The world's first glyphosate-resistant case of Avena fatua L. and Avena sterilis ssp. ludoviciana (Durieu) Gillet & Magne and alternative herbicide options for their control.

Avena fatua and A. ludoviciana (commonly known as wild oats) are the most problematic winter grass species in fallows and winter crops in the northeast region of Australia. A series of experiments were conducted to evaluate the performance of glyphosate and alternative post-emergence herbicides on A. fatua and A. ludoviciana. This study reports the world's first glyphosate-resistant (GR) biotypes of A. fatua and A. ludoviciana. The glyphosate dose required to kill 50% of the plants (LD50) and to reduce 50% of the biomass (GR50) for the GR biotype of A. fatua was 556 g a.e./ha and 351 g a.e./ha, respectively. These values for A. ludoviciana were 848 g a.e./ha and 289 g a.e./ha. Regardless of the growth stage (3-4 or 6-7 leaf stages), clethodim (120 g a.i./ha), haloxyfop (78 g a.i./ha), pinoxaden (20 g a.i./ha), and propaquizafop (30 g a.i./ha) were the best alternative herbicide options for the control of A. fatua and A. ludoviciana. The efficacy of butroxydim (45 g a.i./ha), clodinafop (120 g a.i./ha), imazamox + imazapyr (36 g a.i./ha), and paraquat (600 g a.i./ha) reduced at the advanced growth stage. Glufosinate (750 g a.i./ha), flamprop (225 g a.i./ha), and pyroxsulam + halauxifen (20 g a.i./ha) did not provide effective control of Avena species. This study identified alternative herbicide options to manage GR biotypes of A. fatua and A. ludoviciana.

A universal karyotypic system for hexaploid and diploid Avena species brings oat cytogenetics into the genomics era.

BACKGROUND: The identification of chromosomes among Avena species have been studied by C-banding and in situ hybridization. However, the complicated results from several cytogenetic nomenclatures for identifying oat chromosomes are often contradictory. A universal karyotyping nomenclature system for precise chromosome identification and comparative evolutionary studies would be essential for genus Avena based on the recently released genome sequences of hexaploid and diploid Avena species. RESULTS: Tandem repetitive sequences were predicted and physically located on chromosomal regions of the released Avena sativa OT3098 genome assembly v1. Eight new oligonucleotide (oligo) probes for sequential fluorescence in situ hybridization (FISH) were designed and then applied for chromosome karyotyping on mitotic metaphase spreads of A. brevis, A. nuda, A. wiestii, A. ventricosa, A. fatua, and A. sativa species. We established a high-resolution standard karyotype of A. sativa based on the distinct FISH signals of multiple oligo probes. FISH painting with bulked oligos, based on wheat-barley collinear regions, was used to validate the linkage group assignment for individual A. sativa chromosomes. We integrated our new Oligo-FISH based karyotype system with earlier karyotype nomenclatures through sequential C-banding and FISH methods, then subsequently determined the precise breakage points of some chromosome translocations in A. sativa. CONCLUSIONS: This new universal chromosome identification system will be a powerful tool for describing the genetic diversity, chromosomal rearrangements and evolutionary relationships among Avena species by comparative cytogenetic and genomic approaches.

The Pros and Cons of Using Oat in a Gluten-Free Diet for Celiac Patients.

A therapeutic gluten-free diet often has nutritional limitations. Nutritional qualities such as high protein content, the presence of biologically active and beneficial substances (fiber, beta-glucans, polyunsaturated fatty acids, essential amino acids, antioxidants, vitamins, and minerals), and tolerance by the majority of celiac patients make oat popular for use in gluten-free diet. The health risk of long-time consumption of oat by celiac patients is a matter of debate. The introduction of oat into the diet is only recommended for celiac patients in remission. Furthermore, not every variety of oat is also appropriate for a gluten-free diet. The risk of sensitization and an adverse immunologically mediated reaction is a real threat in some celiac patients. Several unsolved issues still exist which include the following: (1) determination of the susceptibility markers for the subgroup of celiac patients who are at risk because they do not tolerate dietary oat, (2) identification of suitable varieties of oat and estimating the safe dose of oat for the diet, and (3) optimization of methods for detecting the gliadin contamination in raw oat used in a gluten-free diet.

