Caracterización estructural de un bosque pantanoso sin intervención antrópica en la comuna de Pitrufquén, Chile

Los bosques pantanosos de la zona Centro - Sur de Chile se distribuyen entre las regiones de Coquimbo a Los Lagos (30°- 41°28´ S). Destacan en la región de La Araucanía los bosques pantanosos denominados Pitrantos, dominados por Blepharocalyx cruckshanksii y Myrceugenia exsucca. Actualmente, los pitrantos se encuentran bajo el permanente estrés de las actividades antrópicas y podrían convertirse en ecosistemas extintos antes de ser científicamente conocidos. El objetivo de este trabajo es caracterizar estructuralmente un bosque pantanoso sin intervención antrópica en la comuna de Pitrufquén, Chile. Para esto, se estableció en el área de estudio una parcela rectangular de 300 m2 en donde se registró la especie arbórea, se midió la altura y el DAP de todos los individuos de tipo latizal, se contó el número de brinzales de cada especie y, finalmente, se contabilizó el número de plántulas en 50 subparcelas de 1 m2, distribuidas dentro de la misma parcela de muestreo. El bosque pantanoso establecido en el sitio de estudio se encuentra conformado por nueve especies arbóreas, todas latifoliadas, perennifolias y nativas; la más abundante Myrceugenia exsucca con 11.928 individuos por hectárea; seguida por Drimys winteri con 5.952 individuos y alturas totales máximas de 20 y 18 metros, respectivamente. Posee una estructura típica en cuanto a la altitud y longitud en donde se establece, y se encuentra regenerando con especies propias a una avanzada dinámica sucesional.

Phytochemistry and biological properties of Drimys winteriJR et G. Forster var chilensis(DC) A.

Drimys winteri JR et G. Forster var chilensis (DC) A. is a tree native to central and southern Chile. Also it found in part of Argentina. It is abundant in wet swampy localities from sea level to an altitude of 1700 m. This tree is sacred for the Mapuche culture; it is used in folk medicine in such as inflammatory and painful processes. Phytochemical studies have demonstrated that this plant contains mainly sesquiterpenes of the drimane type, flavonoids, essential oils, phytosterols and some lignans. These drimanes have attracted interest because of their antifeedant, plant growth regulation, cytotoxic, antimicrobial and insecticidal properties. The objective of this review is to establish clearly the phytochemistry and biological activity of Drimys winteri JR et G. Forster var chilensis (DC) A. Articles based on other varieties are not considered.

Trees, shrubs and herbs of the coastal Myrtaceae swamp forest (Región de La Araucanía, Chile): a dataset

Species lists are fundamental for knowledge of species diversity in regions subject to intense anthropogenic pressure, especially in poorly-studied ecosystems. The dataset comes from an inventory conducted in 30 fragments of Myrtaceae swamp forest, located in an agroforestry matrix landscape of the coastal La Araucanía Region in Chile. The data collection was carried out using line transect sampling, which was traced through the core of each fragment orientated towards its longest axis. The dataset provides a record of 55 species (24 trees, 1 vine [as a host], 16 herbs and 15 shrubs) including accidental epiphytes (n = 7), hemiparasites (n = 4), host (n = 10) and additionally woody debris (n = 36). The most frequent trees in the landscape were Myrceugenia exsucca (n = 36 records) and Blepharocalyx cruckshanksii (n = 33 records), species that were also the most common hosts. Drimys winteri was a companion species, other trees and shrubs generally being rarely observed, as was the case of the introduced species (Prunus avium, Rubus constrictus and Ulex europaeus). Branches were the most common microhabitat for hemiparasites. Within this group, Lepidoceras chilense was the most frequent species. For accidental epiphytes, Drimys winteri, which commonly grows on the ground (soil), were the most common species found in the main trunk crotch. Some unusual observations were the climber Cissus striata as host of Tristerix corymbosus (hemiparasite) and Tristerix corymbosus as host of Lepidoceras chilense (hemiparasite). This study represents a landscape-scale sample of the swamp forest, which is distributed in a dispersed pattern over a large stretch of Chile. The data were collected from 30 forest patches (from 0.05 to 936 ha), located on the coast of the Araucanía. The database includes the presence of 55 species of vascular plants in 356 records. The main novelty of this contribution is the systematic classification of species under six traits, never before reported in the same database: (i) condition (coarse woody debris, fallen log, live, snag), (ii) habit (herb, shrub, tree), (iii) growth microhabitat (e.g. tree trunk, branch, main trunk crotch), (iv) growth form (accidental epiphyte, hemiparasite, terricolous, vegetative), (v) host species (as appropriate) and (vi) relative location of the species in the sampled patch and surrounding areas (core, border, matrix). Species not previously observed in these forests were: Gavilea spp., Hieracium spp., Lophosoria quadripinnata, Berberis actinacantha, Gaultheria phillyreifolia, Ovidia pillo-pillo, Amomyrtus meli and Caldcluvia paniculata. In addition, two introduced species are novelties for the catalogue of vascular plants of Chile (Cupressus macrocarpa and Prunus avium). Several of these ecosystem traits are indeed new reports for these types of forests (e.g. accidental epiphytes, fallen logs, species-host relationship); at the same time, more frequent data (i.e. species composition, habit) are found in different contributions, making the comprehensive process of analysis difficult. Accordingly, the database is made available in this manuscript.

