Preliminary results on quinoa (Chenopodium quinoa Willd.) cultivated in Tunisian Semi-Arid area under drought and salinity conditions

Most of arid regions, as Tunisian area, are threatened by environmental changes considering the shortage of water resources and the low quality of water that is used for crop irrigation. To ensure food security under this current context, there is a need to search for new crops with high economic value and adapted to extreme climatic condition like quinoa (Chenopodium quinoa Willd). A program was started from 2014 to study the responses of quinoa under Tunisian drought and salinity constraints. A preliminary study was carried out under greenhouse using two experiences. For the first, quinoa plants were irrigated by fresh water (1.25 dS.m-1) with three frequencies: 3, 7 and 12 days. For the second, quinoa plants were irrigated with four quality of saline water: 1.25, 10, 25 and 40 dS.m-1 to analyze the effect of both drought and salinity stress on morphological and physiological parameters of quinoa. In 2015, another study was done in plot where we interested ourselves in the effect of two different irrigation management strategies on the growth and the nutritional value of quinoa seeds. The first group grew under different deficit regimes with 100%, 70% and 50% water requirements. The irrigation water of the second group contained different amounts of salt (Fresh water: 0.9 g.l-1, 6 g.l-1 and 12 g.l-1). In this paper, we focus on the preliminary result of salinity stress of the second part where we found out that the irrigation with 6 g.l-1 of salt content increased seeds yield weight from 8.43 g per plant to 20.57 g per plant, the 1000 seeds weight from 1.85g to 2.34 g compared to the control. The mineral composition of the plant irrigated with saline water showed an increase in Na+ content in seeds but also an important variation of the majority of macroelements (P, K+, Ca2+, Mg2+). (Résumé d'auteur

Phytochemical screening, antioxidant, analgesic and acetylcholinesterase inhibitory effects of Pittosporum tobira leaves

The objective of this study was to determine in the first time the phytoconstituents and the in vitro antioxidant and enzyme inhibitory properties of the ethanol extract of P. tobira leaves (PTL) and to assess its in vivo pharmacological action on pain.Phytochemical screening was done using standard protocols. The antioxidant potential was investigated using two methods including hydrogen peroxide and DPPH radical-scavenging assays. An assessment of the anti-acetylcholinesterase activity of PTL was performed. The analgesic activity was also evaluated using a hot plate and acetic acid assays.Alkaloid, saponins, cardiac glycoside, terpenoids, flavonoids and reducing sugars were found to be present in the leaf of P. tobira. PTL showed a significant antioxidant capacity by inhibition of DPPH radical (EC50 = 143.4 µg/mL) and H2O2 (EC50 = 46.29± 2.1 µg/mL) scavenging activities. Moreover, acetylcholinesterase enzyme was strongly inhibited by PTL with the IC50 value of 100.79 µg/mL. The analgesic effect of PTL was evaluated in mice after intraperitoneal injection of acetic acid (1%, 10 mL/kg, ip). The results showed that PTL reduced significantly the abdominal writhing in mice with an inhibition percentage of 14.78%, comparable with standard paracetamol (10.31%). Furthermore, PTL (350 mg / kg) increased remarkably the reaction time of mice with relatively extended duration of stimulation in the hot-plate test when compared to the control groups.We conclude that the leaf extract of P. tobira possesses potential antioxidant, anti-nociceptive, and anti-acetylcholinesterase properties which could be assigned to the presence of bioactive compounds in its composition

Isolation, Identification, and Characterization of Phosphate-Solubilizing Bacteria from Tunisian Soils

Soil microorganisms play an important role in maintaining natural ecological balance through active participation in carbon, nitrogen, sulfur, and phosphorous cycles. Phosphate-solubilizing bacteria (PSB) are of high importance in the rhizosphere, enhancing the solubilization of inorganic phosphorus complexes into soluble forms available for plant nutrition. The investigation of this species of bacteria is of major interest in agriculture, as they can be used as biofertilizers for crops. In the present study, 28 isolates of PSB were obtained after the phosphate enrichment of soil samples from five Tunisian regions. Five PSB species were identified by 16S rRNA gene sequencing including Pseudomonas fluorescens, P. putida, and P. taiwanensis, Stenotrophomonas maltophilia, and Pantoea agglomerans. Solid and liquid Pikovskaya’s (PVK) and National Botanical Research Institute’s (NBRIP) media containing insoluble tricalcium phosphate were used for the evaluation of the phosphate solubilization ability of the bacterial isolates by two methods: visual evaluation of the solubilization zone around colonies (halo) and determination of solubilized phosphates in liquid medium by the colorimetric method of the vanado-molybdate yellow. Based on the results of the halo method, the isolate of each species that showed the higher phosphate solubilization index was selected for evaluation of phosphate solubilization by the colorimetric method. In the liquid media, the bacterial isolates showed phosphate solubilization ranging from 535.70 to 618.57 µg mL−1 in the NBRIP medium, and 374.20 to 544.28 µg mL−1 in the PVK medium, with the highest values produced by P. fluorescens. The best phosphate solubilization ability and higher reduction in broth pH, which indicates higher organic acid production, were achieved in NBRIP broth for most of the PSB. Strong correlations were observed between the average capability of PSB to solubilize phosphates and both the pH and total phosphorous content in the soil. The production of the hormone indole acetic acid (IAA), which can promote plant growth, was observed for all five PSB species. Among them, P. fluorescens obtained from the forest soil of northern Tunisia showed the highest production of IAA (50.4 ± 0.9 µg mL−1).This research was partially supported by the Smart Cities Research Center under the grant UIDB/05567/2020 funded by The Portuguese Foundation for Science and Technology (FCT—Fundação para a Ciência e a Tecnologia, Portugal). The authors wish to acknowledge the Ministry of Higher Education and Scientific Research in Tunisia, which has facilitated the work performed.info:eu-repo/semantics/publishedVersio

