ABSTRACTS 2020 #1                                  
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Sihem RAHALI-OSMANE, Kerima BOULAHIA, Réda DJEBBAR, Ouzna ABROUS-BELBACHIR

Abstract. This work was aimed to study the effects of salt stress induced by increasing concentrations of sodium chloride (NaCl): 50, 100 and 150 mM on cowpea plants (Vigna unguiculata L.). The results showed that higher levels (100 and 150 mM) of NaCl significantly affected the growth by reducing shoot height, leaf area and shoot dry weight of plants. At the cellular level, the salt induced a decline in relative water content correlated to an accumulation of proline in leaves. This accumulation was shown to be related to an over expression of P5CS gene (Δ1-pyrroline 5 carboxylate synthase) and to ProDH (proline dehydrogenase) gene expression which remained at a low level for all salt treatments. Increasing salinity had also decreased photosynthetic pigments; both total chlorophyll and carotenoids contents declined by 40 % under 150 mM NaCl. The effect of oxidative stress induced by salt stress on cowpea plants was determined by evaluating the membrane integrity of cells; the results revealed that salinity increased up to 50% the malondialdehyde content in leaves as well as the electrolytes leakage in plants grown on 150 mM NaCl compared to controls. However, the oxidative damages seemed to be counterpoised by increasing the catalase and ascorbate peroxidase activities in stressed plants. Besides, at transcriptional level, no variation in mitochondrial (AOX2b) and plastidial (PTOX) alternative oxidases genes expression was recorded.

Keywords: Vigna unguiculata; salt stress; proline; ProDH; P5CS; antioxidant enzymes.




Chandima SAMARASINGHE, Monica MARIAN, Levente ALMASI, Nirodha SENEVIRATHNE, Gehan JAYASURIYA

Abstract. Recalcitrant seed-producing species occur even in temperate ecosystems. These species disperse seeds in autumn, while germination occurs in spring. “What proportion of seeds maintains viability over the winter?” was always a question. A research was conducted to evaluate the seed moisture content (SMC) and the viability of two recalcitrant and three orthodox species exposed to winter conditions. Seeds were collected from a forest near Baia-Mare, Cluj-Napoca, Romania and transported to the Department of Chemistry and Biology, North University Center of Baia-Mare. Experiments were initiated within 2 days. Seed coat ratio (SCR) was calculated to predict seed desiccation sensitivity. Seed germination was studied at 25oC in light/dark (12 /12hr) conditions to evaluate viability. SMC of all the species was determined using the oven-dry method. According to the SCR test, probability of Quercus rubra and Q. petraea seeds to be recalcitrant was >0.5 confirming the recalcitrant storage behaviour. Further, SMC of these two species was >20% indicating that they are capable of maintaining high SMC even after exposure to winter conditions. Except for Gleditsia triacanthos, >50% of intact seeds of the studied species germinated, revealing that two recalcitrant seed-producing species had the ability to maintain viability even under winter conditions similar to the orthodox species tested. Scarified G. triacanthos seeds germinated >80% indicating that they have physical dormancy even they were exposed to winter conditions for 3 months. It can be concluded that a high proportion of recalcitrant seeds can survive after going through winter similar to orthodox seeds.

Keywords: desiccation sensitive; longevity; orthodox; recalcitrant




Campbell Onyeka AKUJOBI, Henry Uzoma ANUFORO, Josephat Nwabueze OKEREKE, Chinyere IBEH, Chioma Joy AGBO

Abstract. Optimization of process parameters is crucial to the deployment of nanotechnology as a competitive source of novel materials to many fields. The present study has lent credence to the simplicity, environmental friendly, cost effective and quick potentials of using plant extracts as source of capping and stabilization agents in the synthesis of silver nanoparticles (AgNPs). Aqueous leaf extracts of Mangifera indica and Prunus dulcis were used in synthesis of silver nanoparticles. The study was designed with Box Behnken Design (Minitab® 17) to optimize temperature (25 – 35°C), pH (6 – 8) and time of reaction (6 – 24hours). Fifteen runs were obtained for each sample which determined the value of each parameter used for the synthesis. Results obtained were subjected to Response Optimizer (Minitab® 17) which predicted optimum conditions for synthesis of silver nanoparticles as 25°C at pH 8 and 10.24 hours with predicted maximum yield of 2.53 for Prunus dulcis. However, the actual yield of silver nanoparticles under these conditions was 2.64. For Mangifera indica leaf extract, the predicted optimum conditions were 31.4°C at pH of 8.0 and 9.39 hours with predicted maximum yield of 2.55. Nevertheless, the actual yield under the optimum conditions was 2.61. Results show that Prunus dulcis extract has relatively higher potential yield for silver nanoparticles than Mangifera indica extracts. UV-Vis spectrophotometer showed that the absorbance for synthesized silver nanoparticles using both plant extracts peaked between 400 – 430nm. Silver nanoparticles from both plants showed activity against Bacillus subtilis and Pseudomonas aeruginosa, though B. subtilis was more sensitive. However, silver nanoparticle from Prunus dulcis was less effective against the bacteria.

