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Waterlogging stress frequently affects wheat production in the current conditions. The aim of this work was to evaluate the effect of waterlogging during grain filling on grain yield components, nitrogen uptake and partitioning and gluten composition and quality in bread wheat. Two greenhouse experiments were conducted under contrasting environmental conditions in Azul, Buenos Aires, in a completely randomized design with three replicates. The cultivar chosen was Klein León and the waterlogging treatment was imposed from 5 days after anthesis to maturity. The effects of waterlogging during grain filling in wheat depended on explored environmental conditions: early sowing vs. late sowing. Waterlogging had not significant effects on the most variables at early sowing conditions. However, the delaying in sowing date (higher temperature and radiation) enhance the effects of waterlogging: i) reducing grain weight by 41% and total nitrogen uptake by 51%; ii) reducing the ratio between the contents of high and low molecular weight glutenin subunits, affecting gluten composition; and iii) increasing the sodium dodecyl sulfate test from 79 to 108 mm, which correlates positively with the gluten strength. Reductions in grain weight due to waterlogging during grain filling affect the milling quality, although changes in protein composition may increase or maintain the gluten strength (SDSS) under particular conditions.

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Introduction

We investigated the main factors affecting the efficacy of protoplast isolation, including leaf-obtaining period, cutting shapes of leaf material, enzyme concentration, enzymolysis time, and centrifugal speed.

Methods

Protoplast isolation was optimal on the condition of 20 days of leaf materials, 2-mm filament of leaves, 1.6% RS and 0.8% R-10, 80 min of enzymolysis, and 700 rpm of centrifugation, resulting in the best yield (1.19 × 106 protoplasts/g FW) and vitality (80.34%) of mesophyll protoplasts. The transient expression vector pGFP1 with green fluorescent protein was transfected into the obtained protoplasts from castor by polyethylene glycol-mediated method with a transformation efficiency of 12.37%.

Results

Moreover, the applicability of the system for studying the subcellular localization of RcFATA (an acyl-ACP thioesterase) was validated via the protoplast isolation and transient expression protocol in this study.

Discussion

Collectively, the efficient mesophyll protoplast isolation and protoplast transient expression system facilitate to analyze the function of specific gene in castor (Ricinus communis L).

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Authors: Cheimâa Bouchekouk, Fatima Zohra Kara, Ghania Tail, Fairouz Saidi and Tarek Benabdelkader

Introduction

The present work aims to study the chemical composition of Pteridium aquilinum (L.) Kuhn essential oil and its antibacterial activity against three important phytopathogenic Gram-negative bacteria: Erwinia amylovora, Pectobacterium carotovorum subsp. carotovorum, and Pseudomonas savastanoi pv. savastanoi.

Methods

The chemical composition of P. aquilinum L. essential oil produced by hydrodistillation was determined by gas chromatography–mass spectrometry. The antibacterial activity was tested using disk diffusion method and by determination of minimum inhibitory concentration values. The major components were linalool (10.29%), carvacrol (8.15%), benzaldehyde (5.95%), 2-undecanone (5.32%), and cuminaldehyde (4.57%).

Results

The essential oil tested revealed a powerful antibacterial effect against all tested strains, with inhibition zone diameters ranging from 32.0 ± 0.58 to 33.7 ± 0.88 mm.

Discussion

P. aquilinum EO contained 32.86% of oxygenated monoterpenes, which are known for their very powerful antimicrobial activities. The minimum inhibitory concentration values showed that P. aquilinum essential oil has very strong activity against E. amylovora (0.625 μl/ml), followed by P. carotovorum subsp. carotovorum (2.50 μl/ml) and P. savastanoi pv. savastanoi (5.00 μl/ml). The results obtained could contribute to the development of new potential agents for the control of bacterial diseases.

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Intestinal carriage of multi-drug resistant (MDR) Gram-negative bacteria including Pseudomonas aeruginosa (Psae) constitutes a pivotal prerequisite for subsequent fatal endogenous infections in patients at risk. We here addressed whether fecal microbiota transplantation (FMT) could effectively combat MDR-Psae carriage. Therefore, secondary abiotic mice were challenged with MDR-Psae by gavage. One week later, mice were subjected to peroral FMT from either murine or human donors on 3 consecutive days. Irrespective of murine or human origin of fecal transplant, intestinal MDR-Psae loads decreased as early as 24 h after the initial FMT. Remarkably, the murine FMT could lower intestinal MDR-Psae burdens by approximately 4 log orders of magnitude within 1 week. In another intervention study, mice harboring a human gut microbiota were perorally challenged with MDR-Psae and subjected to murine FMT on 3 consecutive days, 1 week later. Strikingly, within 5 days, murine FMT resulted in lower loads and carrier rates of MDR-Psae in mice with a human gut microbiota. In conclusion, FMT might be a promising antibiotics-independent option to combat intestinal MDR-Psae carriage and thus prevent from future endogenous infections of patients at risk.

Open access
Authors: J.P. Sserumaga, D. Makumbi, M.L. Warburton, S.O. Opiyo, G. Asea, A. Muwonge and C.L. Kasozi

Insights into the diversity and relationships among elite breeding materials are an important component in maize improvement programs. We genotyped 63 inbred lines bred for high levels of provitamin A using 137 single nucleotide polymorphism markers. A total of 272 alleles were detected with gene diversity of 0.36. Average genetic distance was 0.36 with 56% of the pairs of lines having between 0.30 and 0.40. Eighty-six percent of the pairs of lines showed relative kinship values <0.50, which indicated that the majority of these provitamin A inbred lines were unique. Relationship pattern and population structure analysis revealed presence of seven major groups with good agreement with Neighbour Joining clustering and somewhat correlated with pedigree and breeding origin. Utilization of this set of provitamin A lines in a new biofortification program will be aided by information from both molecular-based grouping and pedigree analysis. The results should guide breeders in selecting parents for hybrid formation and testing as a short-term objective, and parents with diverse alleles for new breeding starts as a long-term objective in a provitamin A breeding program.

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Seed germination is a new beginning for the crop life cycle, which is closely related to seed sprouting and subsequent plant growth and development, and ultimately affects grain yield and quality. Salt stress is one of the most important abiotic stress factors that restrict crop production. Therefore, it is highly important to improve crop salt tolerance and sufficient utilization of saline-alkali land. In this study, we identified the phosphorylated proteins involved in salt stress response by combining SEM, 2-DE, Pro-Q Diamond staining and tandem mass spectrometry. The results showed that salt stress significantly inhibited seed germination and starch degradation. In total, 14 phosphorylated protein spots (11 unique proteins) in the embryo and 6 phosphorylated protein spots (4 unique proteins) in the endosperm were identified, which mainly involved in stress/defense, protein metabolism and energy metabolism. The phosphorylation of some proteins such as cold regulated proteins, 27K protein, EF-1β and superoxide dismutase could play important roles in salt stress tolerance.

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Authors: V. Greveniotis, S. Zotis, E. Sioki and C.G. Ipsilandis

The objectives of this study were (a) to compare the effectiveness of the two methods of pedigree selection in barley: the ear-to-row classical pedigree method and the honeycomb method and (b) the evaluation of the selection criteria of the honeycomb methodology. Five F12 lines developed by classical pedigree method were used as checks in order to compare seven lines developed by honeycomb methodology. Five honeycomb pedigree lines were selected by PYI basic selection criterion of honeycomb methodology and two more (rejected by PYI) were selected by YC, a new criterion proposed for improving selection of high yielding plants in honeycomb design. Also, the original local population from which all these lines were derived and two commercial barley cultivars were used as the basic checks. All genotypes selected by classical and honeycomb pedigree method out yielded the original local population. Many of them reached or out yielded the commercial cultivars used as checks and thus both classical and honeycomb pedigree methods were able to promote some homozygous genotypes in order to be used as new cultivars. Yield performance of progeny lines selected by classical pedigree method was better than honeycomb’s. Only when YC was used as selection criterion honeycomb pedigree lines showed high yielding performance. Comparing PYI and YC selection criteria, it seems that the second is better for promoting high yielding and stable lines for next generations to be used as future new cultivars. Grain yield and bulk density are safer traits than 1000-kernel weight, for efficient selection that ensures high and stable yields.

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Applying both molecular data and ecological niche modelling is essential to infer the speciation mechanism and species delimitation in organisms. Salvia aristata Auch. ex Benth is an endemic species restricted to western, northwestern and centre of Iran and eastern parts of Turkey with variations in morphological character along its distributions. In this study, we applied SRAP marker and ecological niche modelling using climatic and geographic data to detect and examine the genetic structure and niche differentiation in S. aristata accessions. SRAP marker’s results showed 242 bands highly polymorph. Genetic distance analysis provided two main clusters. The STRUCTURE analysis provided two distinct ecotypes (K = 2). Our ecological niche model produced good results with high performance based on area under curve (AUC > 0.9) for both ecotypes. Altitude was the most important variable contributing in niche model of both ecotypes. The niche space of both ecotypes is different based on niche identity test and background test as well. Based on genetic and ecological evidence, it is concluded that S. aristata gene pool underwent a parapatric speciation process caused by niche divergence and reproductive isolations as a consequence of divergent selection on floral traits.

