The University of Wisconsin carrot breeding and genetics program: 69 cycles of breeding for improved quality, productivity, and accessibility in processing carrot

The University of Wisconsin breeding program has been geared toward the development of disease resistant, high carotene, high quality processing carrot inbred lines and populations for use in the commercial seed industry since 1949. One of the primary activities in the breeding program was the development of inbred lines that could be used by commercial breeders in hybrid combinations to produce two and three way F1 hybrids. These inbred lines have been released from the program since the 1960s and constitute a pool of publicly available germplasm for use in the development of processing carrot cultivars. With nearly 70 cycles of carrot breeding completed, the goal of this paper is to present some of the research highlights from the last 25 years, with a focus on recent work including development of our understanding of carotenoid and tocopherol content and evolution, germplasm organization and accessibility, the genetic control of market class, and gene editing approaches to improve carrot.