Denisse Peña-Tapia

Prof. Denisse Peña-Tapia

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Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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28 February 2025 in Nanomaterials
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SCStefania Tania Caguana
Stefania Tania Caguana
CCChristian Cruzat
Christian Cruzat
DRDavid Herrera Robalino
David Herrera Robalino
DPDenisse Peña-Tapia
Denisse Peña-Tapia
VAValeria Arévalo
Valeria Arévalo
MVMARIA EULALIA VANEGAS
MARIA EULALIA VANEGAS
Nanoparticles (NPs) have generated significant interest in various fields due to the unique properties that materials exhibit at the nanoscale. This study presents a comparative analysis of copper nanoparticles (Cu-NPs) and cobalt nanoparticles (Co-NPs) synthesized via conventional solvothermal and green hydrothermal synthesis using ethylene glycol and Medicago sativa extract, respectively. The conventional solvothermal synthesis showed higher efficiency for both Cu-NPs and Co-NPs with yields of 32.5% and 26.7%, respectively. Characterization through UV–visible spectroscopy (UV–vis), Fourier-transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM) revealed that while solvothermal synthesis produced larger particles (76.5 nm for Cu-NPs, 86.8 nm for Co-NPs), the green hydrothermal method yielded smaller particles (53.8 nm for Cu-NPs, 67.7 nm for Co-NPs) with better control over particle size distribution and spherical morphology, showing minimal agglomeration. UV–vis confirmed metal oxide formation, while FTIR showed complex patterns in NPs (green hydrothermal), indicating plant extract compounds. Antifungal evaluation against Pseudocercospora fijiensis showed complete inhibition at 2000 ppm for both NP types, with no mycelial growth after 30 days. When integrated into chitosan, solvothermal NPs produced rougher surfaces, and scanning electron microscope (SEM) confirmed the presence of copper and cobalt in the nanocomposites. This study provides insights into the synthesis of nanoparticles using an environmentally friendly process and their microbiological applications for future use in organic agriculture.

12 August 2022 in Diversity
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APAngela Vanessa Pacheco
Angela Vanessa Pacheco
MBMilton Barcos-Arias
Milton Barcos-Arias
JNJaime Naranjo-Morán
Jaime Naranjo-Morán
DPDenisse Peña-Tapia
Denisse Peña-Tapia
RMRebeca Elizabeth Moreira-Gómez
Rebeca Elizabeth Moreira-Gómez
Ericaceae are a group of plants with biotechnological and commercial importance. These plants establish symbiotic associations with a wide group of mycorrhizal fungi. National and global studies have focused on two of them: arbuscular endomycorrhizae and ectomycorrhizae. The most recent type of mycorrhiza recorded is the cavendishioid ectendomycorrhizae. The cavendishioid is one of the least-studied and understood mycorrhizae, along with monotropoid and arbutoid mycorrhizae. Among the potentialities of these ectendomycorrhizae are the alleviation of environmental stress, the facilitation of establishment, survival, the ability to form dual mycorrhizae, and their importance as a fundamental biological element of plant ecological successions. However, the factors that influence or correlate with the diversity of some of these fungal guilds, as well as the functional significance of their associations, are still unknown. The present review focuses on ericoid mycorrhiza from Ecuador in order to promote their study and thus take advantage of the benefits that they provide to endemic species and those of commercial interest. This material contributes significantly to reducing research gaps and channeling applied projects in the biological sciences.

30 April 2020 in Lankesteriana: International Journal on Orchidology
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GMGabriela P. Maldonado
Gabriela P. Maldonado
LYLuis A. Yarzábal
Luis A. Yarzábal
JCJuan Cevallos-Cevallos
Juan Cevallos-Cevallos
ECEduardo J. Chica
Eduardo J. Chica
DPDenisse Peña-Tapia
Denisse Peña-Tapia
Seeds of many orchids rely on the presence of fungi to trigger the germination process and even to initiate the full development of protocorms. While attention has been directed towards the study of mycorrhizal fungi, the diversity and functions of endophytic fungi from orchid roots remain underexplored, and few studies have verified their ecological role. This is the case of Pleurothallis coriacardia, an endemic green Neotropical orchid with both epiphytic and lithophytic habits growing in High-Andean montane forests. In the present study, we screened the cultivable fraction of the endophytic fungi colonizing the roots of mature plants of P. coriacardia using ITS rDNA markers. We also tested the potential of these endophytic fungi to improve embryo development and seed germination. Most of the isolated endophytes were classified within Psathyrellaceae. Some isolates, identified as members of the Ilyonectria and Coprinellus genera, significantly promoted embryo development in vitro in P. coriacardia seeds, a result that highlights the ecological roles these endophytic fungi may play in nature. Keywords: Andean montane forest, embryo development, epiphytic orchids, Ilyonectria, lithophytic orchids, Psathryrellaceae