Keywords: nanotechnology; green synthesis; leaf extracts; parameters.




Cristina STANCĂ-MOISE, Tom BRERETON

Abstract. Research on the ecology, distribution and monitoring of the forest pest Lymantria monacha (L. 1758) (Nun Moth) has been carried out in recent years by authors in various forest areas of Sibiu county. In this study we describe the ecology, distribution and abundance of the species L. monacha, related to climatic factors in each year of study, within the Rasinari Forest. For a comparative analysis of the results obtained from the number of captured specimens of this pest, we centralized the data related to the number of traps located within the forest, the maximum number of butterflies captured in the traps and the total number of butterflies counted during the period 2005-2018. Also, there are presented aspects related to the physico-geographic conditions, climate, maximum and minimum and the composition of the stands, as well as methods for limiting the populations with the help of pheromonal traps and proposals regarding the management of this dangerous pest which is currently latent, but in the future it can extend into the perimeter of the Rășinari Forestry.

Keywords: pheromonal traps, Lymantria monacha (L., 1758), Forest Range Rășinari (Sibiu county, Romania)




Henry Uzoma ANUFORO, Campbell Onyeka AKUJOBI, Paschaline Kenechi UMEH, Paschaline Ifunanya EJIMADU

Abstract. Vehicular traffic has been implicated in increasing heavy metals concentrations in nearby soils. Notably, severe environmental and health challenges have been associated with elevated concentrations of these heavy metals, hence the need to monitor them in adjoining farmlands to forestall entry into food chains. The distribution patterns of Pb, Cd, Mn and Cu on OwerriOnitsha and Owerri-Aba expressways were studied. Soil and Panicum maximum leaf samples were collected at 3 locations on each road at 5m, 10m and 15m away from the roadsides. Samples were processed and analysis for heavy metal concentrations was done with atomic absorption spectrophotometer (AAS). Results obtained indicated the presence of all the selected heavy metals at almost all the locations and points studied. The order for heavy metals in samples from Owerri-Aba expressway was Pb>Cu>Cd>Mn, while that of Owerri-Onitsha was Mn>Pb>Cu>Cd. Although the concentrations generally fluctuated with increasing distance away from the roadsides at most locations, in some grass samples it increased with distance. There was also a decline in their concentrations with increasing distance away from the road for some soil samples. Owerri-Onitsha expressway gave higher concentrations of heavy metals in both samples than Owerri-Aba expressway. Meanwhile, the concentrations of Mn and Cu in plant extracts were generally below the maximum allowable levels while Pb and Cd far exceeded it. Similarly, their concentrations in soil samples were below the EU limits except Cd. Results of metal bioaccumulation factor revealed that Panicum maximum moderately bioaccumulated most heavy metals from the soil. There was weak or no correlation between heavy metal contents of soil and P. maximum samples. Atmospheric deposition also contributed to the heavy metals in plant samples. Since some heavy metals studied exceeded their recommended limits, it is advisable to discourage farming activities upto 15m from the roadsides, especially on sloped roadsides.

Keywords: exhaust fumes; roadside; heavy metals; bioaccumulation; distribution; Owerri-Aba road; Owerri-Onitsha road.


 

Lizawati LIZAWATI, Zulkarnain ZULKARNAIN, Neliyati NELIYATI

Abstract. An in vitro protocol for callus proliferation and development of Coffea liberica was developed. Immature leaf sections (1 x 1 cm) were cultured on solid MS medium supplemented with 2,4-D (0, 0.5, 1.0 and 2.0 mg L-1) and 2-iP (0, 1.0, 2.0 and 3.0 mg L-1). Cultures were maintained at temperature of 25 ± 1 °C, light intensity of 50 µmol m-2 s-1 and 16-hours daily photoperiod for 6 months. Callus growth and characteristics were evaluated for 6 months of culture. It was found that the application of 0.5 mg L-1 2.4-D + 2.0 mg L-1 2-iP resulted in the best time for callus induction (13.47 days after culture initiation). The application of 0.5 mg L-1 2.D + 2.0 mg L-1 2-iP and 1.0 mg L-1 2.4-D + 1.0 mg L-1 2-iP resulted in the highest frequency of explant forming callus (56.67% on the average). The morphology of proliferated callus varied from clear, white-creamy, light yellow and brown in color, and friable to compact in structures.

