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Ivan Simko
Crop Improvement and Protection Research
Research Geneticist (Plants)

Phone: (831) 755-2862
Fax: (831) 755-2814

(Employee information on this page comes from the REE Directory. Please contact your front office staff to update the REE Directory.)

Projects
Genetic Improvement of Lettuce, Spinach, Celery, Melon, and Related Species
In-House Appropriated (D)
  Accession Number: 444159
Improving Lettuce Cultivars against Bacterial Leaf Spot (BLS) through Breeding, Genetics, and Study of the BLS-Lettuce Interaction
Reimbursable Cooperative Agreement (R)
  Accession Number: 439349
Assessing the Effect of Exogenous Silicon Application on Yield and Quality of Lettuce Produce
Reimbursable Cooperative Agreement (R)
  Accession Number: 442348
Metabolomics Approach to Identify Biomarkers for Lettuce Resistance to Diseases, Pests, and Physiological Disorders, and Postharvest Quality
Trust Fund Cooperative Agreement (T)
  Accession Number: 446161
Lettuce Breeding and Genetics (2021)
Trust Fund Cooperative Agreement (T)
  Accession Number: 440199
Lettuce Breeding, Genetics, and Physiology
Trust Fund Cooperative Agreement (T)
  Accession Number: 442154

Publications (Clicking on the reprint icon Reprint Icon will take you to the publication reprint.)
Leveraging observations of untrained panelists to screen for quality of fresh-cut romaine lettuce - (Peer Reviewed Journal)
Host cell wall composition and localized microenvironment implicated in resistance to basal stem degradation by lettuce drop (Sclerotinia minor) Reprint Icon - (Peer Reviewed Journal)
Simko, I., Mamo, B.E., Foster, C.E., Adhikari, N.D., Subbarao, K.V. 2024. Host cell wall composition and localized microenvironment implicated in resistance to basal stem degradation by lettuce drop (Sclerotinia minor). BMC Plant Biology. 24. Article 717. https://doi.org/10.1186/s12870-024-05399-5.
In search of optimum fresh-cut raw material: Using computer vision systems as a sensory screening tool for browning resistant romaine lettuce accessions Reprint Icon - (Peer Reviewed Journal)
Bornhorst, E.R., Luo, Y., Park, E., Zhou, B., Turner, E.R., Teng, Z., Simko, I., Fonseca, J.M., Trouth, F.J. 2024. In search of optimum fresh-cut raw material: Using computer vision systems as a sensory screening tool for browning resistant romaine lettuce accessions. Horticulturae. 10(7). Article e10070731. https://doi.org/10.3390/horticulturae10070731.
Assessing contents of sugars, vitamins, and nutrients in baby leaf lettuce from hyperspectral data with machine learning models Reprint Icon - (Peer Reviewed Journal)
Eshkabilov, S., Simko, I. 2024. Assessing contents of sugars, vitamins, and nutrients in baby leaf lettuce from hyperspectral data with machine learning models. Agriculture. 14(6). Article 834. https://doi.org/10.3390/agriculture14060834.
Distribution of three Verticillium dahliae races in coastal California and evaluation of resistance in lettuce Reprint Icon - (Peer Reviewed Journal)
Mandal, M.K., Koike, S.T., Tsuchida, C., Stanghellini, H., Guerrero, J., Sandoya, G., Klosterman, S.J., Simko, I., Subbarao, K.V. 2024. Distribution of three Verticillium dahliae races in coastal California and evaluation of resistance in lettuce. Plant Disease. 108(7):2170-2180. https://doi.org/10.1094/PDIS-01-24-0193-RE.
Identification and characterization of lettuce cultivars with high inhibitory activity against the human pathogen Escherichia coli O157:H7: Toward a plant-intrinsic hurdle approach to microbial safety Reprint Icon - (Peer Reviewed Journal)
George, A.S., Simko, I., Brandl, M. 2024. Identification and characterization of lettuce cultivars with high inhibitory activity against the human pathogen Escherichia coli O157:H7: Toward a plant-intrinsic hurdle approach to microbial safety. Postharvest Biology and Technology. 211. Article 112816. https://doi.org/10.1016/j.postharvbio.2024.112816.
Proanthocyanidins: Key for resistance to Globisporangium (formerly Pythium) seed rot of pea Reprint Icon - (Peer Reviewed Journal)
Ewing, E.E., Weeden, N.F., Simko, I. 2024. Proanthocyanidins: Key for resistance to Globisporangium (formerly Pythium) seed rot of pea. Journal of the American Society for Horticultural Science. 149(1):37-49. https://doi.org/10.21273/JASHS05340-23.
Phenotypic characterization, plant growth and development, genome methylation, and mineral elements composition of neotetraploid lettuce (Lactuca sativa L.) Reprint Icon - (Peer Reviewed Journal)
Simko, I., Zhao, R.B. 2023. Phenotypic characterization, plant growth and development, genome methylation, and mineral elements composition of neotetraploid lettuce (Lactuca sativa L.). Frontiers in Plant Science. 14. Article 1296660. https://doi.org/10.3389/fpls.2023.1296660.
Development and validation of a mid-density DArTag-based genotyping platform for lettuce (Lactuca sativa) - (Abstract Only)
Ling, M., Sapkota, M., Tang, X., Eriksen, R.L., Mou, B., Richardson, K.L., Simko, I., Beil, C., Sheehan, M. 2024. Development and validation of a mid-density DArTag-based genotyping platform for lettuce (Lactuca sativa). Plant and Animal Genome Conference, January 16, 2024, San Diego, California.
Phytochemical and agronomic characterization of high-flavonoid lettuce lines grown under field conditions Reprint Icon - (Peer Reviewed Journal)
Cho, E., Gurdon, C., Zhao, R.B., Peng, H., Pouley, A., Raskin, I., Simko, I. 2023. Phytochemical and agronomic characterization of high-flavonoid lettuce lines grown under field conditions. Plants. 12(19). Article 3467. https://doi.org/10.3390/plants12193467.
Breeding lettuce for resistance against Sclerotinia minor Reprint Icon - (Peer Reviewed Journal)
Simko, I., Subbarao, K.V., Hayes, R.J. 2023. Breeding lettuce for resistance against Sclerotinia minor. HortScience. 58(12):1526–1532. https://doi.org/10.21273/HORTSCI17399-23.
Genome-wide association mapping reveals loci for enzymatic discoloration on cut lettuce Reprint Icon - (Peer Reviewed Journal)
Peng, H., Luo, Y., Teng, Z., Zhou, B., Pearlstein, D.J., Wang, D., Turner, E.R., Nou, X., Wang, T.T., Tao, Y., Fonseca, J.M., Simko, I. 2024. Genome-wide association mapping reveals loci for enzymatic discoloration on cut lettuce. Postharvest Biology and Technology. 207. Article 112577. https://doi.org/10.1016/j.postharvbio.2023.112577.
Differentially methylated genomic regions of lettuce seeds relate to divergence across morphologically distinct horticultural types Reprint Icon - (Peer Reviewed Journal)
Simko, I. 2023. Differentially methylated genomic regions of lettuce seeds relate to divergence across morphologically distinct horticultural types. AoB Plants. 15(5). Article plad060. https://doi.org/10.1093/aobpla/plad060.
Concentration and retention of ascorbic acid, carotenoids, and sugars in fresh-cut lettuce in modified atmospheric packaging Reprint Icon - (Peer Reviewed Journal)
Sthapit Kandel, J., Simko, I., Hayes, R.J., Mou, B. 2024. Concentration and retention of ascorbic acid, carotenoids, and sugars in fresh-cut lettuce in modified atmospheric packaging. Horticultural Plant Journal. https://doi.org/10.1016/j.hpj.2023.07.008.
Dataset on the single nucleotide variation in diversity panel of 500 lettuce accessions genotyped with tunable genotyping-by-sequencing (tGBS) method Reprint Icon - (Peer Reviewed Journal)
Simko, I. 2023. Dataset on the single nucleotide variation in diversity panel of 500 lettuce accessions genotyped with tunable genotyping-by-sequencing (tGBS) method. Data in Brief. 49. Article 109419. https://doi.org/10.1016/j.dib.2023.109419.
