Authors:Jana Niemz, Stefanie Kliche, Marina C. Pils, Eliot Morrison, Annika Manns, Christian Freund, Jill R. Crittenden, Ann M. Graybiel, Melanie Galla, Lothar Jänsch and Jochen Huehn
Using quantitative phosphopeptide sequencing of unstimulated versus stimulated primary murine Foxp3+ regulatory and Foxp3− conventional T cells (Tregs and Tconv, respectively), we detected a novel and differentially regulated tyrosine phosphorylation site within the C1 domain of the guanine-nucleotide exchange factor CalDAG GEFI. We hypothesized that the Treg-specific and activation-dependent reduced phosphorylation at Y523 allows binding of CalDAG GEFI to diacylglycerol, thereby impacting the formation of a Treg-specific immunological synapse. However, diacylglycerol binding assays of phosphomutant C1 domains of CalDAG GEFI could not confirm this hypothesis. Moreover, CalDAG GEFI−/− mice displayed normal Treg numbers in thymus and secondary lymphoid organs, and CalDAG GEFI−/− Tregs showed unaltered in vitro suppressive capacity when compared to CalDAG GEFI+/+ Tregs. Interestingly, when tested in vivo, CalDAG GEFI−/− Tregs displayed a slightly reduced suppressive ability in the transfer colitis model when compared to CalDAG GEFI+/+ Tregs. Additionally, CRISPR-Cas9-generated CalDAG GEFI−/− Jurkat T cell clones showed reduced adhesion to ICAM-1 and fibronectin when compared to CalDAG GEFI-competent Jurkat T cells. Therefore, we speculate that deficiency in CalDAG GEFI impairs adherence of Tregs to antigen-presenting cells, thereby impeding formation of a fully functional immunological synapse, which finally results in a reduced suppressive potential.
Authors:A. M. Semenov, M. S. Sokolov, A. P. Glinushkin and V. I. Glazko
In the review traditional characteristics of the soil quality are discussed. Soil health (SH) along with its soil quality and fertility, is considered as the most important, functional characteristic of any soil ecosystem (SE). The consistent patterns and results of the study of structure and functions of the microbial community (MC) of the soil ecosystem were generalized to substantiate the quantitative parameters of soil health. The author’s developments for definitions of soil and soil health are given. The prospects of using the parameters of SH for diagnostics at recovery and biological rehabilitation of technogenically disturbed soils are proposed.
Authors:István Takács, Ákos Takács, Anikó Pósa and Gyöngyi Gyémánt
Control of hyperglycemia is an important treatment in metabolic disorders such as type II diabetes and obesity. α-Amylase, as the first enzyme of glucose release from dietary polysaccharides, is a potential target to identify new sources of novel anti-obesity and anti-diabetic drugs. In this work, different herbal extracts as α-amylase inhibitors were studied by measuring the rate of the cleavage of a maltooligomer substrate 2-chloro-4-nitrophenyl-β-D-maltoheptoside. Measurement of chromophore containing products after reversed phase HPLC separation was used for α-amylase activity measurement. Rates of hydrolysis catalysed by human salivary α-amylase were determined in the presence and absence of lyophilised water extracts of eleven herbs. Remarkable bioactivities were found for extracts of Cinnamomum zeylanicum Blume (bark), Camellia sinensis L. (leaf), Ribes nigrum L. (leaf), Laurus nobilis L. (leaf), Vaccinium macrocarpon Aiton (fruit) and Syzygium aromaticum L. (bud). Determined IC50 values were in 0.017–41 μg/ml range for these six selected plant extracts. Our results confirm the applicability of this HPLC-based method for the quick and reliable comparison of plants as α-amylase inhibitors.
Authors:J. Milander, Ž. Jukić, S. Mason, T. Galusha and Z. Kmail
Maize (Zea mays L.) yield component analysis is limited. Research was conducted in 2012 and 2013 at Zagreb, Croatia and Mead, Nebraska, United States with the objective to determine the influence of environment, hybrid maturity, and plant population (PP) on maize yield and yield components. Three maturity classes of maize hybrids were produced at five PP ranging from 65,000 to 105,000 plants ha−1 under rainfed conditions. Yield, ears m−2, rows ear−1, ear circumference, kernels ear−1, kernels row−1, ear length, and kernel weight were determined. Average yield was 10.7 t ha−1, but was variable for hybrids across PP. The early maturity-hybrids had lesser ear circumference, more kernels ear−1, greater ear length, and fewer rows ear−1 than mid- and late-maturity hybrids. Kernels ear−1 had the highest correlation with yield (r = 0.47; P < 0.01 for early-maturity hybrids; r = 0.55; P < 0.01 for the mid- and late-maturity hybrids). Path analysis indicated that ears m−2, kernels ear−1 and kernel weight had similar direct effects on yield for early-maturity hybrids (R = 0.41 to 0.48) while kernels ear−1 had the largest direct effect (R = 0.58 versus 0.32 to 0.36) for the midand late-maturity hybrids. Rows ear−1 had an indirect effects on yield (R = 0.30 to 0.33) for all hybrids, while kernels row−1 had indirect effect (R = 0.46) on yield for mid- and latematurity hybrids. Yield component compensation was different for early-maturity hybrid than the mid- and late-maturity hybrids, likely due to the proportion of southern dent and northern flint germplasm present in these hybrids.
Authors:Rattanpreet Kaur and Vikramjit Kaur Zhawar
Wheat cultivar PBW644 (drought tolerant) and PBW343 (drought sensitive) were found as ABA-higher sensitive and ABA-lesser sensitive, respectively, in the screen of six wheat cultivars. Both cultivars were studied for H2O2 (ROS)/nitric oxide (NO)-regulation of growth and phenolic metabolism under ABA and water stress (WS) by supplying ROS/NO producers as well as scavengers. Endogenous ROS/NO under ABA/WS increased growth, such effect was higher in PBW644. In PBW343, reduced growth under WS was improved by exogenous ROS/NO. Exogenous ROS/NO under ABA/WS decreased lignin and increased phenolics in PBW343 but such relation was not found in PBW644. Endogenous NO under WS increased flavonoids in both cultivars. Both ROS/NO under ABA/WS increased flavonoids in PBW644, however, in PBW343, only ROS increased these in roots. Under WS, PBW644 showed higher levels of cell wall peroxidase (CW-POX) and lower levels of soluble peroxidase (S-POX) than PBW343. However, under ABA, it showed higher levels of both peroxidases. ROS/NO signals under ABA increased both types of POX in both cultivars while under WS, these signals increased both types in PBW343 but CW-POX only in PBW644. Polyphenol oxidases were ABA-upregulated in PBW644 only. Under WS, these enzymes were maintained higher in PBW343. This study indicated that tolerant cultivar under WS contained sufficient endogenous ROS/NO signalling to which susceptible cultivar lacked but showed improvement on exogenous applications. Secondly, tolerant cultivar was using less phenolic activity under WS which could be due to the presence of sufficient levels of primary antioxidants.
Authors:Raheem Shahzad, Muhammad Waqas, Abdul Latif Khan, Khadija Al-Hosni, Sang-Mo Kang, Chang-Woo Seo and In-Jung Lee
Bacterial endophytes from the phyllosphere and rhizosphere have been used to produce bioactive metabolites and to promote plant growth. However, little is known about the endophytes residing in seeds. This study aimed to isolate and identify seed-borne bacterial endophytes from rice and elucidate their potential for phytohormone production and growth enhancement. The isolated endophytes included Micrococcus yunnanensis RWL-2, Micrococcus luteus RWL-3, Enterobacter soli RWL-4, Leclercia adecarboxylata RWL-5, Pantoea dispersa RWL-6, and Staphylococcus epidermidis RWL-7, which were identified using 16S rRNA sequencing and phylogenetic analysis. These strains were analyzed for indoleacetic acid (IAA) production by using GC-MS and IAA was found in the range of 11.50 ± 0.77 μg ml−1 to 38.80 ± 1.35 μg ml−1. We also assessed the strains for plant growth promoting potential because these isolates were able to produce IAA in pure culture. Most of the growth attributes of rice plants (shoot and root length, fresh and dry biomass, and chlorophyll content) were significantly increased by bacterial endophytes compared to the controls. These results show that IAA producing bacterial endophytes can improve hostplant growth traits and can be used as bio-fertilizers.
