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Using Ustilago maydis as a Trojan Horse for In Situ Delivery of Maize Proteins
Published on: February 8, 2019
Inbreeding levels of two Ustilago maydis populations
Charles W Barnes1, Les J Szabo, Georgiana May
1USDA-ARS Cereal Disease Laboratory, 1551 Lindig Street, St. Paul, Minnesota 55108-6052.
Abstract:
Little is known about the population mating behavior of the smut fungus Ustilago maydis DC (Corda). To determine the amount of inbreeding that occurs in local U. maydis populations, two cornfields were sampled, one in North America (NA) at Le Sueur, Minnesota, and one in South America (SA) at Tarariras, Uruguay. These fields were chosen because of their geographic isolation and host management differences. Inbreeding coefficients (F(is)) were calculated using data derived from amplified fragment length polymorphism (AFLP) markers. Mean F(is) values estimated for both the NA (-0.08), and the SA (-0.02) populations statistically are not different from zero. The results of this study demonstrate that the U. maydis population structure in both cornfields results predominately from out-crossing and suggests that teliospores infrequently act as single infection units. The genetic differentiation between populations was high (F(st) = 0.25).
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