Genetic determinants of lettuce resistance to drop caused by Sclerotinia minor identified through genome-wide association mapping frequently co-locate with loci regulating anthocyanin content Reprint Icon - (Peer Reviewed Journal)
Simko, I., Sthapit Kandel, J., Peng, H., Zhao, R.B., Subbarao, K.V. 2023. Genetic determinants of lettuce resistance to drop caused by Sclerotinia minor identified through genome-wide association mapping frequently co-locate with loci regulating anthocyanin content. Theoretical and Applied Genetics. 136. Article 180. https://doi.org/10.1007/s00122-023-04421-y.
Genetic and physiological determinants of lettuce partial resistance to Impatiens necrotic spot virus Reprint Icon - (Peer Reviewed Journal)
Simko, I., Hasegawa, D.K., Peng, H., Zhao, R.B. 2023. Genetic and physiological determinants of lettuce partial resistance to Impatiens necrotic spot virus. Frontiers in Plant Science. 14. Article 1163683. https://doi.org/10.3389/fpls.2023.1163683.
Extending lettuce shelf life through integrated technologies Reprint Icon - (Peer Reviewed Journal)
Peng, H., Simko, I. 2023. Extending lettuce shelf life through integrated technologies. Current Opinion in Biotechnology. 81. Article 102951. https://doi.org/10.1016/j.copbio.2023.102951.
Weather factors, soil microbiome, and bacteria-fungi interactions as drivers of the epiphytic phyllosphere communities of romaine lettuce Reprint Icon - (Peer Reviewed Journal)
Brandl, M., Mammel, M., Simko, I., Richter, T., Gebru, S., Leonard, S. 2023. Weather factors, soil microbiome, and bacteria-fungi interactions as drivers of the epiphytic phyllosphere communities of romaine lettuce. Food Microbiology. 113. Article 104260. https://doi.org/10.1016/j.fm.2023.104260.
Improving the post-harvest quality and shelf-life of lettuce with molecular breeding - (Abstract Only)
Taylor, G., Lingga, N., Damerum, A., Simko, I., Michelmore, R., Milner, S. 2023. Improving the post-harvest quality and shelf-life of lettuce with molecular breeding. Plant and Animal Genome Conference, January 13-18, 2023, San Diego, California.
We are the champions. The index for evaluating concentration of championships using a sliding window approach Reprint Icon - (Peer Reviewed Journal)
Simko, I. 2022. We are the champions. The index for evaluating concentration of championships using a sliding window approach. Heliyon. 8(12). Article e12025. https://doi.org/10.1016/j.heliyon.2022.e12025.
Lettuce breeding, genetics, and physiology - (Abstract Only)
Simko, I. 2022. Lettuce breeding, genetics, and physiology. California Leafy Greens Research Program Mid-Year Meeting, October 20, 2022, Salinas, California.
Phenotypic and genetic analyses of yellow spot malady in lettuce Reprint Icon - (Peer Reviewed Journal)
Peng, H., Zhao, R.B., Smith, R., Simko, I. 2022. Phenotypic and genetic analyses of yellow spot malady in lettuce. Scientia Horticulturae. 305. Article 111389. https://doi.org/10.1016/j.scienta.2022.111389.
Insights into nitrogen metabolism in the wild and cultivated lettuce as revealed by transcriptome and weighted gene co-expression network analysis Reprint Icon - (Peer Reviewed Journal)
Kumar, P., Eriksen, R.L., Simko, I., Shi, A., Mou, B. 2022. Insights into nitrogen metabolism in the wild and cultivated lettuce as revealed by transcriptome and weighted gene co-expression network analysis. Scientific Reports. 12. Article 9852. https://doi.org/10.1038/s41598-022-13954-z.
Lettuce (Lactuca sativa L.) germplasm resistant to bacterial leaf spot caused by race 1 of Xanthomonas hortorum pv. vitians (Brown 1918) Moriniére et al. 2020 Reprint Icon - (Peer Reviewed Journal)
Sandoya, G.V., Rosenthal, E., Simko, I., Rodrigues-Porto, L.N., Wadlington, W.H., Bull, C.T., Carroll, A. 2022. Lettuce (Lactuca sativa L.) germplasm resistant to bacterial leaf spot caused by race 1 of Xanthomonas hortorum pv. vitians (Brown 1918) Moriniére et al. 2020. Journal of Plant Pathology. 104:993–1008. https://doi.org/10.1007/s42161-022-01123-0.
Genome-wide association mapping reveals genomic regions frequently associated with lettuce field resistance to downy mildew Reprint Icon - (Peer Reviewed Journal)
Simko, I., Peng, H., Sthapit Kandel, J., Zhao, R.B. 2022. Genome-wide association mapping reveals genomic regions frequently associated with lettuce field resistance to downy mildew. Theoretical and Applied Genetics. 135:2009–2024. https://doi.org/10.1007/s00122-022-04090-3.
Phenotypic characters and inheritance of Yellow Spot malady in lettuce - (Abstract Only)
Peng, H., Zhao, R.B., Smith, R., Simko, I. 2022. Phenotypic characters and inheritance of Yellow Spot malady in lettuce. American Society for Horticultural Science Annual Meeting, July 30-August 3, 2022, Chicago, Illinois.
Identification of quantitative trait loci associated with bacterial leaf spot resistance in baby leaf lettuce Reprint Icon - (Peer Reviewed Journal)
Sthapit Kandel, J., Sandoya, G.V., Zhou, W., Read, Q.D., Mou, B., Simko, I. 2022. Identification of quantitative trait loci associated with bacterial leaf spot resistance in baby leaf lettuce. Plant Disease. 106(10):2583-2590. https://doi.org/10.1094/PDIS-09-21-2087-RE.
Mapping quantitative trait loci for lettuce resistance to Verticillium dahliae race 3, plant development, and leaf color using an ultra-high-density bin map constructed from F2 progeny Reprint Icon - (Peer Reviewed Journal)
Simko, I., Puri, K.D., Dhar, N., Peng, H., Subbarao, K.V. 2022. Mapping quantitative trait loci for lettuce resistance to Verticillium dahliae race 3, plant development, and leaf color using an ultra-high-density bin map constructed from F2 progeny. Phytofrontiers. 2(3):257-267. https://doi.org/10.1094/PHYTOFR-11-21-0078-R.
Seasonality, shelf life and storage atmosphere are main drivers of the microbiome and E. coli O157:H7 colonization of post-harvest lettuce cultivated in a major production area in California Reprint Icon - (Peer Reviewed Journal)
Leonard, S., Simko, I., Mammel, M., Richter, T., Brandl, M. 2021. Seasonality, shelf life and storage atmosphere are main drivers of the microbiome and E. coli O157:H7 colonization of post-harvest lettuce cultivated in a major production area in California. Environmental Microbiome. 16. Article 25. https://doi.org/10.1186/s40793-021-00393-y.
Lettuce breeding and genetics (USDA) - (Other)
Richardson, K.L., Simko, I., Mou, B. 2021. Lettuce breeding and genetics (USDA). California Leafy Greens Research Program Mid-Year Meeting, October 13, 2021 (virtual).
Hypersensitivity to triforine in lettuce is triggered by a TNL gene through the disease resistance pathway Reprint Icon - (Peer Reviewed Journal)
An, G., Simko, I., Chen, J., Yu, C., Lavelle, D., Zhang, W., Michelmore, R., Kuang, H. 2021. Hypersensitivity to triforine in lettuce is triggered by a TNL gene through the disease resistance pathway. Plant Biotechnology Journal. 19(11):2144-2146. https://doi.org/10.1111/pbi.13679.
Phenotypic characterization and inheritance of browning on cut surfaces of stems and leaf ribs of romaine lettuce Reprint Icon - (Peer Reviewed Journal)
Peng, H., Luo, Y., Teng, Z., Zhou, B., Bornhorst, E.R., Fonseca, J.M., Simko, I. 2021. Phenotypic characterization and inheritance of enzymatic browning on cut surfaces of stems and leaf ribs of romaine lettuce. Postharvest Biology and Technology. 181. Article 111653. https://doi.org/10.1016/j.postharvbio.2021.111653.