Authors:P. Motallebi, S. Tonti, V. Niknam, H. Ebrahimzadeh, A. Pisi, P. Nipoti, M. Hashemi and A. Prodi
Fusarium culmorum is a soilborne fungal pathogen, agent of crown and root rot disease (FCRR), responsible of major economic losses in wheat plants. This host—pathogen interaction, following methyl jasmonate (MeJA) application at the beginning of the necrotrophic stage of infection, has not been previously studied at molecular level. In this study, using real-time quantitative PCR, the emerging role of MeJA in the basal resistance of two bread wheat cultivars against F. culmorum has been investigated. MeJA treatment was dispensed 6 hours after pathogen inoculation (6 hai) to detect the defense response at the beginning of the necrotrophic stage. The expression of phenylalanine ammonia-lyase (PAL), lipoxygenase (LOX), cytochrome P450 (CYP709C1) genes and of some pathogenesis related (PR) genes, including PR3, PR4 and PR9, was examined in both root and crown tissues of the susceptible wheat cultivar Falat and the tolerant cultivar Sumai3. The pathogen responsive defense genes were induced in both cultivars, with a higher level of induction in Sumai3 than in Falat. MeJA treatment reduced the symptoms in cv Falat, whereas no significant effects have been detected in cv Sumai3. In fact, MeJA treatment caused a striking difference in defense gene induction. The genetic change was present in root and crown tissues of both wheat cultivars, demonstrating a systemic signaling pathway. The chemically induced protection correlated with induction of the F. culmorum-responsive genes supports a possible role of jasmonate signaling in regulating basal resistance in wheat–F. culmorum interaction.
Authors:Ankit Kumar Chauhan, Dinesh Kumar Maheshwari and Vivek K. Bajpai
In a multivalent approach to discover new antimicrobial substance, a total of 160 Bacilli were isolated from termitarium soil, characterized on the basis of their morphological and physiological characters and screened for their antimicrobial activity by agar well diffusion method against certain drug resistant pathogenic bacteria such as Staphylococcus aureus, Methicillin resistant Staphylococcus aureus and common food contaminating bacteria Listeria monocytogenes. After preliminary screening, sixteen isolates showed inhibitory activity against test pathogens. Among them Bacillus isolate TSH58 exhibited maximum inhibitory activity against MRSA, Staphylococcus aureus and Listeria monocytogenes. Based on morphological, physiological, biochemical and 16S rDNA characteristics isolate TSH58 was identified as a member of the Bacillus cereus species group. Various nutrient sources and culture conditions were optimized, the partially purified antimicrobial metabolite was subjected to various treatments such as heat, pH and proteolytic enzymes. Complete loss in the activity observed when the crude metabolite was treated with proteolytic enzymes suggesting its proteinaceous nature and termed as bacteriocin like inhibitory substance (BLIS). Minimal inhibitory concentration of the partially purified bacteriocin determined by microtiter plate assay was 80 μg/ml for MRSA and 40 μg/ml for L. monocytogenes. Tricine SDS PAGE analysis revealed that the partially purified bacteriocin produced by the Bacillus strain TSH58 had an apparent molecular weight of about 4.0 KDa.
Authors:Gábor Máté, Dominika Kovács, Zoltán Gazdag, Miklós Pesti and Árpád Szántó
The present study investigated the linalool (Lol)-induced effects in acute toxicity tests in the human pathogen Candida albicans (C. albicans). Lol treatments induced reduced germ tube formation of the pathogen, which plays a crucial role in the virulence. In comparison with the untreated control, the exposure of 107 cells ml−1 to 0.7 mM or 1.4 mM Lol for one hour induced 20% and 30% decrements, respectively, in the colony-forming ability. At the same time, these treatments caused dose-dependent decrease in the levels of superoxide anion radical and total reactive oxygen species, while there was 1.5 and 1.8-fold increases in the concentrations of peroxides and lipid peroxides, respectively, indicating oxidative stress induction in the presence of Lol. Lol treatments resulted in different adaptive modifications of the antioxidant system. In 0.7 mM-treated cells, decreased specific activities of superoxide dismutase and catalase were detected, while exposure to 1.4 mM Lol resulted in the up-regulation of catalase, glutathione reductase and glutathione peroxidases.
Authors:J. Schmid, K. Hoenes, M. Rath, P. Vatter, B. Spellerberg and M. Hessling
In this study, the photoinactivation of Legionella by visible light is investigated. The success of this approach would offer new prospects for technical water disinfection and maybe even for therapeutic measures in cases of Legionella infections. Therefore, Legionella rubrilucens was dispensed on buffered charcoal yeast extract medium agar plates and illuminated with different doses of violet light generated by 405 nm light-emitting diodes (LEDs). A strong photoinactivation effect was observed. A dose of 125 J/ cm2 reduced the bacterial concentration by more than 5 orders of magnitude compared to Legionella on unirradiated agar plates. The necessary dose for a one log-level reduction was about 24 J/cm2. These results were obtained for extracellular L. rubrilucens, but other Legionella species may exhibit a similar behavior.
The invasive gelechiid moth, potato tuberworm Phthorimaea operculella (Zeller, 1873) was first recorded in Hungary (Komló, Baranya County) and Northern Croatia (Lug, Osijek-Baranja County) in December 2015. This quarantine species has not been reported from Hungary so far and it was known in Croatia only from the coastal region. The occurrence of Ph. operculella in the Carpathian basin is of great concern as this invader is able to cause negative impacts on the Hungarian potato cultivation. This occurrence of the species is one of the northernmost data in Europe so far.
Authors:A. Sattar, M.A. Cheema, T. Abbas, A. Sher, M. Ijaz, M.A. Wahid and M. Hussain
Late planting of wheat in rice-wheat cropping system is perhaps one of the major factors responsible for low crop yield. The main cause of reduction in yield is due to supra-optimal conditions during the reproductive growth. High temperature during reproductive phase induces changes in water relations, decreases photosynthetic rate, and transpiration rate, stomatal conductance and antioxidative defence system. Silicon (Si), being a beneficial nutrient not only provides significant benefits to plants growth and development but may also mitigate the adversities of high temperature. A field study was conducted at Agronomic Research Area of University of Agriculture; Faisalabad, Pakistan to assess the performance of late sown wheat with the soil applied Si. Experiment was comprised of three sowing dates; 10th Nov (normal), 10th Dec (late), 10th Jan (very late) with two wheat varieties (Sehar-2006 and Faisalabad-2008), and an optimized dose of Si (100 mg per kg soil), applied at different growth stages (control, crown root, booting and heading). Results indicated that 100 mg Si per kg soil at heading stage offset the negative impact of high temperature and induced heat tolerance in late sown wheat. Silicon application improved 34% relative water contents (RWC), 30% water potential, 26% osmotic potential, 23% turgor potential and 21% photosynthetic rate, and 32% transpiration rate and 20% stomatal conductance in wheat flag leaf than control treatment. Further it was observed that Si application preventing the oxidative membrane damage due to enhanced activity of antioxidant enzymes, i.e. 35% superoxide dismutase (SOD) and 38% catalase (CAT). In conclusion results of this field study demonstrated that soil applied Si (100 mg per kg soil) at heading stage enhanced all physiological attributes of wheat flag leaf. Which in turn ameliorated the adverse effects of high temperature in late sown wheat. Study depicted that Si can be used as a potential nutrient in order to mitigate the losses induced by high temperature stress.
Authors:Orsolya Orbán-Gyapai, Peter Forgo, Judit Hohmann and Andrea Vasas
In the course of our pharmacological screening of Polygonaceae species occurring in the Carpathian Basin the extracts prepared from the roots of Rumex thyrsiflorus showed promising antiproliferative, xanthine oxidase inhibitory and antibacterial activities. The present work deals with the isolation of compounds from the root of the plant. After multistep separation process, four compounds were obtained from the n-hexane, chloroform and ethyl acetate soluble fractions of the methanol extract of the root. The structures of the isolated compounds were determined as 1-palmitoylglycerol, β-sitosterol, (–)-epicatechin, and procyanidin B5.