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Introduction

It was previously shown that intracerebroventricular administration of pituitary adenylate cyclase-activating polypeptide (PACAP) prior to GnRH mobilization in proestrus prevents ovulation in rats. In this study, we examined whether PACAP given intranasally could influence luteinizing hormone (LH) and prolactin (PRL) surges and ovulation.

Methods

On the day of proestrus PACAP, β-cyclodextrin (modifier of blood–brain barrier) or PACAP + β-cyclodextrin was applied intranasally between 12:30 and 13:00. Blood samples were taken at 16:00, 18:00, and 20:00 for measuring plasma hormone levels. In the next morning, the expelled ova were counted. β-Cyclodextrin was also administered to male and diestrous female rats between 12:30 and 13:00 and blood was taken at 18:00.

Results

PACAP prevented LH and PRL surges and ovulation in about half of the rats, β-cyclodextrin alone more effectively prevented ovulation. When PACAP and β-cyclodextrin were administered together, more rats ovulated like when PACAP given alone. β-Cyclodextrin did not influence LH and PRL levels in diestrous females; however, in males, it significantly enhanced PRL level.

Discussion

Not only the intracerebroventricular, but the intranasal application of PACAP prevented ovulation. β-Cyclodextrin alone is more effective than PACAP and enhances PRL levels in male rats. PACAP and β-cyclodextrin given together weaken each other’s effect. β-Cyclodextrin, as excipient of various drugs, has to be used carefully in human medications.

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Mitotic chromosomes from root tips of four Nigerian Physalis species were investigated using standard cytogenetic methods. P. angulata has chromosome number of 2n = 48 with karyotypic formula of 2M + 5m + 16sm + 1st, while P. micrantha, P. peruviana and P. pubescens showed the same chromosome number of 2n = 24 with karyotypic formulae of 1M + 1m + 9sm + 1st, 4M + 6m + 1sm + 1st and 1M + 1 m + 2sm + 8st, respectively. The karyotypes show that P. angulata is more advanced when compared to the other three diploids studied.

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We present the results of lichenological survey in the area of Zemplínske vrchy Mts in this paper. The study area is underexplored regarding lichens and there are not many published resources on lichens. In total thirty-five localities were investigated and 68 lichen species were identified. Fifteen species of them are evaluated in the Red list of lichens of Slovakia. From interesting findings, Cladonia crispata, Graphis scripta, Lecanora conizaeoides and Flavoparmelia caperata are discussed here. Physcia leptalea is reported for the first time for the area of Slovakia.

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Authors: S.M. Pirseyedi, A. Kumar, F. Ghavami, J.B. Hegstad, M. Mergoum, M. Mazaheri, S.F. Kianian and E.M. Elias

Fusarium head blight (FHB) damage in durum wheat (Triticum turgidum L. var. durum Desf., turgidum) inflicted massive economic losses worldwide. Meanwhile, FHB resistant durum wheat germplasm is extremely limited. ‘Tunisian108’ is a newly identified tetraploid wheat with FHB resistance. However, genomic regions in ‘Tunisian108’ that significantly associated with FHB resistance are yet unclear. Therefore, a population of 171 backcross inbred lines (BC1F7) derived from a cross between ‘Tunisian108’ and a susceptible durum cultivar ‘Ben’ was characterized. Fusarium graminearum (R010, R1267, and R1322) was point inoculated (greenhouse) or spawn inoculated (field) in 2010 and 2011. Disease severity, Fusarium-damaged kernel (FDK) and mycotoxins were measured. Analysis of variance showed significant genotype and genotype by environment effect on all traits. Approximately 8% of the lines in field and 25% of the lines in greenhouse were more resistance than Tunisian108. A framework linkage map of 267 DArt plus 62 SSR markers was developed representing 239 unique loci and covering a total distance of 1887.6 cM. Composite interval mapping revealed nine QTL for FHB severity, four QTL for DON, and four QTL for FDK on seven chromosomes. Two novel QTL, Qfhb.ndsu-3BL and Qfhb.ndsu-2B, were identified for disease severity, explaining 11 and 6% of the phenotypic variation, respectively. Also, a QTL with large effect on severity and a QTL with negative effect on FDK on chromosome 5A were identified. Importantly, a novel region on chromosome 2B was identified with multiple FHB resistance. Validation on these QTL would facilitate the durum wheat resistance breeding.

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Authors: Souba Diandé, Gisèle Badoum, Adjima Combary, Issaka Zombra, Tandaogo Saouadogo, Léon T. Sawadogo, Bayéma Nébié, Saïdou Gnanou, Adama Zigani, Seydou Mohamed Ouédraogo, Adama Diallo, Seydou Kaboré and Lassana Sangaré

Setting: A survey of the prevalence of drug-resistant tuberculosis (DR-TB) in new and previously treated patients (PTPs) was performed in Burkina Faso from 2016 to 2017.

Design: In this cross-sectional survey, a structured questionnaire was administered to eligible smear-positive patients in all 86 diagnostic and treatment centers of the country to collect their socio-demographic characteristics and medical histories. Their sputa were tested using the Mycobacterium tuberculosis/rifampicin (MTB/RIF) Xpert assay. Those which were found to be positive for TB and rifampicin-resistant were also tested with GenoType MTBDRplus2.0 and MTBDRsl2.0. Univariate and multivariate logistic regressions were performed to determine risk factors associated with rifampicin resistance.

Results: Of the 1140 smear-positive patients enrolled, 995 new and 145 PTPs were positive for MTB complex by Xpert. Of these, 2.0% (20/995, 95% confidence interval (CI): 1.1–2.9) of the new cases and 14.5% (95% CI: 14.2–20.2) of the PTPs were resistant to rifampicin; 83% of them has multidrug-resistant tuberculosis (MDR-TB). None were pre-extensively drug-resistant TB (pre-XDR-TB) or XDR-TB. Only the previous treatment was significantly associated with rifampicin resistance, p < 0.0001.

Conclusion: Similar to global trends, rifampicin resistance was significantly higher in patients with prior TB treatment (14.5%) than in naïve patients (2.0%). These percentages are slightly below the global averages, but nonetheless suggest the need for continued vigilance. Extending the use of Xpert testing should strengthen the surveillance of DR-TB in Burkina Faso.

Open access
Authors: S. Y. Kondratyuk, J. P. Halda, L. Lőkös, Y. Yamamoto, L. P. Popova and J.-S. Hur

Six new for science species of lichen-forming fungi from Republic of Korea, Eastern Asia, i. e.: Bacidina jasonhuri J. P. Halda, S. Y. Kondr. et L. Lőkös, Gyalidea koreana J. P. Halda, S. Y. Kondr. L. Lőkös et Hur, G. pisutii J. P. Halda, S. Y. Kondr. L. Lőkös et Hur, G. poeltii S. Y. Kondr. L. Lőkös, J. P. Halda et Hur, G. Vězdae S. Y. Kondr. L. Lőkös, J. P. Halda et Hur, and Porpidia ulleungdoensis S. Y. Kond. L. Lőkös et J. P. Halda, as well as two new species from Japan (Fauriea yonaguniensis S. Y. Kondr. M. Moriguchi et Yoshik. Yamam. and Laundonia ryukyuensis S. Y. Kondr. M. Moriguchi et Yoshik. Yamam.), and one new species Lecanora orlovii S. Y. Kondr. et L. Lőkös from Ukraine are described, illustrated and compared with closely related taxa.

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Five species of lichenized ascomycetes are reported from high mountainous Dagestan. Acarospora laqueata, Lecania ochronigra and Protoparmelia placentiformis are new to Russia and the Caucasus (the last two). Anamylopsora pulcherrima is the first record of the genus and species for the North Caucasus. Buellia centralis is the first record for the Caucasus and second for Russia. Our records considerably extended information about geography and ecology of presented species especially the very rare species Buellia centralis, Lecania ochronigra and Protoparmelia placentiformis. The characteristic features of specimens with information of their morphology, anatomy, ecology and world distribution are given.