Mapping and identification of genetic loci affecting earliness of bolting and flowering in lettuce Reprint Icon - (Peer Reviewed Journal)
Rosental, L., Still, D.W., You, Y., Hayes, R.J., Simko, I. 2021. Mapping and identification of genetic loci affecting earliness of bolting and flowering in lettuce. Theoretical and Applied Genetics. 134:3319-3337. https://doi.org/10.1007/s00122-021-03898-9.
Identification of marker compounds for predicting browning of fresh-cut lettuce using untargeted UHPLC-HRMS metabolomics Reprint Icon - (Peer Reviewed Journal)
Liu, Z., Sun, J., Teng, Z., Luo, Y., Yu, L., Simko, I., Chen, P. 2021. Identification of marker compounds for predicting browning of fresh-cut lettuce using untargeted UHPLC-HRMS metabolomics. Postharvest Biology and Technology. 180.Article 111626. https://doi.org/10.1016/j.postharvbio.2021.111626.
Genomics and marker assisted improvement of vegetable crops Reprint Icon - (Peer Reviewed Journal)
Simko, I., Jia, M., Venkatesh, J., Kang, B., Weng, Y., Barcaccia, G., Lanteri, S., Bhattarai, G., Foolad, M.R. 2021. Genomics and marker-assisted improvement of vegetable crops. Critical Reviews in Plant Sciences. 40(4):303-365. https://doi.org/10.1080/07352689.2021.1941605.
Dynamics of Verticillium dahliae race 1 population under managed agricultural ecosystems Reprint Icon - (Peer Reviewed Journal)
Chen, J., Zhang, D., Huang, J., Li, R., Wang, D., Song, J., Puri, K.D., Lin, Y., Kong, Z., Tong, B., Li, J., Huang, Y., Simko, I., Klosterman, S.J., Dai, X., Subbarao, K.V. 2021. Dynamics of Verticillium dahliae race 1 population under managed agricultural ecosystems. BMC Biology. 19. Article 131. https://doi.org/10.1186/s12915-021-01061-w.
Resistance to lettuce drop (Sclerotinia spp.): cell wall composition analysis to determine biological basis - (Abstract Only)
Mamo, B., Foster, C.E., Adhikari, N., Simko, I. 2021. Resistance to lettuce drop (Sclerotinia spp.): cell wall composition analysis to determine biological basis. American Phytopathological Society Annual Meeting, August 2-6, 2021 (virtual).
Phenotypic and genetic characterization of stem and rib browning in romaine lettuce - (Abstract Only)
Peng, H., Luo, Y., Teng, Z., Zhou, B., Bornhorst, E.R., Fonseca, J.M., Simko, I. 2021. Phenotypic and genetic characterization of stem and rib browning in romaine lettuce. American Society for Horticultural Science Annual Conference, August 5-9, 2021, Denver, Colorado.
Lettuce breeding and genetics - (Other)
Simko, I., Mou, B., Richardson, K.L., Mccreight, J.D. 2021. Lettuce breeding and genetics. California Leafy Greens Research Program Annual Meeting, March 30, 2021 (virtual).
Elucidating the biological basis of resistance to lettuce drop through cell wall composition analysis - (Other)
Mamo, B.E., Foster, C.E., Adhikari, N.D., Hayes, R.J., Simko, I. 2021. Elucidating the biological basis of resistance to lettuce drop through cell wall composition analysis. Postdoctoral Research Symposium, March 30, 2021, Davis, California (virtual).
Transcriptomic and gene co-expression network analysis of cultivated lettuce (Lactuca sativa L) and its wild progenitor (L. serriola) under contrasting nitrogen conditions - (Abstract Only)
Kumar, P., Eriksen, R.L., Simko, I., Mou, B. 2021. Transcriptomic and gene co-expression network analysis of cultivated lettuce (Lactuca sativa L) and its wild progenitor (L. serriola) under contrasting nitrogen conditions. American Society for Horticultural Science Annual Conference, August 5-9, 2021, Denver, Colorado.
Epidemiological characterization of lettuce drop (Sclerotinia spp.) and biophysical features of the host identify soft stem as a susceptibility factor Reprint Icon - (Peer Reviewed Journal)
Mamo, B., Eriksen, R.L., Adhikari, N.D., Hayes, R.J., Mou, B., Simko, I. 2021. Epidemiological characterization of lettuce drop (Sclerotinia spp.) and biophysical features of the host identify soft stem as a susceptibility factor. Phytofrontiers. 1(3):182-204. https://doi.org/10.1094/PHYTOFR-12-20-0040-R.
Molecular mapping of water-stress responsive genomic loci in lettuce (Lactuca spp.) using kinetics chlorophyll fluorescence, hyperspectral imaging and machine learning Reprint Icon - (Peer Reviewed Journal)
Kumar, P., Eriksen, R.L., Simko, I., Mou, B. 2021. Molecular mapping of water-stress responsive genomic loci in lettuce (Lactuca spp.) using kinetics chlorophyll fluorescence, hyperspectral imaging and machine learning. Frontiers in Genetics. 12. Article 634554. https://doi.org/10.3389/fgene.2021.634554.
IdeTo: Spreadsheets for calculation and analysis of area under the disease progress over time data Reprint Icon - (Peer Reviewed Journal)
Simko, I. 2021. IdeTo: Spreadsheets for calculation and analysis of area under the disease progress over time data. Phytofrontiers. 1(3):244-247. https://doi.org/10.1094/PHYTOFR-11-20-0033-A.
Identification of major quantitative trait loci controlling field resistance to downy mildew in cultivated lettuce (Lactuca sativa) Reprint Icon - (Peer Reviewed Journal)
Parra, L., Simko, I., Michelmore, R.W. 2021. Identification of major quantitative trait loci controlling field resistance to downy mildew in cultivated lettuce (Lactuca sativa). Phytopathology. 111(3):541-547. https://doi.org/10.1094/PHYTO-08-20-0367-R.
Genetics of partial resistance against Verticillium dahliae race 2 in wild and cultivated lettuce Reprint Icon - (Peer Reviewed Journal)
Sandoya, G.V., Truco, M.J., Bertier, L.D., Subbarao, K.V., Simko, I., Hayes, R.J., Michelmore, R.W. 2021. Genetics of partial resistance against Verticillium dahliae race 2 in wild and cultivated lettuce. Phytopathology. 111(5):842-849. https://doi.org/10.1094/PHYTO-09-20-0396-R.
Genetics of robustness under nitrogen- and water-deficient conditions in field-grown lettuce Reprint Icon - (Peer Reviewed Journal)
Macias-Gonzalez, M., Truco, M.J., Smith, R., Cahn, M.D., Simko, I., Hayes, R.J., Michelmore, R.W. 2021. Genetics of robustness under nitrogen- and water-deficient conditions in field-grown lettuce. Crop Science. 61(3):1582-1619. https://doi.org/10.1002/csc2.20380.
Lettuce breeding - (Other)
Richardson, K.L., McCreight, J.D., Mou, B., Simko, I. 2020. Lettuce breeding. California Leafy Greens Research Program Mid-Year Meeting, October 6, 2020 (virtual).
Identification of factors affecting the deterioration rate of fresh-cut lettuce in modified atmosphere packaging Reprint Icon - (Peer Reviewed Journal)
Peng, H., Sthapit Kandel, J., Michelmore, R.W., Simko, I. 2020. Identification of factors affecting the deterioration rate of fresh-cut lettuce in modified atmosphere packaging. Food and Bioprocess Technology. 13:1997–2011. https://doi.org/10.1007/s11947-020-02538-2.
Clustering of soil sample microbiomes using metagenomic shotgun sequencing data - (Abstract Only)
Mammel, M., Leonard, S.R., Richter, T., Simko, I., Brandl, M. 2020. Clustering of soil sample microbiomes using metagenomic shotgun sequencing data. FDA Foods Program Regulatory Science Conference, September 1, 2020, College Park, Maryland.
Content of chlorophylls and anthocyanins in leaves and their relationship to color and conceptual midpoint quasi-color (database) Reprint Icon - (Database / Dataset)
Simko, I. 2020. Content of chlorophylls and anthocyanins in leaves and their relationship to color and conceptual midpoint quasi-color (database). TRY: Plant Trait Database. https://doi.org/10.17871/TRY.66.
