Being sessile organisms, plants are often exposed to a wide array of abiotic and biotic stresses. Abiotic stress conditions include drought, heat, cold and salinity, whereas biotic stress arises ...mainly from bacteria, fungi, viruses, nematodes and insects. To adapt to such adverse situations, plants have evolved well-developed mechanisms that help to perceive the stress signal and enable optimal growth response. Phytohormones play critical roles in helping the plants to adapt to adverse environmental conditions. The elaborate hormone signaling networks and their ability to crosstalk make them ideal candidates for mediating defense responses.
Recent research findings have helped to clarify the elaborate signaling networks and the sophisticated crosstalk occurring among the different hormone signaling pathways. In this review, we summarize the roles of the major plant hormones in regulating abiotic and biotic stress responses with special focus on the significance of crosstalk between different hormones in generating a sophisticated and efficient stress response. We divided the discussion into the roles of ABA, salicylic acid, jasmonates and ethylene separately at the start of the review. Subsequently, we have discussed the crosstalk among them, followed by crosstalk with growth promoting hormones (gibberellins, auxins and cytokinins). These have been illustrated with examples drawn from selected abiotic and biotic stress responses. The discussion on seed dormancy and germination serves to illustrate the fine balance that can be enforced by the two key hormones ABA and GA in regulating plant responses to environmental signals.
The intricate web of crosstalk among the often redundant multitudes of signaling intermediates is just beginning to be understood. Future research employing genome-scale systems biology approaches to solve problems of such magnitude will undoubtedly lead to a better understanding of plant development. Therefore, discovering additional crosstalk mechanisms among various hormones in coordinating growth under stress will be an important theme in the field of abiotic stress research. Such efforts will help to reveal important points of genetic control that can be useful to engineer stress tolerant crops.
Overall growth and development of a plant is regulated by complex interactions among various hormones, which is critical at different developmental stages. Some of the key aspects of plant growth ...include seed development, germination and plant survival under unfavorable conditions. Two of the key phytohormones regulating the associated physiological processes are gibberellins (GA) and abscisic acid (ABA). GAs participate in numerous developmental processes, including, seed development and seed germination, seedling growth, root proliferation, determination of leaf size and shape, flower induction and development, pollination and fruit expansion. Despite the association with abiotic stresses, ABA is essential for normal plant growth and development. It plays a critical role in different abiotic stresses by regulating various downstream ABA-dependent stress responses. Plants maintain a balance between GA and ABA levels constantly throughout the developmental processes at different tissues and organs, including under unfavorable environmental or physiological conditions. Here, we will review the literature on how GA and ABA control different stages of plant development, with focus on seed germination and selected abiotic stresses. The possible crosstalk of ABA and GA in specific events of the above processes will also be discussed, with emphasis on downstream stress signaling components, kinases and transcription factors (TFs). The importance of several key ABA and GA signaling intermediates will be illustrated. The knowledge gained from such studies will also help to establish a solid foundation to develop future crop improvement strategies.
We explain how the invariant subspace method can be extended to a scalar and coupled system of time-space fractional partial differential equations. The effectiveness and applicability of the method ...have been illustrated using time-space (i) fractional diffusion-convection equation, (ii) fractional reaction-diffusion equation, (iii) fractional diffusion equation with source term, (iv) two-coupled system of fractional diffusion equation, (v) two-coupled system of fractional stationary transonic plane-parallel gas flow equation and (vi) three-coupled system of fractional Hirota–Satsuma KdV equation. Also, we explicitly showed how to derive more than one exact solution of the equations as mentioned above using the invariant subspace method.
This letter presents an enhanced hybrid switchedcapacitor-based buck power factor correction (HSC-BPFC) rectifier suited for high-efficiency applications. The suggested PWM strategy results in a ...five-level voltage waveform at its input AC terminals. Therefore, a lower volt-second on the input inductor results in a smaller inductor size and lesser current ripple. In addition, compared to equivalent contemporary design, the reduced switching transitions of all devices within a line-frequency cycle result in reduced power losses. Also, the semiconductor devices and energy storage components incur lesser current stress and have decreased conduction losses. Further, the comparative analysis reveals the enhanced performance of the proposed rectifier. The practicality of the proposed HSC-BPFC rectifier is verified through the experimental results.
In this paper, a systematic study for finding the symmetry group classification is performed for the time-fractional Kudryashov–Sinelshchikov equation, which describes the pressure waves in liquid ...with gas bubbles. Using Lie symmetries, the vector fields, and invariance properties of the underlying equation with various cases are presented and then similarity reductions are obtained. Furthermore, using the new conservation theorem, conservation laws are constructed for all possible cases. Finally, based on the invariant subspace method, a variety of exact solutions are derived using the obtained invariant subspaces, including the trigonometric, exponential, and polynomial type of solutions.
•Green synthesis of silver nanoparticles by the leaf extract of Mimusops elengi, L.•It's well characterized by UV–vis spectroscopy, SEM, FTIR and XRD.•It shows effective antibacterial property ...against multi drug resistant clinical isolates.
Green synthesis of metallic silver nanoparticles has attracted nowadays and alternative to physical and chemical approaches. In the present study, silver nanoparticles (AgNPs) were synthesized from leaf extract of Mimusops elengi, L. at room temperature. Formation of stable AgNPs at 1mM concentrations of silver nitrate (AgNO3) typically gave spherical shape particles with diameter range from 55 to 83nm. The kinetic properties of particle formation were proportional to the effect of concentration of AgNO3 solution. In order to identify the compounds responsible for the bioreduction of Ag+ ion and the stabilization of AgNPs produced, the functional group present in Mimusops elengi, L. leaf extract was investigated using FTIR. The formation of nanoparticle was confirmed using the surface plasmon resonance band shown in UV–vis spectrophotometer. The topography and morphology of the particles were determined using scanning electron microscopy. The crystalline nature of nanoparticles was confirmed from the XRD pattern. Furthermore these green synthesized AgNPs were found to show higher antimicrobial efficacy against multi drug resistant clinical isolates.
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In this paper, we explain how to construct a complete classification of invariant subspaces for the generalized nonlinear convection-reaction-diffusion equation. Also, we have explicitly shown that ...the convection-reaction-diffusion equation admits more than one invariant subspaces in different dimensions which in turn helps to derive more than one different types of exact solution.
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