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The data on 31 species of lichenicolous fungi (Abrothallus caerulescens, Arthonia phaeophysciae, Athelia arachnoidea, Cercidospora macrospora, Clypeococcum hypocenomycis, Cornutispora lichenicola, Erythricium aurantiacum, Heterocephalacria physciacearum, Intralichen christiansenii, Lichenochora obscuroides, Lichenoconium erodens, L. lecanorae, L. usneae, Lichenodiplis lecanorae, Lichenostigma cosmopolites, Lichenothelia convexa, L. scopularia, Marchandiomyces corallinus, Monodictys epilepraria, Muellerella pygmaea, M. erratica, Pronectria leptaleae, Pyrenochaeta xanthoriae, Sclerococcum sphaerale, Sphaerellothecium propinquellum, Stigmidium fuscatae, S. squamariae, S. xanthoparmeliarum, Taeniolella phaeophysciae, T. punctata, Xanthoriicola physciae) new to the Teteriv River Basin are provided. Further five species (Cercidospora crozalsiana, Lichenostigma epipolina, Lichenothelia tenuissima, Polysporina subfuscescens and Taeniolella beschiana) are new to Ukraine. Additional localities for all newly reported species are listed.

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Authors: Margit Kollaricsné Horváth, Borbála Hoffmann, István Cernák, Szilveszter Baráth, Zsolt Polgár and János Taller

Introduction

Significant differences in nitrogen use efficiency (NUE) were detected previously among potato cultivars. Exploration of the genetic background may facilitate the breeding of cultivars with highly effective nitrogen use.

Methods

Expression of NUE genes was analyzed at three different N-supply levels in five potato genotypes. Correlations of NUE gene expressions and agronomical parameters with such indices as the nitrogen uptake efficiency, nitrogen utilization efficiency, NUE, and harvest indices were analyzed.

Results

The correlations between expression level of the nitrate–reductase, nitrite–reductase, ammonium transporter, and asparagine synthase genes and different agronomically important parameters were detected.

Discussion

Our results contribute to more rational, genotype-dependent nitrogen use in potato production and have relevance in breeding of new cultivars with better nitrogen utilization, as well as in production of seed potato.

Open access
Authors: Fahar Ibtisham, Yi Zhao, Jiang Wu, Aamir Nawab, Xiao Mei, GuangHui Li and Lilong An

Introduction

The ability for isolation and in vitro propagation of spermatogonial stem cells (SSCs) offer a base for studies on spermatogenesis, and also contribute to the development of new methods for the preservation of livestock and animal genetic modification. The aim of this study was to find the optimal isolation and culture condition for efficient propagation of SSCs.

Methods

Three different isolation methods (mechanical, one-, and two-step enzymatic digestion) were compared to find the optimal isolation method. To find the best culture conditions for in vitro propagation, isolated SSCs were cultured for 7 days in three different culture conditions supplemented with 10% FBS, 0.25% BSA, and 10% KSR, respectively.

Results

The result showed that two-step enzymatic digestion produced a significant high fraction of live cells compared the other two. Non-adhering cells collected after 48 hr and cultured in BSA- and KSR-supplemented medium had a significantly high number of SSCs clump formation compared to FBS-supplemented group. The expression of CD9 confirmed that cell clumps were SSCs clumps. Spermatogonial stem cells cultured in BSA-supplemented medium were positive for NGN3 and PLZF expressions, whereas negative for Stra8 (a meiotic-specific gene) expression, suggesting that most of the cells were undifferentiated SSCs in BSA culture system. In contrast, in FBS- and KSR-supplemented groups, the SSCs were positive for NGN3, PLZF, and Stra8.

Conclusion

These data revealed that two-step enzymatic digestion is the best method for the isolation, and 0.25% BSA-supplemented culture condition is effective for optimal in vitro propagation of SSCs.

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From the combined phylogenetic analysis of multi-locus sequence data of the Lecanoraceae including two nuclear protein-coding markers (RPB2 and RPB1), the internal transcribed spacer and a fragment of the mitochondrial small subunit, found that the originally monotypic eastern Asian genus Verseghya is positioned within the Verseghya-Lecidella-Pyrrhospora clade of the Lecanoraceae and includes one more taxon Verseghya thysanophora widely distributed in Northern Hemisphere.

The genus Lecidella forming the Lecidella-Glaucomaria subclade within the same Verseghya-Lecidella-Pyrrhospora clade of the Lecanoraceae found to have tendency to be polyphyletic after including the recently described eastern Asian taxon Lecidella mandshurica into phylogenetic analysis of the Lecanoraceae. It is shown that Lecidella mandshurica was previously recorded from China sub Lecidella aff. elaeochroma.

The originally monotypic eastern Asian genus Sedelnikovaea forming a monophyletic branch within the Sedelnikovaea-Lecanoropsis subclade and being in out-position to the Rhizoplaca-Protoparmeliopsis s. str. clade of the Lecanoraceae found to include three more taxa, i.e. Sedelnikovaea marginalis, S. pseudogyrophorica, and S. subdiscrepans.

The Eurasian Protoparmeliopsis bolcana, and the eastern Asian P. kopachevskae, are illustrated for the first time as being positioned within the Protopameliopsis branch of the Lecanoraceae, while the South Korean ‘Protoparmeliopsis’ chejuensis found to be positioned in separate monophyletic branch from all other branches of the Rhizoplaca-Protoparmeliopsis s. l. clade of the Lecanoraceae.

The genus Polyozosia A. Massal. as earlier name for the former Myriolecis branch of the Lecanoraceae is accepted as far the type species of the latter genus, i.e. P. poliophaea, found to be positioned within this branch. The Polyozosia robust monophyletic branch is positioned in the outermost position in the Rhizoplaca-Protoparmeliopsis s. str. clade of the Lecanoraceae.

Position and species content of the accepted genera Glaucomaria, Lecanoropsis, Omphalodina, Polyozosia, and Straminella are discussed in separate nrITS and mtSSU, and combined phylogeny based on concatenated sequences of nrITS, mtSSU, RPB2 and RPB1 genes.

Fourty new combinations are proposed: Glaucomaria bicincta, G. carpinea, G. leptyrodes, G. lojkaeana, G. subcarpinea, G. sulphurea, G. swartzii, G. swartzii subsp. caulescens, G. swartzii subsp. nylanderi, Lecanoropsis anopta, L. macleanii, Omphalodina chrysoleuca, O. huashanensis, O. opiniconensis, O. phaedrophthalma, O. pseudistera, Palicella anakeestiicola, Polyozosia albescens, P. andrewii, P. contractula, P. crenulata, P. dispersa, P. hagenii, P. perpruinosa, P. populicola, P. pruinosa, P. reuteri, P. sambuci, P. semipallida, P. straminea, P. thuleana, Sedelnikovaea marginalis, S. pseudogyrophorica, S. subdiscrepans, Straminella bullata, S. burgaziae, S. conizaeoides, S. densa, S. maheui, S. varia, and Verseghya thysanophora. Validation of one name as Polyozosia perpruinosa Fröberg ex S. Y. Kondr. L. Lőkös et Farkas is also proposed.

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5-Aminolevulinic acid relieves the effects of environmental stresses in plants. Therefore, the aim of our study was to evaluate the effects of 5-aminolevulinic acid (5-ALA) on the activity of the photosynthetic apparatus in spring wheat. Other analyzed parameters involved plant height, relative turgidity, membrane status, and chlorophyll level. The plant material consisted of three genotypes of spring wheat (J × Z, R × K, K × M), subjected to mild and severe drought in the early phase of vegetative development.

5-ALA showed a positive effect on the activity of the photosynthetic apparatus under water stress. The relieving action of 5-ALA on PSII was the most evident in J × Z genotype during severe soil drought. 5-ALA positively influenced the maximum photochemical efficiency of PSII (Fv/Fm), the overall performance index of PSII photochemistry (PI) and the effective quantum field of PSII (φEo). In the same genotype, the investigated acid stimulated light energy absorption (ABS/CSm), and enhanced the amount of excitation energy trapped in PSII reaction centers (TRo/CSm) and the amount of energy used for electron transport (ETo/CSm).

Moreover, 5-aminolevulinic acid showed its potential to overcome the adverse effects of water deficit on Triticum aestivum L. by increasing plant growth, relative turgidity, and chlorophyll content and reducing the degree of damage to cell membranes at the early phase of vegetative development.

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Introduction

Drought is a major environmental factor that limits crops productivity. To cope with the adverse effects of drought, plants have evolved various adaptive mechanisms, such as accumulation of osmolytes. Polyamines (PAs) play an important role in the plant growth and development and response to abiotic stresses. This experiment was conducted to investigate the role of exogenous PAs on drought tolerance of mung bean.

Methods

Mung bean seeds were soaked in 0 or 100 µM putrescine (Put), spermidine (Spd), spermine (Spm), or their mixture for 10 hr. Then, treated seeds were sown in the field and were exposed to drought stress condition.

Results

The growth attributes including shoot length, biomass, leaf area index (LAI), and grain yield markedly reduced due to drought stress. Drought stress also decreased soluble protein content, relative water content (RWC), chlorophyll value, stomatal conductance (g s), and net photosynthetic rate (P N) but increased malondialdehyde (MDA), total soluble sugars (TSS), and proline contents. Nonetheless, seed priming with the mixture of PAs alleviated adverse effects of drought stress and improved all growth attributes. Exogenous application of PAs also increased soluble protein content, RWC, chlorophyll value, P N, and more increased TSS and proline contents but decreased g s and MDA level.