Predictive modeling of a leaf conceptual midpoint quasi-color (CMQ) using an artificial neural network Reprint Icon - (Peer Reviewed Journal)
Simko, I. 2020. Predictive modeling of a leaf conceptual midpoint quasi-color (CMQ) using an artificial neural network. Sensors. 20(14):3938. https://doi.org/10.3390/s20143938.
Genome sequence of Verticillium dahliae race 1 isolate VdLs.16 from lettuce Reprint Icon - (Peer Reviewed Journal)
Chen, J.-Y., Zhang, D.-D., Huang, J.-Q., Wang, D., Hao, S.-J., Li, R., Puri, K.D., Yang, L., Tong, B.-Z., Xiong, K.-X., Simko, I., Klosterman, S.J., Subbarao, K.V., Dai, X.-F. 2020. Genome sequence of Verticillium dahliae race 1 isolate VdLs.16 from lettuce. Molecular Plant-Microbe Interactions. 33(11):1265-1269. https://doi.org/10.1094/MPMI-04-20-0103-A.
Resistance to bacterial leaf spot in baby leaf lettuce - (Abstract Only)
Sthapit Kandel, J., Sandoya, G.V., Mou, B., Simko, I. 2020. Resistance to bacterial leaf spot in baby leaf lettuce. American Society of Horticulture Science Annual Conference, August 9-13, 2020, Orlando, Florida.
Insight into deterioration of fresh-cut lettuce in modified atmosphere packaging - (Abstract Only)
Peng, H., Lavelle, D., Truco, M.-J., Michelmore, R., Simko, I. 2020. Insight into deterioration of fresh-cut lettuce in modified atmosphere packaging. American Society for Horticultural Science Annual Conference, August 9-13, 2020, Orlando, Florida.
Genome-wide association mapping reveals loci for shelf life and developmental rate of lettuce Reprint Icon - (Peer Reviewed Journal)
Sthapit Kandel, J., Peng, H., Hayes, R.J., Mou, B., Simko, I. 2020. Genome-wide association mapping reveals loci for shelf life and developmental rate of lettuce. Theoretical and Applied Genetics. 133:1947–1966. https://doi.org/10.1007/s00122-020-03568-2.
Genetic variation in response to N, P, or K deprivation in baby leaf lettuce Reprint Icon - (Peer Reviewed Journal)
Simko, I. 2020. Genetic variation in response to N, P, or K deprivation in baby leaf lettuce. Horticulturae. 6(1):15. https://doi.org/10.3390/horticulturae6010015.
Genetics of extended storage life - (Other)
Simko, I., Sthapit Kandel, J., Peng, H., Hayes, R.J., Truco, M.J., Michelmore, R.W. 2020. Genetics of extended storage life. Future of Lettuce Conference, March 16, 2020, Pismo Beach, California.
Factors, physiology, and genetics associated with the deterioration of fresh-cut lettuce in modified atmospheres - (Other)
Peng, H., Lavelle, D., Truco, M., Michelmore, R., Simko, I. 2020. Factors, physiology, and genetics associated with the deterioration of fresh-cut lettuce in modified atmospheres. Future of Lettuce Conference, March 16, 2020, Pismo Beach, California.
Genetic diversity, linkage disequilibrium and genome-wide association studies in lettuce - (Abstract Only)
Sthapit Kandel, J., Mou, B., Simko, I., Hayes, R.J. 2020. Genetic diversity, linkage disequilibrium and genome-wide association studies in lettuce. Plant and Animal Genome Conference, January 11-15, 2020, San Diego, California.
Phenomic and physiological analysis of salinity effects on lettuce Reprint Icon - (Peer Reviewed Journal)
Adhikari, N.D., Simko, I., Mou, B. 2019. Phenomic and physiological analysis of salinity effects on lettuce. Sensors. 19(21):4814. https://doi.org/10.3390/s19214814.
Genetic analysis of resistance to bacterial leaf spot in the heirloom lettuce cultivar Reine des Glaces Reprint Icon - (Peer Reviewed Journal)
Sandoya, G.V., Maisonneuve, B., Truco, M.J., Bull, C.T., Simko, I., Trent, M., Hayes, R.J., Michelmore, R.W. 2019. Genetic analysis of resistance to bacterial leaf spot in the heirloom lettuce cultivar Reine des Glaces. Molecular Breeding. 39:160. https://doi.org/10.1007/s11032-019-1072-6.
Lettuce and spinach breeding - (Other)
Simko, I., McCreight, J.D., Mou, B., Richardson, K.L. 2019. Lettuce and spinach breeding. California Leafy Greens Research Program Mid-Year Meeting, October 8, 2019, Salinas, California.
Genetic variation and relationship among content of vitamins, pigments, and sugars in baby leaf lettuce Reprint Icon - (Peer Reviewed Journal)
Simko, I. 2019. Genetic variation and relationship among content of vitamins, pigments, and sugars in baby leaf lettuce. Food Science and Nutrition. 7(10):3317–3326. https://doi.org/10.1002/fsn3.1196.
The LsVe1L allele provides a molecular marker for resistance to Verticillium dahliae race 1 in lettuce Reprint Icon - (Peer Reviewed Journal)
Inderbitzin, P., Christopoulou, M., Lavelle, D., Reyes-Chin-Wo, S., Michelmore, R.W., Subbarao, K.V., Simko, I. 2019. The LsVe1L allele provides a molecular marker for resistance to Verticillium dahliae race 1 in lettuce. Biomed Central (BMC) Plant Biology. 19:305. https://doi.org/10.1186/s12870-019-1905-9.
Identification of romaine lettuce (Lactuca sativa var. longifolia) varieties with reduced browning discoloration for fresh-cut processing Reprint Icon - (Peer Reviewed Journal)
Luo, Y., Bornhorst, E., Teng, Z., Zhou, B., Park, E., Turner, E.R., Simko, I. 2019. Identification of romaine lettuce (Lactuca sativa var. longifolia) varieties with reduced browning discoloration for fresh-cut processing. Postharvest Biology and Technology. 156:110931. https://doi.org/10.1016/j.postharvbio.2019.110931.
Identifying QTL for the control of flowering time under multiple environments in lettuce - (Abstract Only)
Rosental, L., You, Y., Hayes, R.J., Still, D., Simko, I. 2019. Identifying QTL for the control of flowering time under multiple environments in lettuce. Israeli Society of Field and Vegetable Crops Conference, May 27, 2019, Rehovot, Israel.
The genetics of resistance to lettuce drop (Sclerotinia spp.) in lettuce in a recombinant inbred line population from Batavia Reine des Glaces x Eruption Reprint Icon - (Peer Reviewed Journal)
Mamo, B.E., Hayes, R.J., Truco, M., Puri, K.D., Michelmore, R.W., Subbarao, K.V., Simko, I. 2019. The genetics of resistance to lettuce drop (Sclerotinia spp.) in lettuce in a recombinant inbred line population from Batavia Reine des Glaces x Eruption. Theoretical and Applied Genetics. 132(8):2439-2460. https://doi.org/10.1007/s00122-019-03365-6.
Genetic architecture of tipburn resistance in lettuce Reprint Icon - (Peer Reviewed Journal)
Macias Gonzalez, M., Truco, M.J., Bertier, L., Jenni, S., Simko, I., Hayes, R.J., Michelmore, R.W. 2019. Genetic architecture of tipburn resistance in lettuce. Theoretical and Applied Genetics. 132(8):2209–2222. https://doi.org/10.1007/s00122-019-03349-6.
Trends in lettuce and spinach production in the United States - (Abstract Only)
Simko, I., Mou, B., Richardson, K.L., McCreight, J.D. 2019. Trends in lettuce and spinach production in the United States. EUCARPIA Leafy Vegetables International Conference, June 24-28, 2019, Olomouc, Czech Republic.
Lettuce genetics of lettuce drop and Verticillium wilt resistance - (Abstract Only)
Mamo, B., Hayes, R.J., Simko, I., Subbarao, K.V. 2019. Lettuce genetics of lettuce drop and Verticillium wilt resistance. Soilborne Plant Pathogens Conference, March 26-28, 2019, San Marino, CA.