Volatile Profiles from Traditional Chinese Oat Meal Varied Significantly from Oat Porridge and Differed with Cultivars and Locations.

Volatile profiles of oat-based foods are mainly analyzed on the oat flakes and porridge as snack or breakfast, whereas the volatile characteristics of the traditional Chinese oat meal (TCOM), a popular main food in some regions of northern China, with special strong aroma, are not known. Here, we compared the volatile profiles from headspace solid phase microextraction gas chromatography-mass spectrometry analysis of oat porridge (OP) and TCOM, which were of different processing and cooking methods, from those of different cultivars, and analyzed the effect of cultivation locations on oat volatile features. Apart from the 35 volatiles shared by OP and TCOM, there were 23 and 24 volatiles specific to OP and TCOM, respectively, with the later showing more toasting and frying-related volatiles due to the dry frying process of the grains before milling. Principle component analysis of the volatiles of OP and TCOM from 16 cultivars showed that they were clustered into two groups, and four cultivars were clustered together, independent of processing and cooking methods. The oat volatile profiles of cultivars grown in three regions of north China were dependent on the cultivation locations rather than cultivars, regardless of OP or TCOM, with those from Datong of Shanxi Province and Zhangjiakou of Hebei Province clustered together. The location effect could be due to significant less precipitation in the two regions above than the other region Ulanqab of Inner Mongolia. PRACTICAL APPLICATION: The volatile compounds in oat are closely related to cultivation regions, which could be applied as a key factor by oat producers for marketing. The four cultivars showed similar and stable volatile profiles, which could be used as reference cultivars for breeding of high-quality oat with better flavor.

Naked Oat (Avena nuda L.) Oligopeptides:Immunomodulatory Effects on Innate and AdaptiveImmunity in Mice via Cytokine Secretion, AntibodyProduction, and Th Cells Stimulation.

The study aimed to investigate the immunomodulatory activity of oligopeptides derivedfrom oat (Avena Nuda L.) (OOPs). Healthy female BALB/c mice were randomly assigned to fivegroups, given deionized water (control) and 0.25, 0.5, 1.0, and 2.0 g/kg body weight (BW) of OOPsdaily by intragastric administration. Seven assays were performed to determine theimmunomodulatory effects of OOPs on immune organ ratios, cellular and humoral immuneresponses, macrophage phagocytosis, and natural killer (NK) cell activity. Spleen T lymphocytesubpopulations (by flow cytometry), serum cytokine and immunoglobulin levels (by multiplexsandwich immunoassays) were determined to evaluate how OOPs affected the immune system.Our results showed that OOPs could significantly improve innate and adaptive immune responsesin mice through the enhancement of cell-mediated and humoral immunity, macrophagephagocytosis capacity, and NK cell activity. We concluded that the immunomodulatory effectsmight be attributed to increased T and Th cell percentages, serum interferon (IFN)-γ, interleukin(IL)-1 α, IL-2, IL-6, IL-10, IL-12, tumor necrosis factor (TNF)- α, and granulocyte-macrophagecolony-stimulating factor (GM-CSF) secretions as well as immunoglobulin (Ig) A, IgG, and IgMproductions. These results indicate that dietary OOPs could be considered as promisingimmunomodulators with dosages ranging from 0.25 to 2.0 g/kg BW.

Identification and Quantification of Avenanthramides and Free and Bound Phenolic Acids in Eight Cultivars of Husked Oat ( Avena sativa L) from Finland.

