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Feijoa (Acca sellowiana), a native fruit tree of Brazil and Uruguay, has both a unique aroma and flavour. This species is widely cultivated in Colombia, New Zealand, and, to a lesser extent, in Georgia and Ukraine, amongst other countries. In its centre of diversity, Brazil and Uruguay, the cultivated area is increasing yearly. However, the occurrence of typical symptoms of anthracnose in feijoa plants has made fruit production difficult, or unfeasible, without the use of pesticides. Yet, little is known about the causal agent of anthracnose symptoms in feijoa fruit. Thus, this work aimed to analyse morphological and pathogenic characteristics of diseased fruit by using a multi-gene phylogenetic analysis based on DNA sequencing of six loci of 40 isolates in feijoa fruits collected in southern Brazil. Morphological data showed that mycelial radial growth rate ranged from 7.5 to 10.2 mm/day; length of conidia (L) ranged from 13.8 to 19.4 μm; width (W) ranged from 4.0 to 5.6 μm; and L/W ratio ranged from 2.5 to 4.2 μm. The size of appressoria ranged from 7.2 to 10.8 μm in length; 5.4 to 8.0 μm in width, and 1.1 to 1.5 μm for L/W. Isolates produced cylindrical or fusiform conidia and appressoria globules, nailed and irregular. Multigene phylogenetic analyses revealed the presence of anthracnose symptoms in both orchard-grown and natural populations of feijoa caused by Colletotrichum theobromicola assigned to the Gloeosporioides complex. All tested isolates showed that anthracnose symptoms caused pathogenicity in inoculated feijoa fruits. These results, together with data on lifestyle of the isolates, will lead to improved management and handling of commercial feijoa orchards. [ABSTRACT FROM AUTHOR]

Anthracnose (Elsinöe ampelina) is a major fungal disease in humid regions, causing damage to grapevine berries and decreasing fruit quality. Studies concerning enzymatic and biochemical changes caused by infection and tissue colonization of E. ampelina in berries are scarce, but they are fundamental to gaining insights about the defense response to the pathogen. Thus, this study aims to quantify biochemical and enzymatic alterations in different varieties of grapevine berries attacked by E. ampelina, and their association with anthracnose symptoms. Must quality, carbohydrate production, and enzymatic activity were assessed in berries with and without anthracnose symptoms, from five varieties that presented different degrees of anthracnose symptoms. Berries with anthracnose symptoms showed higher must acidity, while berries without anthracnose symptoms produced more proteins and higher polyphenol oxidase activity. The varieties manifesting the highest anthracnose symptoms showed higher sugar and hydrogen peroxide concentrations on berry skins. On the other hand, the varieties with the lowest anthracnose symptoms showed the highest catalase, polyphenol oxidase, and phenylalanine ammonia-lyase activities on berry skins. In conclusion, the varieties presented different severities of anthracnose on berries with higher anthracnose severities correlated with high hydrogen peroxide production and carbohydrate concentration on grape skins. [ABSTRACT FROM AUTHOR]

Key Message: Phylogenetic aspects, hotspots of nucleotide divergence, highly divergent genes, and specific RNA editing sites have been identified and characterized in the plastomes of the subgenus Passiflora. The genus Passiflora comprises more than 500 species across five subgenera: Astrophea, Decaloba, Deidamioides, Passiflora, and Tetrapathea. The most economically relevant species belong to the subgenus Passiflora, whose genetic pool and diversity among wild species remain poorly characterized. Similarly, little is known about the interspecific relationships within the subgenus Passiflora and the genetic causes of nuclear-cytoplasmic incompatibility observed in interspecific hybrids. Here, we report the complete nucleotide sequences of six plastomes belonging to species of the subgenus Passiflora, with the aim of better understanding the evolution of the plastome in this subgenus. Complete plastome sequences revealed five hotspots of nucleotide polymorphism: three intergenic regions and two coding sequences. Moreover, among 70 RNA editing sites predicted in our analysis for the subgenus Passiflora, 38 were not shared by all analyzed species, highlighting their species-specific occurrence. Furthermore, phylogenies based on plastid sequences accurately resolved most relationships between species and suggested a non-monophyletic origin of three super-sections of the subgenus Passiflora, previously defined solely based on morphological traits. Finally, our findings identified putative candidates, including predicted RNA editing sites and the coding sequences of accD and clpP genes, responsible for nuclear-cytoplasmic incompatibility in the interspecific hybrids of Passiflora. [ABSTRACT FROM AUTHOR]

