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Abiotic stresses like drought, salinity, heavy metals, and high or low temperature are major constraints to crop production by being detrimental to the physical, metabolic, and growth development of plants [1]. Plants are often subjected to multiple stresses which are aggravated by climatic changes, use of chemical fertilizers, pesticides and environmental pollution. This situation is more alarming with the increase in world population which is expected to reach around 10 billion by 2050 [2]. There is an urgent need to increase food production by 70% to meet the demand [2]. It is also imperative to find ways to implement new agricultural strategies to protect crops from these multiple abiotic stressors [3].Currently, there are several approaches that enhance plant tolerance to abiotic stress. These include waterconserving irrigation strategies, traditional methods of breeding, and genetic engineering of transgenic plants with abiotic stress tolerance [4]. Plant growth-promoting rhizosphere microorganisms are also now being widely used for restoring soil fertility, remediation of chemical pollutants and to sustain plant growth [5]. They are a proven, effective alternative to conventional methods and a promising strategy for mitigating abiotic stresses. The use of plant growth-promoting microorganisms is a simple alternative approach to genetic engineering and breeding methods for crop improvement since these procedures are time-consuming, expensive, and laborious [6]. These microorganisms improve the root and shoot growth, thus enhancing the water and nutrient absorption from soil [7]. Different types of plant metabolites, such as HCN, 2,4-diacetylphloroglucinol (DAPG) [8], antibiotics, e.g., phenazine [9], and volatile compounds [10] help to enhance plant growth [11][12][13]. Exopolysaccharides, are produced by an array of microorganisms like bacteria, cyanobacteria, microalgae, yeasts, and fungi [14]. These exopolysaccharides impart defense against a wide range of environmental stresses like drought [15], metals [16], salt [17], and temperature [18]. Additionally, EPS facilitate microbe-microbe and microbe-plant interaction, provide antioxidants, store carbon, and supply nutrients to support plant growth [6,19]. Diverse bacterial species like Pseudomonas aeruginosa, Azotobacter vinelandii, Sphingomonas paucimobilis, Azotobacter, Paenibacillus, Klebsiella, Bacillus, and Pseudomonas spp. produce EPS and play an important role in sustaining plant growth in abiotic stress environments [20]. The root microbiome, specifically rhizospheric microbes produce phytohormones, 1-aminociclopropane-1-carboxylase (ACC) deaminase, and EPS to sustain Various abiotic stressors like drought, salinity, temperature, and heavy metals are major environmental stresses that affect agricultural productivity and crop yields all over the world. Continuous changes in climatic conditions put selective pressure on the microbial ecosystem to produce exopolysaccharides. Apart from soil aggregation, exopolysaccharide (EPS) production also helps i...

Cancer is among the leading causes of morbidity and mortality worldwide. Current therapy available for cancer treatment is associated with number of side effects. However, plants offer an alternative route for the treatment of cancer. In fact Traditional Knowledge of using herbs and spices for medicinal purposes provide promising new leads that could be utilized for developing new therapies for cancer treatment. The therapeutic properties of spices is due to bioactive components such as alkaloids, terpenes, flavonoids, phenylpropanoids and anthocyanins present in them. Many of these spice derived secondary metabolites have the ability to trigger free radical scavenging pathway at cellular level and thus protect from various metabolic syndromes. Some of the spice based active constituents which are widely known for their chemopreventive action against various malignancies are curcumin and curcuminoids (turmeric), limonene (cardamom), allicin, allyl isothiocyanate (garlic), cinnamic aldehyde, 2-hydroxycinnamaldehyde and eugenol (cinnamon), gingerol, zingiberone, zingiberene (ginger), dipropyle disulfides and quercetin (onion), piperidine piperine, (black pepper), crocetin, crocin and safranal (saffron). These therapeutic agents arrest the activity of cytochrome P450 and isozymes CYP 1A1, cyclooxygenase-2, reducing the activator of transcription-3 (STAT-3) and signal transducer. In addition to this they also down regulate expression of cell cycle protein which in activate caspases killer and suppress Kappa-B activation. Spices also act serve as immunomodulators and regulate inflammatory disorders. The present review highlights the role of common spices in combating cancer.

Drought is a global water shortage problem which poses challenge to crop productivity. Novel strategies are being tried to find out solution to sustain agriculture under drought conditions. Rhizobacteriome is an exclusive genetic material of bacteria resident to rhizosphere plays critical role to health and yield of plant. The interaction of rhizobacteriome with plant provides basis for protecting plants from various abiotic and biotic stresses. Plant growth promoting rhizobacteria (PGPR) are root-colonizing bacteria which produce array of enzymes and metabolites that assist plants to withstand harsh environmental conditions. Various formulations of rhizobacteria are being applied to enhance the tolerance or endurance to drought in crops which in turn increase crop productivity. This could be a one of the promising methods with wide potentiality to improve the growth and yield of crops under limited water resources and changing climatic conditions to ensure food security of the globe. In this review, we summarize (1) existing knowledge and understanding about the rhizobacteria, (2) their role in imparting tolerance to crops in drought conditions and (3) discuss future line of work in this frontier research area.