Date of Graduation

Spring 2023


Master of Science in Agriculture


College of Agriculture

Committee Chair

Chin-Feng Hwang


The improvement of Eastern black walnut (Juglans nigra L.) cultivars could increase market expansion. Improved cultivars with superior qualities would increase profitability for both the seller and the buyer. Agronomically and economically important traits such as heavier nut weight, disease resistance, tree structure integrity, and yearly nut production can be efficiently improved by breeding black walnuts via marker-assisted selection. Microsatellite/simple sequence repeat markers were used in this research to determine potential intraspecific hybrids between ‘Football’ and ‘Sparrow’ cultivars. Intraspecific is defined as of the same genus and species. This quality makes it more difficult to identify hybrids because the parent plants DNA have similar base pair sizes. The two main goals for this research are to identify hybrid plants for the expansion of an existing mapping population and to optimize annealing temperatures of publicly available primer sets for the identification of additional polymorphic markers between ‘Football’ and ‘Sparrow’. Of the 1,015 progeny plants tested, sixty-one were determined to be intraspecific hybrids. Those sixty-one new genotypes were added to the F1 mapping population to a total of 237 plants at the Missouri State Fruit Experiment Station, Mountain Grove, MO 65711. Two hundred and eighty markers were tested for polymorphism and fifty-seven were detected as polymorphic for ‘Football’ and ‘Sparrow’ and kept for further assessment in future research.


marker-assisted selection, microsatellite, simple sequence repeat, black walnut, intraspecific, polymorphic

Subject Categories

Genetics | Plant Breeding and Genetics


© Makenna B. Thompson

Open Access