Finland is the second largest oat producer in Europe. Despite the existing knowledge of phenolics in oat, there is little information on the phenolic composition of oats from Finland. The aim of the study was to investigate the concentrations of free and bound phenolic acids, as well as avenanthramides in eight Finnish cultivars of husked oat ( Avena sativa L.). Seven phenolic acids and one phenolic aldehyde were identified, including, in decreasing order of abundance: p-coumaric, ferulic, cinnamic, syringic, vanillic, 2,4-dihydroxybenzoic, and o-coumaric acids and syringaldehyde. Phenolic acids were mostly found as bound compounds. Significant varietal differences ( p < 0.05) were observed in the cumulative content of phenolic acids, with the lowest level found in cv. 'Viviana' (1202 ± 52.9 mg kg-1) and the highest in cv. 'Akseli' (1687 ± 80.2 mg kg-1). Avenanthramides (AVNs) 2a, 2p, and 2f were the most abundant. Total AVNs levels ranged from 26.7 ± 1.44 to 185 ± 12.5 mg kg-1 in cv. 'Avetron' and 'Viviana', respectively.

Genomic relationships among sixteen species of Avena based on (ACT)6 trinucleotide repeat FISH.

Knowledge of the locations of repeat elements could be very important in the assembly of genome sequences and their assignment to physical chromosomes. Genomic and species relationships among 16 species were investigated using fluorescence in situ hybridization (FISH) with the Am1 and (ACT)6 probes. The Am1 oligonucleotide probe was particularly enriched in the C genomes, whereas the (ACT)6 trinucleotide repeat probe showed a diverse distribution of hybridization patterns in the A, AB, C, AC, and ACD genomes but might not be present in the B and D genomes. The hybridization pattern of Avena sativa was very similar to that of A. insularis, indicating that this species most likely originated from A. insularis as a tetraploid ancestor. Although the two FISH probes failed to identify relationships of more species, this proof-of-concept approach opens the way to the use of FISH probes in assigning other signature elements from genomic sequence to physical chromosomes.

Assessment of Avenins from Different Oat Varieties Using R5-Based Sandwich ELISA.

Gluten derived from wheat and related triticeae cereals possesses distinct amino acid sequences that provoke the immunopathogenic features of celiac disease (CD) in genetically susceptible individuals. However, the role of oat-derived gluten, or avenins, in CD pathogenesis remains a disputed matter, as evidenced by a lack in harmonized legislation regarding gluten classification in relation to gluten-free labeling. In this study, we have analyzed a panel of pure oat cultivars using a sandwich ELISA based on the R5 monoclonal antibody (mAb), which binds to canonical epitopes occurring within celiagenic peptides present in triticeae-derived gluten but reportedly not present in avenins. We have identified three varieties of oats that reproducibly bind R5 antibodies and levels indicating the presence of gluten at more than the 20 ppm gluten regulatory threshold. Nested assessment using Western blot analysis and alternative gluten detection systems corroborated these results. Collectively, these data suggest that select oat varieties may prove problematic to patients with CD and to food companies and regulatory agencies and will extend our basic understanding of current gluten detection systems.

Wide Hybridization Between Oat and Pearl Millet.

Wide hybridization is a one of the important techniques in plant breeding. Oat (Avena sativa L.) and pearl millet (Pennisetum glaucum L.) belong to different subfamilies of Poaceae. In generally, such distant relative species show uniparental chromosome elimination after successful fertilization. However, all seven pearl millet chromosomes are retained beside the genome of oat during embryogenesis. Hybrid seedlings develop, but show necrosis after light irradiation. Here, a detailed protocol for wide hybridization between oat and pearl millet is described.

Promoting the Use of Common Oat Genetic Resources through Diversity Analysis and Core Collection Construction.

The assessment of diversity and population structure and construction of a core collection is beneficial for the efficient use and management of germplasm. A unique collection of common oat landraces, cultivated in the temperate climate of central Europe until the end of the twentieth century, is preserved in the Polish gene bank. It consists of 91 accessions that have never been used in breeding programs. In order to optimise the use of this genetic resource, we aimed to: (1) determine genetic and agro-morphological diversity, (2) identify internal genetic variation of the tested accessions, (3) form a core collection and (4) recognise the accessions useful for breeding programs or re-release for cultivation. The collection was screened using ISSR markers (1520 loci) and eight agro-morphological traits. Uniquely, we performed molecular studies based on 24 individuals of every accession instead of bulk samples. Therefore, assessment of the degree of diversity within each population and the identification of overlapping gene pools were possible. The observed internal diversity (Nei unbiased coefficient) was in the range of 0.17-0.31. Based on combined genetic and agro-morphological data, we established the core collection composed of 21 landraces. Due to valuable compositions of important traits, some accessions were also identified as useful for breeding programs. The population structure and principal coordinate analysis revealed two major clusters. Based on the previous results, the accessions classified within the smaller one were identified as obsolete varieties instead of landraces. Our results show that the oat landraces are, in general, resistant to local races of diseases, well adapted to local conditions and, in some cases, yielding at the level of modern varieties. Therefore, in situ conservation of the landraces in the near future may be satisfactory for both farmers and researchers in terms of the genetic resources preservation.

