Siela Nikolova Maximova, Ph.D.

Siela Nikolova Maximova, Ph.D.

  • Research Professor of Plant Biotechnology
421 Life Sciences Bldg.
University Park, PA 16802

Areas of Expertise

  • Plant Biotechnology
  • Plant Functional Genomics
  • Plant Tissue Culture
  • Plant Propagation
  • Plant Disease Resistance
  • Plant – Microbes Interactions


  • Ph.D. Plant Physiology, The Pennsylvania State University, University Park, PA
  • M.S. Agricultural Engineering & Horticulture, Agricultural University, Plovdiv, Bulgaria
  • B.S. Agricultural Engineering & Horticulture, Agricultural University, Plovdiv, Bulgaria


Inter-species functional compatibility of the Theobroma cacao and Arabidopsis FT orthologs
BMC Plant Biology, Prewitt, S. F., Shalit-Kaneh, A., Maximova, S. N., Guiltinan, M. J., 2021

Cadmium phytoextraction by Helianthus annuus (sunflower), Brassica napus cv Wichita (rapeseed), and Chyrsopogon zizanioides (vetiver)
Chemosphere, Benavides, Bolaños J., Drohan, P. J., Spargo, J. T., Maximova, S. N., Guiltinan, M. J., Miller, D. A., 2021

Clovamide, a Hydroxycinnamic Acid Amide, Is a Resistance Factor Against Phytophthora spp. in Theobroma cacao
Frontiers in Plant Science, Knollenberg, Benjamin J., Li, Guo Xing, Lambert, Joshua D., Maximova, Siela N., Guiltinan, Mark J., 2020

Antiradical Activity of Hydrolysates and Extracts from Mollusk A. broughtonii and Practical Application to the Stabilization of Lipids.
Foods (Basel, Switzerland), Tabakaeva, O, Piekoszewski, W, Kalenik, T, Maximova, Siela, Tabakaev, A, Poleshyk, D, Proniewicz, L, 2020

Metabolomic profile of cacao cell suspensions growing in blue light/dark conditions with potential in food biotechnology
Plant Cell, Tissue and Organ Culture, Gallego, Adriana M., Rojas, Luisa F., Rodriguez, Héctor A., Mora, Conrado, Atehortúa, Lucía, Urrea, Aura I., Guiltinan, Mark J., Maximova, Siela N., Gaquerel, Emmanuel, Zuluaga, Martha, Pabón-Mora, Natalia, 2019

Resistant and susceptible cacao genotypes exhibit defense gene polymorphism and unique early responses to Phytophthora megakarya inoculation
Plant Molecular Biology, Pokou, Désiré N., Fister, Andrew S., Winters, Noah, Tahi, Mathias, Klotioloma, Coulibaly, Sebastian, Aswathy, Marden, James H., Maximova, Siela N., Guiltinan, Mark J., 2019

Widely distributed variation in tolerance to Phytophthora palmivora in four genetic groups of cacao
TREE GENETICS & GENOMES, Fister, Andrew, Leandro-Munoz, Mariela, Zhang, Dapeng, Marden, J, Tiffin, Peter, dePamphilis, C, Maximova, Siela, Guiltinan, M, 2019

Transcriptomic analyses of cacao cell suspensions in light and dark provide target genes for controlled flavonoid production
Scientific Reports, Gallego, Adriana M., Rojas, Luisa F., Parra, Oriana, Rodriguez, Héctor A., Mazo Rivas, Juan C., Urrea, Aura Inés, Atehortúa, Lucía, Fister, Andrew S., Guiltinan, Mark J., Maximova, Siela N., Pabón-Mora, Natalia, 2018

Glucocorticoid receptor-regulated TcLEC2 expression triggers somatic embryogenesis in Theobroma cacao leaf tissue
PLoS One, Fister, Andrew S., Landherr, Lena, Perryman, Melanie, Zhang, Yufan, Guiltinan, Mark J., Maximova, Siela N., 2018

Transient expression of CRISPR/Cas9 machinery targeting TcNPR3 enhances defense response in theobroma cacao
Frontiers in Plant Science, Fister, Andrew S., Landherr, Lena, Maximova, Siela N., Guiltinan, Mark J., 2018

