Abortion of infection structures of wheat leaf rust in susceptible and partially resistant wheat genotypes

Summary Arrest of the growth of wheat leaf rust infection structures was studied with fluorescence microscopy in seedling leaves and flag leaves of the susceptible spring wheat genotypes Morocco and Kaspar and the partially resistant genotypes Westphal 12A and Akabozu. The percentages non-penetrants and substomatal vesicle abortion were low in all genotypes. In the partially resistant genotypes the percentage abortion of infection structures was higher than in the susceptible genotype Morocco. Aborted infection structures had formed one or two haustorial mother cells. In adult plants differences in the percentage aborted infection structures between susceptible and partially resistant genotypes were more pronounced than in seedlings. The so-called late abortion was not observed.