Showing papers in "Biologia in 2020"

Antimicrobial resistance in aquaculture: a crisis for concern

Abstract: Emergence of antimicrobial resistance (AMR) in cultured fishes is one of the major challenges faced in aquaculture. The high prevalence of bacterial infections in fishes leads to frequent use of antibiotics and thus their persistence in the aquatic environment, which in turn results in the proliferation of antibiotic resistant bacteria. The AMR in aquaculture can be transferred to clinically important strains of natural environment through horizontal gene transfer, thereby affecting the whole ecosystem. Most of the cultured fishes, including ornamental possess diverse pathogens exhibiting multiple antibiotic resistance. A thorough understanding of the gene transfer systems such as plasmids, transposons, integrons and gene cassettes can unravel the complexity of antimicrobial resistance in aquaculture. Continuous monitoring programmes, timely detections of the resistant bacteria and implementation of proper regulations are necessary to curb the dissemination of AMR in aquaculture. The present review summarises the antimicrobial use and AMR in cultured fishes, genetic mechanisms involved in the development of resistance, and the management strategies to restrict the spread of AMR in aquaculture.

Microbial Laccase: a robust enzyme and its industrial applications

Abstract: Laccases (E.C. 1.10.3.2) are most stable and powerful biocatalysts with broad applications. It is a copper containing, organic solvents resistance, oxidoreductase enzyme, having potential ability to oxidize the phenolic and non-phenolic compounds to produce dimers, oligomers, and polymers. Laccase are widely distributed in nature ranging from prokaryotes to lower eukaryotes and fungi to plants. In their natural surroundings, Laccases are responsible for the biological degradation of lignin and received much attention among researchers in last decade, due to their wide-spread applicability and stability. The huge versatility of laccase due to their broad range of substrate specificity makes laccase highly suitable for various fields of industrial applications such as paper and pulp industry, textile applications, bioremediation, food processing, pharmaceutical and nanobiotechnological applications, bio-bleaching of synthetic dyes and biodegradation of xenobiotic compounds. Laccase mediated enzymatic treatment has been considered as, an effective process towards their adequate effect of real industrial decolourization of dye-contaminated wastewater, improving and texturing the food quality in affordable cost, less-time consuming at state-of-environmental risk. A present review is a brief analysis about this prominent group of enzymes and increase knowledge about its applications further which would encourage the use of laccase based production for economical purposes in future.

miRNA applications for engineering abiotic stress tolerance in plants

Abstract: MicroRNAs (miRNAs) are endogenous, tiny RNA molecules that sit at the heart of regulating gene expression in numerous developmental and signaling pathways. Recent investigations have revealed that abiotic stresses encourage non-typical expression patterns of several miRNAs, accordingly proposing miRNAs as potent and novel targets for enhancement plant tolerance against abiotic factors. The stress driven miRNA-response is dependent on types of miRNA, stress, tissues or organs as well as plant genotype. The stress responsive miRNAs act either as negative-regulatory entities by down regulating negative regulators for stress tolerance or as positive-regulatory entities approving amassing of positive regulators. The current scenario on miRNA-based research vastly focus on the identification and target prediction/validation of stress-responsive miRNAs along with their functional expression under stress conditions. It has predominately been accomplished with the advent of high throughput sequencing technologies coupled with online databases and tools. However, there is an urge of epigenomics, functional characterization, and expression-pattern studies to illuminate the communal regulatory pathways by miRNAs that trigger abiotic stress tolerance in major crops. The short tandem target mimic (STTM) and genome editing technologies can be exploited for efficient utilization of miRNAs for traits improvement. Beside the classical pathways, non canonical pathways and novel loci of miRNAs origin and their possible role in abiotic stress response need to be deciphered for their effective utilization. Through this review, we are presenting herein a current understanding about plant miRNAs, their biogenesis and involvement in stress-responses and modulation, various tools and databases used for prediction/identification of plant miRNAs and their targets. A perspective analysis on use of miRNAs as potent targets to engineer abiotic stress tolerance in plants has been presented with emphasis on recent developments, challenges and future perspectives.

Effectiveness of edible coating based on chitosan and Natamycin on biological, physico-chemical and organoleptic attributes of Iranian ultra-filtrated cheese

Abstract: Edible coatings can be applied on the surface of fruits and food pieces to improve their nutritional and sensory qualities. Present study focuses on the effects of applied edible coating formulation containing 1.6% W/V chitosan and 18.5 ppm Natamycin, on the surface of Iranian Ultra-filtrated (UF) cheese and evaluates biological, physico-chemical and organoleptic attributes of the coated cheeses as compared to those of the control samples, during 6 weeks of storage at temperature of 4 ± 2 °C. Coated and control samples were analyzed for bacterial total count, molds and yeasts population, coliform count and starter populations, as biological characteristics. pH, acidity, firmness, and salt, moisture, dry mater, fat and fat in dry mater contents were evaluated for both samples, as their physico-chemical properties. Appearance, odor and flavor, taste, texture and overall acceptability were evaluated for both coated and control cheese samples at weeks 3 and 6 of storage, as their sensorial attributes. Sensorial analysis indicated that, however there were insignificant differences between the values of sensory parameters for both samples at week 6, but, provided coating could significantly maintained sensory attributes of the coated cheese as compared to those of the control samples, at week 6 of storage.

