Search Results (114)

Varroa destructor represents a major threat to honeybee colonies worldwide, prompting the search for alternative organic acaricides. This study evaluated the biological activity of essential oils extracted from three Patagonian wild plants—Adesmia boronioides, Dysphania multifida, and Senecio filaginoides—on both V. destructor and Apis mellifera. Chemical analysis revealed that A. boronioides oil was dominated by esquelenone (34.49%), D. multifida by ascaridole (34.87%), and S. filaginoides by α-pinene (40.87%). All essential oils exhibited acaricidal activity, with D. multifida showing the lowest LC₅₀ against V. destructor (1.1 µL/mL at 24 h). Toxicity assays on adult bees indicated that A. boronioides and D. multifida significantly reduced bee survival, whereas S. filaginoides did not appear to cause significant mortality (LC₅₀ = 139.5 µL/mL). Repellency tests for A. boronioides and D. multifida showed significant mite repellence. Larval assays revealed a high survival rate under S. filaginoides treatment (survival rate > 80.24%), in contrast to the reduced viability observed with the other oils. The high selectivity index of S. filaginoides underscores its potential as a selective and safe botanical acaricide. Moreover, its LC₅₀ decreased over time, suggesting a residual acaricidal effect. These findings support S. filaginoides as a promising candidate for sustainable V. destructor control. Full article

The endemic Patagonian conifer, Austrocedrus chilensis, is threatened by the pathogen Phytophthora austrocedri. This study presents the first histological and histochemical analysis of A. chilensis affected by this pathogen. We examined the stem tissues of naturally infected adult trees (over 30 years old) and artificially inoculated saplings (8–12 years old) to identify the pathogen’s colonization strategies and the tree’s histological responses. Using light and scanning electronic microscopy along with several histochemical techniques (Lugol, toluidine blue, vanillin-HCl, Phloroglucinol, Calcofluor white, and aniline blue), we found that P. austrocedri can grow in all active tissues, leading to cambium and parenchyma necrosis. The pathogen spreads through sieve cells and tracheids, moving to the adjacent cells via sieve plates and bordered pits and colonizing nearby parenchyma cells. We observed loss of starch in necrotic tissues. In contrast, starch accumulation and an increase in the number of polyphenolic cells occur in the healthy areas adjacent to the margins of the lesion, indicating a tree’s induced defense mechanisms. The tree’s responses include cambium reprogramming, which leads to the formation of traumatic resin ducts, alterations in cell shape and size, and the deposition of phenolic compounds. We analyze the tree responses and discuss their potential relationship with a methyl jasmonate-induced defense and a hypersensitive-like response. Full article

The fossil and molecular evidence suggests that the area of origin of the Hairy Armadillo Chaetophractus villosus was the central Pampas region of Argentina, with a current distribution that includes Bolivia, Paraguay and Chile. We studied the evolutionary history of peripheral individuals of C. villosus using phylogeographic approaches and potential distribution models for the Holocene. We sequenced a segment of the mitochondrial DNA control region in 22 individuals with a peripheral distribution that inhabit the western limit of its current distribution in Chile, which was compared with Argentine sequences of the central distribution. The results show that the peripheral individuals studied have less genetic polymorphism than populations in the central distribution. All Chilean sequences were grouped in the haplotype C, which is dominant in Patagonian populations of Argentina. The potential distribution model predicts that during the Holocene the areas in which the peripheral populations of Chilean C. villosus are currently distributed presented medium–high habitability conditions for the species. Our results are consistent with the center–periphery model, showing a decrease in genetic diversity in peripheral areas of the distribution of C. villosus. It is probable that the low genetic diversity of the peripheral population is related to recent population establishment by dispersion from adjacent Argentine Patagonian populations. Peripheral populations such as those studied can have small population sizes; however, they can remain stable and have high survival rates during climatic oscillations, acting as important relics for the conservation and evolutionary potential of the species. Full article

The extant Patagonian mara Dolichotis patagonum (Zimmermann, 1780) is a cursorial herbivorous rodent that is hare-like in appearance. Nowadays, it occurs in some ecoregions of Argentina (28 °S–50 °S) in lowland habitats, in semi-arid thorn-scrub, in open grasslands and in shrub–land steppe. In this research, we have studied a partially preserved skull (FCDPV-2758), referred to D. patagonum, from the Late Pleistocene (Sopas Formation) in northern Uruguay (Arapey Grande River, Salto Department). Body mass estimates and morphological analyses were performed including contemporary specimens of D. patagonum, the Chaco mara Dolichotis salinicola, and extinct dolichotine species. The body mass estimate using the regression method and geometric similarity suggested a 6–8 kg range for the studied specimen, which is consistent with D. patagonum (7–8 kg) and notably greater than D. salinicola (1–2.3 kg). A comparative analysis, including the extinct D. platycephala and material previously referred to D. major from southwestern Uruguay, suggests that the studied specimen falls within the variation of D. patagonum, differing in part from D. chapalmalense and more clearly from D. salinicola, the extinct D. minor and Prodolichotis prisca. The implications of the wider geographic distributions of the living Patagonian mara at these latitudes in the Late Pleistocene in South America, and the paleoenvironmental significance are discussed. Full article