A review of recent studies on the life history and ecology of European cephalopods with emphasis on species with the greatest commercial fishery and culture potential

With the depletion of many commercial fish stocks and an increasing demand for marine protein for human consumption, cephalopods have become more important as a fishery resource. In EU waters, cephalopod stocks are not routinely assessed and exploitation of these species by large-scale fisheries is largely unregulated. For sustainable exploitation, adequate assessment and scientifically-supported management strategies are needed. However, there is still a lack of data on stock status and inadequate knowledge of the life history and ecology of these species. The present review examined more than 200 scientific articles, on life history and ecology of European cephalopods, published since 2013. It describes recent contributions to knowledge in the context of previously identified research priorities, along with recent advances towards sustainable fishing and aquaculture. It also identifies outstanding knowledge gaps. While some priority areas, such as the development of the species identification guides and evaluation of climate change impacts on cephalopods, have seen significant advances, other challenges remain for the future. These include monitoring of the life history traits and fishery status for the main commercially exploited species in the area, implementation of improved species identification methods during scientific surveys and fisheries monitoring, development of tools to identify stock units, and the study of the environmental and anthropogenic impacts on the stocks of cephalopods inhabiting European waters.Versión del edito

Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429):Trypanosoma evansi infections (including Surra)

Abstract Trypanosoma evansi infections (including Surra) have been assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of Article 7 on disease profile and impacts, Article 5 on the eligibility of T. evansi infections (including Surra) to be listed, Article 9 for the categorisation of T. evansi infections (including Surra) according to disease prevention and control rules as in Annex IV and Article 8 on the list of animal species related to T. evansi infections (including Surra). The assessment has been performed following a methodology composed of information collection and compilation, expert judgement on each criterion at individual and, if no consensus was reached before, also at collective level. The output is composed of the categorical answer, and for the questions where no consensus was reached, the different supporting views are reported. Details on the methodology used for this assessment are explained in a separate opinion. According to the assessment performed, it is inconclusive whether T. evansi infections (including Surra) can be considered eligible to be listed for Union intervention as laid down in Article 5(3) of the AHL because there was no full consensus on the criterion 5 A(v). Consequently, the assessment on compliance of T. evansi infections (including Surra) with the criteria as in sections 4 and 5 of Annex IV of the AHL, for the application of the disease prevention and control rules referred to in points (d) and (e) of Article 9(1) is also inconclusive, as well as which animal species can be considered to be listed for T. evansi infections (including Surra) according to Article 8(3) of the AHL

Does co-infection with vector-borne pathogens play a role in clinical canine leishmaniosis?

The severity of canine leishmaniosis (CanL) due to Leishmania infantum might be affected by other vector-borne organisms that mimic its clinical signs and clinicopathological abnormalities. The aim of this study was to determine co-infections with other vector-borne pathogens based on serological and molecular techniques in dogs with clinical leishmaniosis living in Spain and to associate them with clinical signs and clinicopathological abnormalities as well as disease severity. Sixty-one dogs with clinical leishmaniosis and 16 apparently healthy dogs were tested for Rickettsia conorii, Ehrlichia canis, Anaplasma phagocytophilum and Bartonella henselae antigens by the immunofluorescence antibody test (IFAT) and for E. canis, Anaplasma spp., Hepatozoon spp., Babesia spp. and filarioid DNA by polymerase chain reaction (PCR). Among the dogs examined by IFAT, the seroprevalences were: 69% for R. conorii, 57% for E. canis, 44% for A. phagocytophilum and 37% for B. henselae ; while the prevalences found by PCR were: 8% for Ehrlichia / Anaplasma, 3% for Anaplasma platys and 1% for H. canis. No other pathogen DNA was detected. Statistical association was found between dogs with clinical leishmaniosis and seroreactivity to R. conorii antigen (Fisher's exact test: P = 0.025, OR = 4.1, 95% CI = 1-17) and A. phagocytophilum antigen (Fisher's exact test: P = 0.002, OR = 14.3, 95% CI = 2-626) and being positive to more than one serological or molecular tests (co-infections) (Mann-Whitney test: U = 243, Z = -2.6, n = 14, n = 61, P = 0.01) when compared with healthy dogs. Interestingly, a statistical association was found between the presence of R. conorii, E. canis, A. phagocytophilum and B. henselae antibodies in sick dogs and some clinicopathological abnormalities such as albumin and albumin/globulin ratio decrease and increase in serum globulins. Furthermore, seroreactivity with A. phagocytophilum antigens was statistically associated with CanL clinical stages III and IV. This study demonstrates that dogs with clinical leishmaniosis from Catalonia (Spain) have a higher rate of co-infections with other vector-borne pathogens when compared with healthy controls. Furthermore, positivity to some vector-borne pathogens was associated with more marked clinicopathological abnormalities as well as disease severity with CanL