Authors:Masahiko Suzuki, Arihiro Iwasaki, Kiyotake Suenaga and Hisashi Kato-Noguchi
Tithonia diversifolia (Hermsl.) A. Gray is a perennial invasive plant and spreads quickly in the invasive areas. The extracts of T. diversifolia were found to be toxic to several crop plant species such as rice, maize, sorghum, lettuce and cowpea, and several putative allelopathic substances were identified. However, there is limited information available for the effects of T. diversifolia on wild plants including weed plant species. We investigated the allelopathic potential of T. diversifolia extracts on weed plants, and searched for phytotoxic substances with allelopathic activity. An aqueous methanol extract of T. diversifolia leaves inhibited the growth of weed plants, Lolium multiflorum Lam., Phleum pretense L., Echinochloa crus-galli (L.) Beauv. The extract was then purified by several chromatographic runs and a phytotoxic substance with allelopathic activity was isolated and identified by spectral analysis as tagitinin C. The substance inhibited the growth of Lolium multiflorum, Phleum pratense and Echinochloa crus-galli at concentrations greater than 0.1 – 0.3 mM. The present results suggest that T. diversifolia may possess allelopathic potential on weed plants and tagitinin C may be responsible for the allelopathic effects of T. diversifolia. The allelopathic potential of T. diversifolia may contribute to its invasive characteristics.
A laboratory experiment was conducted at the Biocontrol laboratory, Coconut Research Station, Aliyarnagar to study the life table parameters of Bracon brevicornis Wesmael, a parasitoid of the coconut blackheaded caterpillar, Opisina arenosella Walker on its established laboratory host, Corcyra cephalonica Stainton. Studies at 28.3±0.1 °C and 59.6±0.6% r.h. revealed that the net reproductive rate (Ro) of B. brevicornis was 39.52 females/female when reared on C. cephalonica larvae. The precise generation time (T) was 13.33 days. The intrinsic rate of natural increase (rm) was 0.2758 which was slightly higher than the innate capacity for increase (rc=0.2504). The weekly multiplication rate was 6.893 numbers while 1561.83 females could be expected in the F2 generation. Higher net reproductive rate, coupled with shorter population doubling time of B. brevicornis indicate the efficacy of the parasitoid as a suitable candidate for the management of coconut black headed caterpillar, O. arenosella, its intended host under field conditions.
Authors:Abed Zahedi Bialvaei, Tala Pourlak, Mina Aghamali, Mohammad Asgharzadeh, Pourya Gholizadeh and Hossein Samadi Kafil
Bacterial antimicrobial resistance mediated by the production of extended-spectrum β-lactamases (ESBLs) is considered a major threat for treatment of Salmonella and Shigella infections. This study aimed to investigate antibiotic resistance patterns of Salmonella and Shigella spp. and presence of CTX-M from three teaching hospitals in Iran. In the present study, 58 clinical Shigella and 91 Salmonella isolates were recovered between 2009 and 2013 from 3 teaching hospitals in Iran. After culture and antimicrobial susceptibility testing, ESBL-positive isolates were subjected to further investigations. These included polymerase chain reaction (PCR) amplification and DNA sequencing of blaCTX-M-15 encoding plasmid. In both genera, high sensitivity to gentamicin and amikacin, but high resistance to ampicillin, tetracycline, and trimethoprim—sulfamethoxazole, was found. Molecular investigation showed that 31.8% isolates of Salmonella spp. and 34.48% isolates of Shigella spp. were CTX-M positive and all of them were also positive for ISEcpI. Protein translation, comparing with reference sequences, showed that all CTX-M isolates belong to CTX-M-15. The present study suggests that the resistance of ESBLs-producing Salmonella and Shigella spp. in Iran hospitals is very serious. Therefore, strategies to minimize the spread of ESBL-producing isolates should be implemented.
Authors:S. Sheoran, D. Raj, R.S. Antil, V.S. Mor and D.S. Dahiya
A long-term field experiment started in 1995 on Research Farm of Department of Soil Science, CCS Haryana Agricultural University Hisar (India) was selected to study the effects of organic manures and chemical fertilizers on productivity, seed quality and nutrient use efficiency of wheat under pearl millet-wheat cropping system. The organic manures (15 Mg FYM, 5 Mg poultry manure and 7.5 Mg pressmud) were applied alone and in combination with fertilizers (150 kg N + 30 kg P2O5 ha−1) and compared with chemical fertilizers applied alone (150 kg N + 60 kg P2O5 ha−1 and 75 kg N + 30 kg P2O5 ha−1). The results showed that the application of organic manures in combination with N and P fertilizers significantly increased all yield attributes, i.e. plant height, number of tillers/m row length, spike length, number of grains/spike. Higher grain yield of wheat (61.4, 57.4 and 62.7 q ha−1) was observed when recommended dose of N and half of P was applied in conjunction with FYM, poultry manure and pressmud, respectively. Grain yield of wheat increased by 13.5, 6.1 and 15.9%, respectively, under same treatments when compared with recommended dose of N and P fertilizers. Among the organic manures, highest yield (32.9 q ha−1) was obtained with pressmud application. However, application of organic manures alone resulted in poor yield and even lower than 50% recommended dose of N and P fertilizer. All the seed quality parameters (standard germination, shoot length, root length, seedling dry weight, seedling vigour index-I and -II) improved with the combined application of organic manures and chemical fertilizers as compared to their individual application. The partial factor productivity of N and P increased with combined application organic manures and chemical fertilizer as compared to chemical fertilizers applied alone, however, nutrient harvest index and their utilization efficiency decreased with combined application of organic manures and fertilizers as compared to their individual application.
Authors:L.V. Shchukina, T.A. Pshenichnikova, A.K. Chistyakova, E.K. Khlestkina and A. Börner
Various milling parameters, wet gluten content and key dough properties were analyzed for two sister lines of bread wheat with Ae. markgrafii introgressions in genetic background of cultivar Alcedo carrying a set of sub-chromosomal alien segments on chromosomes 2AS, 2BS, 3BL, 4AL and 6DL. The lines revealed higher grain vitreousness, larger particle size of flour, and higher wet gluten content in grain compared to cv. Alcedo. The flour from these lines also showed excellent water absorption and developed more resilient dough. The introgressions in the Alcedo genome caused no reduction in 1,000-grain weight. General improvement of the grain technological properties appears to be the result of introgressions into 2AS, 2BS and 3BL chromosomes. Coincidence of locations of Ae. markgrafii introgressions in chromosome with the QTLs positions for technological traits, revealed in bread wheat mapping populations, is discussed.
The potential effect of combined salicylic acid and fish flour to improve plant tolerance to salt stress was investigated. This pre-treatment improved the growth of wheat seedlings under salinity when compared to control (untreated wheat seedlings). Moreover, combined pre-treatment improved significantly phenylalanine ammonia lyase (PAL) and peroxidase (POD) enzyme activities, also phenolic-flavonoid content in the shoots of salt stressed seedlings. One of the most important consequences of increase in salt stress is the oxidative tissue damage. In our study, salt stress increased lipid peroxidation levels (LPO) and also the loss of chlorophylls levels during stress might also be related to photo-oxidation resulting from oxidative stress. Whereas phenylalanine ammonia-lyase (PAL) activities of wheat shoots increased by a 2.1-fold under salt stress, the activities of shoots grown from seeds primed with salicylic acid and fish flour (SA + FF) increased by a 4-fold for 0.05 mM SA + FF, 4.8- fold for 0.1 mM SA + FF and 3.7-fold for 2.5 mM SA + FF combined pre-treatment under salt stress. Also, the combined salicylic acid + fish flour primed seedlings showed higher content of the scopoletin, and salicylic, syringic, vanilic and gallic acids under both salt and nonsalinity stress conditions.
Authors:Markus M. Heimesaat, Ursula Grundmann, Marie E. Alutis, André Fischer and Stefan Bereswill
Host immune responses are crucial for combating enteropathogenic infections including Campylobacter jejuni. Within 1 week following peroral C. jejuni infection, secondary abiotic IL-10−/− mice develop severe immunopathological sequelae affecting the colon (ulcerative enterocolitis). In the present study, we addressed whether pathogen-induced pro-inflammatory immune responses could also be observed in the small intestines dependent on the innate receptor nucleotide-oligomerization-domain-protein 2 (Nod2). Within 7 days following peroral infection, C. jejuni stably colonized the gastrointestinal tract of both IL-10−/− mice lacking Nod2 (Nod2−/− IL-10−/−) and IL-10−/− controls displaying bloody diarrhea with similar frequencies. Numbers of apoptotic and regenerating epithelial cells increased in the small intestines of C. jejuni-infected mice of either genotype that were accompanied by elevated ileal T and B lymphocyte counts. Notably, ileal T cell numbers were higher in C. jejuni-infected Nod2−/− IL-10−/− as compared to IL-10−/− counterparts. Furthermore, multifold increased concentrations of pro-inflammatory cytokines including IFN-γ, TNF, and MCP-1 could be measured in small intestinal ex vivo biopsies derived from C. jejuni-infected mice of either genotype. In conclusion, C. jejuni-induced pro-inflammatory immune responses affected the small intestines of both Nod2−/− IL-10−/− and IL-10−/− mice, whereas ileal T lymphocyte numbers were even higher in the former.
