiril Sotirovski of the Forestry Institute at Sts. Kiril and Metodij University in Skopje, will examine Cryphonectria parasitica, known as the chestnut blight fungus. Fingi have the capacity to maintain nuclei with distinctly different genetic material in the same individual; this phenomenon is called heterokaryosis. The chestnut blight fungus appears to be heterokaryotic in nature, but the mechanism for its origin is not yet known. Together, the researchers intend to explore the mechanisms responsible for heterokaryosis by studying it in clonal populations, i.e., those that are asexual and therefore lack recombination. Populations of C. parasitica in Macedonia are ideal for this because they have very low genetic diversity and are likely to be clonal. Therefore, the goals of this project are first to test whether populations are clonal, and second to screen for heterokaryons. The cooperative research plan calls for analyzing previous collections of C. parasitica from Macedonia and Greece, and collecting additional samples in Macedonia, while targeting specific populations for more in-depth study. The Macedonian research partner, Dr. Sotirovski, is an expert forest pathologist with extensive knowledge of chestnut trees and C. parasitica in Macedonia. His expertise is highly complementary to the principal investigator's background in fungal genetics. Both the researchers and their students will benefit from shared biological materials, technology and analytical tools. Chestnut blight, caused by C. parasitica, continues to be an economically significant disease across North America, Europe and Asia. Results are expected to improve our basic understanding of fungal genetics and provide new insight into the biology of forest diseases. Success may lead to improved methods for biological control of chestnut blight with fungal viruses. This project in plant population biology fulfills the program objective of advancing scientific knowledge by enabling experts in the United States and South Central Europe to combine complementary talents and share research resources in areas of strong mutual interest and competence. Broader impacts include the introduction of two U.S. students to the international community of mycologists through research at the Macedonian institution and direct involvement in the project's field studies of natural populations.