Lynn Maher at Harvest Time
Our research program is currently exploring several themes.
Secondary Metabolites, Flavor, and Consumer Quality Traits
We have devoted considerable effort over the years to work on secondary metabolites in carrot, onion, and table beet. We are continuing to pursue studies on volatiles that are associated with flavor, particularly geosmin, sucrose, and oxalic acid. Geosmin delivers the earthy flavor to certain plant foods and is also produced by Streptomyces bacteria that live largely in the soil. Initial investigations suggested the genotypic specificity of geosmin concentration in table beet and presence of geosmin even under sterile culture conditions would be difficult to explain if microbial populations were the sole cause of this trait. We believe that table beet is capable of endogenous production of geosmin, and Solveig Hanson has recently completed a study evaluating the stability of this trait across environments in Wisconsin. She has also documented a large QTL associated with this trait in table beet and examined the role of this compound in consumer preferences across a range of other variables. Adam D’Angelo has picked up this thread of research and is taking it in some new and interesting directions, and recently he has been joined by Audrey Pelikan, who will be taking over the project in late 2022. Audrey and Adam’s work is supported by USDA-Hatch.
Work on this aspect of our research in the last five years has resulted in a series of publications, including the following:
Hanson, S.J., Dawson, J.C., Goldman, I.L. 2022. Participatory plant breeding reveals that geosmin concentration is not the central determinant of hedonic liking in table beet. Euphytica. 281:14. https://link.springer.com/article/10.1007/s10681-021-02959-w
Hanson, S.J., Dawson, J.C., Goldman, I.L. 2021. Beta vulgaris ssp. vulgaris chromosome 8 shows significant association with geosmin concentration in table beet. G3. G3 Genes|Genomes|Genetics, jkab344, https://doi.org/10.1093/g3journal/jkab344
Hanson, S.J., and Goldman, I.L. 2019. Genotype Is Primarily Responsible for Variance in Table Beet Geosmin Concentration, but Complex Genotype × Environment Interactions Influence Variance in Total Dissolved Solids. J. Amer. Soc. Hort. Sci. 144:429-438. https://doi.org/10.21273/JASHS04758-19
Maher, L., and I.L. Goldman. 2018. Endogenous Production of Geosmin in Table Beet. HortScience. doi: 10.21273/HORTSCI12488-17 53: 67-72
Maher, L., and I.L. Goldman. 2017. Bi-Directional Recurrent Half Sib Family Selection for Geosmin Concentration in Table Beet (Beta vulgaris). Crop Science. 57:2564–2574. doi: 10.2135/cropsci2017.02.0111
Breeding for Resistance to Disease in Table Beet
Katharina Wigg worked on breeding table beet for resistance to Rhizoctonia solani, an important disease in this crop. Katharina has developed a greenhouse screening technique and backcrossed resistance into table beet germplasm. She identified resistance and susceptibility in plant introductions, cultivars, and breeding lines, and found two new QTLs associated with this trait in segregating populations. Her work was supported by the Midwest Food Product’s Association.
Emilee Gaulke, Liam Dixon, and Audrey Kruse are working on foliar diseases in table beet, primarily bacterial leaf spot and Cercospora. Their studies include controlled trials in greenhouse settings, trials across the state to examine field performance, and evaluation of the the crop during both vegetative and reproductive growth. A substantial portion of this work is directed at understanding the disease and its control in organic environments. Their work is supported by grants from the USDA-SCRI program, Wisconsin’s Specialty Crop Block Grant program, and the WISCORE program.
Publications in recent years on these projects include:
Gaulke, E., and Goldman, I.L. 2022. Screening Table Beet and Swiss Chard for Resistance to Pseudomonas syringae pathovar aptata. HortScience. In Press.
Wigg, K. et al. 2022. Novel QTL Associated with Rhizoctonia solani Kühn Resistance Identified in Two Table Beet x Sugar Beet F2:3 Populations Using a New Table Beet Reference Genome. Crop Science. In Press.