Authors:M. Oyekunle, A. Menkir, H. Mani, G. Olaoye, I.S. Usman, S.G. Ado, U.S. Abdullahi, H.O. Ahmed, L.B. Hassan, R.O. Abdulmalik and H. Abubakar
Genotype × environment interactions complicate selection of superior genotypes for narrow and wide adaptation. Eighteen tropically-adapted maize cultivars were evaluated at six locations in Nigeria for 2 yrs to (i) identify superior and stable cultivars across environments and (ii) assess relationships among test environments. Environment and genotype × environment interactions (GEI) were significant (P < 0·05) for grain yield. Environments accounted for 63.5% of the total variation in the sum of squares for grain yield, whereas the genotype accounted for 3.5% and GEI for 32.8%. Grain yield of the cultivars ranged from 2292 kg ha–1 for DTSTR-W SYN2 to 2892 kg ha−1 for TZL COMP4 C3 DT C2 with an average of 2555 kg ha−1. Cultivar DT SYN2-Y had the least additive main effect and multiplicative interaction (AMMI) stability value of 7.4 and hence the most stable but low-yielding across environments. AMMI biplot explained 90.5% and classified cultivars and environments into four groups each. IWD C3 SYN F3 was identified as the high-yielding and stable cultivar across environments. ZA15, ZA14, BK14, BK15 and IL15 had environment mean above the grand mean, while BG14, BG15, LE14, LE15, IL14, LA14 and LA15 had mean below the grand mean. ZA, BK, BG, LE and LA were found to be consistent in ranking the maize cultivars. However, Zaria, Birnin Kudu, and Ilorin were identified as the best test locations and could be used for selecting the superior maize cultivars. The identified high-yielding and stable cultivar could be further tested and promoted for adoption to contribute to food insecurity in Nigeria.
The objective of this work was to determine the change for straw production, carbon and ash content in vegetative tissues through ten cycles of recurrent selection in bread wheat, evaluated under tilled (CT) and non-tilled (NT) soils. Twenty-four wheat genotypes, four for each one of the 0, 2, 4, 6, 8 and 10 cycles of recurrent selection (RS), were used in this study. Experiments were established during two successive seasons. Ash content was expressed on dry mass basis. To estimate the carbon content, we based our calculation on the assumption that organic matter is 50% carbon. Straw dry weight was measured. For each trait, a linear mixed model (regression) was fitted to the experimental data. In response to the number of selection cycles, the ash content percentage increased under CT and decreased under NT. Carbon content decreases under CT, but increases under NT. The sequestered straw carbon and the straw production significantly decrease under CT meanwhile there was no change under NT. The observed increase for straw ash content would be related to the highest rate of transpiration in the more advanced recurrent selection cycles. Consistent with these results, the percentage of straw carbon content decreased because of the mobilization of reserves from the stems and leaves to the grains.
During 2014 and 2015, four species of bark beetles (Coleoptera: Curculionidae: Scolytinae), belonging to a single genus Scolytus Geoffroy, 1762, were collected from elm trees in East Azarbaijan province, northwestern Iran. They were Scolytus pygmaeus (Fabricius, 1787), Scolytus ensifer Eichhoff, 1881, Scolytus ecksteini Butovitsch, 1929, and Scolytus kirschii fasciatus Reitter, 1890. All of them represent new records for East Azarbaijan province.
Authors:M. Javadzadeh, M. Taghizadeh and A. Hosseini-Gharalari
The European Mole Cricket, Gryllotalpa gryllotalpa (Orthoptera: Gryllotalpidae), is a key pest of several crops in different regions of the world, damaging seedlings, roots and tubers. The efficacy of fipronil (Regent ® GR 0.2%) @ 2, 2.5 and 3 g/m2 along with toxic bait of carbaryl (EC 85%)@ 20 g/m2 were assessed against this pest in the field based on a completely randomized block design. Based on Henderson-Tilton formula, on the third day after treatment, the efficacy of fipronil @ 2, 2.5 and 3 g/m2 and carbaryl bait was 16%, 30%, 47% and 53%, respectively; while on the third day after treatment, the efficacy was 22%, 48%, 64% and 81%, respectively. At present, carbaryl application is banned in Iran; therefore, fipronil can be a suitable substitute for this insecticide.
Authors:M. Javadzadeh, A. Sheikhi-Garjan and A. Hosseini-Gharalari
The confused flour beetle, Tribolium confusum, is a key pest of stored products such as wheat and flour. For decades, organophosphorus compounds, such as malathion and pirimiphos-methyl, have been applied against stored-product pests. In this research, susceptibility of different populations of T. confusum, collected from silos at different locations of Iran, against malathion (EC 57%), was studied in the laboratory, based on a completely randomized design. Based on pre-tests, the Bioassay Index Dose was estimated as 2 g a.i./m2. Out of 23 populations, 2 populations from Bandar-Abbas region were resistant populations against malathion (9.72% and 67.2% mortality), while one population from Khomein region was moderately resistant (86.08% mortality), and the rest of the population were susceptible to malathion (95.71% to 100% mortality). Therefore, in warm locations of Iran, where this pest has evolved resistance against malathion, other control measures shall be considered.
Authors:S. Mahmood, I. Hussain, A. Ashraf, A. Parveen, S. Javed, M. Iqbal and B. Afzal
Alkaline and acidic pH of soil limit crop yield. Products of phenylpropanoid pathway play a key part in plant abiotic stress tolerance. It was aimed to assess efficacy of tyrosinepriming for activation of enzyme involved in phenolic accumulation induction of pH tolerance in maize seedlings. Seeds of two maize cultivars, namely Sadaf (pH tolerant) and S-2002 (pH sensitive), were grown under three pH levels (3, 7 and 11). Eight and twelve days old seedlings were harvested and parted into roots and shoots for the assessment of growth, enzymatic and non-enzymatic antioxidants. PAL activity was directly correlated with total soluble phenolics, flavonoids, growth and seedling vigour. Lower accumulation of phenolics and PAL activity in the pH sensitive (S-2002) cultivar indicated greater oxidative damage caused by pH extremes. Priming improved antioxidative potential by enhancing PAL activity and phenolics accumulation and hence increased growth in maize seedlings.
Authors:D. Soresi, D. Zappacosta, A. Garayalde, I. Irigoyen, J. Basualdo and A. Carrera
Langdon(Dic-3A)-10 line carrying the QTL Qfhs.ndsu-3AS from T. turgidum ssp. dicoccoides that confers Type II resistance to Fusarium head blight (FHB) was crossed with Argentinean durum wheat cultivars. F4 progeny were screened with the microsatellite locus Xgwm2, tightly linked to the Qfhs.ndsu-3A region. Reaction of these plants and parents to FHB was evaluated at 7, 14 and 21 days post-inoculation (dpi) with F. graminearum; severity (% symptomatic spikelets/spike) and AUDPC (area under disease progress curve) were calculated. F4 progeny carrying the resistance allele in heterozygous or in homozygous condition showed significantly lower scab damage at 21 dpi and slower progress of disease than cultivated parents. Our results indicate that the resistance Qfhs.ndsu-3AS has a stable dominance expression in genetic backgrounds of durum cultivars and demonstrate that the linked microsatellite is an effective molecular tool for resistance screening. This work offers valuable information for Qfhs.ndsu-3AS utilization in wheat breeding programs.
Authors:C. Wehenkel, A. Reyes-Martínez, J. H. Martínez-Guerrero, C. Pinedo-Alvarez and C. A. López-Sánchez
Bird migration constitutes a redistribution of bird diversity that radically changes the composition of the bird community worldwide. It comprises about 19% of the world’s bird species. Several studies have indicated that changes in avian community structure and differences in bird richness in different seasons are mainly driven by seasonality and by winter harshness, and that the associated costs increase with the distance involved. Western Mexico is an important wintering area for most passerines that breed in western North America, and that travel long on the long-distance Central and Pacific migration routes. In this study, we examined bird species richness and diversity during the breeding and wintering seasons in the Central Sierra Madre Occidental (SMO), North Durango (Mexico) in relation to i) tree species diversity, ii) tree dimension, iii) forest stand density and site quality, iv) density and dimension of snag trees, and v) various climate variables. The overall aim of the study was to determine how the observed associations between bird species diversity and variables i-v are affected by the season considered (breeding or wintering). The diversity of bird species in the breeding season was not affected by any of the climate and forest stand variables considered. In contrast, bird species diversity in the wintering season was significantly and weakly to moderately associated with climate variables, tree species diversity and stand density, although not with density or dimension of snag trees. Bird species diversity was higher at lower elevations and in drier and warmer locations of the SMO. The association detected is therefore mainly a local migratory phenomenon.
