Héctor Herrera, Rafael Valadares, Guilherme Oliveira, Alejandra Fuentes, Leonardo Almonacid, Sidney Vasconcelos do Nascimiento, Yoav Bashan, Cesar Arriagada. 2018. Adaptation and tolerance mechanisms developed by mycorrhizal Bipinnula fimbriata plantlets (Orchidaceae) in a heavy metal-polluted ecosystem. Mycorrhiza  28: 651-663. (WOS. Impact Factor 3.069  Q2).  09 

Ivan Balic, Paula Vizoso, Ricardo Nilo-Poyanco, Dayan Sanhueza, Patricio Olmedo, Pablo Sepulveda, Cesar Arriagada, Bruno G. Defilippi, Claudio Meneses, Reinaldo Campos-Vargas. 2018. Transcriptome analysis during ripening of table grape berry cv.  Thompson Seedless. Plos One.    (WOS. Impact Factor: 2.740 Q2). journal.pone.0190087

Lagos, Claudio, Larsen, John, Correa, Estefanía Saucedo, Almonacid, L., Herrera, Héctor, Fuentes, Alejandra, & Arriagada, Cesar. 2018. Dual inoculation with mycorrhizal and saprotrophic fungi suppress the maize growth and development under phenanthrene exposure. Journal of Soil Science and Plant Nutrition, 18(3), 721-734 (WOS. Impact Factor 2.156 Q2). 

Patricio Olmedo, Adrián A. Moreno, Dayan Sanhueza, Iván Balic, Christian Silva-Sanzana, Baltasar Zepeda, Julian C. Verdonk, César Arriagada, Claudio Meneses, Reinaldo Campos-Vargas. 2018. A catechol oxidase AcPPO from cherimoya (Annona cherimola Mill.) is localized to the Golgi apparatus. Plant Science. 266:46–54. (WOS. Impact Factor: 3.591  Q1). j.plantsci.2017.10.012

Andres Fuentes-Ramirez, Marcia Barrientos, Leonardo Almonacid, Cesar Arriagada-Escamilla Christian Salas-Eljatib. 2018.  Short-term response of soil microorganisms, nutrients and plant recovery in fire-affected Araucaria araucana forests. Applied Soil Ecology, Volume 131, 99-106. (WOS. Impact Factor 3.187  Q2). j.apsoil.2018.08.010

Adaptation and tolerance mechanisms developed by mycorrhizal Bipinnula fimbriata plantlets (Orchidaceae) in a heavy metal-polluted ecosystem

Author Full Names: Herrera, Hector; Valadares, Rafael; Oliveira, Guilherme; Fuentes, Alejandra; Almonacid, Leonardo; Vasconcelos do Nascimento, Sidney; Bashan, Yoav; Arriagada, Cesar

Source Title: MYCORRHIZA

The adaptation and performance of orchid mycorrhizae in heavy metal-polluted soils have been poorly explored. In the present study, proteomic and metabolic approaches were used to detect physiological changes in orchid roots established in a heavy metal-polluted soil and to ascertain whether mycorrhizal fungi affect the metabolic responses of roots. Young Bipinnula fimbriata plantlets were established in control and heavy metal-polluted soils in a greenhouse. After 14 months, exudation of root organic acids, phenolics, percentage of mycorrhization, mineral content, and differential protein accumulation were measured. More root biomass, higher root colonization, and higher exudation rates of citrate, succinate, and malate were detected in roots growing in heavy metal-polluted soils. Higher accumulation of phosphorus and heavy metals was found inside mycorrhizal roots under metal stress. Under non-contaminated conditions, non-mycorrhizal root segments showed enhanced accumulation of proteins related to carbon metabolism and stress, whereas mycorrhizal root segments stimulated protein synthesis related to pathogen control, cytoskeleton modification, and sucrose metabolism. Under heavy metal stress, the proteome profile of non-mycorrhizal root segments indicates a lower induction of defense mechanisms, which, together with the stimulation of enzymes related to carotenoid biosynthesis and cell wall organization, may positively influence mycorrhizal fungi colonization. The results point to different metabolic strategies in mycorrhizal and non-mycorrhizal root segments that are exposed to heavy metal stress. The results indicate that root colonization by mycorrhizal fungi is stimulated to alleviate the negative effects of heavy metals in the orchids.

DOI: 10.1007/s00572-018-0858-4

UT (Unique WOS ID): WOS:000447241100006

Transcriptome analysis during ripening of table grape berry cv. Thompson Seedless

Author Full Names: Balic, Ivan; Vizoso, Paula; Nilo-Poyanco, Ricardo; Sanhueza, Dayan; Olmedo, Patricio; Sepulveda, Pablo; Arriagada, Cesar; Defilippi, Bruno G.; Meneses, Claudio; Campos-Vargas, Reinaldo

Source Title: PLOS ONE

Ripening is one of the key processes associated with the development of major organoleptic characteristics of the fruit. This process has been extensively characterized in climacteric fruit, in contrast with non-climacteric fruit such as grape, where the process is less understood. With the aim of studying changes in gene expression during ripening of non-climacteric fruit, an Illumina based RNA-Seq transcriptome analysis was performed on four developmental stages, between veraison and harvest, on table grapes berries cv Thompson Seedless. Functional analysis showed a transcriptional increase in genes related with degradation processes of chlorophyll, lipids, macromolecules recycling and nucleosomes organization; accompanied by a decrease in genes related with chloroplasts integrity and amino acid synthesis pathways. It was possible to identify several processes described during leaf senescence, particularly close to harvest. Before this point, the results suggest a high transcriptional activity associated with the regulation of gene expression, cytoskeletal organization and cell wall metabolism, which can be related to growth of berries and firmness loss characteristic to this stage of development. This high metabolic activity could be associated with an increase in the transcription of genes related with glycolysis and respiration, unexpected for a non-climacteric fruit ripening.