Wigg, K.S., and I.L. Goldman, 2020. Variability in Reaction to Root and Crown Rot Caused by Rhizoctonia Solani Among Table Beet Cultivars, Breeding Lines, and Plant Introductions in Controlled Environment Conditions. HortScience. 55:1482-94. https://doi.org/10.21273/HORTSCI15011-20
Genetic Control of Shape
A substantial effort in our lab has been to determine the genetic control of root shape in carrot. This was facilitated by the development of a digital imaging system by Scott Brainard, who recently completed his Ph.D working on this project. This effort has been picked up by Andrey Vega Alfaro and Madeline Oravec, who are mapping QTL associated with root traits in carrot and beet, respectively, as well as studying the effect of density on some of these parameters. Recent papers on this subject include:
Brainard, S.H., Bustamante, J.A., Dawson, J.C., Spalding, E.P., and Goldman, I.L. 2021. A digital image-based phenotyping platform for analyzing root shape attributes in carrot. Frontiers in Plant Science. https://doi.org/10.3389/fpls.2021.690031
Brainard, S.H., Ellison, S.L., Simon, P.W. et al. Genetic characterization of carrot root shape and size using genome-wide association analysis and genomic-estimated breeding values. Theor Appl Genet (2021). https://doi.org/10.1007/s00122-021-03988-8
Development of a Haploid Inducer in Carrot
Chandler Meyer, who is co-advised with Patrick Krysan, is developing a haploid inducer system in carrot through gene editing of CENH3. This creative approach involves the development of a protoplast transformation and regeneration system. Chandler’s work is supported by a grant from the USDA and the Gabelman-Seminis Wisconsin Distinguished Graduate Fellowship in Plant Breeding and Plant Genetics. A new publication on this subject has recently appeared:
Meyer CM, Goldman IL, Grzebelus E, Krysan PJ. Efficient production of transgene-free, gene-edited carrot plants via protoplast transformation. Plant Cell Rep. 2022 Apr;41(4):947-960. doi: 10.1007/s00299-022-02830-9. Epub 2022 Jan 28. PMID: 35089385.
General Breeding and Research
Our breeding work and our research programs are intertwined. We are selecting and evaluating in both conventional and organic environments. We have long-standing partnerships with farmers who have helped support our breeding activities, with the network of Agriculture Research Stations in the College of Agricultural and Life Sciences, and with scientists at seed companies. These partnerships are critical to the continuation of our breeding and research programs.
Our program is a member of the Vegetable Breeding Institute, a public-private partnership fostering interaction between public breeders and vegetable seed companies. For more information on the Vegetable Breeding Institute, follow this link. Our breeding programs, particularly graduate student support for plant breeding in organic systems, have also been supported by USDA, Seed Matters, Ceres Trust, and NC-SARE.
Some recent publications on breeding and genetics research in our crops include:
Goldman, I.L. 2022. Agronomy and production of edible Alliums. In: Edible Alliums: Modern Biology, Production and Uses. Botany, Production and Uses series. Rabinowitch, H.D. and Thomas, B. eds. CABI International. In press.
Goldman, I.L., and Janick, J. 2021.Evolution of Root Morphology in Table Beet: Historical and Iconographic. Frontiers in Plant Science. 12: doi: 10.3389/fpls.2021.689926
Cramer, C.S., Mandal S., SharmaS., Shahabedddin NourbakhshS. Goldman, I., and Guzman, I. 2021..Recent Advances in Onion Genetic Improvement. Agronomy. https://www.mdpi.com/2073-4395/11/3/482
Goldman, I.L. 2020. Celebrating the International Year of Plant Health. Crop Science. 13 October. https://doi.org/10.1002/csc2.20342
Dwivedi, S.L., Goldman, I.L., Ceccarelli, S., Ortiz, R., 2020. Advanced analytics, phenomics, and biotechnology approaches to enhance genetic gains in plant breeding. Advances in Agronomy. https://doi.org/10.1016/bs.agron.2020.02.002
Goldman, I.L. 2020. Root vegetables. In Physiology of Vegetable Crops, 2nd Edition, C. Wien, editor. CABI International.
Dwivedi, S., Goldman, I.L., Ortiz, R. 2019. Pursuing the Potential of Heirloom Cultivars to Improve Adaptation, Nutritional, and Culinary Features of Food Crops. Agronomy 9(8), 441; https://doi.org/10.3390/agronomy9080441