Keywords: Coffea liberica; tissue culture; micropropagation; 2,4-Dichlorophenoxyacetic acid; N6-(2-Isopentenyl) adenine.




Svetlana BOORTSEVA, Maxim BYRSA, Mariana CARAMAN, Irina ACHIRI

Abstract. The paper deals with the results of a research of changes in antimicrobial activity of strain Streptomyces levoris CNMN-Ac-01 on synthetic and complex media after long-term storage by subculturing (10 years). Antimicrobial activity was determined by the disk diffusion method, as test cultures were chosen opportunistic pathogenic bacteria and fungi spread in the Republic of Moldova. It was experimentally proved that the strain lost antimicrobial activity to a greater extent in relation to opportunistic pathogenic fungi, especially after cultivation on a complex medium (by 20.0-23.5%), while on a synthetic medium Czapek it is less (8.37-22.2%). It was established that the strain isolated from the soil of the Republic of Moldova differs from other strains of the same species in its ability to inhibit the growth of such fungi as Aspergillus flavus, Penicillium expansum and strains of the genus Fusarium. Studied strain has the ability to synthesize not only antibiotics levorin and levoristatin, but also probably, and other substances with antifungal activity.

Keywords: Streptomyces levoris; antimicrobial activity; subculturing; long-term storage; synthetic media; complex media




Zakaria BOUAL, Guillaume PIERRE, Abdellah KEMASSI, Said MOSBAH, Fatima BENAOUN, Cédric DELATTRE, Philippe MICHAUD, Mohamed Didi OULD EL HADJ

Abstract. Myrrha, the gum resin exudate from Commiphora myrrha (Nees) Engl. tree, has been extensively used in traditional medicine for their beneficial effects. In this work, we isolated and purified water-soluble polysaccharide fraction (WSP), which afforded a yield of 42%. The chemical composition of WSP was mainly consisted of 83.33±2.63% carbohydrates, among them 79.25±1.06% are neutral monosaccharides and 13.4± 2.18% proteins, with traces of polyphenols (3.82%): The majority components of monosaccharides were galactose (45%) and arabinose (44%), with low levels of xylose (6%), and mannose (5%): In order to evaluate the immunostimulatory effect of WSP, phagocytic activity of opsonized human leucocytes against opportunist pathogen yeast, Candida albicans, was assessed. WSP could significantly (p < 0.05) enhance phagocytic capacity at the dose of 150 µg/ml, which showed a phagocytic activity of 29%. Moreover, the antihyperglycemic activity of extract was determined by α-Dglucosidase inhibitory activity, in vitro. WSP displays a promising inhibitory activity with an IC50 value of 8.30±0.12 mg/mL. The results of this work provide new knowledge in the field of chemical composition and biological activities of polysaccharides of Commiphora myrrha gum and might play an important role in activating phagocytosis leucocytes cells, thus having contribution to antidiabetic activity.

Keywords: Myrrha; traditional; gum; polysaccharide; biological activities.




