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Human activities have altered the frequency and intensity of wildfires, which can have severe consequences on forest ecosystems. Organic amendments and transplantation of native species are suggested as successful restoration alternatives for burnt areas. Biosolids composts produced in the Andean Patagonian region of Argentina could be used for this purpose, but little is known about the effects of organic amendments on seedling growth of native species. The objective of this study was to evaluate the response of the native species Austrocedrus chilensis and Nothofagus obliqua the addition of compost and/or nitrogen fertilizer in a greenhouse experiment using a volcanic forest soil affected by fire. After 4 years, treatment effects on plant growth and soil characteristics depended on the species. The main effect of biosolids compost on soil fertility was a marked increase in the availability of P from the soils of the two species. N. obliqua biomass increased and changed architectural parameters in response to nitrogen fertilization, but did not show changes due to compost addition. On the other hand, A. chilensis did not respond to N fertilization, but increase its biomass with compost and fertilization. Possibly N addition favored the nutrients uptake, such as phosphorus, calcium and magnesium provided by the compost. [ABSTRACT FROM AUTHOR]

Non-systemic logging, cattle browsing and grazing with the site natural vegetation can modify tree covers in native forests and alter the quantity and quality of organic matter entering the soil and hence its overall quality. The objective of this study was to evaluate the effect of modifying tree covers by uncontrolled logging and grazing processes on soil quality, in a mature and unmanaged roble (Nothofagus obliqua (Mirb.) Blume) forest. Soil quality was evaluated under partly-closed (PC), partly-open (PO), and open (OP) forest covers, and two soil depths. The indicators used were soil organic C (SOC), potential net N mineralization (N-min), and nitrification (N-NO3), soil microbial respiration (SMR), microbial biomass C (MBC), soil aggregates, and light fraction (LF). At 0-5 cm soil depth SMR and MBC in PC cover was approximately 12% higher than in PO and OP covers. For the same soil depth N-min in PC cover was 68% and 95% higher than in PO and OP covers, respectively; and for N-NO3 PC cover was 45% higher than PO cover. OP tree cover presented a negative N-NO3 (immobilization). Dry weight for LF fraction in OP cover (labile OM) was 90% and 67% lower respect PC and PO covers, respectively (P < 0.05). The soil quality and the activity of its microbial processes were affected by alteration of tree cover, as well by the anthropic action of logging and extensive grazing, the soil in OP cover was the most affected. [ABSTRACT FROM AUTHOR]

Discriminant molecular markers are required for research on population genetics, as well as evolutionary studies involving identification of hybrids and parental species, or detection of the genome regions under selection. We provide a set of 27 transcriptomic microsatellite markers (SSRs) for South AmericanNothofagusspecies, derived from 73Nothofagus alpina (=N. nervosa)annotated unigenes. Rates of cross-amplification ranged from 22% to 37%. Genetic characterisation of 22 transcriptomic SSRs forN. alpinaandN. obliquareveals low genetic variability, due to the general occurrence of one major allele at each locus, and high specificity, with few alleles shared between species (14%). At inter-species level 95% of loci were discriminant, with a total G''st over loci of 0.9, indicating that alleles were mostly fixed for all loci in both species. At intra-species level the number of markers with significant differentiation was 2.5 times higher forN. obliquathan forN. alpinapopulations. Moreover, transcriptomic SSRs showed higher performance compared with published anonymous microsatellites isolated from genome sequences without annotation. This set of transcriptomic microsatellites will be useful to the scientific community working on conservation and evolutionary aspects ofNothofagusspecies. [ABSTRACT FROM PUBLISHER]

The objective of this research was to determine emission factors (EF) for particulate matter (PM 2.5 ), combustion gases and particle size distribution generated by the combustion of Eucalyptus globulus (EG), Nothofagus obliqua (NO), both hardwoods, and Pinus radiata (PR), softwood, using a controlled combustion chamber (3CE). Additionally, the contribution of the different emissions stages associated with the combustion of these wood samples was also determined. Combustion experiments were performed using shaving size dried wood (0% humidity). The emission samples were collected with a tedlar bag and sampling cartridges containing quartz fiber filters. High reproducibility was achieved between experiment repetitions (CV < 10%, n = 3). The EF for PM 2.5 was 1.06 g kg − 1 for EG, 1.33 g kg − 1 for NO, and 0.84 g kg − 1 for PR. Using a laser aerosol spectrometer (0.25–34 μm), the contribution of particle emissions (PM 2.5 ) in each stage of emission process (SEP) was sampled in real time. Particle size of 0.265 μm were predominant during all stages, and the percentages emitted were PR (33%), EG (29%), and NO (21%). The distributions of EF for PM 2.5 in pre-ignition, flame and smoldering stage varied from predominance of the flame stage for PR (77%) to predominance of the smoldering stage for NO (60%). These results prove that flame phase is not the only stage contributing to emissions and on the contrary, pre-ignition and in especial post-combustion smoldering have also very significant contributions. This demonstrates that particle concentrations measured only in stationary state during flame stage may cause underestimation of emissions. [ABSTRACT FROM AUTHOR]

