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Hypersaline ecosystems are distributed all over the globe. They are subjected to poly-extreme stresses and are inhabited by halophilic microorganisms possessing multiple adaptations. The halophiles have many biotechnological applications such as nutrient supplements, antioxidant synthesis, salt tolerant enzyme production, osmolyte synthesis, biofuel production, electricity generation etc. However, halophiles are still underexplored in terms of complex ecological interactions and functions as compared to other niches. The advent of metagenomics and the recent advancement of next-generation sequencing tools have made it feasible to investigate the microflora of an ecosystem, its interactions and functions. Both target gene and shotgun metagenomic approaches are commonly employed for the taxonomic, phylogenetic, and functional analyses of the hypersaline microbial communities. This review discusses different types of hypersaline niches, their residential microflora, and an overview of the metagenomic approaches used to investigate them. Various applications, hurdles and the recent advancements in metagenomic approaches have also been focused on here for their better understanding and utilization in the study of hypersaline microbiome.

Aims: Climate change is responsible for extreme cold winters, causing a significant loss in crop yield and productivity due to chilling stress. This study aims to investigate the potential of psychrotrophic plant growth-promoting rhizobacteria (PGPR) strain to promote wheat growth under cold stress and explore the adaptive responses of wheat., Methods and Results: Wheat seeds and seedlings were inoculated with the psychrotrophic strain IRS14 and the plants were cultivated for five weeks at 6°C ± 2°C. The genetic, biochemical, physiological, and molecular analysis of the bacterium and plant was done to evaluate the effect of the PGPR strain in alleviating chilling stress. IRS14 possesses antioxidant activity and produced multiple phytohormones, which enhanced seed germination (∼50%) and plant growth (∼50%) during chilling stress., Conclusions: Here, we reported that the application of IRS14 helps to regulate the biochemical and metabolic pathways in wheat plants. It alleviates chilling stress and increases plant growth rate and biomass. Strain IRS14 in wheat effectively increased chlorophyll content, antioxidants, carotenoid, proline, and endogenous phytohormones compared with untreated wheat., (© The Author(s) 2023. Published by Oxford University Press on behalf of Applied Microbiology International.)

The reactions of [Zn 3 Cl 2 (3,5-Me 2 PzH) 4 ( t -BuPO 3 ) 2 ] with organostibonic acid in varying reaction conditions have been investigated. Single-crystal X-ray diffraction studies reveal the formation of [Zn 2 ( p -ClC 6 H 4 Sb) 2 (O) 2 (OCH 3 ) 2 ( t -BuPO 3 ) 3 (py) 2 ] ( 1 ), [Zn 2 ( p -ClC 6 H 4 Sb V ) 4 (Sb III ) 2 (O) 8 ( t -BuPO 3 H) 4 ( t -BuPO 3 ) 2 (py) 2 Cl 2 ] ( 2 ), and [Zn 2 (RSb) 4 (O) 4 (OCH 3 ) 4 ( t -BuPO 3 ) 4 (py) 2 ], where R = p -ClC 6 H 4 ( 3 ) and R = p -iPrC 6 H 4 ( 4 ), respectively. Interestingly, in the synthesis of 2 , complete dearylation of organoantimony moieties followed by C-F bond formation, a reduction from Sb (V) to Sb (III), and Sb···Cl weak intermolecular interactions have been observed. ESI-MS studies suggested that clusters 1 - 4 maintained their structural integrity in the solution state also. Solution NMR studies ( 1 H, 31 P, and 13 C) support well the observed solid-state structures. 1 - 4 were tested for antibacterial activity using a microdilution assay. 1 and 4 showed the best activity with lower MIC values (0.78-6.25 μg/mL) against all the tested pathogens. The total antioxidant activity of 1 - 4 was evaluated through the phosphomolybdenum assay, which showed a total antioxidant activity ranging from 28.96 to 86.46 mg AAE/g compound with the ascorbic acid standard.

The Eastern Himalayas are renowned for their high plant diversity. To understand how this modern botanical richness formed, it is critical to investigate past plant biodiversity preserved as fossils throughout the eastern Himalayan Siwalik succession (middle Miocene-early Pleistocene). Here, we present a summary of plant diversity records that document Neogene floristic and climate changes. We do this by compiling published records of megafossil plant remains, because these offer better spatial and temporal resolution than do palynological records. Analyses of the Siwalik floral assemblages based on the distribution of the nearest living relative taxa suggest that a tropical wet evergreen forest was growing in a warm humid monsoonal climate at the deposition time. This qualitative interpretation is also corroborated by published CLAMP (Climate Leaf Analysis Multivariate Program) analyses. Here, we also reconstruct the climate by applying a new common proxy WorldClim2 calibration. This allows the detection of subtle climate differences between floral assemblages free of artefacts introduced by using different methodologies and climate calibrations. An analysis of the Siwalik floras indicates that there was a gradual change in floral composition. The lower Siwalik assemblages provide evidence of a predominance of evergreen elements. An increase in deciduous elements in the floral composition is noticed towards the close of the middle Siwalik and the beginning of the upper Siwalik formation. This change reflects a climatic difference between Miocene and Plio-Pleistocene times. This review helps us to understand under what paleoenvironmental conditions plant diversity occurred and evolved in the eastern Himalayas throughout the Cenozoic., (© 2022 Kunming Institute of Botany, Chinese Academy of Sciences. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd.)

Here we have identified and characterized a devastating virus capable of inducing yellow mosaic on the leaves of Patchouli [Pogostemon cablin (Blanco) Benth]. The diagnostic tools used were host range, transmission studies, cytopathology, electron microscopy, serology and partial coat protein (CP) gene sequencing. Evidence from biological, serological and sequence data suggested that the causal virus belonged to genus Potyvirus, family Potyviridae. The isolate, designated as Patchouli Yellow Mosaic Virus (PaYMV), was transmitted through grafting, sap and the insect Myzus persicae (Sulz.). Flexuous rod shaped particles with a mean length of 800 nm were consistently observed in leaf-dip preparations from natural as well as alternate hosts, and in purified preparation. Cytoplasmic cylindrical inclusions, pinwheels and laminar aggregates were observed in ultra-thin sections of infected patchouli leaves. The purified capsid protein has a relative mass of 43 kDa. Polyclonal antibodies were raised in rabbits against the coat protein separated on SDS - PAGE; which were used in ELISA and western blotting. Using specific antibodies in ELISA, PaYMV was frequently detected at patchouli plantations at Lucknow and Bengaluru. Potyvirus-specific degenerate primer pair (U335 and D335) had consistently amplified partial CP gene from crude preparations of infected tissues by reverse transcription polymerase chain reaction (RT-PCR). Comparison of the PCR product sequence (290 bp) with the corresponding regions of established potyviruses showed 78-82% and 91-95% sequence similarity at the nucleotide and amino acid levels, respectively. The results clearly established that the virus under study has close homology with watermelon mosaic virus (WMV) in the coat protein region and therefore could share a common ancestor family. Further studies are required to authenticate the identity of PaYMV as a distinct virus or as an isolate of WMV.