Foliar spray of salicylic acid induces physiological and biochemical changes in purslane (Portulaca oleracea L.) under drought stress

Abstract: Purslane (Portulaca oleracea L.) is a plant with a long history in cooking and folk medicine that has been distributed worldwide. In the present study, purslane was used as a model plant to investigate the effect of foliar application of salicylic acid (SA) on plant tolerance to drought stress. The effects of SA foliar spray (0, 0.5 and 1 mM) on physiological and biochemical responses of purslane seedlings under drought stress (90, 60 and 30% field capacity) were investigated. The results showed that drought stress decreased the contents of photosynthetic pigments, parameters of gas exchanges, proline, soluble sugars, total phenolic, flavonoids, growth, and biomass production. However, SA improved photosynthetic pigments, gas exchanges, compatible solutes and secondary metabolites and thereby increased purslane growth and biomass production. Drought stress also induced oxidative stress (H2O2 and MDA) in purslane seedlings; however, SA reduced the drought-induced oxidative stress by regulating the activity of antioxidant enzymes. Drought stress increased the content of palmitic and arachidonic acid and decreased unsaturated fatty acids (oleic, linoleic and linolenic acid), stearic and behenic acid in the leaves of purslane. However, SA improved the fatty acids content under drought stress. These results indicate that foliar application of SA improved the adaptation and tolerance of the purslane plant to drought stress by improving gas exchange, increasing the accumulation of secondary metabolites and compatible solutes, improving the antioxidant defence system and regulating the fatty acids profile of membrane lipid.

Faunal biodiversity research in the Republic of Georgia: a short review of trends, gaps, and needs in the Caucasus biodiversity hotspot

Abstract: We evaluated progress towards animal biodiversity research in Georgia, a key area in the Caucasus biodiversity hotspot. By reviewing recently (1990–2018) published articles in all areas of animal diversity research, we unmasked the trends in biodiversity inventory, ecological and biogeographical studies, and conservation issues in Georgia. We concluded that species inventory and biodiversity research in Georgia has significantly increased during the last ten years, however the rate and extent of investigation is far from satisfactory. Major gaps remain in all branches of animal diversity research in Georgia, and consequently existing knowledge is inadequate to address modern challenges related to species and ecosystem conservation. We urge local governmental authorities and international scientific societies to support development of stronger research facilities and cultivate interest in biodiversity inventory and research in Georgia as an important step towards maintaining globally important biodiversity in the Caucasus.

Roach nectarivory, gymnosperm and earliest flower pollination evidence from Cretaceous ambers

Abstract: Direct fossil evidence for Mesozoic flower pollination is scarce. Umenocoleoid micro-cockroaches Lepidopterix vegrandis gen. et sp. n. (Lebanese amber) and Antophiloblatta hispida gen. et sp. n. (Myanmar amber) possess size, form, complex coloration pattern and surface structure, cryptic with potentially entomophilous angiosperms Tropidogyne pentaptera Poinar, 2017 and Antiquifloris latifibris Poinar et Buckley, 2016 flower petals and sepals. Putative pollen grains attached to the latter adult indicates pollination, while reduced mouthparts suggest fluid nectar feeding. Spongistoma angusta gen. et sp. n. (Myanmar amber) has a narrow body and mandibles nearly entirely reduced with a unique “proboscis” forming sponging/ sucking mouthparts. In addition putative Classopolis Pflug, 1953 gymnosperm pollen is attached to adults and immature individuals of Vzrkadlenie miso gen. et sp. n. (Myanmar amber). Together with possible angiosperm pollination by Formicamendax vrsanskyi Hinkelman, 2019 and cycas pollination by immature individuals of alienopterid larvae, the evidence for early cockroach pollination is now substantial. Additionally unique is the forewing surface of L. vegrandis with photonic crystal structures within the scales.

Chlorogenic acid supplementation improves skeletal muscle mitochondrial function in a rat model of resistance training

Abstract: Chlorogenic acid (CA), is a polyphenol abundantly found in several foods. Different pharmacological roles of CA, including its effect on body weight, become a subject of research interest. In the current study, the effect of CA supplementation was evaluated on the muscle mitochondria function in an animal model of resistance training (RT). Rats were allotted into control, CA (100 mg/kg) without RT, RT, RT + CA 10 mg/kg, RT + CA 50 mg/kg, and RT + CA 100 mg/kg. It was found that CA supplementation (10, 50, and 100 mg/kg, gavage, 56 consecutive days) significantly improved muscle strength and mitochondrial function, especially when it was co-administered with the RT program. The present findings suggest that CA supplementation with RT improved muscle function by regulating mitochondrial function and cellular energy metabolism. Therefore, CA could be a promising, supplementary/therapeutic agent against a variety of skeletal muscle-associated complications.