Hamid BACHIRI, Réda DJEBBAR, Arezki MEKLICHE

Abstract. Combined drought and high temperatures are mainly abiotic stress factors that often occur simultaneously in the field and represente an increasing risk to global wheat production. In addition, these environmental challenges lead to oxidative stress in plants through overproduction of reactive oxygen species (ROS). The effects of combined drought and heat on antioxidant enzyme activities were investigated in three wheat genotypes (Triticum aestivum L.). Two Algerian varieties, Ain Abid and Hidhab plus advanced line from CIMMYT, that called in this study V6 genotype, were compared under single and combined (HS x D) stresses of drought (30% field capacity, D) and heat stress (day/night = 23/36 °C, HS) during 7 days. Results showed that, heat stress (HS), drought (D) or combined of HS x D severely reduces growth, biomass (dry matter), with greater effect observed in response to HS x D by -58.38% as mean reduction for all genotypes. However, V6 genotype showed lower increase in malondialdehyde (MDA) concentration in response to single drought and heat stress that is closely associated with higher activity of CAT under drought (+304.79%) and APX activity under heat stress (+179.23%). While under combined of HS x D only V6 genotype showed efficient up-regulation of APX activity (+288.27%) that is followed by no significant oxidative damage (MDA). In contrast, Hidhab variety revealed inefficient increased of APX in response to combined of HS x D that is demonstrated by higher significant increase of MDA concentration. Similarly, in response to single drought (D), Ain Abid variety had inefficient up-regulation of CAT and the overproduction of peroxides might lead to membrane dysfunction that is a consequence of hydrogen peroxide accumulation due to loss in APX activity (-8.5%). Thus, our results suggest that tolerance of V6 genotype to drought, heat stress or their combined effect is strongly related with efficient modulation between antioxidant enzyme activities, less MDA concentration and increased CAT and APX activities to scavenge hydrogen peroxide in the plant cell.

Keywords: wheat genotype (Triticum aestivum L); drought; heat; oxidative stress and antioxidant enzymes.




Cezara BIVOL, Alexandra CILOCI, Janetta TIURINA, Steliana CLAPCO, Svetlana LABLIUC, Elena DVORNINA, Ana LAZARESCU, Veaceslav REVA

Abstract. The influence of Cu(H2L)Cl] complex on proteolytic activity of T. koningii Oudem. CNMN FD 12 fungal strain was evaluated during the 7-11 days of cultivation. The stimulatory effect of the concentrations of 5-15 mg/L of metal complex on the activity of neutral and acid proteases was observed. The peak of acid and neutral protease activity was determined on the 9th and 10th day of cultivation, similar to the control sample. The most favorable concentration of Cu(H2L)Cl] was 10 mg/L. Following purification of the proteases by gel filtration resulted in an increase of the specific activity of the control preparation of 1.3-1.7 times for neutral proteases and 1.3-1.8 times for acid proteases. The overall yield, determined for fractions with proteolytic activity, constituted 19% for neutral proteases, and 21% for acid proteases. Purification of the optimized preparation showed an increase in specific activity of the neutral protease of 0.8-1.3 times and of the acid proteases of 1.5-1.7 times. The overall yield was 12.2% for neutral proteases and 18.8% for acid proteases. SDS-PAGE electrophoresis of isolated proteins from the chromatographic fractions showed polypeptide bands only in proteolytic active fractions. Some new polypeptides with apparent molecular mass of 51 and 49 kDa appeared in the polypeptide profile of optimized preparation. The changes were most likely induced by the utilization of [Cu(H2L)Cl] coordination compound in the T. koningii cultivation process.

Keywords: Trichoderma koningii; protease; coordination compound; enzyme purification; SDS-PAGE.




Atilade Adedayo ADEDEJI, Olubukola Oluranti BABALOLA

Abstract. Several attempts have been made by researchers to evaluate the abundance and distribution of microorganisms in the soil following the first discovery and publication of the estimated number of prokaryotes that could be occupying the soil. Many described this information based on the relatedness of the community structure to the function of ecosystem. It was revealed that the amount and heterogeneity of microbial species inhabiting the soil are significant for the continued sustenance of plant growth and development, as a broad assortment of microbes are involved in vital soil functions. Current studies further explain the roles of the rhizosphere in defining the arrangement and composition of the soil microbes, the ability of plants to specifically shape their microbial community, the interplay between plants and soil in shaping their community. Furthermore, the bulk of soil microbes are yet to be cultured and their functions still largely unknown. With the advent of molecular biology, there is a growing concern about the possible effects of difficult-to-culture microbial species in soil environments and the contributing factors to their dynamics. This review consequently deploys old and recent molecular tools in describing these variables and introduces metagenomics as a modern tool to unravel the dynamics and community functional potential focusing on up-to-date data in describing them.

Keywords: exudates; metagenomics; rhizosphere; root signaling; microbiome.




Agim HAZIRI, Ema OLLOMANI

Abstract. Sambucus deborensis Košanin, is a threatened species that grows in a restricted area near Debar. From the national CORINE list, 19 local endemic species are present in North Macedonia, where one of them is also this species. From the current knowledge of flora in North Macedonia, Sambucus deborensis Košanin is presented only in a locality around the road south of Debar (676 m, 41°31'28"N, 20°31'36"E, 40-50 m2). In the case of widening the road, it could be seriously endangered or even disappeared. During the floristic researches in this territory near Debar, another new locality, was recognized which represents a new record of distribution of this species in the flora of North Macedonia. The new location (671 m, 41°31'24"N, 20°31'38"E, July 28, 2019) is about 1.5 km from the old locality. It has a significantly smaller surface area, and is constantly being damaged by urban construction. The discovery of this new locality is very important for this endangered species, but the relevant state institutions must urgently commit to protecting this species from illegal construction in this locality.