Discussion

These results indicated that seed treatment with PAs especially combined treatment of Put + Spd + Spm could enhance drought tolerance of mung bean plants through the accumulation of osmoprotectants, improving water status, chlorophyll value, and P N as well as reduction of oxidative damage.

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Authors: Luis Francisco Sánchez-Anguiano, Nadia Velázquez-Hernández, Fernando Martín Guerra-Infante, Marisela Aguilar-Durán, Alma Rosa Pérez-Álamos, Sergio Estrada-Martínez, José Antonio Navarrete-Flores, Ada Agustina Sandoval-Carrillo, Elizabeth Irasema Antuna-Salcido, Jesús Hernández-Tinoco and Cosme Alvarado-Esquivel

Purpose: We aimed to determine the association between Chlamydia trachomatis infection and female sex work, and the association between sociodemographic, obstetric, and behavioral characteristics of female sex workers and C. trachomatis infection.

Methods: Through a case–control study design, we studied 201 female sex workers and 201 age-matched women without sex work in Durango City, Mexico. C. trachomatis DNA was detected in cervical swab samples using polymerase chain reaction.

Results: C. trachomatis DNA was detected in 32 (15.9%) of the 201 cases and in 6 (3.0%) of the 201 controls (odds ratio [OR] = 6.15; 95% confidence interval [CI]: 2.5–15.0; P < 0.001). The frequency of infection with C. trachomatis in female sex workers did not vary (P > 0.05) regardless of the history of pregnancies, deliveries, cesarean sections, or miscarriages. Regression analysis of the behavioral characteristics showed that infection with C. trachomatis was associated only with consumption of alcohol (OR = 2.39; 95% CI: 1.0–5.71; P = 0.04).

Conclusions: We conclude that C. trachomatis infection is associated with female sex work in Durango City, Mexico. This is the first age-matched case–control study on the prevalence of C. trachomatis infection in female sex workers in Mexico using detection of C. trachomatis DNA in cervical samples.

Open access

Four amphiploid lines (SHW) based on T. monococcum (Tm) and T. boeoticum (Tb) were crossed to T. durum varieties to generate 13 combinations. Field germination and winter survival of hybrid plants in F2 were assessed. Among all crosses, those with SHW8A-Tb and SHW9A-Tm showed highest field germination but with different degrees of spike fragility. The variation on seed number and weight per main spike was studied in F4–6 from SHW8ATb/ Progres and SHW5A-Tb/Severina crosses after individual selection for these traits. Ten lines with durum phenotype from the former and three genotypes with dicoccum plant shape from the latter cross were developed. SDS-PAGE indicated the presence of HMW-GS 1Ax2*+1Aynull subunits in four lines, among which 1Ax2* was inherited from T. boeoticum acc.110 through SHW8A-Tb. Most of the selected genotypes possessed γ-gliadin45, which was relating to good end-use quality. Powdery mildew testing showed that all progenies resulted from the SHW8A-Tb/Progres were susceptible to 12 races of the pathogen, while three lines derived from the SHW5A-Tb/Severina cross behaved differently: G32 expressed resistance to six, G33 to 2, and G34 to 5 races. The selected genotypes from crosses involving SHW with T. boeoticum exhibited good breeding performance compared to tetraploid wheat parents, and might be of breeding interest to further research.

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Winter wheat samples infected by eyespot were collected during the years 2015–2017. In total 143 Oculimacula spp. isolates were obtained and determined by PCR. Oculimacula yallundae isolates prevailed (122) over Oculimacula acuformis isolates (12) and 9 mixed isolates of both species. O. acuformis predominated only on one locality. The reaction of 104 Oculimacula spp. isolates to ten different fungicides was evaluated in laboratory tests on Petri dishes. The highest efficacy showed the combination of epoxiconazole + fluxapyroxad + pyraclostrobin and the lowest efficacy was evaluated after application of prothioconazole + trifloxystrobin. The decrease of efficacy of fungicide no. 6 (prothioconazole + trifloxystrobin) has been observed since 2015. The sensitivity of 114 Oculimacula spp. isolates to prochloraz has been tested. More than half of the isolates (58%) showed low to medium resistance. One isolate of O. yallundae from the year 2017 showed high resistance to prochloraz (ED50 ranged 1.7 μg ∙ ml–1). The rest of the isolates (42%) were sensitive to prochloraz.

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Introduction

Endophytic fungi associated with desert plants have a crucial role to enable these plants to tolerate abiotic stress, such as heat and drought.

Methods

In this study, a thermophilic fungal endophyte was isolated from a hot desert-adapted plant, Cullen plicata Delile. The endophytic fungus was (molecularly) identified as Thermomyces lanuginosus, and inoculated plants were coded as E+ and the control as E−.

Results

This fungus had an effective growth-promoting activity on its host plant and increased the plant resistance to heat stress as well.

Discussion

Our findings demonstrate that thermophilic fungal endophytes can enhance drought and heat stress tolerance in desert plants by ecophysiological mechanisms and improve growth of its host plants.

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Authors: Hans Kollenda, Hagen Frickmann, Rania Ben Helal, Dorothea Franziska Wiemer, Habiba Naija, Mohamed Sélim El Asli, Melanie Egold, Joachim Jakob Bugert, Susann Handrick, Roman Wölfel, Farouk Barguellil and Mohamed Ben Moussa

Background: Carbapenem-resistance is frequently detected in Enterobacteriaceae isolated from patients in Tunisia. The study was performed to identify frequent carbapenemases in Tunisian isolates.

Methods: Between May 2014 and January 2018, 197 ertapenem-resistant Enterobacteriaceae were isolated at the microbiological department of the Military Hospital of Tunis. The strains were phenotypically characterized and then subjected to in-house polymerase chain reaction (PCR) targeting the carbapenemase genes blaIMP, blaVIM, blaNDM, blaSPM, blaAIM, blaDIM, blaGIM, blaSIM, blaKPC, blaBIC, and blaOXA-48.

Results: The assessed 197 ertapenem-resistant Enterobacteriaceae from Tunis comprised 170 Klebsiella pneumoniae, 19 Enterobacter cloacae, 6 Escherichia coli, 1 Citrobacter sedlakii, and 1 Enterobacter asburiae. Thereby, 55 out of 197 isolates (27.9%) were from blood cultures, suggesting a systemic disease. The carbapenemase gene blaOXA-48 quantitatively dominated by far with 153 detections, followed by blaNDM with 14 detections, which were distributed about the whole study interval. In contrast, blaBIC and blaVIM were only infrequently identified in 5 and 3 cases, respectively, while the other carbapenamases were not observed.

Conclusions: The carbapenemase gene blaOXA-48 was identified in the vast majority of ertapenem-resistant Tunisian Enterobacteriaceae while all other assessed carbapenemases were much less abundant. In a quantitatively relevant minority of isolates, the applied PCR-based screening approach did not identify any carbapenemases.

Open access
Authors: I. Kärnefelt, L. Lőkös, M. R. D. Seaward, A. Thell and N. Thell
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Authors: M. Demichelis, L.S. Vanzetti, J.M. Crescente, M.M. Nisi, L. Pflüger, C.T. Bainotti, M.B. Cuniberti, L.R. Mir and M. Helguera

Seed storage proteins (gliadins and glutenins) play a key role in the determination of dough and bread-making quality in bread wheat. This is due to the interaction between high and low molecular weight glutenins subunits and gliadins, via complex inter- and intramolecular bondings. In contrast to high molecular weight glutenins, low molecular weight glutenins and gliadins analysis is difficult due to the large number of expressed subunits and coding genes. For these reasons the role of individual proteins/subunits in the determination of wheat quality is less clear. In this work we studied the effect of gene clusters Glu-A3/Gli-A1 and Glu-D3/Gli-D1 in bread-making quality parameters using 20 F4-6 families from the cross Prointa Guazú × Prointa Oasis, both cultivars carrying identical high molecular weight glutenins subunits composition and presence of 1BL/1RS wheat-rye translocation, but differing in Glu-A3/Glu-D3 low molecular weight glutenins subunits and Gli-A1/Gli-D1 gliadins patterns. ANCOVA analysis showed a significant contribution of the Glu-D3/Gli-D1 gene cluster provided by Prointa Guazú to gluten strength explained by mixograph parameters MDS and PW, and Zeleny Test. Markers tagging Prointa Guazú Glu-D3/Gli-D1 alleles are available for strong gluten selection in breeding programs.

