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Soil salinization, especially in arid and semi-arid regions, is one of the major abiotic stresses that affect plant growth. To mediate and boost plant tolerance against this abiotic stress, arbuscular mycorrhizal fungi (AMF) symbiosis is commonly thought to be an effective tool. So, the main purpose of this study was to estimate the role of AMF (applied as a consortium of Claroideoglomus etunicatum, Funneliformis mosseae, Rhizophagus fasciculatum, and R. intraradices species) symbiosis in mitigating deleterious salt stress effects on the growth parameters (shoot length (SL), root length (RL), shoot dry weight (SDW), root dry weight (RDW), root surface area (RSA), total root length (TRL), root volume (RV), root diameter (RD), number of nodes and leaves) of Cenchrus ciliaris L. plants through improved accumulations of photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophyll), proline and phenolic compounds. The results of this experiment revealed that the roots of C. ciliaris plants were colonized by AMF under all the applied salinity levels (0, 75, 150, 225, and 300 mM NaCl). However, the rate of colonization was negatively affected by increasing salinity as depicted by the varied colonization structures (mycelium, vesicles, arbuscules and spores) which were highest under non-saline conditions. This association of AMF induced an increase in the growth parameters of the plant which were reduced by salinity stress. The improved shoot/root indices are likely due to enhanced photosynthetic activities as the AMF-treated plants showed increased accumulation of pigments (chlorophyll a, chlorophyll b and total chlorophyll), under saline as well as non-saline conditions, compared to non-AMF (N-AMF) plants. Furthermore, the AMF-treated plants also exhibited enhanced accumulation of proline and phenolic compounds. These accumulated metabolites act as protective measures under salinity stress, hence explaining the improved photosynthetic and growth parameters of the plants. These results suggest that AMF could be a good tool for the restoration of salt-affected habitats. However, more research is needed to check the true efficacy of different AMF inoculants under field conditions. [ABSTRACT FROM AUTHOR]

Tissue culture is used to multiply Al-Taif rose (Rosa damascena f. trigintipetala (Diek) R. Keller) plants in order to meet the demands of the fragrance, cosmetic, and floriculture industries. The use of arbuscular mycorrhizal fungus (AMF) could potentially improve plant growth and acclimatization performance to ex vitro conditions. Thus, in the current study, we investigated how AMF Rhizophagus fasciculatus influences the growth, establishment, and physiological performance of micropropagated Al-Taif rose plants during the acclimatization stage. The growth and physiological parameters of the AMF-treated plants were evaluated after a 12 week growth period in the growth chambers. The plants treated with AMF exhibited greater height (25.53 cm) and biomass growth values for both shoot fresh weight (0.93 g/plant) and dry weight (0.030 g/plant), more leaves (11.3/plant), more leaf area (66.15 cm2), longer main roots (15.05 cm/plant), total root length (172.16 cm/plant), total root area (64.36 cm2/plant), and biomass from both fresh weight (383 mg/plant) and dry weight (80.00 mg/plant) of the plants. The plants treated with AMF also exhibited increased rates of net CO2 assimilation, stomatal conductance, and transpiration compared to the control plants. The proline content in the leaves and roots was significantly lower in the AMF-treated plants than untreated plants. The Fv/Fm ratio, which serves as an indicator of the intrinsic or maximal efficacy of Photosystem II (PSII) demonstrated a notable decline in the untreated Al-Taif rose plants. These results elucidate the advantageous impact of AMF colonization on micropropagated Al-Taif rose plants, thereby enhancing their resilience against adverse ex vitro conditions. [ABSTRACT FROM AUTHOR]