Use of Repetitive Sequences for Molecular and Cytogenetic Characterization of Avena Species from Portugal.

Genomic diversity of Portuguese accessions of Avena species--diploid A. strigosa and hexaploids A. sativa and A. sterilis--was evaluated through molecular and cytological analysis of 45S rDNA, and other repetitive sequences previously studied in cereal species--rye subtelomeric sequence (pSc200) and cereal centromeric sequence (CCS1). Additionally, retrotransposons and microsatellites targeting methodologies--IRAP (inter-retrotransposon amplified polymorphism) and REMAP (retrotransposon-microsatellite amplified polymorphism)--were performed. A very high homology was detected for ribosomal internal transcribed sequences (ITS1 and ITS2) between the species analyzed, although nucleolar organizing regions (NOR) fluorescent in situ hybridization (FISH) analysis revealed distinct number of Nor loci between diploid and hexaploid species. Moreover, morphological diversity, evidenced by FISH signals with different sizes, was observed between distinct accessions within each species. pSc200 sequences were for the first time isolated from Avena species but proven to be highly similar in all genotypes analyzed. The use of primers designed for CCS1 unraveled a sequence homologous to the Ty3/gypsy retrotransposon Cereba, that was mapped to centromeric regions of diploid and hexaploid species, being however restricted to the more related A and D haplomes. Retrotransposon-based methodologies disclosed species- and accessions-specific bands essential for the accurate discrimination of all genotypes studied. Centromeric, IRAP and REMAP profiles therefore allowed accurate assessment of inter and intraspecific variability, demonstrating the potential of these molecular markers on future oat breeding programs.

Genome size variation in the genus Avena.

Genome size is an indicator of evolutionary distance and a metric for genome characterization. Here, we report accurate estimates of genome size in 99 accessions from 26 species of Avena. We demonstrate that the average genome size of C genome diploid species (2C = 10.26 pg) is 15% larger than that of A genome species (2C = 8.95 pg), and that this difference likely accounts for a progression of size among tetraploid species, where AB < AC < CC (average 2C = 16.76, 18.60, and 21.78 pg, respectively). All accessions from three hexaploid species with the ACD genome configuration had similar genome sizes (average 2C = 25.74 pg). Genome size was mostly consistent within species and in general agreement with current information about evolutionary distance among species. Results also suggest that most of the polyploid species in Avena have experienced genome downsizing in relation to their diploid progenitors. Genome size measurements could provide additional quality control for species identification in germplasm collections, especially in cases where diploid and polyploid species have similar morphology.

Uptake and distribution of stable strontium in 26 cultivars of three crop species: oats, wheat, and barley for their potential use in phytoremediation.

The main objective of this study was to investigate the accumulation and distribution of strontium (Sr) in 26 cultivars of wheat (Triticum aestivum L.), husk oat (Avena sativa L) and naked oat (Avena nuda), and barley (Hordeum vulgare L.) for their potential use in phytoremediation.Sr levels had no effect on the accumulation of shoot biomass at tillering or at maturity. Mean shoot Sr concentration of naked oat and barley at tillering was significantly (P<0.05) higher than that of wheat; Neimengkeyimai-1, a naked oat cultivar, had the highest Sr concentrations. At maturity, of four naked oat cultivars, Neimengkeyimai-1 had the highest Sr content at all measured Sr levels. Leaves had the highest Sr concentrations, followed by roots and straw, and then grain with the lowest. Mean enrichment coefficients from soil to shoots ranged from 0.521 to 1.343; the percentage of stable Sr removed from the soil to the shoots at harvest time was more than 1.4% after 120 days. Neimengkeyimai-1 could be used as a model for further research to find more effective cultivars; and naked oat plants could be selected for phytoremediation to clean up contaminated soil.