Authors:F. J. Fernandez-Maldonado, J. R. Gallego, A. Valencia, M. Gamez, Z. Varga, J. Garay and T. Cabello
Cannibalism is a common phenomenon among insects. It has raised considerable interest both from a theoretical perspective and because of its importance in population dynamics in natural ecosystems. It could also play an important role from an applied perspective, especially when using predatory species in biological control programmes. The present paper aims to study the cannibalistic behaviour of Nabis pseudoferus Remane and the functional response of adult females. In a non-choice experiment, adult females showed clear acceptance of immature conspecifics as prey, with relatively high mortality values (51.89 ± 2.69%). These values were lower than those occurring for heterospecific prey, Spodoptera exigua Hübner, under the same conditions (80.00 ± 2.82%). However, the main result was that the rate of predation on heterospecific prey was reduced to 59.09 ± 7.08% in the presence of conspecific prey. The prey-capture behaviour of adult females differed when they hunted conspecific versus heterospecific prey. This was shown in the average handling time, which was 23.3 ± 3.3 min in the first case (conspecific) versus 16.6 ± 2.5 min in the second (heterospecific). Furthermore, the values increased in the former case and declined in the latter according to the order in which the prey were captured. The difference in handling time was not significant when adjusting the adult female functional response to conspecific nymphs. We argue that these results likely indicate risk aversion and a fear of reprisal among conspecifics.
Authors:Y. González, G. Aragón, A. Benítez and M. Prieto
Altitudinal gradients involve macroclimatic changes that can affect the diversity of several organisms. We tested the effects of elevation and small-scale variables on the diversity and composition of terricolous communities (lichens and bryophytes) in five páramos in southern Ecuador. The altitudinal range considered (from 2700 to 4000 m a.s.l.) is associated with changes in rainfall, temperature and irradiance. At each páramo, forty 40 x 40 cm2 sample plots were randomly selected in similar areas of vegetation (grass páramo) and conservation status. The presence/absence and cover of lichens and bryophytes were recorded in 200 sample plots. A total of 90 species (46 lichens and 44 bryophytes) were identified. Our results showed that total species richness, lichen and bryophyte richness, Simpson’s inverse and Shannon’s index were related to elevation and slope. Nevertheless, the response to elevation was dependent on the organism considered. Thus, meanwhile lichens had their maximum richness at the highest elevation (3930 m a.s.l.), bryophytes had a maximum peak at middle elevation (3300 m a.s.l.). Species composition also differed significantly among the five páramos, especially in bryophytes. We conclude that differences in the elevation of these páramos and small-scale variables such as slope significantly affect the diversity and composition of terricolous communities.
Authors:G. Ónodi, Gy. Kröel-Dulay, E. Kovács-Láng, P. Ódor, Z. Botta-Dukat, B. Lhotsky, S. Barabás, J. Garadnai and M. Kertész
Aboveground plant biomass is one of the most important features of ecosystems, and it is widely used in ecosystem research. Non-destructive biomass estimation methods provide an important toolkit, because the destructive harvesting method is in many cases not feasible. However, only few studies have compared the accuracy of these methods in grassland communities to date. We studied the accuracy of three widely used methods for estimation of aboveground biomass: the visual cover estimation method, the point intercept method, and field spectroscopy. We applied them in three independent series of field samplings in semi-arid sand grasslands in Central Hungary. For each sampling method, we applied linear regression to assess the strength of the relationship between biomass proxies and actual aboveground biomass, and used coefficient of determination to evaluate accuracy. We found no evidence that the visual cover estimation, which is generally considered as a subjective method, was less accurate than point intercept method or field spectroscopy in estimating biomass. Based on our three datasets, we found that accuracy was lower for the point intercept method compared to the other two methods, while field spectroscopy and visual cover estimation were similar to each other in the semi-arid sand grassland community. We conclude that visual cover estimation can be as accurate for estimating aboveground biomass as other approaches, thus the choice amongst the methods should be based on additional pros and cons associated with each of the method and related to the specific research objective.
Authors:K. T. Tolonen, A. Vilmi, S. M. Karjalainen, S. Hellsten and J. Heino
Modern biodiversity research focuses on multiple diversity facets because different indices may describe different ecological and environmental processes, as well as the effects of varied disturbances of natural and anthropogenic origins. We investigated littoral macroinvertebrate diversity in a large boreal lake system and specifically explored congruence of indices within and between the three diversity facets: species diversity, functional diversity and taxonomic distinctness. First, we found that the indices of taxonomic distinctness were the most sensitive indicators of eutrophication. Second, we observed that most correlations between the indices within the same diversity facet, and between the indices of functional and species diversity, were relatively strong. However, the indices of taxonomic distinctness (Δ+ and Λ+) were weakly associated with other metrics of diversity, emphasising the importance of taxonomic distinctness as a complementary dimension of biodiversity. Therefore, our observations support the importance to examine multiple facets for mapping biodiversity or for assessing the effects of anthropogenic disturbances on biological communities.
The influence of edge proximity on woodland plants is a well-established research area, yet the influence of dual edge exposure has rarely been investigated. This novel research aims to establish whether proximity to two edges has any additive influence on Ancient Woodland Indicator (AWI) species presence relative to proximity to a single edge. Several AWI species are threatened and thus specific conservation priorities, while Ancient Semi-Natural Woodland (ASNW) itself is often highly fragmented: almost half of remnant patches are less than 5 ha, which increases the potential for dual edge effects. Here, systematic mapping of herbaceous AWI species was conducted in 310 vegetation plots in two formerly-connected ASNW fragments in South-West England. Linear regression modelling revealed that distance to nearest edge and distance to second nearest edge were both univariately positively correlated with AWI species richness. After distance from nearest edge was entered into a multivariate model first, distance from second edge was entered in a second optional step after meeting stepwise criteria. The resultant multivariate model was more significant, and explained more variance, than either variable in isolation, indicating an additive effect of dual edge exposure. Likewise, binary logistic regression modelling showed presence of individual AWI species (Anemone nemorosa, Hyacinthoides non-scripta, Lamiastrum galaeobdolon and Paris quadrifolia) was significantly related not only to distance from the nearest and second nearest edges in isolation, but significantly more strongly by the additive effect of distance from both edges in a single model. We discuss the implications of these findings from community ecology and conservation perspectives.
Authors:M. Petrášová-Šibíková, T. Bacigál and I. Jarolímek
The present study focuses on how spatial patch characteristics, such as patch area, shape and isolation, affect the natural species composition of hardwood floodplain forests. The natural species composition is defined according to species groups obtained using phytocoenological methods. The aim of the study was to establish the relationship between fragmentation indices and the number and proportion of species in each functional species group stated in this paper. This study is based on a dataset of 118 phytocoenological relevés sampled using the standard methodology of the Zürich-Montpellier School, ordered within the suballiance Ulmenion (mixed oak-elm-ash forests along the great rivers). The study area is situated in Central Europe, in the northern part of the Pannonian biogeographic region. The digital map of hardwood floodplain forests was rasterized to 25 m cell size. The FRAGSTATS software was used to obtain fragmentation indices, and generalised linear models tested the influence of forest patch fragmentation indices on species composition. Our analyses confirm that large hardwood floodplain forests are essential for natural species composition conservation, and that large fragment areas are highly susceptible to non-native species penetration. We also determined that small, compact fragments contain very valuable remnants of well-preserved natural hardwood floodplain forests with a high proportion of specialised Ulmenion species. However, disruption to hardwood floodplain forest natural borders engenders a greater threat to its natural species composition than decline in patch area, because disruption results in increased Shape index, increased contact with the surrounding environment, greater edge effect and a higher proportion of alien species in the forest community.