Comparative analyses of chloroplast genomes of Theobroma cacao and Theobroma grandiflorum

Abstract: Theobroma is a plant genus included in tribe Theobromeae, subfamily Byttnerioideae Burnett and family Malvaceae. Discrepancies exist in taxonomy at family and genus level. Here, we compared structures of two previously reported chloroplast genomes of Theobroma cacao and Theobroma grandiflorum after correction of annotation and search for highly polymorphic regions which could be used to design molecular markers to investigate phylogenetic relationships among the genus. Both chloroplast genomes showed similar structure, gene content and organization. The correctly annotated genomes contained 130 genes including 8 ribosomal RNA, 37 tRNA genes and 85 protein-coding genes. The amino acids frequencies, codon usage, putative RNA editing sites, microsatellites and oligonucleotide repeats were alike in two genomes. Polymorphic hotspot regions were mostly observed in intergenic regions followed by intronic regions, as well as in coding sequences of few genes. We identified 30 polymorphic loci including trnH-psbA, ndhE-ndhG, rpl32-trnL, trnP-PsaJ, rpl33-rps18, trnQ-psbK, trnS-trnG, and ndhF-rpl32 that might be suitable for development of appropriate and suitable markers for inferring of genus Theobroma phylogeny. The inferring of phylogeny with the markers of these loci might be helpful to identify genetically compatible and closely related species to T. cacao and T. grandiflorum for breeding purposes to produce quality cultivars of these species for high quantity of fruit production and with high resistance towards the pathogens.

Soil macroarthropod community and soil biological quality index in a green manure farming system of the Brazilian semi-arid

Abstract: Soil macroarthropods are organisms considered as key factors to sustain soil quality and sustainability due to their services to soil ecosystem. The community structure and seasonal variation of soil macroarthropods in 5-year cultivation of green manure plant species in the Brazilian semi-arid, Areia, Paraiba, Brazil were investigated between June and December 2018. Soil samples and macroarthropod specimens were collected using soil cores and Provid-type traps, respectively, during rainy and dry seasons. We characterized both soil chemical properties and macroarthropod community under ten green manure plant species: Brachiaria decumbens Stapf. cv. Basilisk, Canavalia ensiformis (L.) DC, Crotalaria juncea L., Crotalaria ochroleuca G. Don, Crotalaria spectabilis Roth, Lablab purpureus (L.) Sweet, Mucuna pruriens (L.) DC., Neonotonia wightii (Wight & Arn.) J.A. Lackey, Pennisetum glaucum L., and Stilozobium aterrimum Piper & Tracy. The highest values of richness, diversity and dominance in the macroarthropod community during the rainy season were found on the plots where C. spectabilis and M. pruriens were cultivated, whereas during the dry season the highest values were found in the plots where C. ochroleuca, C. spectabilis, and S. aterrimum were cultivated. In the plots where B. decumbens and P. glaucum where cultivated, we found lower values of richness, diversity, and dominance in the macroarthropod community compared to the leguminous plant species during rainy and dry seasons. Our findings suggest that: 1) green manure practice and seasonality changed soil macroarthropod community, trophic structure, and ecological processes in semi-arid conditions; and 2) abundance of predators, ecosystem engineers, decomposers and herbivores was promoted by plant species from Fabaceae family. The results highlight the importance to consider plant species from Fabaceae family as habitat and food resources for soil fauna community.

Salinity stress alters ion homeostasis, antioxidant activities and the production of rosmarinic acid, luteolin and apigenin in Dracocephalum kotschyi Boiss

Abstract: Salt stress affects growth and secondary metabolism in medicinal plants. There is no information about the impacts of salt stress on Dracocephalum kotschyi Boiss. Therefore, in this study, the 60-day old seedlings grown in coco peat and perlite were irrigated with various concentrations of NaCl (0, 25, 50, 75, and 100 mM) in accordance with a randomized complete block design for 3 weeks. The results showed that with increasing salt concentration, Na+ concentration was increased, but Ca2+ and K+ concentrations and fresh and dry weights were decreased in both roots and shoots. Besides, photosynthetic pigments and relative water content declined, whereas proline concentration and electrolyte leakage levels elevated in leaves under salinity stress. The activities of ascorbate peroxidase and guaiacol peroxidase enzymes were enhanced at lower salt concentrations but impaired under higher concentrations of NaCl. High-performance liquid chromatography showed that the contents of rosmarinic acid, luteolin, and apigenin were increased with aggravation of salt stress. The highest total phenolic and flavonoid contents and the rosmarinic acid, luteolin, and apigenin contents were verified at 75 mM NaCl that was concomitant with the most 2,2-diphenylpicrylhydrazyl scavenging activity in the leaves. In contrast, all these attributes decreased under 100 mM NaCl. In conclusion, the results unveiled that D. kotschyi is a moderate salt-tolerant plant and adaptive mechanisms adopted by this plant are including Na+ exclusion in roots, the activation of the antioxidant system, and the alteration of phenolic profile. This study also suggests that mild to moderate salinity can be employed as an elicitor to increasing some pharmaceutical important phenolic compounds in D. kotschyi.

Checklist and red list of mosses (Bryophyta) of Slovakia

Abstract: An updated checklist and Red List of the mosses of Slovakia is presented. The checklist consists of 699 species with two additional subspecies and 21 additional varieties. According to the Red List presented here, 31.0% of the moss flora of Slovakia was evaluated as threatened (categories Critically Endangered, Endangered, Vulnerable), 9.2% as near threatened, 7.3% as data deficient taxa and 49.4% of mosses were classified in the Least Concern category. We modified the category Extinct (EX) to Regionally Extinct/Vanished (RE/VA), which now includes 2.9% of the moss flora. Species Grimmia lisae, Hygrohypnum eugyrium, Lewinskya affinis var. bohemica, Niphotrichum elongatum, Oreas martiana, Orthotrichum moravicum, Osculatia bornholmensis, Tortula cernua and T. randii have been reported recently as new for Slovakia.