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Hypodaphnis zenkeri is a monotypic taxon whose position is basal in the phylogenetic tree of the family Lauraceae. Cuticular information on the plant is lacking. Given the systematic relevance of this character in the family and absence of its record for the species, the leaves of the species were investigated with the aid of light and scanning electron microscopy. Also, volatile organic compounds in leaves and fruits were studied with Gas Chromatography-Mass Spectrometry (GC-MS), for the first time. Taxonomically useful cuticular features of the species include long stomatal rim and aperture, granulated periclinal walls on the adaxial surface and superficial stomatal orientation. The leaves and fruits of the plant are rich in volatile organic compounds such as 1,2-benzene-dicarboxylic acid, hexadecanoic acid ester and stigmasta-3,5-diene. Based on these features, the species can be distinguished from other related taxa in the family.

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Three lichenicolous fungi, Abrothallus peyritschii, Lichenochora verrucicola and Sclerococcum montagnei, collected from Burdur and Bitlis provinces, are reported as new to Turkey, the latter species is also new to Asia. Short descriptions, including geographical distributions, hosts and comparisons with similar taxa are provided.

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Authors: J.C. Zheng, T. Liu, J.Q. Li, X. Wang, W.Y. Li, F. Xu and Q.W. Zhan

Barley stripe mosaic virus (BSMV)-based virus induced gene silencing (VIGS) is an effective strategy for rapid determination of functional genes in wheat plants. ERECTA genes are reported to regulate stomatal pattern of plants, and manipulation of TaERECTA (a homologue of ERECTA in bread wheat) is a potential route for investigating stomatal development. Here, the leucine-rich repeat domains (LRRs) and transmembrane domains of TaERECTA were selected to gain BSMV:ER-LR and BSMV:ER-TM constructs, respectively, targeting TaERECTA for silencing in wheat cultivars ‘Bobwhite’ and ‘Cadenza’, to identify the function of TaERECTA on stomatal patterns. The results showed that reduced expression of TaERECTA caused an increased stomatal and epidermal cell density by average 13.5% and 3.3%, respectively, due to the significantly reduced size of leaf epidermal and stomatal cells, and this led to an increase in stomatal conductance. These suggest that modulation of TaERECTA offers further opportunities in stomatal engineering for the adaptation of photosynthesis in wheat.

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Authors: K. Hoenes, M. Hess, P. Vatter, B. Spellerberg and M. Hessling

Photoinactivation of bacteria with visible light has been reported in numerous studies. Radiation around 405 nm is absorbed by endogenous porphyrins and generates reactive oxygen species that destroy bacteria from within. Blue light in the spectral range of 450–470 nm also exhibits an antibacterial effect, but it is weaker than 405 nm radiation, and the photosensitizers involved have not been clarified yet, even though flavins and porphyrins are possible candidates.

There are significantly fewer photoinactivation studies on fungi. To test if visible light can inactivate fungi and to elucidate the mechanisms involved, the model organism Saccharomyces cerevisiae (DSM no. 70449) was irradiated with violet (405 nm) and blue (450 nm) light. The mean irradiation doses required for a one log reduction of colony forming units for this strain were 182 J/cm2 and 526 J/cm2 for 405 nm and 450 nm irradiation, respectively.

To investigate the cell damaging mechanisms, trypan blue staining was performed. However, even strongly irradiated cultures hardly showed any stained S. cerevisiae cells, indicating an intact cell membrane and thus arguing against the previously suspected mechanism of cell membrane damage during photoinactivation with visible light at least for the investigated strain. The results are compatible with photoinactivated Saccharomyces cerevisiae cells being in a viable but nonculturable state.

To identify potential fungal photosensitizers, the absorption and fluorescence of Saccharomyces cerevisiae cell lysates were determined. The spectral absorption and fluorescence results are in favor of protoporphyrin IX as the most important photosensitizer at 405 nm radiation. For 450 nm irradiation, riboflavin and other flavins may be the main photosensitizer candidates, since porphyrins do not play a prominent role at this wavelength. No evidence of the involvement of other photosensitizers was found in the spectral data of this strain.

Open access
Authors: Katja Fischer, Jan-Moritz Doehn, Christian Herr, Carolin Lachner, Annina Heinrich, Olivia Kershaw, Meike Voss, Max H. Jacobson, Achim D. Gruber, Matthias Clauss, Martin Witzenrath, Robert Bals, Birgitt Gutbier and Hortense Slevogt

In chronic obstructive pulmonary disease (COPD), acute exacerbations and emphysema development are characteristics for disease pathology. COPD is complicated by infectious exacerbations with acute worsening of respiratory symptoms with Moraxella catarrhalis as one of the most frequent pathogens. Although cigarette smoke (CS) is the primary risk factor, additional molecular mechanisms for emphysema development induced by bacterial infections are incompletely understood. We investigated the impact of M. catarrhalis on emphysema development in CS exposed mice and asked whether an additional infection would induce a solubilization of pro-apoptotic and pro-inflammatory endothelial monocyte-activating-protein-2 (EMAPII) to exert its activities in the pulmonary microvasculature and other parts of the lungs not exposed directly to CS.

Mice were exposed to smoke (6 or 9 months) and/or infected with M. catarrhalis. Lungs, bronchoalveolar lavage fluid (BALF), and plasma were analyzed.

CS exposure reduced ciliated area, caused rarefaction of the lungs, and induced apoptosis. EMAPII was increased independent of prior smoke exposure in BALF of infected mice. Importantly, acute M. catarrhalis infection increased release of matrixmetalloproteases-9 and -12, which are involved in emphysema development and comprise a mechanism of EMAPII release.

Our data suggest that acute M. catarrhalis infection represents an independent risk factor for emphysema development in smoke-exposed mice.

Open access
Authors: Pál Jakusch, Tímea Kocsis, Ilona Kovácsné Székely and István Gábor Hatvani

The aim of the present study is to extend the applicability of MRI measurements similar to those used in human diagnostics to the examination of water barriers in living plants, thus broadening their use in natural sciences. The cucumber, Cucumis sativus, and Phillyrea angustifolia, or false olive, were chosen as test plants. The MRI measurements were carried out on three samples of each plant in the same position vis-a-vis the MRI apparatus using a Siemens Avanto MRI scanner. Two different relaxation times were employed, T1, capable of histological mapping, and T2, used for the examination of water content. In the course of the analysis, it was found that certain histological formations and branching cause modifications to the intensity detected with relaxation time T2. Furthermore, these positions can also be found in T1 measurements. A monotonic correlation (cucumber: ρ = 0.829; false olive: ρ = –0.84) was observed between the T1 and T2 measurements. In the course of the statistical analysis of the signal intensities of the xylems it was concluded that they cannot be regarded as independent in a statistical sense; these changes rather depend on the anatomic structure of the plant, as the intensity profile is modified by nodes, leaves and branches. This serves as a demonstration of the applicability of MRI to the measurement of well know plant physiological processes. The special parametrization required for this equipment, which is usually used in human diagnostics, is also documented in the present study.

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Carabid beetles and spiders are at the top of the hierarchy of general invertebrate predators, which can help to reduce the abundance of harmful forest pests. They are also frequently used as environmental indicators. In this paper we analyzed the abundance, species richness and changes in carabid beetle and spider assemblages in three treatments of pine forest regeneration – natural, natural with soil prepared by ploughing and artificial with seedlings planted in ploughed soil. The most beneficial forest regeneration treatment variant of forest regeneration for carabid beetles and spiders was the natural regeneration of pine stands without any preceding soil preparation. Both taxa responded strongly to soil ploughing. We also noted the replacement of forest species by less sensitive open area species. In carabid assemblages, large changes in the trophic structure were observed, as predatory species were replaced by hemizoophages in the ploughed treatments.

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Authors: N. Sinha, V. Priyanka, K.T. Ramya, T. Leena, J.A. Bhat, Harikrishna, N. Jain, P.K. Singh, G.P. Singh and K.V. Prabhu

Abiotic stresses are major constraints to wheat productivity in many parts of the world. Tolerance to abiotic stresses can be achieved indirectly by selection for morpho-physiological traits. Physiological trait based breeding has been associated with improved performance under stress; and hence can combat and adapt wheat to drought and heat stress. Therefore, in the present study, phenotyping was carried out for agro-physiological traits in 52 diverse wheat germplasm lines under timely sown, rainfed and late sown environments for two years. Mean yield of the genotypes over the six environments were positively correlated with NDVI, days to maturity and negatively correlated with canopy temperature. The phenotypic data validated marker-trait associations of a number of meta-QTLs identified earlier for different physiological and agronomic traits. Six and seven meta-QTL genomic regions were found to be consistent in their expression for two years under rainfed/restricted irrigation and late sown environments, respectively. Expression analysis of the underlying candidate gene AK248593.1 in meta-QTL26 region revealed two folds higher expression in the NILs carrying the co-localized SSR markers. The linked markers of the thirteen meta-QTL regions associated with different traits can be used for effective transfer of the QTLs through marker assisted selection in wheat breeding programmes.

