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Zoopsidella grahamii sp. nov., related to the Australasian Z. caledonica, is described from the Andes of Central Peru (Oxapampa Province) and southern Ecuador. It is distinguished from Z. caledonica by the smaller plant size, much lower number of lobe cells and different leaf shape, and by the much more elongate perianth mouth lobes consisting of a row of 6-7 narrowly rectangular cells. Riccardia gradsteinii sp. nov., from the same general area in Peru as Z. grahamii, is unique among all dendroid species of the genus by the broad, frilled wings of the main axis, being split into complicatedly bent and strongly crispate scales.

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After the examination of the Cryptogam collection in the Herbarium of the University of Science, Vietnam National University Ho Chi Minh City (PHH), 25 species proved to be new to Vietnam, including one hornwort and 24 liverworts. Among them, four genera: Denotarisia Grolle, Gongylanthus Nees, Leiomitra Lindb. and Lepicolea Dumort. are new records for the country. Diagnostic characters and illustrations are given for some taxa, as well as locality notes and habitat descriptions are provided for each collecting area.

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Fungal diseases pose a great challenge to Canadian barley production, among which are Fusarium head blight (FHB), yellow rust and scald. An integrated management approach is needed to mitigate these diseases, in which breeding for host resistance is the most effective component. Constant evaluation of advanced breeding lines for their resistance to the diseases is important for making steady progression. The main objective of this study was to screen 1,174 barley accessions, from a collaborative project between the Field Crop Development Center (FCDC), Alberta, Canada, and the International Maize and Wheat Improvement Center (CIMMYT), Mexico for their reactions to the three diseases. For FHB a 1-5 scale was employed to discard the very susceptible material in 2012 and 2013. In 2014, 514 most resistant lines having the score 1 in 2013 were re-evaluated in a replicated experiment. The most promising 166 genotypes were selected and advanced for their last evaluation in 2015 where FHB index was measured. Simultaneously, these 166 genotypes were subjected to two more experiments to test their reactions against stripe rust and scald. Eighteen two-rowed barley genotypes exhibiting broad-spectrum resistance to all of the three evaluated diseases were identified in addition to 40 lines combining FHB resistance with resistance to Mexican isolates and natural fungal population of either of the two foliar diseases and could be utilized in breeding programs aimed at improving resistance to multiple barley leaf and head blight diseases.

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A cogent medicinal and aromatic plant, Ziziphora clinopodioides (Lamiaceae) is a perennial herb, its aerial parts is used as a wild vegetable or additive in foods to proffer pleasant aroma and flavour. There are many discussions about the intraspecific classification of this species and several subspecies have been introduced for it in different flora. These subspecies are morphologically very similar and identification of them is very difficult and in some cases, impossible. Therefore, in the present study, the pollen grains morphology of nine subspecies (32 specimens) of Z. clinopodioides were probed and documented in details utilising the scanning electron microscopy (SEM). In total, eleven pollen morphological characteristics were investigated and analysed by PAST software. The obtained results showed that pollen grains were hexacolpate and their equatorial views were sub-oblate to prolate. The exine ornamentation types of the pollen grains are bireticulate, microreticulate, reticulate and bireticulate-reticulate. The ANOVA test did not show significant difference for the studied quantitative traits. Although, the results of the multivariate analysis revealed a high diversity amongst the specimens even in the specimens of a single subspecies; it did not confirm the separation of subspecies in Z. clinopodioides.

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The increasing economic importance of triticale (×Triticosecale Wittm.) makes this synthetic hybrid cereal an interesting object of genetic studies. Genomic regions (QTL) of morphological winter triticale traits were determined using the mapping population of 89 doubled haploids lines (DHs) developed from F1 hybrid of cv. ‘Hewo’ and cv. ‘Magnat’ accompanied with the genetic map consisting of 20 linkage groups assigned to the A (7), B (7), and R (6) genomes (total of 3539 DArT, SNP-DArT and SSR markers, length of 4997.4 cM). Five independent experiments were performed in the field and greenhouse controlled conditions. A total of 12 major QTLs located on 2B, 5A, 5R, and 6B chromosomes connected to the stem length, the plant height, the spike length, the number of the productive spikelets per spike, the number of grains per spike, and the thousand kernel weight were identified by a composite interval mapping (CIM).

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Barley recombinant lines obtained from crosses and backcrosses of common barley (Hordeum vulgare L.) cultivars Emir and Golden Promise with bulbosus barley grass (H. bulbosum L.) were tested against differential set of 14 Blumeria graminis D.C. Golovin ex Speer f. sp. hordei – synamorph Erysiphe graminis DC. f. sp. hordei Em Marchall isolates, pathogenic fungus causing powdery mildew. Powdery mildew resistance was found in 22 from 24 lines tested. Presence of unknown genes was postulated in 13 lines. In six of these lines the unknown genes were postulated present besides Mla12 allele originated from H. vulgare parent (cv. Emir). The only line resistant to infection, from all isolates used, was 181P94/1/3/1/1/1-2. Four other lines could be considered highly resistant, because they were susceptible to only one powdery mildew isolate. The possibilities to use the hybrid lines with identified resistance to powdery mildew, especially line 181P94/1/3/1/1/1-2 in barley breeding programs were discussed.