Diversity of oat varieties in eliciting the early inflammatory events in celiac disease.

PURPOSE: Celiac disease (CD) is an autoimmune enteropathy, triggered by dietary gluten. The only treatment is a strict gluten-free diet. Oats are included in the list of gluten-free ingredients by European Regulation, but the safety of oats in CD is still a matter of debate. The present study examined the capability of different oat cultivars of activating the gliadin-induced transglutaminase-2 (TG2)-dependent events in some in vitro models of CD. In addition, we compared this capability with the electrophoresis pattern of peptic-tryptic digests of the proteins of the oat cultivars. METHODS: K562(S) cells agglutination, transepithelial electrical resistance of T84-cell monolayers, intracellular levels of TG2 and phosphorylated form of protein 42-44 in T84 cells were the early gliadin-dependent events studied. RESULTS: The results showed that the Nave oat cultivar elicited these events, whereas Irina and Potenza varieties did not. The ability of a cultivar to activate the above-described events was associated with the electrophoretic pattern of oat proteins and their reactivity to anti-gliadin antibodies. CONCLUSION: We found significant differences among oat cultivars in eliciting the TG2-mediated events of CD inflammation. Therefore, the safety of an oat cultivar in CD might be screened in vitro by means of biochemical and biological assays, before starting a clinical trial to definitely assess its safety.

Alimentos integrais / Foods Integrals

Introdução: Alimento integral é aquele que não teve sua estrutura modificada no processo de industrialização e manteve as vitaminas, os minerais e as fibras. Objetivo: Verificar evidências do uso dos alimentos integrais na prevenção e tratamento de doenças. Métodos: Busca sistematizada da literatura, por meio de busca eletrônica de artigos que avaliem o uso de alimentos integrais na terapêutica médica. Resultados: Encontramos uma revisão sistemática com 10 estudos com pouca qualidade metodológica e de curta duração. Esse estudo evidenciou uma diminuição significativa do colesterol total e do LDL-colesterol (lipoproteína de baixa densidade), sem influência na glicemia, peso corpóreo, pressão arterial e triglicérides, no grupo suplementado com alimentos integrais. Encontramos um ensaio clínico randomizado com 18 meses de acompanhamento, no qual o grupo que ingeriu alimentos integrais teve perda de peso com diminuição significativa da circunferência abdominal, sem perda significativa de vitaminas, minerais e fibras. Conclusão: Pelos estudos apresentados, os efeitos redutores do colesterol e do LDL-colesterol estão demonstrados em estudos de curta duração. Há necessidade de mais estudos com boa qualidade metodológica para verificarmos em longo prazo todas as alterações metabólicas e consequentes benefícios circulatórios.

In vitro antioxidant capacity and anti-inflammatory activity of seven common oats.

Oats are gaining increasing scientific and public interest for their purported antioxidant-associated health benefits. Most reported studies focused on specific oat extracts or particular oat components, such as ß-glucans, tocols (vitamin E), or avenanthramides. Studies on whole oats with respect to antioxidant and anti-inflammatory activities are still lacking. Here the antioxidant and anti-inflammatory activities from whole oat groats of seven common varieties were evaluated. All oat varieties had very similar oxygen radical absorption capacity compared with other whole grains. In an anti-inflammatory assay, oat variety CDC Dancer inhibited tumor necrosis factor-α induced nuclear factor-kappa B activation by 27.5% at 2 mg/ml, whereas variety Deiter showed 13.7% inhibition at a comparable dose. Avenanthramide levels did not correlate with the observed antioxidant and anti-inflammatory activities. Further investigations are needed to pinpoint the specific antioxidant and anti-inflammatory compounds, and potential synergistic and/or matrix effects that may help explain the mechanisms of oat's anti-inflammatory actions.