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Similarity indices are often used for measuring b-diversity and as the starting point of multivariate analysis. In this study, I used simulation to examine the direction and amount of bias in estimates of two similarity indices, Jaccard Coefficient (J) and incidence-based J (J^). I design a novel simulation to generate three sets of assemblages that vary in species richness, species-occurrence distributions, and b-diversity. I characterized assemblage differences with the ratio of [proportion of rare species in all shared species / proportion of rare species in all unshared species] (i.e., PR ss/PR us) and the Pearson’s correlation in the probabilities of shared species between two assemblages (i.e., share-species correlation). I found that J was subject to strong positive or negative bias, depending on PR ss/PR us. J^ was mainly subject to negative bias, which varied with share-species correlation. In both indices, bias varied substantially from one pair of assemblages to another and among datasets. The high variation in the bias across different comparisons of assemblages may compromise b-diversity estimation established at low sampling efforts based on the two indices or their variants.

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Authors: U. Sommer, E. Charalampous, M. Scotti and M. Moustaka-Gouni

Food chains in the pelagic zones of oceans and lakes are longer than in terrestrial ecosystems. The perception of the pelagic food web has become increasingly complex by progressing from a linear food chain (phytoplankton – crustacean zooplankton – planktivorous fish – predatory fish) to a food web because of an increasing appreciation of microbial trophic pathways, side-tracks by gelatinous zooplankton and a high prevalence of omnivory. The range of predator:prey size ratios by far exceeds the traditionally assumed range of 10:1 to 100:1, from almost equal length to 105:1. The size ratios between primary consumers and top predators are 3½ orders of magnitude bigger in pelagic than in terrestrial food webs. Comparisons between different pelagic ecosystems support ecosystem size as an important factor regulating the maximal trophic level, while energy limitation of the number of trophic levels is less well supported. An almost 1:1 relationship between ingestion by predators and prey mortality and a better chemical match between primary producer and herbivore biomass are further distinctive features of the pelagic food web whose role in explaining the higher number of trophic levels in pelagic systems needs further examination.

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Authors: Tihana Marček, Marija Viljevac Vuletić and Valentina Španić

In wheat, Fusarium fungus promotes the appearance of destructive disease named as Fusarium head blight (FHB) that can cause grain yield reduction and mycotoxin accumulation. The focus of this research was to verify the influence of Fusarium graminearum and F. culmorum on wheat genotypes with different susceptibility to FHB: “Super Žitarka” (susceptible), “Lucija” (moderately resistant) and “Apache” (resistant). The experiment was performed under field conditions by artificial spore inoculation of ears at the flowering stage. The effectiveness of antioxidative enzymes, hydrogen peroxide (H2O2) content and malondialdehyde (MDA) content were observed at several sampling points after Fusarium inoculation (3, 15 and 24 hours). “Lucija” responded to pathogen by increase of guaiacol peroxidase (POD) activity, high H2O2 and MDA content in the early post-inoculation times (3 and 15 hours), compared to control. “Super Žitarka” displayed inhibition of catalase (CAT) activity throughout the whole time course of the experiment. Infected plants of “Apache” showed notable decline in MDA content over time. Moreover, in “Apache” increased H2O2 accumulation was observed immediately after Fusarium exposure (3 and 15 hours), compared to 24 hours. Rapid overproduction of H2O2 under Fusarium stress marked “Apache” as FHB-resistant.

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A main limitation in community ecology for making quantitative predictions on species abundances is often an incomplete knowledge of the parameters of the population dynamics models. The simplest linear Lotka-Volterra competition equations (LLVCE) for S species require S 2 parameters to solve for equilibrium abundances. The same order of experiments are required to estimate these parameters, namely the carrying capacities (from monoculture experiments) and the competition coefficients (from biculture or pairwise experiments in addition to monoculture ones). For communities with large species richness S it is practically impossible to perform all these experiments. Therefore, with an incomplete knowledge of model parameters it seems more reasonable to attempt to predict aggregated or mean quantities, defined for the whole community of competing species, rather than making more detailed predictions, like the abundance of each species. Here we test a recently derived analytical approximation for predicting the Relative Yield Total (RYT) and the Mean Relative Yield (MRY) as functions of the mean value of the interspecific competition matrix a and the species richness S. These formulae with only a fraction of the model parameters, are able to predict accurately empirical measurements covering a wide variety of taxa such as algae, vascular plants, protozoa. We discuss the dependence of these global community quantities on the species richness and the intensity of competition and possible applications are pointed out.

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Authors: Carlos Florindo, Cinthia Alves Barroco, Inês Silvestre, Vera Damião, João Paulo Gomes, Barbara Spellerberg, Ilda Santos-Sanches and Maria José Borrego

Extracellular deoxyribonucleases (DNases) contribute to the spread of pathogenic bacteria through the evasion from host innate immunity. Our main objective was to evaluate the production of extracellular DNases by human and bovine Streptococcus agalactiae clinical strains and perform a correlation of genetic lineages and DNase activity with capsular type, genetic determinants, clinical origin (colonization and infection), and host (human or bovine). DNase activity was evaluated by qualitative and quantitative assays for a collection of 406 human (n = 285) and bovine (n = 121) strains. All (121/121) bovine were isolated from mastitis and revealed to be DNase (+), indicating a putative pathogenic role in this clinical scenario. From the human S. agalactiae strains, 86% (245/285) showed DNase activity, among which all strains belonging to capsular types, namely, Ia, Ib, III-2, and IV. All CC17 strains (n = 58) and 56/96 (58.3%) of the CC19 displayed DNase activity. DNase (−) strains belonged to the CC19 group. However, the subcharacterization of CC19 S. agalactiae strains through multiple-locus variable number tandem repeat analysis (MLVA), antibiotic resistance, mobile elements, and surface proteins did not provide any distinction among DNase producers and non-producers.

The production of DNases by all human CC17 strains, about two-fifths of human CC19, and all bovine strains, suggest an important contribution of DNases to hypervirulence.

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Bread wheat is the primary bread crop in the majority of countries in the world. The most important product that is manufactured from its grain and flour is yeast bread. In order to obtain an excellent bread, grain with high physical properties is needed for flour and dough. The Russian spring wheat cultivar Saratovskaya 29 is characterized by its exclusively high physical properties of flour and dough. The purpose of this work was to identify the chromosomes carrying the main loci for these traits in Saratovskaya 29 and to map them using recombinant substitution lines genotyped with molecular markers. A set of inter-varietal substitution lines Saratovskaya 29 (Yanetzkis Probat) was used to identify the “critical” chromosomes. The donor of individual chromosomes is a spring cultivar with average dough strength and tenacity. Substitution of 1D and 4D*7A chromosomes in the genetic background of Saratovskaya 29 resulted in a significant decrease in the physical properties of the dough. Such a deterioration in the case of 1D chromosome might be related to the variability of gluten protein composition. With the help of recombinant substitution double haploid lines obtained from a Saratovskaya 29 (Yanetzkis Probat 4D*7A) substitution line the region on the 4D chromosome was revealed in the strong-flour cultivar Saratovskaya 29, with the microsatellite locus Xgwm0165 to be associated with the unique physical properties of flour and dough. The detected locus is not related to the composition gluten proteins. These locus may be recommended to breeders for the selection of strong-flour cultivars. Additionally, a QTL associated with vitreousness of grain was mapped in the short arm of chromosome 7A.

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After stressing the need to keep separated the concept of variability and/or inequality and dissimilarity from that of diversity, it is suggested that diversity of a system should be measured primarily by the number of different classes (K) we can define in it (richness) by classification or identification processes. An index d, ranging between 0 and 1, that summarizes the similarity pattern within the system, can be used if necessary to transform K to a “fuzzy” diversity number, according to the idea that the higher is the similarity within the system the lower should be its diversity. Another index, r, is proposed to measure the “loss” of diversity due to similarity within the system, an index that fits the concept of “redundancy”. Since every diversity vector may be interpreted as a crisp symmetric similarity matrix, of which the Gini-Simpson’s index is the average dissimilarity, while the index of Shannon is the entropy of its eigenvalues, the index d can be chosen to quantify one among the following similarities: a) the overall average similarity of the classes considering the within classes similarity equal to 1 and the between classes similarity equal to 0 (crisp similarity pattern): this is coincident with the evenness of the proportion of importance of the classes, b) the average similarity between the classes without considering evenness, or c) the combination of the two similarities (similarity between the classes and evenness). In these last two cases, the similarity between the classes is characterizing the similarity pattern of a system in a fuzzy way (fuzzy diversity). It is stressed that the diversity of vegetation systems may be of two complementary types: plant individual-based diversity and plant community-based diversity. If we assume that each plant community type corresponds to one habitat then habitat diversity (or niche width) can be calculated for each class of plant individuals according to the number of classes of plant communities in which we can find it. Habitat diversity can be used to measure the indicator value of species or other classes of plant individuals and of plant communities. In this last case, we have to consider the distribution of plant communities in classes defined by environmental factors. It is suggested that the terminology alpha, beta, gamma diversity can be useful only if used to distinguish types of diversity in vegetation systems: alpha diversity = plant individual based diversity, gamma diversity = the union of alpha diversities, beta diversity = plant community based diversity. Thanks to the availability of mathematical tools, it is concluded that rather than being worried about measuring diversity it would be more fruitful to worry about why we are willing to measure it.