DOI: 10.1371/journal.pone.0190087

UT (Unique WOS ID): WOS:000419689600031

Dual inoculation with mycorrhizal and saprotrophic fungi suppress the maize growth and development under phenanthrene exposure

Author Full Names: Lagos, Claudio; Larsen, John; Saucedo Correa, Estefania; Almonacid, Leonardo; Herrera, Hector; Fuentes, Alejandra; Arriagada, Cesar


Polycyclic aromatic hydrocarbons (PAHs) belong to the group of persistent organic pollutants with detrimental impact on the environment and its living organisms. Soil acts as the main PAH sink why strategies to remediate PAH contaminated soil are needed. Inoculation with plant growth promoting and stress alleviating fungi such as arbuscular mycorrhizal (AM) fungi and saprotrophic fungi could be an efficient bioremediation strategy for PAH contaminated soils, but information about their compatibility is missing. In a greenhouse pot experiment we examined interactions between the AM fungus Rhizophagus irregularis and the saprotrophic fungus Trichoderma viride and their single and dual effects on maize plant growth perfonnance and communities of rhizosphere microorganisms in a Phenanthrene spiked soil. Phenanthrene reduced maize plant growth independent of both fungal inoculants, which were also both inhibited by Phenanthrene. On the other hand strong mutual inhibition between R. irregularis and T.viride was observed, which mitigated their plant growth promoting effects independent of Phenanthrene. In conclusion, the observed mutual inhibition between R. ireegularis and T. viride underline the importance of testing for compatibility between microbial inoculants when these are used in combination.

DOI: -

UT (Unique WOS ID): WOS:000450917100008

A catechol oxidase AcPPO from cherimoya (Annona cherimola Mill.) is localized to the Golgi apparatus

Author Full Names: Olmedo, Patricio; Moreno, Adrian A.; Sanhueza, Dayan; Balic, Ivan; Silva-Sanzana, Christian; Zepeda, Baltasar; Verdonk, Julian C.; Arriagada, Cesar; Meneses, Claudio; Campos-Vargas, Reinaldo


Cherimoya (Annona cherimola) is an exotic fruit with attractive organoleptic characteristics. However, it is highly perishable and susceptible to postharvest browning. In fresh fruit, browning is primarily caused by the poly phenol oxidase (PPO) enzyme catalyzing the oxidation of o-diphenols to quinones, which polymerize to form brown melanin pigment. There is no consensus in the literature regarding a specific role of PPO, and its sub cellular localization in different plant species is mainly described within plastids. The present work determined the subcellular localization of a PPO protein from cherimoya (AcPPO). The obtained results revealed that the AcPPO-green fluorescent protein co-localized with a Golgi apparatus marker, and AcPPO activity was present in Golgi apparatus-enriched fractions. Likewise, transient expression assays revealed that AcPPO remained active in Golgi apparatus-enriched fractions obtained from tobacco leaves. These results suggest a putative function of AcPPO in the Golgi apparatus of cherimoya, providing new perspectives on PPO functionality in the secretory pathway, its effects on cherimoya physiology, and the evolution of this enzyme.

DOI: 10.1016/j.plantsci.2017.10.012

UT (Unique WOS ID): WOS:000423003300006

Short-term response of soil microorganisms, nutrients and plant recovery in fire-affected Araucaria araucana forests

Author Full Names: Fuentes-Ramirez, Andres; Barrientos, Marcia; Almonacid, Leonardo; Arriagada-Escamilla, Cesar; Salas-Eljatib, Christian


Soil contains a wide variety of microorganisms that are responsible for fundamental ecological processes. However, increased frequency and severity of fires reduce microbial diversity and alter soil nutrient availability, affecting vegetation recovery. By using a large-scale wildfire that burned endangered Araucaria araucana forests in south-central Chile (38 degrees S), we assessed the short-term post-fire response of microorganisms, soil nutrients, and plant recovery. One year after fire, we sampled soils from burned and unburned areas, and measured the number of bacterial and fungal colony forming units, and the microbiological activity of the soil. We also measured soil nutrients (N, P, and K), organic matter content and species richness, abundance and plant diversity after fire. We found a significant increase in microbiological activity in burned soils (BS) compared to unburned soils (UBS), with bacteria and fungi being four and seven times greater in BS than in UBS, respectively. Concentrations of N, P and K were also greater in BS than in UBS. Plant species richness was two times higher in unburned than in burned areas, with a drastic reduction of the dominant tree species Araucaria araucana and Nothofagus pumilio after fire. The changes in soil properties after fire may be related to organic matter mineralization, the contribution of nutrients from ashes, or due to post-fire conditions (e.g., increased soil temperature after canopy removal by fire). Overall, our study shows a positive, short-term response in soil microorganisms abundance and nutrient content, but a rapid initial reduction of plant diversity of the main dominant tree species in these forest ecosystems after a severe fire. Further research is necessary as vegetation results are only preliminary and they can vary in the short-to-medium term. Our study provides insightful clues to delve into more applied research aimed at the post-fire restoration of the endemic, long-lived Araucaria araucana forests.

DOI: 10.1016/j.apsoil.2018.08.010

UT (Unique WOS ID): WOS:000444567700011