Effects of microclimatic variables on the symptoms and signs onset of Moniliophthora roreri, causal agent of Moniliophthora pod rot in cacao
PLoS One, Leandro-Muñoz, Mariela E., Tixier, Philippe, Germon, Amandine, Rakotobe, Veromanitra, Phillips-Mora, Wilbert, Maximova, Siela, Avelino, Jacques, 2017

Protocol: Transient expression system for functional genomics in the tropical tree theobroma cacao L.
Plant Methods, Fister, Andrew S., Shi, Zi, Zhang, Yufan, Helliwell, Emily E., Maximova, Siela N., Guiltinan, Mark J., 2016

Enhanced resistance in Theobroma cacao against oomycete and fungal pathogens by secretion of phosphatidylinositol-3-phosphate-binding proteins
Plant Biotechnology Journal, Helliwell, Emily E., Vega-Arreguín, Julio, Shi, Zi, Bailey, Bryan, Xiao, Shunyuan, Maximova, Siela N., Tyler, Brett M., Guiltinan, Mark J., 2016

Tc-MYBPA an Arabidopsis TT2-like transcription factor and functions in the regulation of proanthocyanidin synthesis in Theobroma cacao
BMC Plant Biology, Liu, Yi, Shi, Zi, Maximova, Siela N., Payne, Mark J., Guiltinan, Mark J., 2015

Enhanced somatic embryogenesis in Theobroma cacao using the homologous BABY BOOM transcription factor
BMC Plant Biology, Florez, Sergio L., Erwin, Rachel L., Maximova, Siela N., Guiltinan, Mark J., Curtis, Wayne R., 2015

Proteome analysis during pod, zygotic and somatic embryo maturation of Theobroma cacao
Z. PFLANZENPHYSIOL., Niemenak, Nicolas, Kaiser, Edward, Maximova, Siela N., Laremore, Tatiana, Guiltinan, Mark J., 2015

Characterization of a stearoyl-acyl carrier protein desaturase gene family from chocolate tree, theobroma cacao L
Frontiers in Plant Science, Zhang, Yufan, Maximova, Siela N., Guiltinan, Mark J., 2015

Yield Performance and Bean Quality Traits of Cacao Propagated by Grafting and Somatic Embryo-derived Cuttings
Hortscience: A Publication of the American Society for Hortcultural Science, Goenaga, Ricardo, Guiltinan, Mark, Maximova, Siela, Seguine, Ed, Irizarry, Heber, 2015

Application of glycerol as a foliar spray activates the defence response and enhances disease resistance of Theobroma cacao
Molecular Plant Pathology, Zhang, Yufan, Smith, Philip, Maximova, Siela N., Guiltinan, Mark J., 2015

Two Theobroma cacao genotypes with contrasting pathogen tolerance show aberrant transcriptional and ROS responses after salicylic acid treatment
Journal of Experimental Botany, Fister, Andrew S., O'Neil, Shawn T., Shi, Zi, Zhang, Yufan, Tyler, Brett M., Guiltinan, Mark J., Maximova, Siela N., 2015

Applications of Genomics to the Improvement of Cacao

Genome-wide analysis reveals divergent patterns of gene expression during zygotic and somatic embryo maturation of Theobroma cacao L., the chocolate tree
BMC Plant Biology, Maximova, Siela N., Florez, Sergio, Shen, Xiangling, Niemenak, Nicolas, Zhang, Yufan, Curtis, Wayne, Guiltinan, Mark J., 2014

The Theobroma cacao B3 domain transcription factor TcLEC2 plays a duel role in control of embryo development and maturation
BMC Plant Biology, Zhang, Yufan, Clemens, Adam, Maximova, Siela N., Guiltinan, Mark J., 2014

Pervasive effects of a dominant foliar endophytic fungus on host genetic and phenotypic expression in a tropical tree
Frontiers in Microbiology, Mejía, Luis C., Herre, Edward A., Sparks, Jed P., Winter, Klaus, García, Milton N., Van Bael, Sunshine A., Stitt, Joseph, Shi, Zi, Zhang, Yufan, Guiltinan, Mark J., Maximova, Siela N., 2014

TcNPR3 from Theobroma cacao functions as a repressor of the pathogen defense response
BMC Plant Biology, Shi, Zi, Zhang, Yufan, Maximova, Siela N., Guiltinan, Mark J., 2013