Artisanal fisheries in southern Chile rely heavily on the Patagonian red octopus (Enteroctopus megalocyathus) as a valuable resource, contributing significantly to local economies. This octopus species accounts for 25–40% of Chilean octopus landings. It is a merobenthic species, characterized by a semelparous life cycle and a long brooding period, and it is distributed along the Pacific and Atlantic coasts of the southern tip of South America, inhabiting holes and crevices in rocky substrates. However, this fishery faces critical challenges to both its ecological sustainability and the food safety of octopus products. The primary fishing method, using hooks, poses a risk to reproductive capacity as it can capture brooding females. Food safety concerns arise from microbial contamination during pre- and post-harvest handling, bioaccumulation of toxins from algal blooms, and the presence of heavy metals in the marine environment. While evisceration effectively reduces the risk of consuming toxins and heavy metals, inadequate hygiene practices and insufficient ice usage throughout the production chain represent significant food safety risks. Chilean fishing Law No. 18892/1989 defines artisanal fishing and establishes territorial use rights in fisheries (TURFs) to promote sustainable extraction of benthic resources. Integrating training programs on post-harvest handling, hygiene practices, and food safety measures into the TURFs framework, along with targeted investments in infrastructure and technical assistance, is crucial to ensure the long-term sustainability of the E. megalocyathus fishery, protect consumer health, and maintain the economic viability and environmental sustainability of this vital resource for local communities. Full article

Native forests provide forage for grazing animals. We investigated whether native and exotic vegetation promotes the potential animal load (PAL, ind ha⁻¹ yr⁻¹) for cattle (Bos taurus, ~700 kg) and sheep (Ovis aries, ~60 kg) in contrasting native forest types and canopy cover (closed, semi-open, open). This study was conducted in Chilean Patagonia (−44° to −49° SL). Vegetation cover (%) and growth habit data (trees, shrubs, forbs, graminoids, ferns, lianas, lichens, and bryophytes) were collected from 374 plots (>5 ha) in different environments: coihue (Nothofagus dombeyi, CO), lenga (N. pumilio, LE), mixed Nothofagus forests (MI), ñirre (N. antarctica, ÑI), evergreen forest (SV), and open land (OL). We combine this data with literature and laboratory analyses (e.g., crude protein, %) to develop PAL values for seasons. Data sampling was evaluated using descriptive analyses and uni- and multi-variate analyses (ANOVA, MCA, GLM). Results showed that closed forests had more native species (~56.6%) compared to open forests (~33.3%), while OL had higher cover of exotic species (~68.6%). LE presented the highest native species cover (~58.0%) and ÑI presented the highest exotic species cover (~53.0%). Closed forests had fewer exotic species than semi-open and open forests, which supported higher cover of native plants (p < 0.01). Forbs were the dominant growth habit in closed forests, while graminoids were dominant in OL (~45.8%). Multivariate analyses showed that LE and CO were associated with lower PAL values, explaining 91.2% variance. GLMs showed that the PAL increased in ÑI and the spring season, with forbs and graminoids having positive effects and shrubs and trees having negative effects (r² = 0.57–0.67). Our analyses also showed that exotic species dominated environment types with a high PAL, particularly during spring and summer, when cover increased. This indicates a trade-off between forage production in forests with exotic plants. Full article

We report the first case of flower bud galls in a species of the mainly American genus Senega (Polygalaceae), specifically in the South Andean Patagonian plant species S. salasiana. The galls were found to be induced by gall midges (Diptera, Cecidomyiidae) and mites (Acari). We also assessed their impact on plant reproduction by measuring the relationship between inflorescence density (number of inflorescences/plant cover) and gall abundance in two populations next to San Carlos de Bariloche, Patagonia, Argentina. Plant reproduction was negatively related to the number of galled inflorescences, suggesting that high levels of gall abundance strongly reduced plant reproductive success. Our study illustrates a novel case of flower galls in the genus Senega and highlights the negative impact of this type of herbivory on plant fitness. Full article