Classification of oat and groat kernels using NIR hyperspectral imaging.

An innovative procedure to classify oat and groat kernels based on coupling hyperspectral imaging (HSI) in the near infrared (NIR) range (1006-1650 nm) and chemometrics was designed, developed and validated. According to market requirements, the amount of groat, that is the hull-less oat kernels, is one of the most important quality characteristics of oats. Hyperspectral images of oat and groat samples have been acquired by using a NIR spectral camera (Specim, Finland) and the resulting data hypercubes were analyzed applying Principal Component Analysis (PCA) for exploratory purposes and Partial Least Squares-Discriminant Analysis (PLS-DA) to build the classification models to discriminate the two kernel typologies. Results showed that it is possible to accurately recognize oat and groat single kernels by HSI (prediction accuracy was almost 100%). The study demonstrated also that good classification results could be obtained using only three wavelengths (1132, 1195 and 1608 nm), selected by means of a bootstrap-VIP procedure, allowing to speed up the classification processing for industrial applications. The developed objective and non-destructive method based on HSI can be utilized for quality control purposes and/or for the definition of innovative sorting logics of oat grains.

Characterization of oats (Avena sativa L.) cultivars using machine vision.

Machine vision or image analysis is an important tool in the study of morphology of any materials. This technique has been used successfully to differentiate the eleven oats cultivars based on morphological characters. The geometry of seeds was measured through image analyzer and the variation was observed and recorded. From the recorded data, the cluster analysis was carried out and it revealed that the cultivars could be grouped into two main clusters based on similarity in the measured parameters. Cultivar Sabzar, UPO 212, OL 9 and OL 88 formed one main cluster. The another main cluster includes cv. Kent, OS 6, UPO 94, HFO 114, OS 7, HJ 8 and JHO 822 with many sub clusters. Among the cultivars HJ 8 and JHO 822 has more similarity in all measured parameters than other cultivars. Thus morphological characterization through seed image analysis was found useful to discriminate the cultivars.

Study on the sensitivity of three oat varieties to the saddle gall midge, haplodiplosis margina ta (von Roser) (Diptera: cecidomyiidae).

The saddle gall midge, Haplodiplosis marginota (von Roser, 1840) is a univoltine pest of cereals which occurs in Europe. The larvae feed on stems and attractive saddle-shaped depressions, driving to important yield losses when the galls are numerous. After 40 years without any reporting, large populations of H. marginata and important damage have been observed since 2010 in wheat crops in Belgium, especially in the Flemish Polders where clay soils and intensive farming of cereals favour heavy infestations. According to some research conducted in the 1960s during the last outbreak, oat (Avena sativa L.) is known to be one of the less favourable hosts to the saddle gall midge. Our study was performed in order to assess the host sensitivity of three oat varieties currently grown in Belgium: EVITA, EFFEKTIv and FREDDY. Therefore, oat varieties were sown on infested soil in two separate enclosures in a glasshouse. In the first enclosure, only the three oat varieties were grown; in the second one, these three oat varieties were grown together with two varieties of spring wheat: GRANNY and KWS CHAMSIN. TWO parameters were measured: the percentage of leaves with laid eggs, and the number of galls per stem. The percentage of leaves with eggs showed that the infestation was significantly lower on oats when they were in presence of wheat. The egg infestation was also significantly higher on wheat than on oat, which means oat is a much less favourable host plant than spring wheat for egg laying. Oat varieties were significantly different from each other regarding the number of galls per stem, but with very little damage compared to wheat. The FREDDY variety even seemed to be completely resistant to saddle gall midge, as no galls were observed although there was a similar percentage of leaves with eggs for the three oat varieties. Cropping oat could thus contribute to reduce infestations of H. morginato.