Variation in nutrient contents and retention in fresh-cut lettuce - (Abstract Only)
Sthapit Kandel, J., Mou, B., Simko, I., Hayes, R.J. 2019. Variation in nutrient contents and retention in fresh-cut lettuce. American Society for Horticultural Science Annual Conference, July 21-25, 2019, Las Vegas, Nevada.
Marker-assisted selection in lettuce breeding - (Abstract Only)
Simko, I. 2019. Marker-assisted selection in lettuce breeding. EUCARPIA Leafy Vegetables International Conference, June 24-28, 2019, Olomouc, Czech Republic.
Phenolics composition in lettuce upon ultraviolet radiation and temperature effects - (Abstract Only)
Sytar, O., Zivcak, M., Brestic, M., Rauh, C., Simko, I. 2019. Phenolics composition in lettuce upon ultraviolet radiation and temperature effects. Alps-Adria Scientific Workshop, April 1-6, 2019, Rimini, Italy.
Lettuce and Spinach Breeding - (Other)
Simko, I., Mou, B., McCreight, J.D., Richardson, K.L. 2019. Lettuce and Spinach Breeding. California Leafy Greens Research Program Meeting, March 19, 2019, Pismo Beach, CA.
Understanding salt tolerance in lettuce - (Abstract Only)
Adhikari, N.D., Soria, A., Simko, I., Mou, B. 2019. Understanding salt tolerance in lettuce. American Society of Horticultural Science Annual Meeting, July 21-25, 2019, Las Vegas, NV.
Understanding deterioration of fresh-cut lettuce in modified atmosphere packaging - (Abstract Only)
Peng, H., Lavelle, D., Truco, M.J., Zhao, R.B., Michelmore, R., Simko, I. 2019. Understanding deterioration of fresh-cut lettuce in modified atmosphere packaging. American Society for Horticultural Science Annual Conference, July 21-25, 2019, Las Vegas, Nevada.
Identifying QTL for the control of flowering time under multiple environments in lettuce - (Other)
Rosental, L., You, Y., Hayes, R.J., Still, D., Simko, I. 2019. Identifying QTL for the control of flowering time under multiple environments in lettuce. Israeli Society of Plant Sciences Conference, February 13, 2019, Sede Boqer, Israel.
Lettuce breeding and genetics. Resistance to diseases, improved quality, molecular markers - (Other)
Simko, I. 2018. Lettuce breeding and genetics. Resistance to diseases, improved quality, molecular markers. Plant Breeding Retreat, December 17-18, 2018, Monterey, CA.
Shift in accumulation of flavonoids and phenolic acids in lettuce attributable to changes in ultraviolet radiation and temperature Reprint Icon - (Peer Reviewed Journal)
Sytar, O., Zivcak, M., Bruckova, K., Brestic, M., Olsovska, K., Hemmerich, I., Rauh, C., Simko, I. 2018. Shift in accumulation of flavonoids and phenolic acids in lettuce attributable to changes in ultraviolet radiation and temperature. Scientia Horticulturae. 239:193–204. https://doi.org/10.1016/j.scienta.2018.05.020.
Understanding salt tolerance in lettuce - (Abstract Only)
Adhikari, N.D., Whitten, D., Soria, A., Simko, I., Mou, B. 2018. Understanding salt tolerance in lettuce. American Society of Horticultural Science Annual Meeting, July 31-August 3, 2018, Washington, DC.
Accuracy, reliability, and timing of visual evaluations of decay in fresh-cut lettuce Reprint Icon - (Peer Reviewed Journal)
Simko, I., Hayes, R.J. 2018. Accuracy, reliability, and timing of visual evaluations of decay in fresh-cut lettuce. PLoS One. 13(4):e0194635. https://doi.org/10.1371/journal.pone.0194635.
Lettuce and spinach breeding - (Other)
Simko, I., Mou, B., McCreight, J.D. 2018. Lettuce and spinach breeding. California Leafy Greens Research Program Annual Meeting, March 27, 2018, Pismo Beach, California.
Genome-wide association mapping of loci for the rate of deterioration in fresh-cut lettuce - (Abstract Only)
Sthapit, J., Mou, B., Hayes, R.J., Simko, I. 2018. Genome-wide association mapping of loci for the rate of deterioration in fresh-cut lettuce. American Society of Plant Biologists Annual Meeting, July 14-18, 2018, Montreal, Canada.
Genome-wide association mapping of deterioration in fresh-cut lettuce - (Abstract Only)
Sthapit, J., Mou, B., Simko, I., Hayes, R.J. 2018. Genome-wide association mapping of deterioration in fresh-cut lettuce. American Society of Horticultural Science Annual Meeting, July 31-August 3, 2018, Washington, DC.
Novel sources of resistance to Florida isolates of Bacterial leaf spot in lettuce (Lactuca sativa L.) - (Abstract Only)
Sandoya, G.V., Wadlington, W., Raid, R.N., Simko, I., Bull, C.T. 2018. Novel sources of resistance to Florida isolates of Bacterial leaf spot in lettuce (Lactuca sativa L.). American Society of Horticultural Science Annual Meeting, July 31-August 3, 2018, Washington, DC.
LsGA2ox2 regulates lettuce seed germination under darkness - (Abstract Only)
Huo, H., Niroula, M., Hill, T., Li, J., Nguyen, C., Truco, M.J., Simko, I., Michelmore, R.W., Bradford, K. 2018. LsGA2ox2 regulates lettuce seed germination under darkness. American Society of Horticultural Science Annual Meeting, July 31-August 3, 2018, Washington, DC.
Molecular markers reliably predict post-harvest decay of fresh-cut lettuce in modified atmosphere packaging Reprint Icon - (Peer Reviewed Journal)
Simko, I., Hayes, R.J., Truco, M., Michelmore, R.W., Antonise, R., Massoudi, M. 2018. Molecular markers reliably predict post-harvest decay of fresh-cut lettuce in modified atmosphere packaging. Horticulture Research. 5:21. https://doi.org/10.1038/s41438-018-0022-5.
PCR assay for Verticillium dahliae race 1 resistance in lettuce based on genome sequencing of 61 accessions - (Abstract Only)
Inderbitzin, P., Reyes-Chin Wo, S., Christopoulou, M., Michelmore, R.W., Subbarao, K.V., Simko, I. 2018. PCR assay for Verticillium dahliae race 1 resistance in lettuce based on genome sequencing of 61 accessions. International Congress of Plant Pathology, July 29-August 3, 2018, Boston, Massachusetts.
Characterization of resistance to lettuce drop, and its association with plant architecture and composition in lettuce - (Abstract Only)
Mamo, B.E., Adhikari, N.D., Foster, C., Zucker, L., Hayes, R.J., Subbarao, K.V., Simko, I. 2018. Characterization of resistance to lettuce drop, and its association with plant architecture and composition in lettuce. International Congress of Plant Pathology, July 29-August 3, 2018, Boston, Massachusetts.
Release of three iceberg lettuce populations that combined resistance to two soil borne diseases Reprint Icon - (Peer Reviewed Journal)
Hayes, R.J., Sandoya, G., Mou, B., Simko, I., Subbarao, K.V. 2018. Release of three iceberg lettuce populations that combined resistance to two soil borne diseases. HortScience. 53(2):247-250. https://doi.org/10.21273/HORTSCI12559-17.
Post-harvest decay in fresh-cut lettuce - (Other)
Simko, I. 2017. Post-harvest decay in fresh-cut lettuce. NIFA-SCRI Annual Project Meeting of Principle Investigators. October 20, 2017, Davis, California.
Lettuce and spinach breeding - (Other)
Simko, I., McCreight, J.D., Mou, B. 2017. Lettuce and spinach breeding. California Leafy Greens Research Program Annual Meeting. October 10, 2017, Salinas, California.
Variation within lactuca spp. for resistance to impatiens necrotic spot virus Reprint Icon - (Peer Reviewed Journal)
Simko, I., Richardson, C.E., Wintermantel, W.M. 2018. Variation within lactuca spp. for resistance to impatiens necrotic spot virus. Plant Disease. 102(2):341-348. https://doi.org/10.1094/PDIS-06-17-0790-RE.
Finding the fighters. Maturity-adjusted resistance of potato cultivars to Verticillium wilt Reprint Icon - (Trade Journal)
Simko, I., Haynes, K.G. 2017. Finding the fighters. Maturity-adjusted resistance of potato cultivars to Verticillium wilt. Potato Grower. 46:38-39.