The invasion of exotic plants threatens biodiversity, affecting ecosystem services and ecological processes in native ecosystems. Road construction creates new environments and contributes to the introduction and spread of exotic and invasive plants. This study aimed to evaluate the representation of different functional groups (annual/biannual herbs and grasses, perennial herbs and grasses, shrubs, trees) in the invasion of exotic species within the assemblage on roadside slopes in the Austrocedrus chilensis forest in northwest Andean Patagonia, Argentina. Roadside slopes (RS) and nearby reference areas (RA) were selected, and the cover of native, exotic, and invasive species from the functional groups was evaluated in 1 m² plots using the Braun-Blanquet method. It was found that invasive perennial herbs and grasses predominated on RS, with a cover (19.6 ± 3.0%) higher than that of RA (8.9 ± 1.5%). Agrostis capillaris and Rumex acetosella were the most abundant invasive species. Native shrubs and perennial herbs and grasses were predominant on RS, with Baccharis rhomboidalis and Acaena pinnatifida being the most abundant. This study demonstrates that the roadside slopes of the Austrocedrus chilensis forest harbor invasive exotic species that can invade nearby natural areas. Early detection of these species is important for proper management and control, thus promoting the conservation of biodiversity in forest environments. Full article

Fisheries and aquaculture play a crucial role in global food security, yet species mislabeling remains a persistent challenge, undermining consumer trust and market transparency. Proper food labeling is essential for protecting public health due to the presence of unknown toxic or allergenic substances and preventing illegally sourced products from entering the market. Despite extensive research across Europe, seafood mislabeling in Croatia has remained unexplored. This study aims to provide the first comprehensive assessment of seafood labeling accuracy in Croatia, where fisheries are integral to the coastal economies and tourism. Using DNA barcoding of the COI gene, 109 seafood samples were collected over two years from various sources, including restaurants, markets, and fishing vessels, and analyzed for potential mislabeling. Results revealed a mislabeling rate of 3% among fish samples and 20% among cephalopods, with notable substitutions, such as the yellowfin tuna mislabeled as bigeye tuna and Bluefin tuna and the European squid mislabeled as Patagonian squid. Additionally, 38.5% of samples were partially labeled, while 32% lacked clear country-of-origin information, complicating traceability. While the findings align with the mislabeling rates in other European countries, this study underscores the ongoing challenges in seafood labeling compliance. Establishing standardized monitoring protocols will be essential for improving comparability and effectively addressing seafood fraud. Full article

Rangelands play a crucial socioeconomic and environmental role worldwide. In South America, desertification and overgrazing has led to their deterioration and declining productivity. Breeding programs that use native forage species of economic and ecological importance, such as Festuca pallescens (St. Yves) Parodi, may provide locally adapted germplasm that enhances productivity without threatening local biodiversity. These programs may even promote the conservation of native species. To this end, we characterized the phenotypic variation of nondestructive variables (growth and reproductive traits) related to forage and seed production during spring and early summer (growth and reproductive periods). Plants from ten populations were grown under common garden conditions in two environmental settings (sites) over two years. By early summer of the second year, most populations maintained a consistent relative performance with higher values for basal diameter, height and synflorescence production at site 2. This suggests more favorable environmental conditions for the species and highlights their potential for enhancing both seed and forage production. The growth and reproductive traits were probably largely influenced by micro-environmental cues (i.e., soil type and moisture), showing predominantly plastic patterns. The populations displaying phenotypic plasticity and above-average values for both traits were selected for further evaluation in breeding programs. Full article

The Argentine Patagonian region provides abundant plant-based materials for functional foods. This study evaluated the functional potential of tisanes made with black tea (BT) or rooibos (R) and Patagonian matrices (blueberry, rosehip, yacón), analyzing total phenols (TPs), flavonoids (Fvs), antioxidant activity (AA), sodium (Na), and potassium (K) content. Tisanes were prepared using 3 g/200 mL of water at 90 °C, with BT or R accounting for 40% of the dry mass and the remaining ingredients contributing 20% each. TPs (67 mg GAE/100 mL) and Fvs (35–42 mg/cup) contributed significantly to dietary intake. Sugar addition reduced bioactive compounds and AA, while sweeteners showed no significant impact. BT-based tisanes were low in sodium, while R-based tisanes had higher levels. Full article