The induction of salt stress tolerance by jasmonic acid treatment in roselle (Hibiscus sabdariffa L.) seedlings through enhancing antioxidant enzymes activity and metabolic changes

Abstract: The objective of the present study was to assess the effects of exogenous application of 1 mM Jasmonic acid (JA), an endogenous plant growth regulator, on mitigation of oxidative and osmotic stresses caused by various levels of NaCl: none (0 mM), light (50 mM), moderate (150 mM), and severe (300 mM) in roselle (Hibiscus sabdariffa L.) seedlings. Salt stress without any change in leaf water content negatively affected seedlings growth from the aspect of plant height, root length, leaf morphological properties, plant biomass and levels of pigments, reducing sugars, starch, proteins and free amino acids, but accumulated higher levels of non-reducing sugars, total phenols, anthocyanins, flavonoids, proline and increased activities of both enzymatic and non-enzymatic antioxidants, such as ascorbate peroxidase (APX), pyrogallol peroxidase (PPX) and polyphenol oxidase (PPO). JA-treated seedlings exhibited a significant increase in growth parameters and activities of APX and PPX under salt stress, with hyper-accumulation of metabolite levels, but accumulated lower amounts of dry matter in roots and decreased the activity of PPO. These results clearly showed that exogenous JA treatment protected roselle seedlings against salt-induced damage through up-regulating the activity of H2O2-decomposing enzymes, osmoprotectants biosynthesis, and the accumulation of metabolites.

Drought tolerant bacterial endophytes with potential plant probiotic effects from Ananas comosus

Abstract: Endophytic bacteria with multi-trait plant probiotic features have been demonstrated to have applications to enhance agricultural productivity by supporting the plant growth, yield and disease resistance under harsh environmental conditions. The xerophytic plant Ananas comosus was selected as the source for endophytic bacterial isolation in the current study. This has resulted in the identification of organisms with antifungal and plant growth promoting properties. Interestingly, endophytic bacteria with antifungal activity were found to have drought tolerance property also. These organisms were demonstrated to express the plant beneficial mechanisms like IAA, ACC deaminase and nitrogen fixation under drought condition. The selected organisms were further identified as Bacillus sp. (Acb9), Providencia sp. (Acb11), Staphylococcus sp. (Acb12), Staphylococcus sp. (Acb13) and Staphylococcus sp. (Acb14)(Acb 14). In addition, LC-MS/MS analysis of extract from Acb 9 has resulted in the identification of surfactin with m/z of 994. Priming of selected endophytes with Vigna radiata seedlings also showed enhanced growth parameters such as shoot length, root length and root numbers when compared to the control. The shoot length of Acb 9 treatment was found to be 18.833 ± 0.687 cm, where the control value for same was 13.976 ± 0.585 cm and the root length was 3.9 ± 0.99 when compared to control (1.54 ± 0.628). The root length was 3.9±0.99 which was also higher than control (1.54±0.62).The results of the study indicate the promise of endophytic bacteria for field application under changing agro-climatic conditions.

Enhancement of salt tolerance in maize (Zea mays L.) using locally isolated Bacillus sp. SR-2-1/1

Abstract: The current study was aimed at enhancement of salt tolerance of maize by using a halotolerant plant growth promoting rhizobacterium. Maize seeds (FH-1137) were grown under salt stress with and without inoculation of a locally isolated Bacillus sp. SR-2-1/1. Inoculation of Bacillus sp. SR-2-1/1 significantly augmented the salt tolerance of maize plants which was reflected by increased contents of chlorophyll, total phenolics and proline. Moreover, inoculation of strain SR-2-1/1 resulted in less oxidative damage in terms of H2O2 production and lipid peroxidation. This was further supported by higher catalase and peroxidase production in these plants. Bacillus sp. SR-2-1/1 exhibited positive effects on the expression of photosynthesis (RBCL), antioxidants status (CAT1, APX1, APX2) and plant ion homeostasis (NHX1, SOS1, H+-PPase, and HKT1) related genes. To the best of our knowledge, this is the first study reporting enhancement of salt tolerance in maize genotype FH-1137 by using plant growth promoting rhizobacterium. The use of Bacillus sp. SR-2-1/1 as bio-inoculant seems to be a sustainable alternative to alleviate salt-induced damages in maize. This approach can be applied to other plant species to increase salt tolerance.

Earliest behavioral mimicry and possible food begging in a Mesozoic alienopterid pollinator

Abstract: Morphological insect-insect mimicry is known from few Cretaceous cockroaches and a beetle. Formicamendax vrsanskyi gen. et sp. n. (Blattaria, Alienopteridae) shows myrmecomorph features such as an elongated, smooth and black body, simple fenestrated hindwing, legs lacking protective spines. Elbowed or “geniculate “antenna is a typical character of advanced ants and weevils used for different forms of communication. Together with reduced mouthparts and specialized palps still preserved grasping food, they evidence specialized behavioral mimicry. The attached symmetric angiosperm pollen on hindleg can provide rare evidence of insect-flower relations.