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Over the last 30 years there has been a great deal of interest in investigating patterns of species co-occurrence across space and time, which may be shaped by interspecific competition for shared resources. A good model of co-occurrence mechanisms is developed among predatory animals along a pollution gradient, where shared resources become more limited in more contaminated areas and the energy budget for detoxification is much higher. Community disassembly by heavy metal pollution may occur when the presence of toxic elements shifts patterns of species co-occurrence from structured to random. On the other hand, limited resources on a pollution gradient should lead to higher competition between dominant species. Disassembly may entail the loss of existing co-evolved interactions among species, which has ramifications for community dynamics and the quality of the functioning of polluted ecosystems. We expect an assemblage dominated by competitive species interactions to exhibit a significant segregation of taxa, whereas one dominated by mutualistic or syntrophic interactions would exhibit an aggregation of taxa. Responses of Carabidae co-occurrence patterns and changes in body size measures to heavy metal concentrations were investigated in a zinc contamination gradient in a Scots pine forest in the vicinity of Olkusz (southern Poland), at 12 study sites. The zinc concentration in the humus layer varied between 108 mg kg-1 dw to 6150 mg kg-1 dw. We used the C-score index, between all possible species pairs in a matrix. The ground beetle assemblages from the reference sites showed a significant segregation pattern. Community disassembly occurred only among assemblages in heavily polluted sites. The average value of skewness and kurtosis were significantly higher in the highly contaminated sites, indicating the greater proportion of small-bodied species in contaminated areas. The Gini coefficient was highest in the low contaminated sites, indicating the body-size inequality of carabid assemblages was greatest in the uncontaminated areas. Our data suggest that increased pollution contributes to the extinction of sensitive forest specialists with large body size and higher competitive abilities, leading to replacement by less sensitive generalists, with smaller body size and that the co-occurrence of species on heavily polluted sites is a result of unstable interactions between species in communities.

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The evolution of anthracnose symptoms on the aerial part (leaves, stems and strawberries) of three varieties Fortuna, Camarosa and Festival of strawberry plants inoculated with the conidial suspensions of Colletotrichum acutatum and Colletotrichum gloeosporioides isolates was followed. The severity index and infection coefficients increased in function of time. Seven days after inoculation they were low not exceeding 13.43% and 43.33, but they increased four weeks after inoculation, respectively, to 37.96% and 99 on strawberry plants of the Camarosa variety, 54.44% and 105 on those of Fortuna and 51.12% and 85 on those of Festival. At the sixth week, the severity index and infection coefficients became very high, reaching respectively 100% and 408 on Fortuna plants inoculated with C. gloeosporioides isolate (Coll3) followed by Coll2 (89.28% – 300), Coll1 (86.66% – 378) and Coll4 (80.45% – 198) of C. acutatum species. Similarly, the isolate Coll3 caused fruit rot; the percentage of rotten strawberries was 100% on Fortuna variety, 83.33% on Festival and 70.25% on Camarosa. A positive re-isolation of the tested Colletotrichum isolates has been noted from leaves of strawberry varieties and negative from crowns or the roots. A significant to moderate reduction in fresh and dry weights of the aerial part and roots was noted in inoculated strawberry plants compared to the control.

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Artificial gap openings cause significant changes in vegetation structure (in every forest level), thereby greatly influencing arthropod communities. Our study compared the data of two common forest floor arthropod groups, ground beetles (Coleoptera: Carabidae) and ground-dwelling spiders (Araneae) from two artificial gaps situated in a turkey oak forest. Our surveys were carried out in the Gyöngyös-plain, in Hungary. Sampling of the arthropod communities was done with pitfall traps arranged in two 70 m long transects, along the longitudinal axis of the gaps, with 15 traps in each transect, 5 m from each other. We measured the quantity and quality of the deadwood lying around within a radius of 2.5 m of each trap. We observed that the species and numbers of spider specimens were higher in the inner parts of the transects (in the gaps), while the numbers of ground beetle specimens declined in the same traps. Furthermore, the Shannon and Simpson diversity values of the ground beetles were generally lower than those of the spiders. The ordinations showed a distinct influence of the gaps on the communities. The numbers of specimens of exclusively edge-associated species were also higher in the gaps. The correlation analysis indicated significant positive correlations between the number of ground beetles and spiders and the quantity of deadwood. In addition, there were significant negative correlations between the numbers of species of both groups and the rate of decay of deadwood.

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The forest, which is exposed to fewer anthropogenic impacts, has a rich and complex community. In Hungary, the quantity of dead wood has an ever-increasing significance in the forests. The decomposition of wood starts with the xylophagous insects, followed by the appearance tinder fungus, which transforms the wood into a form suitable for decomposers. Fungus beetles decompose most of the fungus. Therefore, besides consumer organizations, demolition organizations also play an essential role in building the forest ecosystem. In Central Europe, we have a little information about the beetle communities of tinder fungi. During our research, we investigated the beetle communities of Fomes fomentarius and Trametes gibbosa, which were collected from the Sopron-mountains in West Hungary. In F. fomentarius, the most common beetle species that we found was Bolitophagus reticulatus with about 100 individuals in four fruiting bodies, while in T. gibbosa, Cis boleti had the largest number of individuals with more than 5300 in four specimens. The beetle communities in the two tinder fungi were different, the difference probably caused by the structure and the nutritional value of the fungi.

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Authors: Tamara Babic, Jelena Dinic, Sonja Stojkovic Buric, Stefan Hadzic, Milica Pesic, Dragica Radojkovic and Aleksandra Divac Rankov

Cancer drug resistance and poor selectivity towards cancer cells demand the constant search for new therapeutics. PI3K-Akt-mTOR and RAS-MAPK-ERK signaling pathways are key mechanisms involved in cell survival, proliferation, differentiation, and metabolism and their deregulation in cancer can promote development of therapy resistance. We investigated the effects of targeted inhibitors (wortmannin, GSK690693, AZD2014 and tipifarnib) towards these two pathways on early zebrafish and sea urchin development to assess their toxicity in normal, fast proliferating cells. PI3K inhibitor wortmannin and RAS inhibitor tipifarnib displayed highest toxicity while GSK690693, a pan-Akt kinase inhibitor, exhibited a less significant impact on embryo survival and development. Moreover, inhibition of the upstream part of the PI3K-Akt-mTOR pathway (wortmannin/GSK690693 co-treatment) produced a synergistic effect and impacted zebrafish embryo survival and development at much lower concentrations. Dual mTORC1/mTORC2 inhibitor AZD2014 showed no considerable effects on embryonic cells of zebrafish in concentrations substantially toxic in cancer cells. AZD2014 also caused the least prominent effects on sea urchin embryo development compared to other inhibitors. Significant toxicity of AZD2014 in human cancer cells, its capacity to sensitize resistant cancers, lower antiproliferative activity against human normal cell lines and fast proliferating embryonic cells could make this agent a promising candidate for anticancer therapy.

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Authors: Donata Grimm, Linn Woelber, Katharina Prieske, Barbara Schmalfeldt, Sascha Kürti, Chia-Jung Busch, Ingo Teudt, Oliver Brummer, Volkmar Mueller and Thomas Meyer

A subgroup of oropharyngeal squamous cell carcinomas (OSCCs) are causally linked to infection with high-risk human papillomaviruses (HR-HPVs). To evaluate the prevalence of simultaneous oral HPV infection in females with cervical high-grade squamous intraepithelial lesions (HSIL), tonsillar- and cervical smears were collected simultaneously from 73 patients and analyzed for HPV using two commercial assays, PapilloCheck (Greiner-Bio-One) and Linear Array (Roche). Only 3/73 (4.1%) tonsillar smears were HPV positive (HPV+), with HPV types 16, 35, and 45, respectively, detected by both assays (100% agreement). Concordant results were also found in 60/66 (91%) evaluable cervical smears. Of specimens, positive by both assays, typing results completely coincide in 71% (all types are identical) and partially coincide in 27% (at least one type is identical). Taken together, results of HPV detection and typing by PapilloCheck and Linear Array are highly congruent and confirm the low prevalence of HR-HPV in tonsillar smears of patients with HSIL of the uterine cervix. Our data indicate low prevalence of oropharyngeal HPV infection in patients with high-grade cervical dysplasia. The low detection rate was confirmed by using two different commercial assays with largely consistent results of HPV detection and typing, but with some variation for particular HPV types. Comparative testing of larger numbers is required to identify the HPV types prone to escape detection with particular assays.