We studied a benthic invertebrate assemblage of a stream that passes through pristine, rural, suburban and urban areas of a municipality located in southeastern Brazil to investigate a possible relationship between this assemblage structure and urbanization. The environmental variables and fauna structure were analyzed in a spatial and temporal scale, sampling the four sites in a dry and wet season. We found a clear spatial pattern, with higher similarity between sites from rural and suburban area that presented intermediate environmental characteristics. The pristine site showed in both seasons the lowest values of alkalinity and fecal coliform. On the other hand, the site located in the urban area showed the lowest concentration of dissolved oxygen and higher of suspended solids, ammonia and fecal coliform. The extreme values of these three variables occurred in the wet season, probably related to the high rainfall values. The benthic invertebrate fauna structure followed the same longitudinal and seasonal pattern found for the environmental variables. The site in urban area showed the lowest richness, diversity and evenness, with a dominance of two groups resistant to adverse environmental conditions (Oligochaeta and Orthocladiinae) and absence of more sensitive groups (Coleoptera, Ephemeroptera and Trichoptera). The increase drag of the substrate and associated invertebrates can be responsible for the lower abundance and richness observed in the wet season. The environmental variables that best defined the differentiation between sites (dissolved oxygen, organic suspended solids and fecal coliform) related directly to urbanization effects, like dump effluents and removal of riparian vegetation.
Authors:P. Biella, J. Ollerton, M. Barcella and S. Assini
Conservation of species is often focused either only on those that are endangered, or on maximising the number recorded on species lists. However, species share space and time with others, thus interacting and building frameworks of relationships that can be unravelled by community-level network analysis. It is these relationships that ultimately drive ecosystem function via the transfer of energy and nutrients. However interactions are rarely considered in conservation planning. Network analysis can be used to detect key species (“hubs”) that play an important role in cohesiveness of networks. We applied this approach to plant-pollinator communities on two montane Northern Apennine grasslands, paying special attention to the modules and the identity of hubs. We performed season-wide sampling and then focused the network analyses on time units consistent with plant phenology. After testing for significance of modules, only some modules were found to be significantly segregated from others. Thus, networks were organized around a structured core of modules with a set of companion species that were not organized into compartments. Using a network approach we obtained a list of important plant and pollinator species, including three Network Hubs of utmost importance, and other hubs of particular biogeographical interest. By having a lot of links and high partner diversity, hubs should convey stability to networks. Due to their role in the networks, taking into account such key species when considering the management of sites could help to preserve the greatest number of interactions and thus support many other species.
Although overlap of communities is a key issue in studies ranging from community ecology to biogeography, a clear definition of community overlap and related terms hinder the development of the field. The absence of a unified terminology is remarkable even when the overlap of a pair or multiple communities is characterized. As a remedy, I suggest a definition of community overlap and two measures of it (number of overlapping species and total overlap size). Although both measures quantify different aspects of community overlap, in studying pairs of communities they yield identical results. The present findings demonstrate the need for a unified terminology in research on community overlap as well as for pairwise and multiple measures for quantifying the phenomenon.
Authors:M.C. Hingee, D. Eamus, D.W. Krix, S. Zolfaghar and B.R. Murray
Groundwater-dependent ecosystems (GDEs) are threatened by over-extraction of groundwater for human needs across the world. A fundamental understanding of relationships between naturally occurring gradients in depth-to-groundwater (DGW) across landscapes and the ecological properties of vegetation assemblages is essential for effective management of the impacts of groundwater extraction. Little is known, however, about relationships between DGW and the ecology of mesic woodlands in GDEs. Here, we investigated relationships between a naturally occurring DGW gradient and plant species composition, richness and abundance in mesic Eucalyptus woodlands of eastern Australia. Across 16 sites varying in DGW from 2.4 m to 43.7 m, we found that plant species composition varied significantly in relation to DGW, independently of a range of 14 physical and chemical attributes of the environment. Nine understorey species, representing only 7% of the pool of 131 plant species, were identified as contributing to up to 50% of variation in species composition among the study sites. We suggest this dominant pattern driver in the understorey is explained by differential abilities among understorey species in their ability either to tolerate extended dry conditions at deeper DGW sites during periods of low rainfall, or to withstand periodically waterlogged conditions at shallow sites. Plant species richness and total plant abundance (a measure of plant productivity) were not significantly and independently related to DGW or any of the other 14 environmental attributes. Our finding for a direct relationship between DGW and plant species composition provides important reference information on the ecological condition of these mesic woodlands in the absence of groundwater extraction. Such information is vital for setting ecological thresholds that ensure sustainable extraction of groundwater.
The metacommunity perspective has substantially advanced our understanding of how local (within community) and dispersal (between community) processes influence the assembly of communities. The increased recognition of dispersal processes makes it necessary to re-evaluate former views on community organization in different ecological systems and for specific organisms. Stream systems have long been considered from a linear perspective, in which local community organization was examined along the longitudinal profile, from source to mouth. However, the hierarchically branching (i.e. dendritic) structure of stream networks also significantly affects both local and regional scale community organization, which has just only recently been fully recognized by ecologists. In this review, I examine how the shift from a strictly linear to a dendritic network perspective influenced the thinking about the organization of fish metacommunities in stream networks. I argue that while longitudinal patterns in the structure of fish communities are relatively well known, knowledge is still limited about how the structure of the stream network ultimately affects the spatial and temporal dynamics of metacommunities. I suggest that scaling metapopulation models up to the metacommunity level can be useful to further our understanding of the spatial structure of metacommunities. However, this requires the delineation of local communities and the quantification of the contribution of dispersal to local community dynamics. Exploring patterns in diversity, spatial distribution and temporal dynamics of metacommunities is not easily feasible in continuous stream habitats, where some parts of the habitat network are exceptionally hard to sample representatively. Combination of detailed field studies with modelling of dispersal is necessary for a better understanding of metacommunity dynamics in stream networks. Since most metacommunity level processes are likely to happen at the stream network level, further research on the effects of stream network structure is needed. Overall, separation of the effect of dispersal processes from local scale community dynamics may yield a more mechanistic understanding of the assembly of fish communities in stream networks, which may also enhance the effectiveness of restoration efforts.
Authors:C. Ricotta, E. Ari, G. Bonanomi, F. Giannino, D. Heathfield, S. Mazzoleni and J. Podani
The increasing availability of phylogenetic information facilitates the use of evolutionary methods in community ecology to reveal the importance of evolution in the species assembly process. However, while several methods have been applied to a wide range of communities across different spatial scales with the purpose of detecting non-random phylogenetic patterns, the spatial aspects of phylogenetic community structure have received far less attention. Accordingly, the question for this study is: can point pattern analysis be used for revealing the phylogenetic structure of multi-species assemblages? We introduce a new individual-centered procedure for analyzing the scale-dependent phylogenetic structure of multi-species point patterns based on digitized field data. The method uses nested circular plots with increasing radii drawn around each individual plant and calculates the mean phylogenetic distance between the focal individual and all individuals located in the circular ring delimited by two successive radii. This scale-dependent value is then averaged over all individuals of the same species and the observed mean is compared to a null expectation with permutation procedures. The method detects particular radius values at which the point pattern of a single species exhibits maximum deviation from the expectation towards either phylogenetic aggregation or segregation. Its performance is illustrated using data from a grassland community in Hungary and simulated point patterns. The proposed method can be extended to virtually any distance function for species pairs, such as functional distances.
Authors:S. Figlan, T.A. Baloyi, T. Hlongoane, T.G. Terefe, H. Shimelis and T.J. Tsilo
Phenotypic and genotypic evaluation of wheat genetic resources and development of segregating populations are pre-requisites for identifying rust resistance genes. The objectives of this study were to assess adult plant resistance (APR) of selected wheat genotypes to leaf rust and stem rust and to develop segregating populations for resistance breeding. Eight selected Kenyan cultivars with known resistance to stem rust, together with local checks were evaluated for leaf rust and stem rust resistance at seedling stage and also across several environments. Selected diagnostic markers were used to determine the presence of known genes. All eight cultivars were crossed with local checks using a bi-parental mating design. Seedling tests revealed that parents exhibited differential infection types against wheat rust races. Cultivars Paka and Popo consistently showed resistant infection types at seedling stage, while Gem, Romany, Pasa, Fahari, Kudu, Ngiri and Kariega varied for resistant and susceptible infection types depending on the pathogen race used. The control cultivars Morocco and McNair consistently showed susceptible infection types as expected. In the field, all cultivars except for Morocco showed moderate to high levels of resistance, indicating the presence of effective resistance genes. Using diagnostic markers, presence of Lr34 was confirmed in Gem, Fahari, Kudu, Ngiri and Kariega, while Sr2 was present in Gem, Romany, Paka and Kudu. Seedling resistance gene, Sr35, was only detected in cultivar Popo. Overall, the study developed 909 F6:8 recombinant inbred lines (RILs) as part of the nested mating design and are useful genetic resources for further studies and for mapping wheat rust resistance genes.