Efficient and rapid in-vitro plantlet regeneration via somatic embryogenesis in ornamental bananas (Musa spp.)

Abstract: A simple and efficient protocol developed for plantlet regeneration through in vitro somatic embryogenesis in three ornamental bananas. In vitro propagation, especially somatic embryogenesis has been a method of choice to obtain homogenous planting material in ornamental bananas. In the present investigation, true-to-type plants via somatic embryogenesis were achieved in three ornamental bananas viz. Musa laterita, Musa beccarii and Musa velutina using immature male flower bud as explants. The evaluation was carried out at two stages of somatic embryogenesis, induction, and maturation of somatic embryos. Embryogenic calli desiccated up to 2 h at 25 ± 1 °C resulted in higher frequencies of embryo induction and maturation compared to non-desiccated embryos. The plantlets generated were hardened, and the genetic fidelity of the plantlets was confirmed using SRAP markers. It was observed that banana plants derived via somatic embryogenesis displayed normal phenotype as that of plants grown from a single elite mother plant. In the present study, the successful establishment of plants from male flower bud was achieved in 6 to 7 months which is a relatively short duration compared to other reports involving different species of banana. The protocol developed could be useful for large-scale micropropagation studies in these commercially important ornamental bananas.

Zinc oxide nanoparticles induce necroptosis and inhibit autophagy in MCF-7 human breast cancer cells

Abstract: Several studies have shown the toxic effect of zinc oxide nanoparticles (NZnO) on various cancer cells. This study aimed to assess the cellular death mechanism of the NZnO in MCF-7 human breast cancer cells. The cells were pretreated with zVAD (apoptosis inhibitor), 3-MA (an autophagy inhibitor), and Nec (a necroptosis inhibitor) for two hours, followed by their exposure to NZnO for 48 h. In the presence of Nec and 3-MA, NZnO significantly reduced proliferation and viability of MCF-7 cells while the apoptotic index and Bax/Bcl-2 ratio was significantly increased, compared to the only NZnO-treated cells. In the only NZnO-treated cells expression of Caspases-3 and Caspase-8 were up-regulated. NZnO with Nec and 3-MA could significantly increase expression of Caspase-3 and Caspase-9, but not Caspase-8 in the MCF-7 cells. NZnO in presence of zVAD and 3-MA significantly increased expression of RIPK1, RIPK3, and MLKL genes, compared to the only NZnO-treated cells. Furthermore, viability and proliferation of MCF-7 cells in NZnO with the apoptosis and autophagy inhbitors were lower than the other experimental groups. NZnO with apoptosis and necroptosis inhibitors could significantly increase cell viability, cell proliferation, and relative expression of autophagy-related genes such as LC3-II, Beclin-1, and ATG5, compared to the only NZnO-treated. According to the results of this study, the high toxicity of NZnO toward breast cancer cells mainly depends on activation of necroptosis and suppression of autophagy processes.

Thermophilous oak forests of the steppe and forest-steppe zones of Ukraine and Western Russia

Abstract: We present a formal classification of thermophilous oak forests of the steppe and forest-steppe zones of Ukraine and Russia. Using 45 sources (synoptic tables; some from Central and Western Europe were also included for comparative purposes), we classified the data using cluster analyses, followed by post-classification tools aimed at formal identification of the optimal number of clusters and fidelity-based table sorting. Db-RDA ordination and a CART were used to identify the lead putative climatic drivers of the vegetation patterns. Of the six clusters identified by our classification procedures, two clusters are interpreted here as new alliances (Betonico-Quercion, Scutellario-Quercion). Some new associations classified into these alliances were also either validated or described as new. We further show that the Quercion petraeae is of heterogenous nature and the position of the units previously classified as the Potentillo albae-Quercion should be re-evaluated. NMDS was used to analyse the patterns of the phytocoenologic elements (diagnostic species of relevant syntaxonomic classes) in the six clusters. This analysis revealed that the classification of the Ukrainian and Russian thermophilous oak forests into the Quercetea pubescentis class is untenable and remains open to further scrutiny.

Assessing biological water quality of Yalakdere stream (Yalova, Turkey) with benthic macroinvertebrate-based metrics

Abstract: This study was carried out in Yalakdere, which is the most important stream in Yalova, Turkey, in order to determine biological water quality, by using macroinvertebrate-based metrics and a multimetric index that was developed. In addition, it was also aimed to investigate the effects of drought and highway construction on stream benthic macroinvertebrates during the study period. Samples of benthic macroinvertebrates and eighteen physicochemical variables were collected for one year period from four study sites monthly. A total of forty metrics in five main metric groups calculated based on benthic macroinvertebrates were evaluated. It was determined that fourteen benthic metrics were significantly correlated with physicochemical variables. Since the same type of metrics give similar results, only one candidate metric from each of the five metric groups was added to evaluate the multimetric index. During the drought observed throughout 2013–2014 in Turkey, the stream bed was dry in the summer months. According to the multimetric index results, the water quality of the first three sampling points before the drought ranged between Class I and Class III while the water quality after the drought (after October 2013) did not go above Class III. No significant difference was observed in the number of taxa detected in the stream after the drought. However, it was found that the number of organisms per square meter decreased seven times after the drought. It is concluded that the developed multimetric index is an effective tool to determine the stream conditions, antropogenic pressures such us highway constructions and the negative effects of summer droughts.

