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Creating eco-friendly flame retardants (FRs) that are highly effective for textiles while requiring minimal quantities is crucial for both human well-being and environmental conservation. Traditionally, halogen FRs have been the mainstay in this field. Yet, due to their harmful impacts on both human health and the environment, there is a growing demand to discontinue their use. Herein, in this work, a novel eco-friendly intumescent-based flame retardant for cotton fabrics, consisting of ammonium polyphosphate (APP), single-walled carbon nanohorns (SWCNHs), and melamine (MEL) was explored. The addition of SWCNHs demonstrated a clear synergistic effect with APP and MEL in enhancing the flame retardancy of cotton fabrics. After four spraying cycles, the treated cotton fabric ASM4 demonstrated outstanding flame retardancy and self-extinguishing properties. Additionally, its LOI value could reach 24.1 ± 0.1% and the damage length dropped to 4.6 ± 0.2% cm from 30.0 ± 0.1% cm for the pristine cotton fabric, while preserving its original morphology with partial carbonization. The pHRR and THR of ASM4 were dramatically decreased by 90% and 51%, respectively in the cone calorimeter test. Moreover, investigating the thermal degradation kinetics of treated cotton fabric and the physicochemical properties of the char residues revealed the crucial influence of SWCNHs on improving the flame resistance of cotton fabrics. The incorporation of SWCNHs improved both the thermal stability and the degree of graphitization of the char layer, which served as a protective barrier. This barrier efficiently blocked the release of volatile combustible substances while allowing for the emission of nonflammable gases. This work provides a theoretical basis for the feasible application of SWCNHs in intumescent FRs. [ABSTRACT FROM AUTHOR]

SUMMARY: The jasmonic acid (JA) signaling pathway is involved in the plant response to drought stress. JA and other hormones synergistically regulate the drought response in plants. However, the molecular mechanism underlying this synergism remains poorly defined. In the present study, transcriptome analyses of guard cells and quantitative PCR experiments revealed that MYC2 negatively regulated the negative regulator of ABA signaling, SlPP2C1, and the type‐B response regulator in the cytokinin pathway, SlRR26, and this negative regulation was direct. SlRR26 overexpression reduced drought tolerance in transgenic tomatoes, whereas slrr26cr lines were more tolerant to drought. SlRR26 negatively modulated reactive oxygen species levels in stomata and stomatal closure through RobhB. Moreover, SlRR26 overexpression counteracted JA‐mediated stomatal closure, suggesting that SlRR26 played a negative role in the JA‐mediated drought response. These findings suggest that MYC2 plays a key role in JA‐regulated stomatal closure under drought stress by inhibiting SlPP2C1 and SlRR26. [ABSTRACT FROM AUTHOR]

SUMMARY: Cucurbit phloem is complex, with large sieve tubes on both sides of the xylem (bicollateral phloem), and extrafascicular elements that form an intricate web linking the rest of the vasculature. Little is known of the physical interconnections between these networks or their functional specialization, largely because the extrafascicular phloem strands branch and turn at irregular angles. Here, export in the phloem from specific regions of the lamina of cucumber (Cucumis sativus L.) was mapped using carboxyfluorescein and 14C as mobile tracers. We also mapped vascular architecture by conventional microscopy and X‐ray computed tomography using optimized whole‐tissue staining procedures. Differential gene expression in the internal (IP) and external phloem (EP) was analyzed by laser‐capture microdissection followed by RNA‐sequencing. The vascular bundles of the lamina form a nexus at the petiole junction, emerging in a predictable pattern, each bundle conducting photoassimilate from a specific region of the blade. The vascular bundles of the stem interconnect at the node, facilitating lateral transport around the stem. Elements of the extrafascicular phloem traverse the stem and petiole obliquely, joining the IP and EP of adjacent bundles. Using pairwise comparisons and weighted gene coexpression network analysis, we found differences in gene expression patterns between the petiole and stem and between IP and EP, and we identified hub genes of tissue‐specific modules. Genes related to transport were expressed primarily in the EP while those involved in cell differentiation and development as well as amino acid transport and metabolism were expressed mainly in the IP. Significance Statement: Members of the Cucurbitaceae have complex, and in some regards unique, phloem with strands on both sides of the xylem and an elaborate interconnecting phloem network. Here we trace food transport routes from leaves to shoots of cucumber plants with fluorescent and radiolabeled tracers and X‐ray computed tomography. We also analyze gene expression networks in the internal and external phloem employing laser‐capture microdissection followed by the RNA deep sequencing approach. [ABSTRACT FROM AUTHOR]

Background: Guard cell protoplasts (GCPs) isolated from various plants have proven to be especially useful for studies of signal transduction pathways and plant development. But it is not easy to isolate highly purified preparations of large numbers of GCPs from plants. In this research, our focus is on a method to isolate large numbers of guard cells from tomato leaves. The protocols described yield millions of highly purified, viable GCPs, which are also suitable for studies on guard cell physiology. Results: We developed an efficient method for isolating GCPs from epidermal fragments of tomato leaves. The protocol requires a two-step digestion to isolate high-quality tomato GCPs. In this procedure, cellulysin (in method L) was replaced by cellulose “Onozuka” RS (in method S) in the first digestion step, which indicated that cellulase RS was more effective than cellulysin. Method S dramatically shortened the time required for obtaining high yields and high-quality GCPs. Moreover, according to the GCP yields, hydroponic plants were more effective than substrate-cultured plants. Conclusions: In this paper, protocols for large-scale preparation of GCPs and mesophyll cell protoplasts were described, followed by some success examples of their use in biochemical and molecular approaches such as reverse-transcription polymerase chain reaction, real-time polymerase chain reaction and sodium dodecyl sulfate–polyacrylamide gel electrophoresis. The method was proved to be a more efficient GCP-isolating method, capable of providing high yields with better quality in less time. [ABSTRACT FROM AUTHOR]