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Thesis (M.S.)—University of Nebraska—Lincoln, 1962. Department of Horticulture and Forestry.


Copyright 1962, the author. Used by permission.


The late blight fungus, Phytophthora. infestans(Mont.) de Bary, of potatoes has, through its intermittent destruction of this crop, forced men to move from the land of their nativity to areas of new hope. Its spectacular destruction led to the recognition that microorganisms could cause plant disease and subsequently to the development of the science of plant pathology. The fungus has been studied extensively since 1845. Yet, over a century later, the relationship between sporulation and spread of the fungus on different host phenotypes is still imperfectly known.

The present study was undertaken to investigate methods for counting sporangia samples, to determine the type of information that can be obtained from sporangia populations, and to relate the genetic response of seedling potatoes to P. infestans in terms of sporangia harvested from infected leaf areas.

Advisor: Dermot P. Coyne