Potencial de inóculo de fungos micorrízicos arbusculares em solo cultivado com aveia em Umuarama - PR / Infectivity potential of arbuscular my corrhizal fungi in soil cultivated with black oais in Umuarama - PR / Potencial inoculo de hongos micorrizas arbusculares en suelo cultivado con avena en Umuarana - PR

Os fungos micorrízicos arbusculares (FMAs) são importantes para a sobrevivência e desenvolvimento das plantas e podem ser influenciados pelo manejo do solo. O objetivo do estudo foi avaliar os efeitos do cultivo da aveia preta na atividade microbiana do solo por isso da respiração basal do solo (RBS), o teor de matéria orgânica do solo (MOS), a densidade de esporos, colonização radicular e o potencial de inóculo de FMAs em relação à mata ciliar adjacente localizada na Universidade Paranaense – UNIPAR, Campus II – Unidade de Umuarama – PR. O potencial de infectividade do solo por FMAs foi definido a partir do método do número mais provável (NMP). O cultivo de aveia preta diminuiu a RBS em 22% quando comparado com o solo da mata ciliar, provavelmente devido ao maior teor de MOS na mata. A densidade de esporos dos FMAs apresentou diferenças significativas (p < 0,01), variando de 7,74 a 10,53 esporos g–1 em solo na mata ciliar e aveia preta, respectivamente. A colonização radicular por FMAs foi significativamente maior (p < 0,02) na aveia preta (36%) do que na mata ciliar (26%). O potencial de inóculo de FMAs foi maior no solo cultivado com aveia preta (1,09 propágulos g–1 de solo) do que no solo de mata ciliar (0,36 propágulos g–1). O cultivo do solo com aveia preta e baixo pH do solo aumentou a densidade de esporos, colonização radicular e potencial de inoculo de FMAs.

Arbuscular mycorrhizal fungi (AMF) are important for the survival and development of plants and may be influenced by the soil management. The objective of the study was to evaluate the effects of soil cultivation with black oats on soil microbial activity, basal soil respiration (BSR), soil organic matter (SOM), spore density, root colonization and infectivity potential of AMF in relation to a nearby riparian forest located at Universidade Paranaense, Campus II, Umuarama – PR. The infectivity potential of the soil by AMF was defined by the most probable number method (MPN). Cultivation of black oats decreased BSR by 22% when compared with riparian forest, probably due to high SOM in the riparian forest. Mycorrhizal spore density had significant differences (p < 0.01) between sampled areas, 7.74 to 10.53 spores g–1 of soil cultivated by riparian forest and black oats, respectively. Mycorrhizal root colonization was significantly (p < 0.02) higher in back oats (36%) than in riparian forest (26%). The infectivity potential of the soil by AMF was higher for soil cultivated with black oats (1.09 propagules g–1 of soil) than riparian forest (0.36 propagules g–1 of soil). The soil cultivation with black oats and the low soil pH increased spore density, root colonization and infectivity potential of AMF.

Los hongos micorrizas arbusculares (HMA) son importantes para la supervivencia y desarrollo de las plantas y pueden ser influenciados por el manejo del suelo. El objetivo de este estudio fue evaluar los efectos del cultivo de avena negra en la actividad microbiana del suelo, por respiración basal del suelo (RBS), el contenido de materia orgánica del suelo (MOS), la densidad de esporas, colonización radicular y potencial de inoculo de HMAs en comparación con la mata ciliar adyacente ubicada en la Universidad Paranaense - UNIPAR, Campus II - Unidad Umuarama - PR. El potencial de inefectividad del suelo por HMA se ha definido a partir del método de número más probable (NMP). El cultivo de avena negra disminuyó la RBS en 22% en comparación con el suelo de la mata ciliar, probablemente debido al mayor contenido de MOS en la mata. La densidad de esporas de los HMAs presentó diferencias significativas (p <0,01), variando de 7,74 a 10,53 esporas g-1 en suelo de la mata ciliar y avena negra. La colonización radicular por HMAs fue significativamente mayor (p <0,02) en la avena negra (36%), en comparación con la mata ciliar (26%). El potencial de inoculo de HMAs fue mayor en el suelo cultivado con avena negra (1,09 propágulos g-1 del suelo), en comparación con 0,36 propágulos g-1 del suelo de la mata ciliar. El suelo cultivado con avena negra es bajo en pH, aumentando la densidad de esporas, colonización radicular y potencial de inoculo de HMAs.