Authors:Seda Sereflioglu, Burcu Seckin Dinler and Eda Tasci
In this paper, we describe the alleviated effects of alpha-tocopherol (α-T) on oxidative damage and its possible role as a signal transmitter in plants during salt stress. The results show that exogenously applied α-T under salt stress increased root length and weight, but reduced hydrogen peroxide (H2O2), superoxide anion radical (O2.—) and malondialdehyde (MDA) content in soybean roots. The proline content was reduced by α-T treatment. Interestingly, endogenous auxin (IAA) level was significantly increased after α-T application as compared to salt stress alone. Moreover, α-T reduced significantly superoxide dismutase (SOD) enzyme and isoenzyme activity but upregulated peroxidase (POX) 2, 3 and glutathione-s-transferase (GST) 1, 3 isoenzyme expression. However, ascorbate peroxidase (APX) enzyme activity was not affected at all. Consequently, the results show that α-T serves as a signal molecule under salinity from leaves to roots by increasing remarkably endogenous IAA levels and increasing partially antioxidant activity in roots.
Authors:O.Yu. Shoeva, E.I. Gordeeva, V.S. Arbuzova and E.K. Khlestkina
Plant secondary metabolites anthocyanins are considered to play a protective role. In bread wheat (Triticum aestivum L.), anthocyanins can be observed in both adult plants and seedlings. The aim of the current study was to investigate the putative role of anthocyanins present in grains and shoots with respect to the protection of seedlings against drought. For this purpose a set of near isogenic lines (NILs) differing in pericarp and coleoptile colour was used. Water stress was created by artificial shortage of moisture under laboratory conditions. Differences among the lines were observed in a way that the lines with dark-purple grains and coleoptiles (genotype Pp-D1Pp-D1Pp3Pp3Rc-A1Rc-A1Rc-D1Rc-D1) demonstrated a higher seedling drought tolerance than plants with uncoloured pericarp and lightpurple coleoptiles (pp-D1pp-D1pp3pp3Rc-A1Rc-A1rc-D1rc-D1). Furthermore, protection of the root system and the shoot was related with the presence of anthocyanins in grains and coleoptiles, respectively.
Authors:T. Kondratiuk, T. Beregova and L. Ostapchenko
The influence of culture fluid of a yeast-like fungus, melanin producer Pseudonadsoniella brunnea (Meripilaceae, Agaricomycotina) on pathogenic fungi of the genus Gibberella (anamorph of Gibberella fujikuroi, i.e.: Fusarium verticillioides) (Nectriaceae, Ascomycotina) is studied by using the agar diffusion method. The stable fungicidal effect of Ps. brunnea culture fluid on pathogenic fungi investigated found to be present. The diameter of the zones of absence of growth of test cultures of pathogenic fungi, those testified the fungicidal impact of Ps. brunnea culture fluid, found to be similar to the action of biocides belonging to the class of quaternary ammonium compounds (benzalkonium chloride).
Authors:R.H. Maich, M.E. Steffolani, J.A. Di Rienzo and A.E. León
The objective of the present investigation was to examine the relationships between agronomical behavior and grain quality along ten cycles of a recurrent selection program performed under rainfed condition. Twenty-four lines, four for each one of the 0, 2, 4, 6, 8 and 10 cycles of recurrent selection, were evaluated for two consecutive years (2011 and 2012). The experimental lines were evaluated under conventional (CT) and no tillage (NT) systems. Grain yield and grain weight were determined and harvest index and grain number estimated. Flour protein content, sodium dodecyl sulphate sedimentation (IS-SDS) and lactic acid SRC (LASRC) were considered as end-use quality predictive tests. The Spearman correlation coefficient was used to measure the relationships among yield, its components and grain quality parameters. Within the context of CT, flour protein content was negatively associated with all the agronomic variables. The IS-SDS has a negative association with the grain weight; meanwhile, LASRC associated positively with all the agronomic variables. When wheat was grown in NT, the relationship between IS-SDS and harvest index, like LASRC with all agronomic traits, was positive. Confining the discussion to the CT results, after ten cycles of recurrent selection the highest grain yield achieved was accompanied by a decrease in protein percentage. However, the decrease in the percentage of protein in more advanced selection cycles was offset by an improvement of its quality.
Authors:Farzaneh Garousi, Béla Kovács, Éva Domokos-Szabolcsy and Szilvia Veres
Supplement of common fertilizers with selenium (Se) for crop production will be an effective way to produce selenium-rich food and feed. The value of green pea seeds and forages as alternative protein source can be improved by using agronomic biofortification. Therefore, biological changes of green pea (Pisum sativum L.) and influences of inorganic forms of Se (sodium selenite and sodium selenate) at different concentrations on the accumulation of magnesium (Mg) and phosphorus (P) were investigated in greenhouse experiment. 3 mg kg−1 of selenite had positive effects to enhance photosynthetic attributes and decrease lipid peroxidation significantly. At the same time, Se accumulation increased in all parts of plant by increasing Se supply. Moreover, Mg and P accumulations were significantly increased at 3 mg kg−1 selenite and 1 mg kg−1 selenate treatments, respectively. By contrast higher selenite concentrations (≥30 mg kg−1) exerted toxic effects on plants. Relative chlorophyll content, actual photochemical efficiency of PSII (ФPSII) and Mg accumulation showed significant decrease while membrane lipid peroxidation increased. Thus, the present findings prove Se biofortification has positive effects on biological traits of green pea to provide it as a proper functional product.
Authors:M. Jawhar, A. Shoaib, M.I.E. Arabi and A. Aldaoude
Spot blotch, caused by Cochliobolus sativus, is an important barley disease which causes extensive grain yield losses worldwide. In order to investigate the molecular responses to the C. sativus infection, leaf transcriptome and proteome before and after fungus inoculation in a resistant barley genotype, were compared using cDNA-AFLP and 2-D PAGE techniques. A notable number of transcripts and proteins exhibiting significant differential accumulations were detected compared to the non-inoculated controls. Functional annotation of the transcripts and proteins revealed a wide range of pathways including cell wall fortification, metabolism, signal transduction and defence. Spearman correlations of the relative abundances for those genes represented by both an mRNA and a protein showed a weak (rs = 0.4; P < 0.001) relationship, indicating that post-transcriptional processes play a critical role in regulating the protein level during infection. Taken together, our study suggested that a joint analysis of the transcriptomic and proteomic of barley data can provide useful insights that may not be deciphered from individual analysis of mRNA or protein expressions.
Pseudomonas aeruginosa owns a variability of virulence factors. These factors can increase bacterial pathogenicity and infection severity. Despite the importance of knowledge about them, these factors are not more characterized at level of strains derived from local food products. This study aimed to characterize the virulence potential of P. aeruginosa isolated from various animal products. Several structural and virulence genes of P. aeruginosa including lasB, exoS, algD, plcH, pilB, exoU, and nan1 were detected by polymerase chain reaction (PCR) on 204 strains of P. aeruginosa. They were isolated from bovine meat (122), fresh fish (49), and smoked fish (33). The 16S rRNA gene was detected on 91.1% of the presumptive strains as Pseudomonas. The rpoB gene showed that 99.5% of the strains were P. aeruginosa. The lasB gene (89.2%) was the most frequently detected (p < 0.05). In decreasing importance order, exoS (86.8%), algD (72.1%), plcH (72.1%), pilB (40.2%), and exoU (2.5%) were detected. The lasB gene was detected in all strains of P. aeruginosa serogroups O11 and O16. The prevalence of algD, exoS, and exoU genes in these strains varied from 51.2% to 87.4%. The simultaneous determination of serogroups and virulence factors is of interest for the efficacy of surveillance of infections associated with P. aeruginosa.
