Chitosan-GSNO nanoparticles : a positive modulator of drought stress tolerance in soybean

Funding: This research was supported by Basic Science Research Program through the National Research Foundation (NRF) of Korea funded by the Ministry of Education (RS-2023-00245922) to Prof. Byung-Wook Yun and by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2021R1I1A1A01049154) to Dr. Bong-Gyu Mun.Background : Chitosan biopolymer is an emerging non-toxic and biodegradable plant elicitor or bio-stimulant. Chitosan nanoparticles (CSNPs) have been used for the enhancement of plant growth and development. On the other hand, NO is an important signaling molecule that regulates several aspects of plant physiology under normal and stress conditions. Here we report the synthesis, characterization, and use of chitosan-GSNO nanoparticles for improving drought stress tolerance in soybean. Results: The CSGSNONPs released NO gas for a significantly longer period and at a much lower rate as compared to free GSNO indicating that incorporation of GSNO in CSNPs can protect the NO-donor from rapid decomposition and ensure optimal NO release. CS-GSNONPs improved drought tolerance in soybean plants reflected by a significant increase in plant height, biomass, root length, root volume, root surface area, number of root tips, forks, and nodules. Further analyses indicated significantly lower electrolyte leakage, higher proline content, higher catalase, and ascorbate peroxidase activity, and reduction in MDA and H2O2 contents after treatment with 50 μM CS-GSNONPs under drought stress conditions. Quantitative real-time PCR analysis indicated that CS-GSNONPs protected against drought-induced stress by regulating the expression of drought stress-related marker genes such as GmDREB1a, GmP5CS, GmDEFENSIN, and NO-related genes GmGSNOR1 and GmNOX1. Conclusions : This study highlights the potential of nano-technology-based delivery systems for nitric oxide donors to improve plant growth, and development and protect against stresses.Publisher PDFPeer reviewe

Elucidating the piezoelectric, ferroelectric, and dielectric performance of lead-free KNN/PVDF and its copolymer-based flexible composite films

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Elucidating the Piezoelectric, Ferroelectric, and Dielectric Performance of Lead-Free KNN/PVDF and Its Copolymer-Based Flexible Composite Films

Ecofriendly, reliable, and high-performance piezoelectric materials are drawing huge interest in resolving the environmental problems arising due to consumption of fossil fuel energy. Among the lead-free ferroelectrics, potassium sodium niobate (KNN, (K,Na)NbO3) is one of the most promising piezoelectric ceramics that can replace Pb(Zr,Ti)O3. In the present work, the piezoelectric performance of KNN incorporated in poly(vinylidene fluoride) (PVDF) and its copolymers, polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) and poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP), has been compared. The films were fabricated by a solution casting method and were further polarized by a corona poling technique. The results confirmed that the nanocomposite film with 8 wt % KNN filler in PVDF-TrFE (PTK8) exhibited the highest F(β) value, maximum remnant polarization, and dielectric constant value than other nanocomposites. The relative β-phase contents in PTK8, PHK8, and PK8 composite films reached 85, 76, and 75.8%, respectively, indicating that KNN acts as the most suitable nucleating agent in PVDF-TrFE. Also, the piezoelectric voltage output of the PTK8-based nanogenerator was found to be remarkably higher (∼20 V) as compared to other nanocomposite-based piezoelectric nanogenerators. It also exhibited a maximum power density of 0.54 μW/cm2 that was significantly improved in comparison to other composites. This nanogenerator was found to be a promising power generation device promoting miniaturization of self-powered systems

Additional file 1 of Chitosan-GSNO nanoparticles: a positive modulator of drought stress tolerance in soybean

Additional file 1: Supplementary Figure S1. Characterization of chitosan nanoparticles (CSNPs) and chitosn-GSNO nanoparticles (CS-GSNONPs)