High inter-annual variations in flower and seed production have been frequently reported for wind-pollinated tree species. Such variations have been generally studied from a population perspective. The present study focuses on the meristematic cost of flower production in main branches of Nothofagus obliqua and N. nervosa through a retrospective analysis of flower production over 4-5 consecutive years. In both species, the percentage of flowering nodes in one year varied between 0 and 55 %. In N. obliqua, total flower production was bimodally distributed: years of high and low production were more common than years of intermediate production. Bimodality was not significant either for total flower production in N. nervosa or for each flower type separately in both species. Flower production affected branching negatively, which meant a meristematic cost. Periodicity in flower production was uneven among co-specific trees; more than two consecutive years of high flower production were rare in all trees. Inter-annual variations in the production of staminate and pistillate flowers were synchronized. In N. nervosa, the production of pistillate flowers tended to be more variable among years than the production of staminate flowers. The applied technique helps in the assessment of individual variations of flower production and contributes to understanding factors promoting seed-production variations in tree species at population scale. [ABSTRACT FROM AUTHOR]

Since 2009 extensive dieback and mortality of Nothofagus obliqua, associated with bleeding cankers on stems and branches, has been observed in the UK. The causal agent was identified as Phytophthora pseudosyringae, based on morphological and analysis of the internal transcribed spacer (ITS) sequences. Between 2011 and 2013, a survey assessed the frequency and nature of these P. pseudosyringae infections. Mature trees of Nothofagus with stem lesions caused by P. pseudosyringae were found across England, Scotland and Wales. Additional symptoms such as twig blight and leaf necrosis indicated that aerial infection was occurring. Besides N. obliqua, other hosts regularly encountered included Nothofagus alpina, Fagus sylvatica and Vaccinium myrtillus. In pathogenicity tests involving inoculation of logs, P. pseudosyringae was shown to be an aggressive bark pathogen of N. obliqua and F. sylvatica, but significantly less aggressive on N. alpina. Foliage susceptibility and sporulation tests showed marked differences between the six host species tested. Leaves of N. obliqua and V. myrtillus were highly susceptible. Leaves of N. alpina were moderately susceptible, those of Rhododendron ponticum slightly susceptible and those of F. sylvatica not susceptible at all. High levels of sporulation were observed only on inoculated N. obliqua and V. myrtillus leaves. This suggests that P. pseudosyringae may sporulate heavily on N. obliqua foliage in the field and that this inoculum initiates the aerial lesions observed on the shoots, branches and stems. The results also suggest that P. pseudosyringae has the potential to pose a serious threat to N. obliqua and other Nothofagus species in their Southern Hemisphere native ranges. [ABSTRACT FROM AUTHOR]

Hylamorpha elegans (Burmeister) is a native Chilean scarab beetle considered to be a relevant agricultural pest to pasture and cereal and small fruit crops. Because of their cryptic habits, control with conventional methods is difficult; therefore, alternative and environmentally friendly control strategies are highly desirable. The study of proteins that participate in the recognition of odorants, such as odorant-binding proteins (OBPs), offers interesting opportunities to identify new compounds with the potential to modify pest behavior and computational screening of compounds, which is commonly used in drug discovery, may help to accelerate the discovery of new semiochemicals. Here, we report the discovery of four OBPs in H. elegans as well as six new volatiles released by its native host Nothofagus obliqua (Mirbel). Molecular docking performed between OBPs and new and previously reported volatiles from N. obliqua revealed the best binding energy values for sesquiterpenic compounds. Despite remarkable divergence at the amino acid level, three of the four OBPs evaluated exhibited the best interaction energy for the same ligands. Molecular dynamics investigation reinforced the importance of sesquiterpenes, showing that hydrophobic residues of the OBPs interacted most frequently with the tested ligands, and binding free energy calculations demonstrated van der Waals and hydrophobic interactions to be the most important. Altogether, the results suggest that sesquiterpenes are interesting candidates for in vitro and in vivo assays to assess their potential application in pest management strategies. [ABSTRACT FROM AUTHOR]