Proanthocyanidin synthesis in Theobroma cacao: Genes encoding anthocyanidin synthase, anthocyanidin reductase, and leucoanthocyanidin reductase
BMC Plant Biology, Liu, Yi, Shi, Zi, Maximova, Siela, Payne, Mark J., Guiltinan, Mark J., 2013

Characterization of the basal angiosperm Aristolochia fimbriata
BMC Plant Biology, Bliss, Barbara J., Wanke, Stefan, Barakat, Abdelali, Ayyampalayam, Saravanaraj, Wickett, Norman, Wall, P. Kerr, Jiao, Yuannian, Landherr, Lena, Ralph, Paula E., Hu, Yi, Neinhuis, Christoph, Leebens-Mack, Jim, Arumuganathan, Kathiravetpilla, Clifton, Sandra W., Maximova, Siela N., Ma, Hong, dePamphilis, Claude W., 2013

Dynamic changes in pod and fungal physiology associated with the shift from biotrophy to necrotrophy during the infection of Theobroma cacao by Moniliophthora roreri
Physiological and Molecular Plant Pathology, Bailey, Bryan A., Crozier, Jayne, Sicher, Richard C., Strem, Mary D., Melnick, Rachel, Carazzolle, Marcelo F., Costa, Gustavo G.L., Pereira, Gonçalo A.G., Zhang, Dapeng, Maximova, Siela, Guiltinan, Mark, Meinhardt, Lyndel, 2013

Genetic and environmental manipulation of somatic embryo formation for plant improvement, Curtis, M. S., Florez, S., Maximova, S., Guiltinan, M., Curtis, W. R., 2013

Knockdown of FIBRILLIN4 gene expression in apple decreases plastoglobule plastoquinone content
PLoS One, Singh, Dharmendra K., Laremore, Tatiana N., Smith, Philip B., Maximova, Siela N., McNellis, Timothy W., 2012

Rootstock-regulated gene expression patterns associated with fire blight resistance in apple
BMC Genomics, Jensen, Philip J., Halbrendt, Noemi, Fazio, Gennaro, Makalowska, Izabela, Altman, Naomi, Praul, Craig, Maximova, Siela N., Ngugi, Henry K., Crassweller, Robert M., Travis, James W., McNellis, Timothy W., 2012

Expression of designed antimicrobial peptides in Theobroma cacao L. Trees reduces leaf necrosis caused by phytophthora spp., Mejía, Luis C., Guiltinan, Mark J., Shi, Zi, Landherr, Lena, Maximova, Siela N., 2012

Rootstock-regulated gene expression profiling in apple trees reveals genes whose expression levels are associated with fire blight resistance, Jensen, P. J., McNellis, T. W., Altman, N., Maximova, S. N., Crassweller, R. M., Halbrendt, N., Travis, J. W., Praul, C. A., Makalowska, I., 2011

The genome of Theobroma cacao
Nature Genetics, Argout, Xavier, Salse, Jerome, Aury, Jean Marc, Guiltinan, Mark J., Droc, Gaetan, Gouzy, Jerome, Allegre, Mathilde, Chaparro, Cristian, Legavre, Thierry, Maximova, Siela N., Abrouk, Michael, Murat, Florent, Fouet, Olivier, Poulain, Julie, Ruiz, Manuel, Roguet, Yolande, Rodier-Goud, Maguy, Barbosa-Neto, Jose Fernandes, Sabot, Francois, Kudrna, Dave, Ammiraju, Jetty Siva S., Schuster, Stephan C., Carlson, John E., Sallet, Erika, Schiex, Thomas, Dievart, Anne, Kramer, Melissa, Gelley, Laura, Shi, Zi, Bérard, Aurélie, Viot, Christopher, Boccara, Michel, Risterucci, Ange Marie, Guignon, Valentin, Sabau, Xavier, Axtell, Michael J., Ma, Zhaorong, Zhang, Yufan, Brown, Spencer, Bourge, Mickael, Golser, Wolfgang, Song, Xiang, Clement, Didier, Rivallan, Ronan, Tahi, Mathias, Akaza, Joseph Moroh, Pitollat, Bertrand, Gramacho, Karina, D'Hont, Anglique, Brunel, Dominique, Infante, Diogenes, Kebe, Ismael, Costet, Pierre, Wing, Rod, McCombie, W. Richard, Guiderdoni, Emmanuel, Quetier, Francis, Panaud, Olivier, Wincker, Patrick, Bocs, Stephanie, Lanaud, Claire, 2011