Breeding and genetics of lettuce for resistance against race 2 Verticillium wilt - (Abstract Only)
Sandoya, G.V., Truco, M.J., Subbarao, K.V., Martin, F.N., Michelmore, R.M., Hayes, R.J., Simko, I. 2017. Breeding and genetics of lettuce for resistance against race 2 Verticillium wilt. National Association of Plant Breeders Annual Meeting, August 7-10, 2017, Davis, California.
Lettuce breeding - (Other)
Simko, I., Mou, B., McCreight, J.D. 2017. Lettuce breeding. California Leafy Greens Research Board. Available: http://calgreens.org/wp-content/uploads/2016/06/Lettuce-Breeding-USDA-ARS-Simko-Mou-and-McCreight.pdf.
Genome-wide association study for lettuce cultivars with improved salad processing efficiency - (Abstract Only)
Sthapit, J.K., Mou, B., Simko, I., Hayes, R.J. 2017. Genome-wide association study for lettuce cultivars with improved salad processing efficiency. American Society for Horticultural Science Annual Meeting, September 19-22, 2017, Waikoloa, Hawaii.
Characterization of Verticillium dahliae disease reactions in lettuce differential cultivars - (Abstract Only)
Short, D.P.G., Puri, K., Sandoya, G.V., Simko, I., Hayes, R.J., Subbarao, K.V. 2017. Characterization of Verticillium dahliae disease reactions in lettuce differential cultivars. American Phytopathological Society Annual Meeting, August 5-9, 2017, San Antonio, Texas.
Genetic characterization of resistance to Sclerotinia in lettuce cultivar Eruption - (Abstract Only)
Mamo, B.E., Hayes, R.J., Truco, M.J., Michelmore, R., Subbarao, K.V., Simko, I. 2017. Genetic characterization of resistance to Sclerotinia in lettuce cultivar Eruption. American Phytopathological Society Annual Meeting, August 5-9, 2017, San Antonio, Texas.
Lettuce and spinach breeding - (Abstract Only)
Simko, I., McCreight, J.D., Mou, B. 2017. Lettuce and spinach breeding. California Leafy Greens Research Program Annual Meeting. March 14, 2017, Pismo Beach, California.
Nondestructive phenotyping of lettuce plants in early stages of development with optical sensors - (Peer Reviewed Journal)
Simko, I., Hayes, R.J., Furbank, R.T. 2016. Nondestructive phenotyping of lettuce plants in early stages of development with optical sensors. Frontiers in Plant Science. 7:1-19.
Maturity-adjusted resistance of potato (Solanum tuberosum L.) cultivars to Verticillium wilt caused by Verticillium dahliae - (Peer Reviewed Journal)
Simko, I., Haynes, K.G. 2017. Maturity-adjusted resistance of potato (Solanum tuberosum L.) cultivars to Verticillium wilt caused by Verticillium dahliae. American Journal of Potato Research. 94:173–177.
Advancements in utilizing molecular markers in lettuce breeding - (Proceedings)
Simko, I. 2017. Advancements in utilizing molecular markers in lettuce breeding. 4th International Symposium on Molecular Markers in Horticulture, International Society for Horticultural Science. March 7-10, 2017, Napier, New Zealand.
Lettuce and spinach breeding - (Proceedings)
Simko, I., McCreight, J.D., Mou, B., Klosterman, S.J. 2016. Lettuce and spinach breeding. California Leafy Greens Research Program Mid-Year Meeting. October 4, 2016, Salinas, California.
Phenomic approaches and tools for phytopathologists - (Peer Reviewed Journal)
Simko, I., Jimenez-Berni, J.A., Sirault, X.R.R. 2016. Phenomic approaches and tools for phytopathologists. Phytopathology. 107:6-17.
Genetics of the partial resistance against race 2 of Verticillium dahliae in lettuce - (Proceedings)
Sandoya, G.V., Truco, M., Bertier, L., Subbarao, K.V., Michelmore, R., Simko, I., Hayes, R.J. 2016. Genetics of the partial resistance against race 2 of Verticillium dahliae in lettuce. American Society for Horticultural Science Annual Meeting. Available: https://ashs.confex.com/ashs/2016/webprogram/Paper24442.html.
Lettuce and spinach breeding - (Proceedings)
Simko, I., Hayes, R.J., Mou, B., McCreight, J.D. 2016. Lettuce breeding. California Leafy Greens Research Board Annual Meeting. Available: http://calgreens.org/wp-content/uploads/2016/06/Lettuce-Breeding-USDA-ARS-Simko-Mou-and-McCreight.pdf.
Genetic characterization of quantitative resistance to Bremia lactucae, the causal organism of lettuce downy mildew - (Proceedings)
Parra, L., Simko, I., Michelmore, R. 2016. Genetic characterization of quantitative resistance to Bremia lactucae, the causal organism of lettuce downy mildew. American Phytopathological Society Annual Meeting. Available: http://www.apsnet.org/meetings/annual/abstracts/pages/abstractdetail.aspx?MID=550.
Breeding lettuce for improved fresh-cut processing - (Peer Reviewed Journal)
Hayes, R.J., Simko, I. 2016. Breeding lettuce for improved fresh-cut processing. Acta Horticulturae. 1141:65-76. doi: 10.17660/ActaHortic.2016.1141.7.
High-resolution DNA melting analysis in plant research - (Peer Reviewed Journal)
Simko, I. 2016. High-resolution DNA melting analysis in plant research. Trends in Plant Science. 21(6):528-537.
Genetics of resistance against lettuce downy mildew - (Proceedings)
Parra, L., Ochoa, O.E., Mchale, L.K., Christopoulou, M., Simko, I., Michelmore, R. 2016. Genetics of resistance against lettuce downy mildew. Plant and Animal Genome Conference Proceedings. Available: https://pag.confex.com/pag/xxiv/webprogram/Paper19545.html.
Assessing genetic variation in lettuce for traits related to nitrogen use efficiency using susceptibility and relative efficiency indices - (Proceedings)
Gonzalez, M.M., Truco, M., Michelmore, R., Smith, R., Cahn, M., Simko, I., Hayes, R.J. 2015. Assessing genetic variation in lettuce for traits related to nitrogen use efficiency using susceptibility and relative efficiency indices. ASA, CSSA, and SSSA Annual Meeting. Available: https://scisoc.confex.com/scisoc/2015am/webprogram/Paper93179.html.
Comparing the predictive abilities of phenotypic and marker-assisted selection methods in a biparental lettuce population Reprint Icon - (Peer Reviewed Journal)
Hadasch, S., Simko, I., Hayes, R.J., Ogutu, J.O., Piepho, H.-P. 2016. Comparing the predictive abilities of phenotypic and marker-assisted selection methods in a biparental lettuce population. The Plant Genome. 9(1):1-11.
Application of chlorophyll fluorescence imaging and hyperspectral imaging in evaluation of decay in fresh-cut lettuce - (Abstract Only)
Simko, I., Jimenez-Berni, J.A., Furbank, R.T. 2015. Application of chlorophyll fluorescence imaging and hyperspectral imaging in evaluation of decay in fresh-cut lettuce. International Plant and Algal Phenomics Meeting, June 27-30, 2015, Prague, Czech Republic.
Breeding lettuce for fresh-cut processing - (Abstract Only)
Hayes, R.J., Simko, I. 2015. Breeding lettuce for fresh-cut processing. III International Conference on Fresh-cut Produce: Maintaining Quality and Safety, September 13-18, 2015, Davis, California.
Analysis of bibliometric indicators to determine citation bias - (Peer Reviewed Journal)
Simko, I. 2015. Analysis of bibliometric indicators to determine citation bias. Palgrave Communications. doi: 10.1057/palcomms.2015.11.
Resistance to downy mildew in lettuce ‘La Brillante’ is conferred by dm50 gene and multiple QTL - (Peer Reviewed Journal)
Simko, I., Ochoa, O.E., Pel, M.A., Tsuchida, C., Forcada, C.F., Hayes, R.J., Truco, M.J., Antonise, R., Galeano, C.H., Michelmore, R.W. 2015. Resistance to downy mildew in lettuce ‘La Brillante’ is conferred by dm50 gene and multiple QTL. Phytopathology. 105:1220-1228.