The use of genetically modified (GM) plants has increased in recent decades, but there are uncertainties about their effects on soil microbial communities. Aiming to quantify root colonization and characterize arbuscular mycorrhizal fungi (AMF) communities associated with roots and rhizosphere soil of different maize genotypes, a field trial was carried out in Southern Brazil with three maize genotypes as follows: a GM hybrid (DKB 240 VTPRO), its non-modified isoline (DKB 240), and a landrace (Pixurum). Soil samples were collected to evaluate the occurrence of AMF during the growth of corn genotypes at sowing and V3 (vegetative), R1 (flowering), and R3 (grain formation) stages of the crop. The occurrence of AMF was determined by the morphological identification of spores, and by analyzing AMF community composition in soil and roots of maize, using PCR-DGGE. The GM genotype of maize promoted lower mycorrhizal colonization in the vegetative stage and had lower sporulation at grain development than the conventional hybrid and the landrace maize. Twenty AMF morphotypes were identified and 13 were associated with all maize genotypes. The genera Acaulospora, Glomus, and Dentiscutata had the largest numbers of species. There were no differences in AMF community composition due to maize genotypes or genetic modification, but crop phenological stages affected AMF communities associated with maize roots. [ABSTRACT FROM AUTHOR]

Background: World agricultural production of genetically modified (GM) products, in particular, the combination of different traits/genes in the same plant has been a trend over the last decade. There have been concerns raised over stacking multiple herbicide and insect-resistant transgenes that could result in fitness costs depending on the type and strength of selection pressures exerted by the environment. Here, we report the results of transcriptomic analysis comparing the effect of glyphosate-based herbicide (GBH) in the single-transgene versus stacked, herbicide-resistant soybean varieties on various biological processes, metabolic pathways, and key shikimic enzymes. Results: Gene expression data showed that defense metabolism and redox homeostasis were equally modulated in single-transgene and stacked-variety samples. Carbon accumulation and energy metabolisms were distinct between the varieties and photosynthesis metabolism was found negatively affected in the single-transgene variety only. In the stacked variety, the shikimate pathway was modulated by the accumulation of transcripts from phenylalanine gene and other cascade genes. As expected, the expression of native EPSPS was upregulated in both varieties when herbicide was applied. On the other hand, transgenic EPSPS expression was down-regulated in both GM varieties upon herbicide application which cannot be explained. Conclusion: Glyphosate-based herbicides toxicity suggests its effects on carbon central metabolism and flux, redox metabolism, photosynthesis, and to hormone and defense response in plants. The observed unintended effects in GM herbicide-tolerant varieties unravel the deleterious effects previously observed on GM-tolerant varieties growth and production. The impact of GBH on shikimate and cascade pathways was observed in terms of both native and transgenic insensitive EPSPS modulation, alteration of jasmonic acid and lignin metabolism in both single-transgene and stacked variety. The energy metabolism and carbon flux were differently affected in these varieties. Oxidative stress, more specifically glutathione metabolism, induced by GBH, was also observed in this study. The stacked variety showed a more pronounced stress response (activation of specific stress defense proteins, Rboh, WRKY) and secondary compounds (β-glucosidase, isoflavone 7-O-methyltransferase). Omics profiling techniques, such as transcriptomics, can be considered tools to support risk assessment in detecting unintended effects due to the GBH application. [ABSTRACT FROM AUTHOR]

Main conclusion: The plastome of B. orellana reveals specific evolutionary features, unique RNA editing sites, molecular markers and the position of Bixaceae within Malvales.Annatto (Bixa orellana L.) is a native species of tropical Americas with center of origin in Brazilian Amazonia. Its seeds accumulate the apocarotenoids, bixin and norbixin, which are only found in high content in this species. The seeds of B. orellana are commercially valued by the food industry because its dyes replace synthetic ones from the market due to potential carcinogenic risks. The increasing consumption of B. orellana seeds for dye extraction makes necessary the increase of productivity, which is possible accessing the genetic basis and searching for elite genotypes. The identification and characterization of molecular markers are essential to analyse the genetic diversity of natural populations and to establish suitable strategies for conservation, domestication, germplasm characterization and genetic breeding. Therefore, we sequenced and characterized in detail the plastome of B. orellana. The plastome of B. orellana is a circular DNA molecule of 159,708 bp with a typical quadripartite structure and 112 unique genes. Additionally, a total of 312 SSR loci were identified in the plastome of B. orellana. Moreover, we predicted in 23 genes a total of 57 RNA-editing sites of which 11 are unique for B. orellana. Furthermore, our plastid phylogenomic analyses, using the plastome sequences available in the plastid database belonging to species of order Malvales, indicate a closed relationship between Bixaceae and Malvaceae, which formed a sister group to Thymelaeaceae. Finally, our study provided useful data to be employed in several genetic and biotechnological approaches in B. orellana and related species of the family Bixaceae. [ABSTRACT FROM AUTHOR]