Groundwater use of a small Eucalyptus patch during the dry monsoon phase

Abstract: Given the critical role of water in rural development, it is essential to quantify water use by various sectors. Reportedly, a significant water loss during the dry monsoon phase is by Eucalyptus trees in the Ethiopian highlands but few quantitative studies have been carried out. In our study in the Fogera plain near Lake Tana, consumptive water use of a small Eucalyptus patch was calculated from the fluctuating diurnal water table observations for two dry monsoon phases. During the dry monsoon phase in 2014, the groundwater table declined linearly at a rate of 2.6 cm d−1 and in 2015 the decline was 2.5 cm d−1. Daily fluctuations in groundwater were around 20 cm. Translating changing groundwater levels in precise evapotranspiration rates was cumbersome because of uncertainty in the value of drainable porosity. We concluded that the evapotranspiration over the small Eucalyptus patch was at a minimum 3.4 mm d−1 but more likely around 10 mm d−1 at the end of the dry phase. The 10 mm d−1 is twice the reference evaporation rate. This is in accordance with advection aridity approach where the actual evaporation of isolated patches with access to groundwater in dry environments can evaporate at twice the reference rate. The current and future extent of Eucalyptus patches and forests need, therefore, be considered in the management of the groundwater resource.

Identification of suitable reference genes for normalization of RT-qPCR data in eggplant fruit and shoot borer (Leucinodes orbonalis Guenée)

Abstract: The eggplant shoot and fruit borer, Leucinodes orbonalis Guenee (Lepidoptera: Crambidae) is a monophagous and destructive insect pest of eggplant. L. orbonalis developed multiple insecticide resistance that led to frequent field control failures in many countries. The possible reversal of resistance in L. orbonalis requires an understanding of the expression dynamics of individual genes conferring resistance to insecticides through gene expression analysis. The availability of reference genes (RG) to normalize transcript data of target genes, achieved by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR), is mandatory. Hence, the present study investigated the stable expression pattern of nine putative reference genes viz., actin, 28S ribosomal protein S18c, mitochondrial isoform X2 (28SM), calnexin, β-tubulin, 28S ribosomal protein S3 mitochondrial (28SR3), TATA box binding protein (TATA), elongation factor-1α (EF-1α), glyceraldehyde-3-phosphate-dehydrogenase (GAPDH), and ubiquitin 60S ribosomal protein (Ubiquitin) to select the most stable genes that could be used as reference genes for target transcript gene normalization. Different algorithms such as ΔCt, geNorm, NormFinder and BestKeeper were used to assess gene expression stability. By integrating these data into online RefFinder tool, 28SR3 and GAPDH, were chosen as highly suitable RGs based on their stable expression pattern.

Role of brassinosteroids in mitigating abiotic stresses in plants

Abstract: Plants require extrinsic factors like air, water, light, nutrition, etc. for the regulation of their growth and development. Similarly, phytohormones are equally important for plants as intrinsic factors. Phytohormones are active molecules vital for various aspects in growth and development starting from embryogenesis, plant-pathogen defense and organ size regulation to reproductive development. These hormones also play an active role in mediating defense response against biotic and abiotic stresses in plants. According to estimates, a substantial loss in agricultural yields leading to concerns on food security worldwide has been reported due to abiotic stresses like salinity, extreme temperatures, drought, etc. To cope up with harsh stress conditions, plants develop certain altered growth patterns and physiological processes. Among various groups of phytohormones produced by plants, those which are based on isoprenoid origin are quite important in safeguarding plants against environmental stress. Brassinosteroids are one of the novel groups of plant hormones of isoprenoid origin. Due to its remarkable growth supporting property, these are regarded as phytohormones with pleiotropic effects. They dominate miscellaneous physiological activities such as growth, development, rhizogenesis, seed germination, senescence and most importantly abiotic stress tolerance in plants. In general, when a plant perceives a signal produced by stress, then it triggers a cascade mechanism of signal transduction with plant growth regulators, acting as alphatransducers.

Habitat suitability mapping of stone pine (Pinus pinea L.) under the effects of climate change

Abstract: Climate models predict that the Mediterranean region will experience a particularly marked increase in aridity during the 21st century when compared to other regions. This study examines the current and future potential geographical distribution of the stone pine (Pinus pinea L.), a species of considerable ecological and economic importance, in the light of aridity predictions in the Mediterranean region. For this purpose, 19 bioclimatic variables taken from the Worldclim database in 30 arc-second spatial resolution (∼1000 m) were used. The bioclimatic variables that displayed high correlations with one another when applied to 125 pieces of presence data pertaining to the species were reduced using Principal Component Analysis (PCA) and the current and future potential distribution areas of the species were identified using MaxEnt 3.4.1 software. To determine the future geographical distribution of the species under the impact of climate change, the Community Climate System Model (CCSM ver. 4) was used to model the potential geographical distribution areas for two climate scenarios – Representative Concentration Pathways (RCP) 4.5 and 8.5 – and two time periods (2041–2060 and 2061–2080). According to the model data, the predicted potential geographical distribution areas of the stone pine increase under the 2041–2060 and 2061–2080 RCP 4.5–8.5 scenarios and move northwards and towards higher altitudes. Knowledge of the current and future potential distribution maps of the species, and especially of the suitable/very suitable distribution areas, can be used in work on land use, afforestation, ecological restoration and the protection of the species.

