Biofilm producing plant growth promoting bacteria in combination with glycine betaine uplift drought stress tolerance of maize plant.

Introduction: The escalating threat of drought poses a significant challenge to sustainable food production and human health, as water scarcity adversely impacts various aspects of plant physiology. Maize, a cornerstone in staple cereal crops, faces the formidable challenge of drought stress that triggers a series of transformative responses in the plant. Methods: The present study was carried out in two sets of experiments. In first experiment, drought stress was applied after maintaining growth for 45 days and then irrigation was skipped, and plant samples were collected at 1st, 3rd and 6th day of drought interval for evaluation of changes in plant growth, water relation (relative water content) and antioxidants activity by inoculating indigenously isolated drought tolerant biofilm producing rhizobacterial isolates (Bacillus subtilis SRJ4, Curtobacterium citreum MJ1). In the second experiment, glycine betaine was applied as osmoregulator in addition to drought tolerant PGPR to perceive modulation in photosynthetic pigments (Chlorophyll a and b) and plant growth under varying moisture stress levels (100, 75 and 50% FC). Results and discussion: Results of the study revealed upsurge in root and shoot length, fresh and dry biomass of root and shoot besides increasing chlorophyll contents in water stressed inoculated plants compared to uninoculated plants. Glycine betaine application resulted in an additional boost to plant growth and photosynthetic pigments, when applied in combination with bacterial inoculants. However, both bacterial inoculants behaved differently under drought stress as evident from their biochemical and physiological attributes. Isolate SRJ4 proved to be superior for its potential to express antioxidant activity, leaf water potential and relative water contents and drought responsive gene expression while isolate MJ1 showed exclusive increase in root dry biomass and plant P contents. Though it is quite difficult to isolate the bacterial isolates having both plant growth promoting traits and drought tolerance together yet, such biological resources could be an exceptional option to be applied for improving crop productivity and sustainable agriculture under abiotic stresses. By exploring the combined application of PGPR and glycine betaine, the study seeks to provide insights into potential strategies for developing sustainable agricultural practices aimed at improving crop resilience under challenging environmental conditions.

Signaling Green: Impact of Green Product Attributes on Consumers Trust and the Mediating Role of Green Marketing.

The purpose of this research is to highlight the relationship between green product attributes and consumer trust that influence consumers' decision to purchase green products in the context of Pakistan. This study contributes to determining quantitatively how green product attributes such as physical, perceptual, and reflexive attributes influence consumers' trust to purchase a green product and investigates the mediating role of green marketing. Data was collected from different industrial sectors through a survey questionnaire. We employed Structural Equation Modeling (SEM) using the SMART-PLS software to check the reliability and validity of the constructs, and to test the hypotheses. This study reveals variations in terms of shaping the sustainable consumers' buying behavior by modifying product attributes and green marketing strategies that are in congruence with the proposed hypotheses of this study. In the end, the findings and interpretations of the results are given which can guide the managers to develop effective green marketing campaigns in reshaping the purchase intentions of consumers toward their green products.

Engineering tolerance to CLCuD in transgenic Gossypium hirsutum cv. HS6 expressing Cotton leaf curl Multan virus-C4 intron hairpin.

Cotton leaf curl disease (CLCuD), caused by begomoviruses in combination with betasatellite molecule, has adversely affected cotton industry of Indian subcontinent. To devise a CLCuD-control strategy, RNAi-mediated approach was followed in this study. Gossypium hirsutum cv. HS6 plants were transformed with intron-hairpin RNAi (ihpRNAi-C4) construct carrying silencing suppressor C4 gene of Cotton leaf curl Multan virus (CLCuMuV). Efficacy of the construct in imparting CLCuD resistance was evaluated in transgenic (T0, T1) cotton lines. Accumulation of CLCuMuV/betasatellite and attenuation of CLCuD symptoms in the transgenic lines were monitored at different times interval after virus inoculation. Northern hybridization revealed the expression of C4-gene derived siRNA. Expression of the ihpRNAi transcript was recorded higher in transgenic lines expressing siRNA which supposedly targeted the C4 gene. A significant delay in detection of virus as well as betasatellite was observed in the transgenic lines. At 30 days post inoculation (dpi), none of the lines tested positive. At 45 dpi, however, it could be detected in few lines having much lower titre as compared to non-transformed control plants. Notably, till 60 dpi, no significant progression of the virus/betasatellite DNA was observed and the plants did not exhibit any characteristic CLCuD symptoms. A tolerance phenomenon leading to escape of CLCuD symptoms in the transformed cotton was described.

Harmine, a natural beta-carboline alkaloid, upregulates astroglial glutamate transporter expression.

Glutamate is the predominant excitatory amino acid neurotransmitter in the mammalian central nervous system (CNS). Glutamate transporter EAAT2/GLT-1 is the physiologically dominant astroglial protein that inactivates synaptic glutamate. Previous studies have shown that EAAT2 dysfunction leads to excessive extracellular glutamate and may contribute to various neurological disorders including amyotrophic lateral sclerosis (ALS). The recent discovery of the neuroprotective properties of ceftriaxone, a beta lactam antibiotic, suggested that increasing EAAT2/GLT-1 gene expression might be beneficial in ALS and other neurological/psychiatric disorders by augmenting astrocytic glutamate uptake. Here we report our efforts to develop a new screening assay for identifying compounds that activate EAAT2 gene expression. We generated fetal derived-human immortalized astroglial cells that are stably expressing a firefly luciferase reporter under the control of the human EAAT2 promoter. When screening a library of 1040 FDA approved compounds and natural products, we identified harmine, a naturally occurring beta-carboline alkaloid, as one of the top hits for activating the EAAT2 promoter. We further tested harmine in our in vitro cell culture systems and confirmed its ability to increase EAAT2/GLT1 gene expression and functional glutamate uptake activity. We next tested its efficacy in both wild type animals and in an ALS animal model of disease and demonstrated that harmine effectively increased GLT-1 protein and glutamate transporter activity in vivo. Our studies provide potential novel neurotherapeutics by modulating the activity of glutamate transporters via gene activation. This article is part of a Special Issue entitled 'Trends in neuropharmacology: in memory of Erminio Costa'.