Recent review described that grape anthracnose in Brazil is caused by Elsinoe ampelina. However, in many countries, anthracnose can be associated with different species of Colletotrichum. A group of 20 isolates obtained from leaves and shoots of grapes genotypes showing typical anthracnose symptoms were characterized using morphological criteria, species-specific PCR and internal transcribed spacer (ITS) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) sequencing. Two morphological types (I and II) were identified on the basis of colony appearance and conidial shape. Type I (Colletotrichum acutatum complex) produced colonies of flat growth salmon concentric rings and short cylindrical conidia measuring 13 × 5.73 µm. Type II (C. gloeosporioides complex) produced cotton growth white colonies and cylindrical conidia with both ends rounded and the same size as in type I. Phylogenetic trees based on Bayesian inference and using combined ITS and GAPDH sequence alignment exhibited five main clades, which represented the species of C. acutatum (C. nymphaeae) and C. gloeosporioides (C. fructicola) complexes. The standard isolates of type I CB-a (C. nymphaeae) and type II CB-g (C. fructicola) were pathogenic to potted vines of the Niagara cultivar 1 week after inoculation. This is the first report of the occurrence of C. nymphaeae and C. fructicola associated with grape anthracnose symptoms in Santa Catarina State, southern Brazil. [ABSTRACT FROM AUTHOR]

Key message: The plastome of Linum usitatissimum was completely sequenced allowing analyses of evolution of genome structure, RNA editing sites, molecular markers, and indicating the position of Linaceae within Malpighiales. Abstract: Flax ( Linum usitatissimum L.) is an economically important crop used as food, feed, and industrial feedstock. It belongs to the Linaceae family, which is noted by high morphological and ecological diversity. Here, we reported the complete sequence of flax plastome, the first species within Linaceae family to have the plastome sequenced, assembled and characterized in detail. The plastome of flax is a circular DNA molecule of 156,721 bp with a typical quadripartite structure including two IRs of 31,990 bp separating the LSC of 81,767 bp and the SSC of 10,974 bp. It shows two expansion events from IRB to LSC and from IRB to SSC, and a contraction event in the IRA-LSC junction, which changed significantly the size and the gene content of LSC, SSC and IRs. We identified 109 unique genes and 2 pseudogenes ( rpl23 and ndhF). The plastome lost the conserved introns of clpP gene and the complete sequence of rps16 gene. The clpP, ycf1, and ycf2 genes show high nucleotide and aminoacid divergence, but they still possibly retain the functionality. Moreover, we also identified 176 SSRs, 20 tandem repeats, and 39 dispersed repeats. We predicted in 18 genes a total of 53 RNA editing sites of which 32 were not found before in other species. The phylogenetic inference based on 63 plastid protein-coding genes of 38 taxa supports three major clades within Malpighiales order. One of these clades has flax (Linaceae) sister to Chrysobalanaceae family, differing from earlier studies that included Linaceae into the euphorbioid clade. [ABSTRACT FROM AUTHOR]

In the past years the conservation of forest genetic resources has been widely recognized because of the risk of adverse effects associated with global changes in the environment. Since little effort has been made towards conservation of these resources, the assessment and the integration of information and knowledge so far generated are valuable tools in order to promote their conservation. In the present work the Brazilian conifer Araucaria angustifolia was used as a case study, integrating information, published between 1980 and 2007, about genetics, biotechnology, palaeobotany, and archeology. These studies were interpreted towards the conservation needs and strategies of the species germplasm. The main conclusions for the conservation of A. angustifolia genetic resources are: (1) despite the reduction of genetic diversity by unsustainable forest exploitation, the genetic system of A. angustifolia seems to be efficient to protect this species against rapid losses of its genetic diversity; (2) conservation measures starting now may be efficient, since the genetic structures of existing populations is more largely influenced by the past evolutionary process than by human disturbance occurred in the last century; (3) there are opportunities to save the genetic resources of the species, if simple measures are taken to safeguard the continued existence of the few remaining araucaria forests. Emerged as a general conclusion that the use of sound scientific arguments supported by different areas of the science could be a very powerful instrument in persuading decision-makers, also by governments, taking into account forest genetic resources as a primary issue for the future. [ABSTRACT FROM AUTHOR]