Authors:Rita Bán, Gellért Baglyas, Ferenc Virányi, Balázs Barna, Katalin Posta, József Kiss and Katalin Körösi
White rot caused by Sclerotinia sclerotiorum (SS) is one of the most devastating plant diseases of sunflower. Controlling this pathogen by available tools hardly result in acceptable control. The aim of this study was to elucidate the effects of plant resistance inducers, BTH (benzothiadiazole in Bion 50 WG) and arbuscular mycorrhizal fungi (AMF) on disease development of white rot in three sunflower genotypes. Defence responses were characterized by measuring the disease severity and identifying cellular/histological reactions (e.g. autofluorescence) of host plants upon infection. Depending on the host genotype, a single application of inducers reduced disease symptoms. Histological examination of host responses revealed that BTH and/or AMF pre-treatments significantly impeded the development of pathogenic hyphae in Iregi szürke csíkos and P63LE13 sunflower plants and it was associated with intensive autofluorescence of cells. Both localized and systemic induction of resistance was observed. Importantly, the frequency of mycorrhization of hybrid P63LE13 and PR64H41 was significantly increased upon BTH treatment, so it had a positive effect on the formation of plant-mycorrhiza interactions in sunflower. To our knowledge, this is the first report on the additive effect of BTH on mycorrhization and the positive effect of these inducers against SS in sunflower.
Authors:C. N. Manju, V. K. Chandini and K. P. Rajesh
Cololejeunea manilalia sp. nov., an epiphyllous leafy liverwort, collected from the high altitude, tropical wet evergreen shola (cloud forest) of the New Amarambalam Reserved Forest in the Western Ghats of India is described and illustrated.
Authors:F. Gomez-Coronado, M.J. Poblaciones, A.S. Almeida and I. Cakmak
The combined application of nitrogen (N) and zinc (Zn) appears to be a promising agronomic strategy for the biofortification with Zn. To evaluate such efficiency, a field experiment was conducted in south-eastern Portugal under Zn-deficient soil. Four advanced breeding lines and two commercial varieties of bread wheat (Triticum aestivum L.) were fertilized with five treatments: i) control, ii) two foliar Zn applications, iii) one foliar Zn+N application, iv) soil and two foliar Zn applications, and v) soil and one foliar Zn+N application. Grain Zn content varied greatly across treatments and INIAV-1 and the commercial varieties were the most interesting cultivars in all the treatments. Grain Zn concentrations higher than the target level of 38 mg Zn kg−1 were obtained only when two foliar Zn applications were applied, alone or in combination with soil Zn applications, and grain Zn bioavailability also was more adequate (phytate:Zn ratios similar to 15). Soil Zn application resulted in grain yield increases between 7–10%, which virtually offset the extra application cost. The combined soil and two foliar treatment could be a good option for biofortifying bread wheat under Zn-deficient soils.
Authors:Carola Edler, Henri Derschum, Mirko Köhler, Heinrich Neubauer, Hagen Frickmann and Ralf Matthias Hagen
Reliable identification of pathogenic Burkholderia spp. like Burkholderia mallei and Burkholderia pseudomallei in clinical samples is desirable. Three different selective media were assessed for reliability and selectivity with various Burkholderia spp. and nontarget organisms.
Mast Burkholderia cepacia agar, Ashdown + gentamicin agar, and B. pseudomallei selective agar were compared. A panel of 116 reference strains and well-characterized clinical isolates, comprising 30 B. pseudomallei, 20 B. mallei, 18 other Burkholderia spp., and 48 nontarget organisms, was used for this assessment.
While all B. pseudomallei strains grew on all three tested selective agars, the other Burkholderia spp. showed a diverse growth pattern. Nontarget organisms, i.e., nonfermentative rod-shaped bacteria, other species, and yeasts, grew on all selective agars. Colony morphology did not allow unambiguous discrimination.
While the assessed selective media reliably allowed the growth of a wide range of B. pseudomallei strains, growth of other Burkholderia spp. is only partially ensured. Growth of various nontarget organisms has to be considered. Therefore, the assessed media can only be used in combination with other confirmative tests in the diagnostic procedure for the screening for melioidosis or glanders.
Authors:Eliane von Klitzing, Fulya Öz, Ira Ekmekciu, Ulrike Escher, Stefan Bereswill and Markus M. Heimesaat
Secondary abiotic mice generated by broad-spectrum antibiotic treatment provide a valuable tool for association studies with microbiota derived from different vertebrate hosts. We here generated human microbiota-associated (hma) mice by human fecal microbiota transplantation of secondary abiotic mice and performed a comprehensive survey of the intestinal microbiota dynamics in offspring of hma mice over 18 weeks following weaning as compared to their mothers applying both cultural and molecular methods. Mice were maintained under standard hygienic conditions with open cages, handled under aseptic conditions, and fed autoclaved chow and water. Within 1 week post weaning, fecal loads of commensal enterobacteria and enterococci had decreased, whereas obligate anaerobic bacteria such as Bacteroides/Prevotella species and clostridia were stably colonizing the intestines of hma offspring at high loads. Lactobacilli numbers were successively increasing until 18 weeks post weaning in both hma offspring and mothers, whereas by then, bifidobacteria were virtually undetectable in the former only. Interestingly, fecal lactobacilli and bifidobacteria were higher in mothers as compared to their offspring at 5 and 18 weeks post weaning. We conclude that the intestinal microbiota composition changes in offspring of hma mice, but also their mothers over time particularly affecting aerobic and microaerobic species.
This study was carried out in order to investigating the effect of travelling on the transmission of tuberculosis from high- to low-burden TB countries. Mycobacteria samples isolated from patients of distinct and relatively co-related countries (Azerbaijan Republic and Tabriz [located in the northwest of Iran]) were analyzed through 15 loci MIRU-VNTR typing method. PCR was done using special primers for each of the loci; then the number of allele repeats for all loci were determined by the size of their fragments. Finally, the created numeric patterns for each isolate were analyzed and clustered, using MIRU-VNTRplus.org website. All 119 isolates dispersing at 106 distinct patterns were composed of 10 clusters with 23 members and 96 unique patterns. Nine and five loci had high and moderate discriminatory power, respectively, but only one of them was poor in clustering. The study showed that 89.08% of TB cases involved resulted from the reactivation pattern and 10.92% were related to ongoing transmission. Although Azerbaijan Republic is a higher-burden TB region than Tabriz and Azerbaijan people make frequent tours to Tabriz to receive low or free medical services, the findings showed no TB transmission from the regions at least during the year of the study.
Authors:Balázs Gerics, Ferenc Szalay, Péter Sótonyi and Veronika Jancsik
Melanin-concentrating hormone (MCH), the neuropeptide produced mainly in the hypothalamus, plays an operative role in regulating food intake and the sleep/wake cycle. Considering that these physiological functions pursue diurnal variations, we checked whether the total hypothalamic MCH level depends on the time of the day. The aggregated MCH peptide content of the whole MCH neuron population was significantly higher at the end of the sleeping period (lights on), than at the end of the active period (lights off). This result, together with earlier observations, indicates that in contrast to the MCH gene expression, the level of MCH peptide is object of circadian variation in the hypothalamus.
Authors:Z.Y. Yang, C.Y. Liu, Y.Y. Du, L. Chen, Y.F. Chen and Y.G. Hu
Rht18, derived from Triticum durum (tetraploid) wheat, is classified as a gibberellic acid (GA)-responsive dwarfing gene. Prior to this study, the responses of Rht18 to exogenous GA on agronomic traits in hexaploid wheat were still unknown. The response of Rht18 to exogenous GA3 on coleoptile length, plant height, yield components and other agronomic traits were investigated using F4:5 and F5:6 hexaploid dwarf lines with Rht18 derived from two crosses between the tetraploid donor Icaro and tall Chinese winter wheat cultivars, Xifeng 20 and Jinmai 47. Applications of exogenous GA3 significantly increased coleoptile length in both lines and their tall parents. Plant height was significantly increased by 21.3 and 10.7% in the GA3-treated dwarf lines of Xifeng 20 and Jinmai 47, respectively. Compared to the untreated dwarf lines, the partitioning of dry matter to ears at anthesis was significantly decreased while the partitioning of dry matter to stems was significantly increased in the GA3-treated dwarf lines. There were no obvious changes in plant height and dry matter partitioning in the GA3-treated tall parents. Exogenous GA3 significantly decreased grain number spike–1 while it increased 1000-kernel weight in both the dwarf lines and tall parents. Thus, applications of exogenous GA3 restored plant height and other agronomic traits of Rht18 dwarf lines to the levels of the tall parents. This study indicated that Rht18 dwarf mutants are GA-deficient lines with impaired GA biosynthesis.