Keywords: Sambucus deborensis Košanin; Debar; new locality; Republic of North Macedonia.




Wassila HAMDI, Asma RAMDANE, Hadjer DJOUMAAT, Zineb HELLOU, Mohamed Didi OULD EL HADJ

Abstract. Dates can be used as a raw material for the production of vinegar. This vinegar has significant interests in food, industry and health. Thus, acetic acid bacteria (AAB) introduced in the process of making traditional date vinegar (TDV), ensure its acidity. Six (6) pure strains of AAB Acetobacter aceti subsp. aceti, Acetobacter aceti subsp. liquifaciens, Acetobacter aceti subsp. orleanensis, Acetobacter pasteurianus subsp. ascendens, Acetobacter pasteurianus subsp. lovaniensis and Gluconobacter oxydans subsp. industrius isolated from traditional date vinegars (TDV) of the cultivars Deglet-Nour, Hamraya and Harchaya from the Ouargla basin, are biochemically tested to see their tendency to assimilate some hydrocarbon substrates in the form of miniaturized galleries (API 20 Strep and API 20 NE) . These strains are thus cultivated in a liquid medium based on yeast extract, glucose, ethanol and acetic acid (GYEA), modified with 2% to 10% ethanol and acetic acid, to test their resistance under industrial conditions. The tests are used to select the strains that perform best in acetic acid production (vinegar) and ensure their survival during the process. Two strains Acetobacter aceti subsp. orleanensis and Acetobacter pasteurianus subsp. lovaniensis can assimilate the majority of carbohydrate substrates which represents 66.67% (08 substrates). The strains grown in GYEA medium showed a total tolerance of 2% to 10% ethanol, but Acetobacter aceti subsp. aceti and Acetobacter aceti subsp. liquifaciens have very good growth at 10%. With acetic acid added to bacterial cultures, resistance to the condition is moderate between 2% and 10%, but the two strains Acetobacter aceti subsp. aceti and Acetobacter aceti subsp. orleanensis, are the most acidophilic at 10%. Acetobacter aceti subsp. aceti is the most suitable strain with ethanol and acetic acid stress. So it is the most profitable and likely to be able to withstand the incidents of the vinegar industry. This offers a choice for large industrial scale applications.

Keywords: Traditional date vinegar; acetic acid bacteria; Acetobacter; Gluconobacter; oxidation; ethanol tolerance; Acidophilia; Algerian Sahara.



 

Abdullah SARDAR, Aboothar ALEDHAR, Mikdad TAHER, Basim ALMAYAHI

Abstract. Umbilicus tropaeolifolius subsp. zalamica Sardar et Al-Edhari (Crassulaceae) is described as a subspecies to science based on the material collected from Zalam region (South East of Sulaimaniya). Morphologically it is close to the typical U. tropaeolifolius Boiss. which is a species found in Iraq. An identification and a taxonomic description are given.

Keywords: Umbilicus; taxa; Zalam; Sulaimania; Iraq 





Mina TAGHIZADEH , Fahimeh Sadat SAJADI

Abstract. Kentucky bluegrass is one of the most important species of cold season grass which is used in mixed sports turfgrass. This study was conducted to determine the effect of plant growth regulators on callus induction and plant regeneration from hypocotyl explants in Kentucky bluegrass. For this purpose, the MS media containing two auxins (2,4-D and NAA) at different concentrations of 0.5, 1, 2, 3, 4 and 5 mg/L were used alone or in combination with and without the 0.1 mg/ L Benzyladenine (BA). The results showed that the highest callus induction rate was obtained at concentrations of 2 mg/L 2,4-D in combination with 1.0 mg/L BA or 1 mg/L NAA alone. The highest plant regeneration rate was obtained at a concentration of 0.5 mg/L 2,4-D. The protocol we introduced can be used for rapid and scalable micropropagation of this turfgrass species and may also serve as a good platform for for protocol developments of other recalcitrant turfgrasses.

 Keywords: auxin; cytokinins; hypocotyl; turfgrass.

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