6 July 2023 in Plants
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VMValeria Muñoz
Valeria Muñoz
DCDiana Curillo
Diana Curillo
SGSebastián Gómez
Sebastián Gómez
LMLissette Moreno-Peña
Lissette Moreno-Peña
DPDenisse Peña-Tapia
Denisse Peña-Tapia
DQDiego F Quito-Avila
Diego F Quito-Avila
Babaco (Vasconcellea x heilbornii), a fruit-bearing vegetatively propagated crop native to Ecuador, is appreciated for its distinctive flavor and nutritional properties. The aim of this research was to determine a functional protocol for tissue culture propagation of virus-free babaco plants including in vitro establishment, multiplication, rooting, and acclimation. First, symptomless babaco plants from a single commercial nursery were analyzed for virus detection and cared for using different disinfection treatments in the greenhouse to reduce contamination during the in vitro establishing step, and three cytokinins, 6-(γ,γ-Dimethylallylamino) purine (2IP), 6-Benzylaminopurine (BAP), and Thidiazuron (TDZ), were used to determine the best hormone for multiplication. The best treatment for plant disinfection was the weekly application of copper sulfate at the greenhouse and a laboratory disinfection using ethanol (EtOH) (70%), Clorox (2%), and a solution of povidone iodine (2.5%), with an 80% survival during in vitro plant establishment. TDZ showed a better multiplication rate when compared with other hormones, and 70% of the rooted plants were successfully acclimated at the greenhouse. Generated plants were virus-free when tested against babaco mosaic virus (BabMV) and papaya ringspot virus (PRSV), two of the most important viruses that can affect babaco. An efficient protocol to produce virus-free babaco plants was elaborated with an integrated use of viral diagnostic tools to ensure the production of healthy start material to farmers.

22 December 2014 in MASKANA
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DPDenisse Peña-Tapia
Denisse Peña-Tapia
MRMélida Rocano
Mélida Rocano
JSJazmín Salazar
Jazmín Salazar
CTCarlos Torres
Carlos Torres
The walnut (Juglans neotropica) is a species of great potential for conservation projects and eco-agro-production in the Andean region. However, low germination capacity limits its spread for reforestation. The aim of this study was to determine the effect of treatment with Thidiazuron (TDZ) and 6-Benzylaminopurine (BAP) on in vitro shoot induction of J. neotropica. The micro plantlets treated with BAP produced more shoots than those treated with TDZ. The micro plantlets treated with BAP and TDZ in turn generated more shoots than the non-treated micro plantlets. In the test, the effect of concentration of BAP and TDZ in the medium was also evaluated; however not statistically significant differences between the tested concentrations were detected. In summary, findings indicate that the treatment with cytokines, BAP specifically, increases the number of shoots produced by micro plantlets J. neotropica. It is believed that this treatment can be applied on projects of mass propagation of this species within the frame of reforestation programs. El nogal (Juglans neotropica) es una especie de gran potencial para proyectos de conservación y agro-productivos en la eco-región Andina. No obstante, su baja capacidad germinativa limita su propagación para reforestación. El objetivo de este estudio fue determinar el efecto del tratamiento con Thidiazuron (TDZ) y 6-Bencilaminopurina (BAP) en la inducción in vitro de brotes de J. neotropica. Las microplántulas tratadas con BAP produjeron más brotes que aquellas tratadas con TDZ. Las microplántulas tratadas con BAP y TDZ generaron a su vez más brotes que las no-tratadas. En el ensayo se evaluó también el efecto de la concentración de BAP y TDZ en el medio pero no se detectaron diferencias estadísticamente significativas entre las concentraciones evaluadas. En conjunto, nuestros resultados indican que el tratamiento con cito-quininas, específicamente BAP, incrementa el número de brotes producidos por microplántula de J. neotropica, pudiendo aplicarse este tratamiento en proyectos de propagación masiva de esta especie para sostener programas de reforestación.

12 August 2025 in Frontiers in Plant Science
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DPDenisse Peña-Tapia
Denisse Peña-Tapia
PVPaulina Villena
Paulina Villena
DCDiana Curillo
Diana Curillo
CJCarlos A. Jiménez
Carlos A. Jiménez
EOEduardo Ordoñez
Eduardo Ordoñez
OJOswaldo Jadán
Oswaldo Jadán
Introduction: Macleania rupestris, an ecologically and culturally important species of the Ericaceae family, inhabits the montane forests of southern Ecuador and exhibits significant but understudied intraspecific morphological variation. Understanding this variation and its environmental drivers is crucial for effective conservation and restoration planning, particularly in a changing climate.Methods: We analyzed 15 quantitative traits in 200 individuals from four populations located in the Azuay and Cañar provinces to identify morphological groups and assess their environmental drivers. Hierarchical clustering and Random Forest classification were employed to detect distinct morphological groups. Additionally, generalized linear models were used to evaluate the influence of climatic seasonality and spatial autocorrelation on the most relevant traits.Results: We identified two distinct morphological groups, primarily differentiated by seed number per fruit, fruit humidity, fruit length and width, and petiole length traits that together explained over 75% of the observed variation. Climatic seasonality and spatial autocorrelation significantly influenced these key traits. Notably, seed number and fruit length responded strongly to variations in temperature and precipitation, while traits such as fruit humidity and petiole length showed moderate sensitivity to environmental gradients. A Random Forest classification model, based on the most relevant traits, achieved 99.5% accuracy, enabling robust assignment of new individuals into morphological groups.Discussion: Our findings highlight the influence of environmental heterogeneity on intraspecific differentiation in M. rupestris and provide evidence for local adaptation along climatic gradients. This study offers a novel framework for trait-based classification and emphasizes the importance of integrating morphological variation and environmental factors into conservation planning. By identifying environmentally driven morphological groups, these results can inform seed sourcing strategies and restoration efforts aimed at enhancing ecosystem resilience in the montane forests of southern Ecuador.