Mortality of Nothofagus trees in the southern-central Chile region has been observed for over 30 years. A field survey conducted in 2013 detected partial defoliation and bleeding cankers on Nothofagus obliqua in a pure stand in the Nahuelbuta coastal ranges of the Biobío region. A Phytophthora sp. was isolated from stem cankers and soil samples around symptomatic N. obliqua trees: All isolates were identified as Phytophthora pseudosyringae. These isolates were pathogenic on 1-year-old N. obliqua and Nothofagus alpina, and on detached twigs of adult N. obliqua and Nothofagus dombeyi trees. This paper is the first to report association and pathogenicity of P. pseudosyringae with N. obliqua, N. alpina and N. dombeyi native to the Biobío region of Chile. The potential of P. pseudosyringae to cause damage in natural Nothofagus stands in Chile must be determined. [ABSTRACT FROM AUTHOR]

Using next-generation sequencing, we developed the first whole-genome resources for two hybridizing Nothofagus species of the Patagonian forests that crucially lack genomic data, despite their ecological and industrial value. A de novo assembly strategy combining base quality control and optimization of the putative chloroplast gene map yielded ~32 000 contigs from 43% of the reads produced. With 12.5% of assembled reads, we covered ~96% of the chloroplast genome and ~70% of the mitochondrial gene content, providing functional and structural annotations for 112 and 52 genes, respectively. Functional annotation was possible on 15% of the contigs, with ~1750 potentially novel nuclear genes identified for Nothofagus species. We estimated that the new resources (13.41 Mb in total) included ~4000 gene regions representing ~6.5% of the expected genic partition of the genome, the remaining contigs potentially being nongenic DNA. A high-quality single nucleotide polymorphisms resource was developed by comparing various filtering methods, and preliminary results indicate a strong conservation of cp DNA genomes in contrast to numerous exclusive nuclear polymorphisms in both species. Finally, we characterized 2274 potential simple sequence repeat ( SSR) loci, designed primers for 769 of them and validated nine of 29 loci in 42 individuals per species. Nothofagus obliqua had more alleles (4.89) on average than N. nervosa (2.89), 8 SSRs were efficient to discriminate species, and three were successfully transferred in three other Nothofagus species. These resources will greatly help for future inferences of demographic, adaptive and hybridizing events in Nothofagus species, and for conserving and managing natural populations. [ABSTRACT FROM AUTHOR]

The effect of glaciation on the levels and patterns of genetic variation has been well studied in the Northern Hemisphere. However, although glaciation has undoubtedly shaped the genetic structure of plants in the Southern Hemisphere, fewer studies have characterized the effect, and almost none of them using microsatellites. Particularly, complex patterns of genetic structure might be expected in areas such as the Andes, where both latitudinal and altitudinal glacial advance and retreat have molded modern plant communities. We therefore studied the population genetics of three closely related, hybridizing species of Nothofagus ( N. obliqua, N. alpina, and N. glauca, all of subgenus Lophozonia; Nothofagaceae) from Chile. To estimate population genetic parameters and infer the influence of the last ice age on the spatial and genetic distribution of these species, we examined and analyzed genetic variability at seven polymorphic microsatellite DNA loci in 640 individuals from 40 populations covering most of the ranges of these species in Chile. Populations showed no significant inbreeding and exhibited relatively high levels of genetic diversity ( HE = 0.502-0.662) and slight, but significant, genetic structure ( RST = 8.7-16.0%). However, in N. obliqua, the small amount of genetic structure was spatially organized into three well-defined latitudinal groups. Our data may also suggest some introgression of N. alpina genes into N. obliqua in the northern populations. These results allowed us to reconstruct the influence of the last ice age on the genetic structure of these species, suggesting several centers of genetic diversity for N. obliqua and N. alpina, in agreement with the multiple refugia hypothesis. [ABSTRACT FROM AUTHOR]

Abstract: This study describes the application of a multilocus sequence typing (MLST) analysis for molecular discrimination at the strain level of Spanish wine yeast strains. The discrimination power of MLST is compared to mitochondrial RFLP analysis. Fragments of the ADP1, ACC1, RPN2, GLN4, and ALA1 genes were amplified by PCR from chromosomal DNA of 18 wine Saccharomyces cerevisiae strains. Ten polymorphic sites were found in the five loci analyzed showing 13 different genotypes, with 11 of them represented by only one strain. RFLP analysis of the same 18 wine yeast strains showed seventeen different mitochondrial patterns. Phylogenetic relationships among the strains analyzed, inferred by MLST data, showed wine isolates of S. cerevisiae as a rather homogeneous group. The discrimination potential of mitochondrial RFLP analysis was superior to the MLST scheme used in this work. However, MLST analysis allowed an easy construction of reliable phylogenetic trees. MLST analysis offers the possibility of typing wine S. cerevisiae strains simultaneously to the study of the genetic relationship among them. [Copyright &y& Elsevier]