Background: The cider industry is becoming an increasingly important segment of the apple fruit sector in Argentina. This study evaluated different inoculation strategies using two Patagonian strains to produce ciders with reduced malic acid and enhanced quality from acidic apple musts. Methods: Fermentations were performed using Pichia kudriavzevii NPCC1651 (isolated from cider) and Saccharomyces cerevisiae ÑIF8 (isolated from wine) in pure, simultaneous, and sequential inoculations. Viable cell counts, glucose and fructose consumption kinetics, and malic acid depletion were measured during fermentation, while physicochemical and aromatic profiles of the ciders were also analyzed in the final products. Results: P. kudriavzevii was capable of coexisting with S. cerevisiae until the final stages of fermentation, independently from the inoculation strategy employed. The simultaneous inoculation at a 1:1 ratio and the sequential inoculation initiated with S. cerevisiae showed the best performance. Both strategies produced ciders with high fermentative efficiency and elevated levels of lactic and succinic acids, isoamyl alcohol, 2-phenylethanol, isoamyl acetate, and 2-phenylethyl acetate while reducing acetic acid and ethyl acetate levels. These fermentations also achieved higher malic acid consumption compared to pure cultures. Conclusions: The simultaneous inoculation at a 1:1 ratio is proposed for further pilot-scale testing in natural acidic musts due to its operational practicality and its potential to produce ciders with reduced malic acid and improved sensory quality. Full article

Mesoscale eddies are known to influence the abundance and distribution of oceanic cephalopods. However, little is known about these effects in the southwest Atlantic Ocean. Therefore, this study analyzed the variations in environmental conditions and the resource abundance, spatial distribution, and habitat suitability of Illex argentinus within different life stages of cyclonic (CE) and anticyclonic (AE) eddies in Patagonian waters. From a comparison of squid abundance between CEs and AEs at each life stage, it was found that I. argentinus gradually increased in abundance after eddy formation, that abundance peaked during eddy maturation and that it subsequently decreased during the eddies’ decay phase. Spatially, squid resources in AEs were primarily concentrated in the northwest and southeast peripheral regions of the eddy, while in CEs, resources were more concentrated in the outer regions, on the western side of the eddy. Environmental factor analysis revealed that sea surface temperature (SST) and temperature at 200 m depth (T_200m) in both CEs and AEs reached their lowest values during the intensification and maturation phases of the eddies. Chlorophyll a (Chl-a) concentrations were significantly higher in CEs than in AEs from the formation to the maturation phase; however, during eddy decay, Chl-a concentrations were higher in AEs. According to a comparison of the suitability index (SI) for each environmental factor and the habitat suitability index (HSI) model, SI_SST, SI_T200m, and SI_Chl-a in AEs increased and then decreased with eddy evolution, with optimal SI values occurring during the intensification phase. In CEs, SI_SST and SI_T200m also increased and then decreased, with optimal SISST and SI_T200m occurring during the intensification and maturation phases, respectively, with little variation in SI_Chl-a across the life cycle of CEs. The HSI in both types of eddies gradually increased from the formation phase, reached a peak during maturation, and significantly decreased during eddy decay. Overall, this study indicated that habitat suitability and resource abundance for I. argentinus were highest during the maturation phase of the eddies. Full article

Over recent decades, Northern Patagonia in Chile has seen significant growth in agriculture, livestock, forestry, and aquaculture, disrupting lake ecosystems and threatening native species. These environmental changes offer a chance to explore how anthropization impacts zooplankton communities from a molecular–ecological perspective. This study assessed the anthropogenic impact on Daphnia pulex by comparing its proteomes from two lakes: Llanquihue (anthropized) and Icalma (oligotrophic). Results showed substantial differences in protein expression, with 17 proteins upregulated and 181 downregulated in Llanquihue, linked to elevated levels of copper, manganese, dissolved solids, phosphate, and nitrogen. These stressors caused metabolic damage and environmental stress in D. pulex. Our findings highlight the importance of monitoring pollution’s effects on Northern Patagonian ecosystems, especially on keystone species like D. pulex, essential for ecosystem stability. This research provides fresh molecular–ecological insights into pollution’s impacts, a perspective rarely addressed in this region. Understanding these effects is critical for conserving natural resources and offers pathways to study adaptive mechanisms in keystone species facing pollution. This approach also informs strategies for ecosystem management and restoration, addressing both immediate and long-term challenges in Northern Patagonian aquatic environments. Full article

Chile is a biodiverse region for deep-water skates (Rajiformes), with 36 species documented in national waters, of which 73% correspond to deep-water species. Among them, the Thickbody skate (Amblyraja frerichsi) and Whitemouth skate (Bathyraja schroederi) are two poorly documented species with relatively high abundances. However, the current information is limited to a few specimens reported over the last 50 years between southern Brazil (SW Atlantic) and central Chile (SE Pacific). In the Southeast Pacific, both species are bycatch in the Patagonian toothfish (Dissostichus eleginoides) fishery, which operates along the Chilean coast between 800 and 1600 m of depth. This study examined aspects of demography and reproductive biology based on data from 190 specimens (125 A. frerichsi and 65 B. schroederi) obtained from the fishery in northern Chile. The new data contribute to enhancing our understanding of deep-water skate communities and highlight the vulnerability and fishing pressure experienced across their geographic distribution. Full article