Detection of decay in fresh-cut lettuce using hyperspectral imaging and chlorophyll fluorescence imaging - (Peer Reviewed Journal)
Simko, I., Jimenez-Berni, J.A., Furbank, R.T. 2015. Detection of decay in fresh-cut lettuce using hyperspectral imaging and chlorophyll fluorescence imaging. Postharvest Biology and Technology. 106:44–52.
Downy mildew disease promotes the colonization of romaine lettuce by Escherichia coli O157:H7 and Salmonella enterica Reprint Icon - (Peer Reviewed Journal)
Simko, I., Zhou, Y., Brandl, M. 2015. Downy mildew disease promotes the colonization of romaine lettuce by Escherichia coli O157:H7 and Salmonella enterica. BMC Microbiology. 15:19. doi: 10.1186/s12866-015-0360-5.
Inheritance of decay of salad-cut lettuce in a recombinant inbred line population from ‘Salinas 88’ x ‘La Brillante’ - (Peer Reviewed Journal)
Hayes, R.J., Galeano, C.H., Luo, Y., Antonise, R., Simko, I. 2014. Inheritance of decay of salad-cut lettuce in a recombinant inbred line population from ‘Salinas 88’ x ‘La Brillante’. Journal of the American Society for Horticultural Science. 139:388-398.
Characterization and performance of 16 new inbred lines of lettuce Reprint Icon - (Peer Reviewed Journal)
Simko, I., Hayes, R.J., Bull, C.T., Mou, B., Luo, Y., Trent, M.A., Atallah, A.J., Ryder, E.J., Sideman, R.G. 2014. Characterization and performance of 16 new inbred lines of lettuce. HortScience. 49:679-687.
Notice of release of iceberg, romaine, and leaf lettuce breeding lines with improved disease resistance - (Germplasm Registration)
Simko, I., Hayes, R.J. 2014. Notice of release of iceberg, romaine, and leaf lettuce breeding lines with improved disease resistance. Germplasm Release. Available: http://calgreens.org/wp-content/uploads/2014/03/USDA-Releases-Sixteen-New-Breeding-LInes-of-Lettuce1.pdf.
QTL mapping, association mapping and marker assisted breeding in lettuce - (Proceedings)
Simko, I. 2014. QTL mapping, association mapping and marker assisted breeding in lettuce. American Seed Trade Association Conference, January 23-27, 2014, Monterey, California. Available: http://biodiagnostics.net/wp-content/uploads/2014/04/Dr.-Simko-ASTA-on-Lettuce-breeding-strategies-2014.pdf.
Development of a high-density intra-specific linkage map of lettuce using genotyping by sequencing (GBS) - (Proceedings)
Galeano, C.H., Froenicke, L., Duitama, J., Kozik, A., Reyes-Chin-Wo, S., Simko, I., Hayes, R.J., Michelmore, R. 2014. Development of a high-density intra-specific linkage map of lettuce using genotyping by sequencing (GBS). Plant and Animal Genome XXII Conference, January 11-15, 2014, San Diego, California. P686.
Baby leaf lettuce germplasm enhancement: developing diverse populations with resistance to bacterial leaf spot caused by Xanthomonas campestris pv. vitians - (Peer Reviewed Journal)
Hayes, R.J., Trent, M.A., Mou, B., Simko, I., Gebben, S.J., Bull, C.T. 2014. Baby leaf lettuce germplasm enhancement: developing diverse populations with resistance to bacterial leaf spot caused by Xanthomonas campestris pv. vitians. HortScience. 49:18–24.
Identification of QTLs conferring resistance to downy mildew in legacy cultivars of lettuce - (Peer Reviewed Journal)
Simko, I., Atallah, A.J., Ochoa, O., Antonise, R., Galeano, C., Truco, M.J., Michelmore, R. 2013. Identification of QTLs conferring resistance to downy mildew in legacy cultivars of lettuce. Scientific Reports. DOI:10.1038/srep02875.
Genome-wide association of 10 horticultural traits with expressed sequence tag-derived SNP markers in a collection of lettuce lines Reprint Icon - (Peer Reviewed Journal)
Kwon, S.J., Simko, I., Hellier, B.C., Mou, B., Hu, J. 2013. Genome-wide association of 10 horticultural traits with expressed sequence tag-derived SNP markers in a collection of lettuce lines. The Crop Journal. 1(1):25-33. DOI: 10.1016/j.cj.2013.07.014.
Yield gains in leafy vegetables - (Book / Chapter)
Simko, I., Hayes, R.J., Mou, B., McCreight, J.D. 2014. Yield gains in leafy vegetables. In: Smith, S., Diers, B., Specht, J., Carver, B., editors. Yield gains in major U.S. field crops. CSSA Special Publications 33. Madison, WI: American Society of Agronomy, Inc., Crop Science Society of America, Inc., and Soil Science Society of America, Inc. p. 53-86.
Evaluation and Quantitative trait loci mapping of resistance to powdery mildew in lettuce - (Peer Reviewed Journal)
Simko, I., Rauscher, G., Sidemann, R., McCreight, J.D., Hayes, R.J. 2013. Evaluation and Quantitative trait loci mapping of resistance to powdery mildew in lettuce. Plant Pathology. DOI: 10.1111/ppa.12087.
Development of genomic SSR markers for fingerprinting lettuce (Lactuca sativa L.) cultivars and mapping genes - (Peer Reviewed Journal)
Rauscher, G., Simko, I. 2013. Development of genomic SSR markers for fingerprinting lettuce (Lactuca sativa L.) cultivars and mapping genes. BMC Plant Biology. 13:11.
Marker-assisted selection for disease resistance in lettuce - (Book / Chapter)
Simko, I. 2013. Marker-assisted selection for disease resistance in lettuce. In: Varshney, R.K., Tuberosa, R., editors. Translational genomics for crop breeding. Vol. I: Biotic stresses. Ames, IA: John Wiley & Sons, Inc. p. 267-289.
Environmental factors contributing to development of lettuce dieback disease and genomic characterization of lettuce necrotic stunt virus - (Abstract Only)
Wintermantel, W.M., Simko, I. 2012. Environmental factors contributing to development of lettuce dieback disease and genomic characterization of lettuce necrotic stunt virus. Phytopathology. 102:S4.136.
AUDPC and AUDPS: What is the Difference? - (Abstract Only)
Simko, I., Piepho, H. 2012. AUDPC and AUDPS: What is the Difference? Phytopathology. 102:S4.110.
Computing Integrated Ratings from Heterogeneous Phenotypic Assessments: A Case Study of Lettuce Postharvest Quality and Downy Mildew Resistance - (Peer Reviewed Journal)
Simko, I., Hayes, R.J., Kramer, M.H. 2012. Computing integrated ratings from heterogeneous phenotypic assessments: A case study of lettuce postharvest quality and downy mildew resistance. Crop Science. 52:2131-2142.
Empirical evaluation of DArT, SNP, and SSR marker-systems for genotyping, clustering, and assigning sugar beet hybrid varieties into populations - (Peer Reviewed Journal)
Simko, I., Eujayl, I.A., Van Hintum, Jl, T. 2012. Empirical evaluation of DArT, SNP, and SSR marker-systems for genotyping, clustering, and assigning sugar beet hybrid varieties into populations. Plant Science. 184:54-62.
The area under the disease progress stairs: calculation, advantage, and application - (Peer Reviewed Journal)
Simko, I., Piepho, H. 2012. The area under the disease progress stairs: calculation, advantage, and application. Phytopathology. 102:381-389.
Developing lettuce with improved quality for processed salads. - (Abstract Only)
Hayes, R.J., Truco, M.J., Mchale, L.K., Michelmore, R.W., Antonise, R., Hand, P., Simko, I. 2011. Developing lettuce with improved quality for processed salads. Eucarpia Conference on Lettuce and Leafy Vegetables. August 24, 2011, Lille, France.
Mapping dominant negative mutation for triforine sensitivity in lettuce and its use as a selectable marker for detecting hybrids. - (Peer Reviewed Journal)
Simko, I., Hayes, R.J., Truco, M.J., Michelmore, R.W. 2011. Mapping dominant negative mutation for triforine sensitivity in lettuce and its use as a selectable marker for detecting hybrids. Euphytica. 182(2):157-166.