Abstract: Fourteen natural populations of the South-American Beech Nothofagus obliqua at the Eastern naturally fragmented area of its distribution range were subjected to genetic analysis using genetic markers. The genetic characterization of the analysed populations suggested probable distinct glacial origin of populations at North and South of the distribution. Furthermore, based on the allelic richness parameter, relict areas could be postulated within each of the identified latitudinal group. Natural hybridisation processes with the close related and sympatric species Nothofagus nervosa were also identified as one of the shaping forces modelling genetic variation patterns of the species. While ancient hybridisation was postulated for the northern watersheds, current hybridisation processes were suggested within the southern ones. Genetic isolation was identified as the main cause promoting the high genetic differentiation found among populations within watersheds. [Copyright &y& Elsevier]

Leaf litter decomposition experiments were conducted on two deciduous ( Nothofagus obliqua (roble)) and Nothofagus pumilio (lenga)) and one evergreen ( Nothofagus dombeyi) Nothofagus (Nothofagaceae) species from a single Chilean forest in order to understand how congeneric trees with differing leaf lifespans impact the soil in which they grow. Single-species litter samples were decomposed in a mixed hardwood forest in Ohio and in a deciduous-evergreen Nothofagus forest in Chile. In the Ohio forest, the two deciduous species’ litters decomposed at k ≈ 1.00 per year and the evergreen at k ≈ 0.75 per year. In Chile k ranged from k ≈ 0.06 ( N. obliqua) to k ≈ 0.23 ( N. pumilio) per year. In both experiments, N and P were released faster from the deciduous litters than from evergreen litter. In Ohio, evergreen litter immobilized more N and P for a longer time period than did deciduous litter. As N. dombeyi stands tend to have lower available soil N and P in this particular mixed Nothofagus forest, the increased time of N and P immobilization by N. dombeyi litter suggests a feedback role of the tree itself in perpetuating low N and P soil conditions. [ABSTRACT FROM AUTHOR]

In roots and mycorrhizae, the activity of phosphatases is an important parameter to characterise the efficiency of plants to access non-soluble phosphate pools in soils. We have quantified surface bound phosphatase (SBP) activity in non-mycorrhizal short roots and ectomycorrhizae of Nothofagus obliqua with image processed confocal laser scanning microscopy (LSM) using the fluorogenic substrate ELF-97 (enzyme-labelled fluorescence). Through interactive segmentation of root cells, mantle, and SBP-active centres, this method revealed a precise anatomical–physiological description of the SBP activity in cross-sections of short roots of N. obliqua, and of the mycorrhizal associations of N. obliqua with Pisolithus tinctorius and with Cenococcum geophilum in a controlled pH range (3–7).Our method revealed that the strategy of the examined species to vary the SBP activity was based primarily on the variation of the number and of the extension of the SBP-active centres. Fluctuations of the activities inside individual SBP-active centres were small. It was observed that non-mycorrhizal short roots of N. obliqua focus the distribution of SBP-active centres on the rhizodermis cells. In these cells, the SBP-active centres are distributed heterogeneously, and not preferentially in contact with the soil interface. The distribution of the SBP-active centres between the root cells and the mantle depended on the symbiont and on the pH of the buffer. The mantle hyphae of the N. obliqua–P. tinctorius associations promote direct contact between SBP-active centres and soil particles. In contrast, the mantle hyphae of N. obliqua–C. geophilum associations limit the expression of SBP-active centres to the interface between the mantle and the rhizodermis cells of N. obliqua. At this location, SBP-active centres are not in direct contact with any adjacent soil particles. Our observations of a pH-dependent activity, and of a mycorrhizal association-dependent activity of the SBP-active centres, together with the observed heterogeneity of the location of these centres relative to adjacent soil particles, challenge the general hypothesis that increased contact between mycorrhizae and soil results in higher efficiency of nutrient uptake. [Copyright &y& Elsevier]

Arguments in favour of usingNothofagus alpina(Poepp.&Endl.) Oerst. (Fagaceae) rather thanN. proceraOerst. orN. nervosa(Phil.) Krasser as the correct name for rauli are presented. We also refute suggestions thatN. alpinais based on hybrid material. The hybrid ofN. alpinawithN. obliqua(Mirb.) Blume is formally described asN. × dodecaphlepsMike L. Grant&E. J. Clement and a key to the deciduous taxa ofNothofagusis provided. © 2004 The Linnean Society of London,Botanical Journal of the Linnean Society, 2004,146, 447–451. [ABSTRACT FROM AUTHOR]

Nothofagus cunninghamii (myrtle) has a widespread distribution through the temperate rainforest of southeastern Australia with some disjunct populations existing in putative glacial refugia. Polymorphic nuclear markers are required to resolve the biogeographical history of the species and will also be useful for conservation and forestry applications in this and other species of Nothofagus. Fourteen polymorphic microsatellite loci were isolated from N. cunninghamii, with four to 10 alleles amplified in 15 individuals tested. Transferability to other species of Nothofagus was successful, with six loci transferring to all eight other species tested. [ABSTRACT FROM AUTHOR]