The eradication of Carpobrotus spp. in the sand-dune ecosystem at Sterpaia (Italy, Tuscany): indications from a successful experience

Abstract: Carpobrotus spp. is a well-known invasive plant native to South Africa whose detrimental effects on local communities are widely documented. We report the experience from the eradication of this species from the Coastal Park of Sterpaia, a Natural Protected Area of Local Interest in Tuscan coast (Italy), an action comprised in a restoration project carried out from 2012 to 2015. In the area of study, Carpobrotus spp. occurred on about 8000 m2 mostly with a cover close to 100 %. The eradication was carried out mainly by the use of chemical control (glyphosate), with the integration of manual removal in areas with a low Carpobrotus spp. stand cover. To evaluate the recovery of native species vegetation we sampled the total cover of Carpobrotus spp. and of the other native plants before the treatments and for 3 years after them. The control with glyphosate resulted an efficient method, leading to a significant decrease of Carpobrotus spp. cover and to a rapid recovery in native species cover and richness and diversity. The composition of the sampled plots displayed critical changes already 1 year after the control actions on the invasive species. In conclusion, our results report the important consequences of the eradication of this invasive species, particularly showing the good results achieved by means of chemical control methods, resulting in a rapid recover of native species.

Cystoseira barbata marine algae have a molluscicidal activity against Biomphalaria alexandrina snails supported by scanning electron microscopy, hematological and histopathological alterations, and larvicidal activity against the infective stages of Schistosoma mansoni

Abstract: Schistosomiasis is one of the neglected tropical diseases. Biomphalaria spp. is the intermediate host of Schistosoma mansoni. The aim of this study is to evaluate the molluscicidal activity of the ethanolic extract of Cystoseira barbata marine algae on Biomphalaria alexandrina snails. The present results indicated that HPLC of C. barbata ethanolic extract contained 20 flavonoids, 20 phenolic compounds and 10 saccharides. It has a molluscicidal activity on B. alexandrina snails at LC50 175.04 mg L− 1 after 48 h of exposure. Scanning electron microscope of the head foot region of B. alexandrina snails exposed to 2 LC50 (175.04 mg L− 1) of the ethanolic extract shows the rough surface and damaged cilia in the tentacles and the foot region; the mantle contained erosion in its tegmental surface. Exposure to LC50 of the ethanolic extract caused ovicidal, miracidicidal and cercaricidal effects. Examinations of the hemocytes monolayers of the exposed snails showed that hyalinocytes had a shrunken nucleus and granulocytes had irregular cell membrane, forming pseudopodia. Histopathological changes occurred in the head foot region after exposure to LC50 of the extracted algae, where, vacuoles, shrinkage in the mucous secreting glands and splitting of the oblique muscle fibers were present. Also, histopathological alterations occurred in the digestive gland where the digestive cells were ruptured, vacuolated and there was a marked increase in the number of the secretory cells and these alterations were concentration dependent. Conclusively, C. barbata ethanolic extract contains bioactive molecules that could be developed as molluscicides for the control of freshwater intermediate hosts for schistosomiasis.

Evaporation from soils of different texture covered by layers of water repellent and wettable soils

Abstract: Water repellent soils are able to channel water deep into the soil profile by fingered flow, minimising water storage in the water repellent top layer where water is most susceptible to evaporation. To date, the effect of water repellent or wettable surface layer on evaporation from wet sublayer has only been reported for coarse materials, and an increase in water repellency led to a greater delay in water evaporation. The objective of this study was to assess the effect of water repellent vs. wettable top layers with different thickness on water evaporation from coarse and fine texture subsoils that were pre-moistened. Clay loam soil samples were taken from Pinus pinaster woodland of Ciavolo, Italy, and sandy soil samples from Pinus sylvestris woodland of Sekule, Slovakia. Evaporation from soil samples was determined from the loss of weight in laboratory conditions. Water in the clay loam soil from Ciavolo was held for a longer period due to slower evaporative loss than in the sandy soil from Sekule, and the impact of the water repellent layer on the loss rate over time is related to its thickness. Over 550 h, about 90% of the initial stored water was evaporated from the uncovered clay-loam soil sample from Ciavolo. In the same time, the 0.3, 1, and 2 cm-thick duff layers, respectively, saved about 23, 34, and 58% of water from evaporation, and evaporation of 90% of water took over 780, 1100, and 1450 h. It means that the clay loam soil cover with the 0.3, 1, and 2 cm-thick duff layers resulted in prolonging the evaporation by 10, 23, and 37.5 days, respectively. As to the sandy soil from Sekule, 98% of water was evaporated from the uncovered soil sample over 240 h. In the same time, the 0.3, 1, and 2 cm-thick water repellent soil layers, respectively, saved about 7, 45, and 59% of water from evaporation, and evaporation of 98% of water took over 330, 606, and 774 h. It means that the sandy soil cover with the 0.3, 1, and 2 cm-thick water repellent soil layers resulted in prolonging the evaporation by about 4, 15, and 22 days, respectively. It can be concluded that water repellent surface layers, created by pine trees, are able to delay evaporation significantly for both coarse and fine textured soils, which may be particularly beneficial for plants during hot and dry periods in summer.