Antifungal Effects of Drimane Sesquiterpenoids Isolated from Drimys winteri against Gaeumannomyces graminis var. tritici

ABSTRACT Gaeumannomyces graminis var. tritici is a soilborne pathogen that causes “take-all” disease, affecting cereal roots. In wheat, G. graminis var. tritici is the most important biotic factor, causing around 30 to 50% losses of yield. Chemical control of this fungal disease is difficult because G. graminis var. tritici is able to reside for a long time in soils. Therefore, the development of environmentally friendly biotechnological strategies to diminish the incidence of soilborne diseases is highly desirable. Natural products are a promising strategy for biocontrol of plant pathogens. A special emphasis is on medicinal plants due to their reported fungitoxic effects. Drimys winteri (canelo) is a medicinal plant that is widely used by the Mapuche ethnic group from Chile due to its anti-inflammatory activity. In addition, inhibitory effects of canelo against phytopathogenic fungi and pest insects have been reported. In this study, we isolated, purified, and identified six drimane sesquiterpenoid compounds from canelo (drimenin, drimenol, polygodial, isodrimeninol, valdiviolide, and drimendiol). Then, we evaluated their antimicrobial effects against G. graminis var. tritici. Compounds were identified by comparing Fourier-transform infrared spectroscopy (FTIR) data and the retention time in thin-layer chromatography (TLC) with those of pure standards. The putative antagonistic effects were confirmed by assessing hyphal cell wall damage using confocal microscopy and lipid peroxidation. Here, we reported the high potential of drimane sesquiterpenoids as natural antifungals against G. graminis var. tritici. Polygodial and isodrimeninol were the most effective, with 50% lethal concentrations (LC50s) between 7 and 10 μg ml−1 and higher levels of fungal lipid peroxidation seen. Accordingly, natural sesquiterpenoids purified from canelo are biologically active against G. graminis var. tritici and could be used as natural biofungicides for sustainable agriculture. IMPORTANCE More than two billion tons of pesticides are used every year worldwide. An interesting sustainable alternative to control plant pathogens is the use of natural products obtained from plants, mainly medicinal plants that offer secondary metabolites important to human/animal health. In this study, we isolated and identified six pure drimane sesquiterpenoids obtained from the bark of Drimys winteri. Additionally, we evaluated their antifungal activities against Gaeumannomyces graminis (the main biotic factor affecting cereal production, especially wheat) by assessing fungal cell wall damage and lipid peroxidation. The compounds obtained showed important antifungal properties against G. graminis var. tritici, mainly isodrimenol, which was the second-most-active compound after polygodial, with an LC50 against G. graminis var. tritici of around 9.5 μg ml−1. This information could be useful for the development of new natural or hemisynthetic antifungal agents against soilborne phytopathogens that could be used in green agriculture.

Effect of different drying conditions on volatile compounds of Canelo pepper (Drimys winteri)

Canelo pepper is produced with the fruit of Drimys winteri (Winteraceae family). Driven by gourmet cuisine, this product is becoming increasingly in demand. The aim of this work was to study the effect of two drying conditions on the composition of the volatile compounds of Canelo pepper from Ushuaia forests (Argentina). Two treatments were evaluated. A mild drying (in a ventilated dryer, 2 days at 30 °C) that produced green pepper (G) and a strong drying (on an unventilated stove 6 days at 43 °C), which produced brown pepper (B). Untreated samples were used as fresh control (F). The profile of the volatile compounds of Canelo pepper varied when the fruits were dried and also changed with the drying conditions. Besides, the milder treatment affected the volatile compounds from the pepper to a lesser extent than the stronger drying.

Evaluation of Drimys winteri (Canelo) Essential Oil as Insecticide against Acanthoscelides obtectus (Coleoptera: Bruchidae) and Aegorhinus superciliosus (Coleoptera: Curculionidae)

Adverse effects caused by synthetic pesticides have increased interest in plant-derived insecticidal compounds, in particular essential oils, as a more compatible and ecofriendly alternative for pest control of economic importance. For this reason, the essential oil isolated from leaves and shoots of Drimys winteri (J.R. Forster & G. Forster)—also named canelo (CEO)—was investigated for its chemical profile and insecticidal action against Acanthoscelides obtectus (Say)—one of the most important post-harvest pests of dry beans in the world—and Aegorhinus superciliosus (Guérin)—a significant pest of fruit trees in Chile. The analysis by gas chromatography, paired with mass spectrometry (GC/MS) determined 56 compounds, corresponding to 92.28% of the detected compounds. Elemol (13.54%), γ-eudesmol (11.42%), β-eudesmol (8.49%), α-eudesmol (6.39%), α-pinene (7.92%) and β-pinene (5.17%) were the most abundant. Regarding the bioactivity of the CEO, the results demonstrated toxicological effects against A. obtectus. A concentration of 158.3 µL L−1 had a mortality rate of 94% after 24 h exposure. The LC50 and LC90 values at 24 h were 60.1 and 163.0 µL L−1. Moreover, behavioral bioassays showed a repellent effect against A. superciliosus with a dose of one microliter of CEO. Both sexes of the raspberry weevil stayed for very short times in the treated area with the oil (<0.8 min), showing a homogeneous repellency in the species. The overall data suggest that canelo leaves and shoots essential oil has an insecticide effect and is worth exploring to better understand the synergistic relationship between the compounds present in the essential oil.

Polyphasic studies of new species of Diaporthe from native forest in Chile, with descriptions of Diaporthe araucanorum sp. nov., Diaporthe foikelawen sp. nov. and Diaporthe patagonica sp. nov.

During a survey of fungi in native forests in Chile, several unidentified isolates of Diaporthe were collected from different hosts. The isolates were characterized based on DNA comparisons, morphology, culture characteristics and host affiliation, in accordance with previous descriptions. Phylogenetic analysis of the ITS region, combined with partial tub2 and tef1 genes, showed that the isolates formed three distinct groups representing three new taxa. The three new species of Diaporthe, Diaporthe araucanorum on Araucaria araucana, Diaporthe foikelawen on Drimys winteri and Diaporthe patagonica on Aristotelia chilensis are described and illustrated in the present study.