This paper investigates traditional knowledge of the use and management of Acca sellowiana in southern Brazil. Fifty-six informants from three rural communities were assigned to one of four subgroups ("maintainers," managers," "cultivators," or "users") based on their responses regarding management and use of A. sellowiana. Traditional knowledge related to use of this species is widespread among rural residents, but traditional knowledge related to management is fragmented depending on whether one uses, manages, or cultivates the species. Knowledge held in rural communities suggests that A. sellowiana could play an expanded role in local economies as well as biodiversity conservation. We suggest that participatory research could stimulate greater local use as well as on-farm conservation of A. sellowiana. [ABSTRACT FROM AUTHOR]

The use of microsatellite markers provides a window into the evolutionary processes of a given species. As such, these markers are widely used in scientific and applied research and are praised for their practicality and ease of use; however, the unavoidable incidence of genotyping deviations has been broadly neglected in the literature. Therefore, the present study aimed to estimate the rate of null alleles, mutations, and genotyping errors in microsatellite loci, using Araucaria angustifolia, a threatened species, as a case study. We estimated the rates of the different types of genotyping deviations using mother-progeny genotype comparison from 50 seed-trees and their respective progeny (seeds). A total of 2336 A. angustifolia samples were genotyped, and we found that the rate of null alleles was 0.045. From the 1972 mother-progeny comparisons, the overall genotype deviation rate was 1.58%, consisting of 145 inconsistences (mutations), 339 null alleles, and 210 genotyping errors. In terms of seed numbers, 128 (6.5%) showed inconsistencies in at least one locus, 118 (6.0%) null alleles, and 321 (16.3%) genotyping errors. This is the first study to describe the inconsistences (mutations) between mother-progeny genotypes for A. angustifolia, and the outcome makes it clear that an understanding of these genotyping deviations must be considered in assessing the accuracy of inferences made based on population genetics analyses. [ABSTRACT FROM AUTHOR]

Despite the high diversity of the Southern South American environments, the patterns and processes driving both their species diversity and demographic history are still poorly known and are a challenging task. In this study, we evaluate plastid DNA sequences of the conifer species Araucaria angustifolia aiming to (i) assess the species genetic structure within its main range of occurrence, (ii) infer its population demographic history, looking for evidence of southward expansion, (iii) search for evidence of glacial refugia within the species distribution area and (iv) discuss some conservation and management strategies for this species. Twenty haplotypes were identified, revealing the presence of three distinct genetic groups across the geographic range of the species and structuring the populations into Northern, Central and Southern groups. Our results suggest the occurrence of post-glacial expansion of A. angustifolia towards the south, as well as the existence of at least three refugia within the species occurrence area. Testing the occurrence of historical demographic expansion, we suggest that genetic groups experienced fluctuations in effective size, associated to a structured distribution of populations. The identification of three genetic groups in this study corroborates the proposition of using the geographic distribution of A. angustifolia for selecting in situ conservation areas, for planning seed collection for ex situ conservation, as well as for the delineation of seed zones. [ABSTRACT FROM AUTHOR]

Background: While some genetically modified organisms (GMOs) are created to produce new double-stranded RNA molecules (dsRNA), in others, such molecules may occur as an unintended effect of the genetic engineering process. Furthermore, GMOs might produce naturally occurring dsRNA molecules in higher or lower quantities than its non-transgenic counterpart. This study is the first to use high-throughput technology to characterize the miRNome of commercialized GM maize events and to investigate potential alterations in miRNA regulatory networks.Results: Thirteen different conserved miRNAs were found to be dys-regulated in GM samples. The insecticide Bt GM variety had the most distinct miRNome. These miRNAs target a range of endogenous transcripts, such as transcription factors and nucleic acid binding domains, which play key molecular functions in basic genetic regulation. In addition, we have identified 20 potential novel miRNAs with target transcripts involved in lipid metabolism in maize. isomiRs were also found in 96 conserved miRNAs sequences, as well as potential transgenic miRNA sequences, which both can be a source of potential off-target effects in the plant genome. We have also provided information on technical limitations and when to carry on additional in vivo experimental testing.Conclusions: These findings do not reveal hazards per se but show that robust and reproducible miRNA profiling technique can strengthen the assessment of risk by detecting any new intended and unintended dsRNA molecules, regardless of the outcome, at any stage of GMO development. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article in the 2011 issue regarding the risk assessment of the genetically modified (GM) bean production in Brazil.