Ecological analysis of gamasid mites on the body surface of Norway rats (Rattus norvegicus) in Yunnan Province, Southwest China

Abstract: The Norway rat, Ratttus norvegicus, is a common agricultural pest and an important reservoir host of many zoonoses. A long-term field investigation on gamasid mites was made in 39 counties of Yunnan province, southwest China from 1990 to 2015. A total of 1448 Norway rats were captured, and 10,034 individuals of gamasid mites were collected from the body surface of the rats, which were identified as 42 species and 16 genera under 6 families. Based on some strategies of “data mining”, the present paper took advantage of the long-term accumulated original data and made an ecological analysis of gamasid mites on the Norway rat. The results showed that the infestation of gamasid mites on 1448 Norway rats was common with an overall prevalence (48.55%), mean abundance (6.93) and mean intensity (14.27). Of 42 species of gamasid mites, Laelaps nuttalli, Laelaps echidninus and Ornithonyssus bacoti were three dominant species, and they showed an aggregated distribution among different individuals of their rat host, R. norvegicus. There were much more species (39 species) of gamasid mites on the outdoor rats with a higher prevalence (65.12%), mean abundance (10.24) and mean intensity (15.72) than on the indoor rats (p < 0.001). The Norway rats in the lower altitude gradients showed a higher infestation prevalence and intensity of the mites, but lower species diversity. The adult rats had higher infestations (prevalence, mean abundance and mean intensity) of the mites than the juvenile rats. Most gamasid mites showed a predominantly male-biased sex ratio on Norway rats. The association coefficient was used to analyze the interspecific relationship between any two dominant mite species, and a positive association was found between L. nuttalli and L. echidninus. The curve tendency of species-sample relationship showed that the numbers of mite species still kept increasing without an eventual “platform” stage when the sampled rats reached 1200 individuals, and this implies a great heterogeneity of the mite community on the rat. Preston’s lognormal distribution model successfully fitted the theoretical curve of species abundance distribution of gamasid mites on R. norvegicus, which illustrated the distribution of the dominant, common and rare species of the mites.

Ecological niche divergence between Darevskia rudis and D. bithynica (Lacertidae) in Turkey

Abstract: Darevskia rudis (Bedriaga, 1886) and D. bithynica (Mehely, 1909) are morphologically different species, but they are phylogenetically same species in the D. rudis complex. These species are distributed in northern of Turkey. In the present study, we have evaluated taxonomic status of D. rudis and D. bithynica using ecological niche differentiation. All occurrence data of these species were used to predict and evaluate the suitable areas where they may be expected to be found in Turkey. In order to compare their ecological niches and explain ecological differentiation, niche similarity tests (niche identity and background tests) and point-based analyses were performed. According to results of ecological niche modeling, we found niche differentiation between D. rudis and D bithynica. Ecological niches for the two species differentiated along environmental variables, as precipitation of driest quarter for the two species were most important in determining habitat suitability. This factor is important in niche differentiation between the two species. Finally, our results confirmed the niche differentiation between D. rudis and D. bithynica and added new insights into the taxonomic distinction between D. rudis and D. bithynica that they are two species.

Copper-induced changes in growth, photosynthesis, antioxidative system activities and lipid metabolism of cilantro (Coriandrum sativum L.)

Abstract: The present study aims to investigate the effect of copper (as CuSO4, 5H2O) supply (0, 25 and 50 μM) on performance of cilantro (Coriandrum sativum L.) plants grown under hydroponic conditions. All applied Cu concentrations drastically reduced the biomass production, length of the shoots and the roots and disturbed the ions (Cu, Ca, Fe, Zn and Mg) homeostasis. Either Cu-starvation (0 μM) or Cu-toxicity (25 and 50 μM) significantly reduced the net photosynthetic rate, stomatal conductance and transpiration rate resulting in reduced water use efficiency. Under Cu-toxicity, the variations in gas exchange parameters were associated with a remarkable decline in the photosynthetic pigments including Chlorophyll a, Chlorophyllb, Chlorophyll (a + b) and carotenoids. Additionally, an enhanced lipid peroxidation (evaluated as Malondialdehyde (MDA) contents) with a concomitant increase in proline, total soluble sugars and melanoidins contents were observed under these conditions. The increased MDA levels resulted in decrease in total lipid content and alteration of the fatty acid profiles in both shoots and roots with a general tendency toward the accumulation of saturated fatty acids that mirrors a decline in the desaturases activity. Although the increased activity of enzymatic antioxidants including catalase (CAT), gaiacol peroxidase (GPX) and ascorbate peroxidase (APX), the oxidative-induced injuries caused by 25 and 50 μM Cu were found to be irreversible and the optimal growth parameters were not achieved.