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

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

1636 E ALISAL ST
SALINAS, CA 93905

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

Projects
Genetics and Breeding of Lettuce, Spinach, Melon, and Related Species to Improve Production and Consumer-related Traits
In-House Appropriated (D)
  Accession Number: 434549
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
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.)
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., Mou, B., Simko, I. 2022. Identification of Quantitative Trait Loci Associated with Bacterial Leaf Spot Resistance in Baby Leaf Lettuce. Plant Disease. 106:2583-2590. 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.
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.
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.
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.
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.
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 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.
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.
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.
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.
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.
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