Open access

Population dynamics models suggest that the over-all level of resource productivity plays an important role in community dynamics. One such factor of resource productivity is the quality of the host plant, which can determine the effectiveness of entomophagous (predatory and parasitoid) species by altering the growth rate of the phytophagous population via effects on fecundity, survival, and rate of development. These effects have been studied in relation to the distribution of host plants and their physiological state. However, few studies have considered the differences among plant cultivars. The objective of this study was to identify a continuous-time dynamic model, to describe the effects of different tomato cultivars on a one predatortwo prey model. The experiment was carried out under greenhouse conditions using ten tomato cultivars, with the predatory species Nesidiocoris tenuis (Reuter) (Insecta, Hemiptera, Miridae) and two prey species: the phytophagous species Bemisia tabaci (Gennadius) (Insecta, Hemiptera, Aleyrodidae) and the parasitoid species Trichogramma achaeae (Nagaraja & Nagarkatti) (Insecta, Hymenoptera, Trichogrammatidae); the latter was used as the intraguild-prey. Using the software SIMFIT, we found that a three-dimensional Lotka-Volterra type system could be well fitted to the data, estimating the phytophagous species´ growth rate, the parasitoid and predator mortality rates, the predation and parasitism rates, and the parasitoid emergence rate according to the cultivar type. The results showed an important effect of the host plant quality, by cultivar, on intraguild predation, resulting in important changes in the dynamics of phytophagous populations. These results are also discussed in relation to their importance in the biological control of pest species in greenhouse crops.

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Authors: Fedia Rebah, Chayma Ouhibi, K. H. Alamer, Najoua Msilini, Mouhiba Ben Nasri, Rebecca Stevens and Houneida Attia

We aimed to examine the response of three tomato introgression lines (IL925.3, IL925.5 and IL925.6) to NaCl stress. These lines originated from a cross between M82 (Solanum lycopersicum) and the wild salttolerant tomato Solanum pennellii, each line containing a different fragment of the S.pennellii genome. Salt-sensitive phenotypes related to plant growth and physiology, and the response of antioxidants, pigments and antioxidant enzymes were measured. In general, salt stress decreased the fresh weight of leaves, leaf area and leaf number and an increase of Na+ accumulation in aerial parts was observed, which caused a reduction in the absorption of K+ and Ca2+. Salt stress also induced a decrease in chlorophyll, carotenoids and lipid peroxidation (MDA) and an increase in anthocyanins and reduced ascorbate, although some differences were seen between the lines, for example for carotenoid levels. Guaiacol peroxidase, catalase and glutathione reductase activity enhanced in aerial parts of the lines, but again some differences were seen between the three lines. It is concluded that IL925.5 might be the most sensitive line to salt stress as its dry weight loss was the greatest in response to salt and this line showed the highest Na+ ion accumulation in leaves.

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The chemical composition of essential oil extracted from leaves of the medicinal plant Mentha longifolia (L.) Huds growing in Egypt, were determined through Gas Chromatography/Mass Spectrometry ( GC/MS). The analyses revealed that the major component of M. longifolia was Monterpene ketone (piperitone oxide). Mentha longifolia was potent for the pest Tetranychus urticae Koch with a significant increase in repellency. In addition, it exhibited strong oviposition deterrence to the pest based on a 99.4% reduction of the total number of eggs on leaf discs treated with the oil. The LC50 values of M. longifolia against eggs, nymphs and females of T. urticae by fumigant application, were 2.95, 3.47, 3.74 μL / L, while the LC90 values were 8.99, 9.41, 11.01 μL/ L, respectively.

The toxicity of M. longifolia oil by fumigant application to females and eggs of 3 predatory phytoseiid mites was tested. Neoseiulus californicus (McGregor) is extremely insusceptible to M. longifolia oil than the pest T. urticae and both phytoseiid mites, Neoseiuls barkeri (Hughes) and Typhlodromips swirskii (Athias Henriot) under laboratory conditions. When both stages of tested predatory mites, exposed to fumigant of LC50 and LC90 μL/L values reported on T. urticae, female’s mortality of N. californicus was lesser than that reported on N. barkeri and T. swirskii.

These show that the fumigant toxicity of M. longifolia oil has the highest lethal activity to the pest T. urticae and the least to the predatory mite N. californicus. Results indicated that the mode of delivery of the essential oil was largely a result of action in the vapor phase via respiratory system. Data was suggested that M. longifolia oil have the potential agent to be used in the maintainable management of T. urticae combined with N. californicus.

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The concentration (in mg kg–1 fresh weight) of two main hydroxamates, 2,4-dihydroxy- 7-methoxy-1,4-benzoxazin-3-one (DIMBOA) and 2,4-dihydroxy-1,4-benzoxazin-3-one (DIBOA), and their temporal changes were simultaneously investigated using HPLC analysis in the leaves and roots of five Pioneer® maize (Zea mays L.) hybrids to select hybrids with higher hydroxamate contents. Although significant differences were found among hybrids in leaves, youngest leaves and roots, none of them showed unambiguously higher hydroxamate contents. However, the age of the organs and the plants significantly affected hydroxamate content. DIMBOA content of leaves decreased with increasing organ and plant age. DIBOA content varied among the hybrids, but generally decreased in the initial phase and then increased. In the roots, DIMBOA content decreased during the 21-day study and although DIBOA content did not show a clear temporal tendency, differences among hybrids were detected. According to current results, hydroxamate content temporally decreases in hybridspecific patterns, which should be considered when establishing a proper sampling time frame.

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Authors: Andreas Enz, Annett Klinder, Hannah Mittelmeier, Günther Kundt, Wolfram Mittelmeier and Sarah Zaatreh

Introduction: To prevent surgical site infections (SSIs) during operation, the use of sterile surgical latex gloves is common. The aim of this study was to examine the damage of the gloves in surgeries with different mechanical stress and the influence on the kind of damages. Gloves were collected during primary arthroplasty, revision arthroplasty (hip and knee), and arthroscopy (shoulder, hip, and knee).

Materials and methods: Surgical latex operation gloves were collected from surgeons after the operation and were tested with watertightness test (ISO EN 455-1:2000).

Results: A total of 1460 surgical gloves were retrieved from 305 elective operations. On average, 15.9% of the gloves showed postoperative lesions, with the highest incidence occurring in revision arthroplasty with 25%. In primary and revision arthroplasty, the index finger of the dominant hand was most frequently affected (62.7% and 58.6%); in contrast, gloves from arthroscopies had most lesions on thumb and middle finger (42.9% each). Tear and perforation size differed from ≤1 mm to >5 mm, and primary and revision arthroplasty showed bigger damages.

Conclusions: Surgical gloves have a high malfunction, which increases with growing mechanical stress. A high rate of perforation occurred mostly in revision arthroplasty. Breaching the integrity of the gloves, especially by high mechanical loads, could lead to an increased rate of infection.

Open access

A great challenge in ecology is to link patterns in nature with the factors that determine species coexistence and community structure. In general, these patterns have been associated with different environmental conditions and species traits. The coexistence of ant species could be affected by the availability of food and nesting resources, which depend on vegetation diversity and structural complexity. In this study, we attempt to reproduce, through null models, the properties of ant community structure in areas with different physiognomy of vegetation associated to different wildfire regimes. The null model construction considered ant traits such as occurrence frequency, body size, and nest type; and site characteristics such as vegetation height and extra-floral nectar availability, and their combinations. The null models were compared to observed species segregation and nestedness patterns. Ant species were more aggregated in space than expected by chance. Vegetation height and extra-floral nectar availability were included in the most successful models in predicting ant segregation and aggregation pattern. Furthermore, ants’ body size was enough to reproduce the nestedness of species distribution in sites. Our results suggest that under post-fire conditions, habitat complexity, resource availability and species traits such as body size may be the determinants of ant community structure.

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Authors: S. Ongaro, S. Martellos, G. Bacaro, A. De Agostini, A. Cogoni and P. Cortis

The Mediterranean is one of the major biodiversity hotspots of the world. It has been identified as the “core” of the speciation process for many groups of organisms. It hosts an impressive number of species, many of which are classified as endangered taxa. Climate change in such a diverse context could heavily influence community composition, reducing ecosystems resistance and resilience. This study aims at depicting the distribution of nine orchid species in the island of Sardinia (Italy), and at forecasting their future distribution in consequence of climate change. The models were produced by following an “ensemble” approach. We analysed present and future (2070) niche for the nine species, using Land Use and Soil Type, as well as 8 bioclimatic variables as predictors, selected because of their influence on the fitness of these orchids. Climate change in the next years, at Mediterranean latitudes, is predicted to results mainly in an increase of temperature and a decrease of precipitation. In 2070, the general trend for almost all modelled taxa is the widening of the suitable areas. However, not always the newly gained areas have high probability of presence. A correct interpretation of environmental changes is needed for developing effective conservation strategies.

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