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Triticale is derived from a cross between wheat and rye and the leaf rust pathogen of wheat, Puccinia triticina (Pt), and that of rye, P. recondita sensu stricto (Pr), can potentially cause disease in this crop. Recent studies showed that wheat rust fungi could adapt to warmer temperatures. In this paper, we report on the comparative virulence of three Pt races and one Pr isolate (all were collected in South Africa) on triticale as well as their in vitro response to temperature. Seedling infection types (SITs) of 169 triticale entries to Pt races 3SA144 (North American code SDDN), 3SA145 (CCPS) and 3SA248 (CFPS) and Pr isolate UVPr2 revealed that 3SA144 is the most virulent with 106 triticale entries found susceptible to this race. The three Pt races were avirulent to the four rye cultivars included as controls. UVPr2 was avirulent on all the triticale entries and 49 entries were considered resistant to the Pt races tested. Freshly harvested urediniospores of the above isolates were tested at constant temperature regimes of 10 °C, 22.5 °C and 35 °C to study germination characteristics. Mean urediniospore germination percentages as determined for 3SA144 (61.3%) and UVPr2 (62.6%) were significantly lower when compared to 3SA145 (83.7%) and 3SA248 (84.9%). Race 3SA144 was most sensitive to the higher temperature regime of 35 °C (5.2% germination). Among the investigated races, 3SA144 showed significantly lower mean germ tube elongation rates at all three incubation temperatures. This is the first report of differences in temperature adaptation between Pt races from SA.

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The separate roles of ethylene and gibberellins on seed germination have not been clearly established. This has limited full utilisation of these hormones in barley malting. This study was carried out to investigate the roles of gibberellins and ethylene on the germination physiology of ‘Puma’ barley seeds. Germination curves, percent germination, rootlets length and respiration rates of seeds treated with ethylene, 1-methylcyclopropane (1-MCP), gibberellic acid (GA3), daminozide (B-nine), GA3 + ethylene, GA3 + 1-MCP, ethylene + B-nine, 1-MCP + B-nine and the control were compared after 24, 48 and 72 h from soaking, respectively. GA3 and ethylene treatments were used to investigate the effects of increasing endogenous ethylene and GA3 levels, respectively. B-nine and 1-MCP treatments were used to assess the effects of inhibiting gibberellins synthesis and ethylene perception, respectively. Combination treatments were used to assess hormonal interactions. GA3 and ethylene treatments suppressed germination after 24 h, but, had no effect after 48 and 72 h, respectively. B-nine, ethylene + B-nine and 1-MCP + B-nine suppressed germination, rootlet elongation and respiration after 24, 48 and 72 h, respectively. 1-MCP and GA3 + 1-MCP stimulated germination after 24 h, but, had no effect after 48 and 72 h, respectively. GA3 + ethylene treatment suppressed germination and rootlet elongation but stimulated respiration after 24 h. Ethylene suppressed rootlets elongation after 24, 48 and 72 h from soaking, respectively. GA appeared to be the dominant germination hormone, and ethylene, to regulate the rate of germination through suppression of rootlets elongation.

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Stability and adaptability of 25 bread wheat (Triticum aestivum L.) cultivars were evaluated for genotype × environment interaction (G × E) and yield stability across two environments over 2 years (2014 and 2015).

Materials and methods

Five improved varieties (Haidra, Salammbô, Tahent, Utique, and Vagua) released in Tunisia and 20 introduced genotypes (V1–V20) have been tested under two contrasted environments during 2 years characterized by different precipitations in the northwest of Tunisia. Several statistical approaches were conducted to evaluate yield stability: (a) regression coefficient (bi), (b) deviation from regression (Sdi), (c) ecovalence (Wi), (d) Hühn stability (Sli), and (e) AMMI stability value.


A standard multifactor analysis of variance test showed that the main effects due to genotypes, locations, and the interaction (genotype × locations) were highly significant. The highly significant interactions indicate that genotypes need to be tested during several years and at different locations for selecting the most stable one. The results showed that all statistical analyses allowed classifying the 25 studied genotypes according to their grain yield level (low, medium, or high), their adaptability to different environments.


Tahent variety was confirmed to be most valuable due to its high production level, stability and its adaptability to variable environments including unfavorable ones.

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European Journal of Microbiology and Immunology
Authors: Isabel Stephany-Brassesco, Stefan Bereswill, Markus M. Heimesaat, and Matthias F. Melzig

Antibiotic resistance of Streptococcus pneumoniae has risen to worrying levels in the past few decades worldwide, and subsequently, effective treatment of respiratory tract infections has become even more challenging. While the need to develop new strategies to combat bacterial infections is urgent, novel antibiotic compounds are no longer a priority of the pharmaceutical industry. However, resistance-modifying agents can alleviate the spread of antibiotic resistance and render existing antibiotics effective again. In the present study, we aimed to determine the combinatory antimicrobial effects of the commercial herbal product Cefabronchin® and antibiotic compounds, such as amoxicillin and clarithromycin, on 6 clinical isolates of S. pneumoniae. Therefore, the minimal inhibitory concentration (MIC) of each agent before and after adding Cefabronchin® at different concentrations was determined by applying the checkerboard method. Sub-inhibitory concentrations of the added Cefabronchin® were found to reduce the MIC down to between 3.4% and 29.2% of the amoxicillin MIC and down to between 10.4% and 45.8% of the clarithromycin MIC in all 6 strains. In conclusion, this study provides evidence for the improved antimicrobial effects of commonly used antibiotics in combination with Cefabronchin® in order to combat infections with antibiotic-resistant S. pneumoniae strains.

Open access