Combining phenotypic data from ordinal rating scales in multiple plant experiments - (Peer Reviewed Journal)
Simko, I., Piepho, H. 2011. Combining phenotypic data from ordinal rating scales in multiple plant experiments. Trends in Plant Science. 16:235-237.
Application of Hi-Res Melting Approach for Mapping Resistance Genes and Marker-assisted Selection in Lettuce - (Other)
Simko, I. 2011. Application of Hi-Res Melting Approach for Mapping Resistance Genes and Marker-assisted Selection in Lettuce. Plant and Animal Genome Conference. Online.
Iceberg lettuce breeding lines with resistance to Verticillium wilt caused by race 1 isolates of Verticillium dahliae. - (Peer Reviewed Journal)
Hayes, R.J., Maruthachalam, K., Vallad, G.E., Klosterman, S.J., Simko, I., Luo, Y., Subbarao, K.V. 2011. Iceberg lettuce breeding lines with resistance to Verticillium wilt caused by race 1 isolates of Verticillium dahliae. HortScience. 46(3):501-504.
Evaluation of the RPi-ber late blight resistance gene for tuber resistance in the field and laboratory. - (Peer Reviewed Journal)
Mayton, H., Rauscher, G., Simko, I., Fry, W. 2011. Evaluation of the RPi-ber late blight resistance gene for tuber resistance in the field and laboratory. Plant Breeding. 130:464-468.
Combining partially ranked data in plant breeding and biology: II. Analysis with Rasch model. - (Peer Reviewed Journal)
Simko, I., Lincare, J.M. 2010. Combining partially ranked data in plant breeding and biology: II. Analysis with Rasch model.. Communications in Biometry and Crop Science (CBCS). 2010, Vol 5, Pages 56-65.
Combining partially ranked data in plant breeding and biology: I. Rank aggregating methods. - (Peer Reviewed Journal)
Simko, I., Pechenick, D.A. 2010. Combining partially ranked data in plant breeding and biology: I. Rank aggregating methods.. Communications in Biometry and Crop Science (CBCS), Year 2010, volume 5, pages 41-55.
SM09A and SM09B: Romaine Lettuce Breeding Lines Resistant to Dieback and with Improved Shelf-life. - (Peer Reviewed Journal)
Simko, I., Hayes, R.J., Subbarao, K.V., Sideman, R.G. 2010. SM09A and SM09B: Romaine Lettuce Breeding Lines Resistant to Dieback and with Improved Shelf-life.. HortScience,Year 2010, volume 45, pages 670-672.
Association mapping and marker-assisted selection of the lettuce dieback resistance gene Tvr1. - (Peer Reviewed Journal)
Simko, I., Pechenick, D.A., Mchale, L.K., Truco, M.J., Ochoa, O.E., Michelmore, R.W., Scheffler, B.E. 2009. Association mapping and marker-assisted selection of the lettuce dieback resistance gene Tvr1.. Biomed Central (BMC) Plant Biology, Year 2009, volume 9, article number 135.
Development of molecular markers for marker-assisted selection in lettuce (Lactuca sativa). - (Peer Reviewed Journal)
Simko, I., Pechenick, D.A., Mchale, L.K., Truco, M.J., Ochoa, O.E., Michelmore, R.W., Scheffler, B.E. 2010. Development of molecular markers for marker-assisted selection in lettuce (Lactuca sativa). Acta Horticulture Proceedings, Year 2010, volume 859, pages 401-408.
QTL mapping of resistance to Powdery Mildew in lettuce. - (Abstract Only)
Rauscher, G.M., Hayes, R.J., Simko, I. 2009. QTL mapping of resistance to Powdery Mildew in lettuce. Phytopathology 99:S107.
Development of molecular markers for marker-assisted selection in lettuce (Lactuca sativa). - (Abstract Only)
FOLIAR AND TUBER BLIGHT RESISTANCE IN A SOLANUM TUBEROSUM BREEDING LINES. - (Review Article)
Mayton, H., Griffiths, H., Simko, I., Cheng, S., Lorenzen, J., De Jong, W., Fry, W.E. 2009. FOLIAR AND TUBER BLIGHT RESISTANCE IN A SOLANUM TUBEROSUM BREEDING LINES.. Plant Breeding.DOI:10.1111/J.1439-0523.01671.x
Association analysis of beet curly top disease resistant genes in sugarbeet - (Abstract Only)
Eujayl, I.A., Simko, I., Strausbaugh, C.A. 2009. Association analysis of beet curly top disease resistant genes in sugarbeet [Abstract]. Proceedings of 35th Biennial Meeting of American Society of Sugar Beet Technologists: Section B&E. Paper No. 1.
Development of EST-SSR Markers for the Study of Population Structure in Lettuce (Lacutca sativa L.). - (Peer Reviewed Journal)
Simko, I. 2009. Development of EST-SSR Markers for the Study of Population Structure in Lettuce (Lacutca sativa L.). Journal of Heredity 180: 256-262.
Effect of Isolate, Environment and a Defeated R-gene (RPi-ber) on Quantitative Resistance of Potato to Late Blight - (Peer Reviewed Journal)
Rauscher, G.M., Mayton, H., Bonierbale, M., Simko, I., Smart, C., Grunwald, N.J., Fry, W. Effect of Isolate, Environment and a Defeated R-gene (RPi-ber) on Quantitative Resistance of Potato to Late Blight. American Phytopathological Society Annual Meeting, Minneapolis, Minnesota, July 26-July 30. Phytopathology 98:S130.
MAPPING LOCI FOR CHLOROSIS ASSOCIATED WITH CHLOROPHYLL B DEFICIENCY IN POTATO - (Peer Reviewed Journal)
Simko, I., Van Den Berg, J.H., Vreugdenhil, D., Ewing, E.E. 2008. Mapping loci for chlorosis associated with chlorophyll b deficiency in potato. Euphytica Vol 162, Pages 99-107, 2008.
Populations structure in cultivated lettuce (Lactuca sativa L.) and its impact on assocation mapping. - (Peer Reviewed Journal)
Simko, I., Hu, J. Populations structure in cultivated lettuce (Lactuca sativa L.) Journal of the American Society for Horticultural Science, Vol. 133, Pages 61-68, 2008.
Comparison of the two pathogenic systems: Bremia Lactucae on Lactuca, and Phytophthora infestans on Solarum - (Abstract Only)
Simko, I. 2007. Comparison of the two pathogenic systems: Bremia Lactucae on Lactuca, and Phytophthora infestans on Solarum. Downy Mildews 2nd International Symposium. Olomouc, Czech Republic, July 2-7, 2007.
From Association Mapping to Marker-Assisted Selection: Experimental Design and Application. - (Abstract Only)
Simko, I. 2007. From Association Mapping to Marker-Assisted Selection: Experimental Design and Application. Phytopathology 97:S149..
Effect of Population Structure on Association Mapping in Cultivated Lettuce. - (Abstract Only)
Simko, I., Hu, J. 2007. Effect of Population Structure on Association Mapping in Cultivated Lettuce. In Eucarpia Leafy Vegetables 2007 Conference Abstracts. Warwick, UK, April 18-20, 2007.
Foliar and tuber late blight resistance in a Solanum tuberosum potato mapping population - (Abstract Only)
Mayton, H., Simko, I., Dejong, W., Fry, W. 2006. Foliar and tuber late blight resistance in a Solanum tuberosum potato mapping population. American Phytopathological Society Annual Meeting, Quebec City, Canada, July 29-August 2, 2006. Phytopathology 96:S74.
CHARACTERIZATION AND MAPPING OF RPI-BER, A NOVEL POTATO LATE BLIGHT RESISTANCE GENE FROM SOLANUM BERTHAULTII - (Peer Reviewed Journal)
Rancher, G., Smart, C.D., Simko, I., Bonierbale, M., Mayton, H., Greenland, A., Fry, W.E. 2006. Characterization and mapping of rpi-ber, a novel potato late blight resistance gene from solanum berthaultii. Theoretical and Applied Genetics. 112(4):674-687.
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