Abstract Mud crab belongs to the genus Scylla is an economically valuable and preferred species for costal aquaculture in Asian countries, including India. In recent years, there has been a tremendous expansion of Scylla farming, which has led to increasing research on its habit and habitats. However, there has been no study undertaken to understand the role of the bacterial population associated with the different organs of the mud crab, Scylla olivacea. In total, 43 isolates were recovered from four selected parts of the crab (carapace, n = 18; abdomen n = 11; leg, n = 8; and hand, n = 6), and the 16S rRNA gene was used to identify the bacterial isolates. The antimicrobial potential along with the detection of modular polyketide synthase (PKSI), cytochrome P450 hydroxylase (CYP) and non-ribosomal peptide synthetase (NRPS) gene clusters were investigated to show a relationship among the biosynthetic genes with their useful aspects. Additionally, the potential three strains (BPS_CRB12, BPS_CRB14 and BPS_CRB41), which showed significant antimicrobial activities, also showed the presence of twenty volatile compounds (VOCs) using GC–MS analysis. We conclude that the strain Aneurinibacillus aneurinilyticus BPS_CRB41 could be source for the production of bioactive compounds. [ABSTRACT FROM AUTHOR]

Plant growth-promoting endophytic bacteria can stimulate the growth, nutrient acquisition, symbiotic performance and stress tolerance of chickpea plants under saline soil conditions. The aim of this study was to investigate the stress-adaptive mechanisms of chickpea plants mediated by Bacillus subtilis (BERA 71) under saline conditions. Inoculation with BERA 71 enhanced plant biomass and the synthesis of photosynthetic pigments and reduced the levels of reactive oxygen species (ROS) and lipid peroxidation in plants under conditions of stress. Furthermore, the activities of ROS-scavenging antioxidant enzymes (superoxide dismutase, peroxidase, catalase and glutathione reductase), the levels of non-enzymatic antioxidants (ascorbic acid and glutathione) and the total phenol content were increased in stressed plants during bacterial association. The bacteria decreased sodium accumulation and enhanced the nitrogen, potassium, calcium and magnesium content in the plants. The suppression of ROS generation and of lipid peroxidation and the accumulation of proline in BERA-71-inoculated plants enhanced the membrane stability under salinity stress and non-stress conditions. [ABSTRACT FROM AUTHOR]

The performances of silicate glassesas containment matrices orvectors of radioactive ions in nuclear waste storage and in situ radiotherapyare influenced by the effect of interstitial water on the glass durability.In order to assess how hydration determines changes to atomistic structuralfeatures which control the glass degradation, we have carried outmolecular dynamics simulations of a typical yttrium aluminosilicate(YAS) glass employed in radiotherapy, incorporating different watercontents. The analysis of the models allows us to discuss the wayin which hydroxyl groups are distributed in the glass structure andmodify or disrupt the aluminosilicate glass network. Hydration affectsthe silicate and aluminate connectivity to a different extent, resultingin a different degree of disruption (depolymerization) of the Si andAl network. The simulations also highlight a strong tendency of allhydrated compositions to form Y3+- and OH–-rich domains, separated from the aluminosilicate matrix. The implicationsof these structural effects for the durability and ion release behaviorof the glass are discussed, as well as the vibrational signaturesof the various hydrous species identified in the models. [ABSTRACT FROM AUTHOR]

The incorporation of yttrium in bioactive glasses (BGs) could lead to a new generation of radionuclide vectors for cancer therapy, with high biocompatibility, controlled biodegradability and the ability to enhance the growth of new healthy tissues after the treatment with radionuclides. It is essential to assess whether and to what extent yttrium incorporation affects the favourable properties of the BG matrix: ideally, one would like to combine the high surface reactivity typical of BGs with a slow release of radioactive yttrium. Molecular Dynamics simulations show that, compared to a BG composition with the same silica fraction, incorporation of yttrium results in two opposing effects on the glass durability: a more fragmented silicate network (leading to lower durability) and a stronger yttrium-mediated association between separate silicate fragments (leading to higher durability). The simulations also highlight a high site-selectivity and some clustering of yttrium cations, which are likely linked to the observed slow rate of yttrium released from related Y-BG compositions. Optimisation of yttrium BG compositions for radiotherapy applications thus depends on the delicate balance between these effects. [ABSTRACT FROM AUTHOR]