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Sideroxylon obtusifolium (Humb. ex Roem. & Schult.) T.D. Penn. is a tree species belonging to the Sapotaceae family, whose black berries can be consumed fresh or as jam. It is widely distributed in Mexico, Belize, Costa Rica, Venezuela, Bolivia, Brazil, Paraguay, Argentina, and Uruguay. While previous studies have focused on describing its floral biology, the development of the ovule and pollen has not been studied from an anatomical point of view. To provide further insights into the sexuality of this fruit tree, we conducted a study of the processes of sporogenesis and gametogenesis using conventional plant anatomical techniques. Flowers of different sizes were fixed in FAA, embedded in paraffin, sectioned, and stained with Safranin-Astra Blue for light microscopy. The processes of sporogenesis and gametogenesis result, on the one hand, in the anatropous, unitegmic, and tenuinucellate ovule, with a Polygonum embryo sac. On the other hand, it gives pollen grains that are released as monads in a tricellular state. This study provides anatomical data not previously described for this species and is part of the embryological studies that are currently being carried out in different species of fruit trees in South America. These findings enhance the embryological understanding of Sapotaceae and offer a foundation for future research in systematics, phylogeny, and conservation biology of Sapotaceae.

This study examined the influence of exogenous gamma-aminobutyric acid (GABA) on drought tolerance in faba bean (Vicia faba) under 15% PEG-induced drought stress conditions. Faba bean plants were subjected to treatments with varying GABA concentrations (0.5, 1, and 2 mM) to evaluate physiological, biochemical, and molecular responses to drought stress. The results indicated that a concentration of 0.5 mM GABA significantly enhanced the photosynthetic rate, stomatal conductance, and chlorophyll content, while also markedly improving relative water content (RWC). At this concentration, GABA treatment mitigated oxidative damage, evidenced by reduced levels of malondialdehyde (MDA) and hydrogen peroxide (H₂O₂), and increased antioxidant enzyme activities (catalase, superoxide dismutase, and ascorbate peroxidase). Furthermore, GABA supplementation influenced the accumulation of proline and soluble sugars, thereby facilitating osmotic regulation and stress adaptation. Gene expression analysis revealed that GABA modulated key drought-responsive genes, notably enhancing the expression of those associated with antioxidant defenses (VfCAT, VfSOD, VfAPX), water transport (VfPIP), and osmoprotection (VfP5CDH), particularly in leaf and root tissues, with differential effects observed across GABA concentrations. Interestingly, higher concentrations of GABA (1 and 2 mM) yielded reduced or inconsistent outcomes, suggesting the existence of an optimal concentration threshold for stress mitigation. Collectively, these findings underscore the potential of GABA as a beneficial agent for enhancing drought resilience in faba bean, providing a promising strategy to improve crop tolerance to water scarcity.

Cadmium (Cd) pollution has emerged as a critical global environmental concern due to its significant toxicity, environmental persistence, and the pervasiveness of contamination. In recent years, essential oils (EOs) have been recognized as a promising, environmentally friendly substitute for traditional chemical treatments to counteract metal toxicity in plants. Moreover, these naturally derived compounds improve plant resilience when facing challenging environmental conditions. This study explores the potential of EOs extracted from the aerial tissues (flowering shoots and leaves) of the halophyte plant Lobularia maritima to alleviate Cd toxicity in durum wheat exposed for 10 days to 30 µM CdCl₂. GC-MS analysis revealed that L. maritima essential oil (LmEO) was predominantly composed of oxygenated monoterpenes (74.40%). The impact of various LmEO concentrations (2, 4, 6, and 8 ppm) on seed germination and early growth of durum wheat identified 4 ppm as the most effective. Application of LmEO (at 4 ppm) significantly enhanced seedling tolerance to Cd by promoting growth, reducing Cd accumulation in shoots by approximately 41%, and malondialdehyde content (a marker membrane damage) by 43% compared to the Cd-stressed plants. LmEO treatment also reduced oxidative stress by boosting antioxidant enzyme activity and reducing ROS accumulation. Furthermore, RT-qPCR analysis of six genes encoding heavy metal transporters in roots (TdNRAMP, TdHMA5, TdHMT1, TdZIF1, TdZIFL2, and TdZTP29) revealed that several key genes were upregulated by approximately twofold in durum wheat seedlings treated with LmEO, suggesting a potential link to improved Cd tolerance. Our findings suggest that exogenous LmEO application is associated with enhanced Cd stress resilience through reduced metal accumulation and improved antioxidant defense in durum wheat. These results indicate the potential of LmEO as a natural biostimulant to improve crop growth in contaminated soils.

Northeast India, a global biodiversity hotspot, harbors exceptional plant diversity within the Indo-Burma region. This study provides the first comprehensive integration of floristic, ecological, and genomic analyses of angiosperm diversity in North Guwahati, Assam, using the Indian Institute of Technology Guwahati campus as a model semi-natural landscape. Systematic year-long surveys recorded 434 angiosperm species belonging to 312 genera and 101 families, including 70 trees, 86 shrubs, and 244 herbs (with 31 climbers and a few aquatics). Poaceae was the most species-rich family (34 species), followed by Fabaceae (29) and Cyperaceae (26), reflecting typical tropical diversity. Spatial analysis revealed strong habitat-specific species distribution, with open plains supporting the highest diversity (206 species) and forest edges harboring rare taxa. Community structure across four ecological zones showed significant spatial heterogeneity, with Zone 1 having the highest Shannon-Wiener diversity (H' = 4.084) and Zone 4 the highest evenness (E = 0.905). Nuclear DNA content (2C values) was estimated via flow cytometry for 110 species, contributing 58 novel genome size records and revealing a 98-fold variation (0.43-42.5 pg). Monocots had significantly larger genomes than dicots (4.79 vs. 1.63 pg, p < 0.001), and ecological trends showed a progressive increase in genome size from herbaceous (1.93 pg) to woody forms (2.50 pg), supporting the large genome constraint hypothesis. GIS mapping integrated taxonomic, ecological, and genomic data, uncovering spatial patterns in diversity and genome evolution. region. This comprehensive framework provides a crucial foundation for assessing biodiversity and guiding conservation efforts in this ecologically important region.

H₂S is a lipophilic gaseous molecule with the characteristic pungent "rotten egg" odour. Studies have shown that H₂S at lower concentrations acts as a gasotransmitter, providing evidence for its crucial role in plant growth, development and stress responses. The present work underlies the effects of moderate and high concentrations of NaCl stress and two concentrations of NaHS (H₂S donor) on certain metabolic signatures of tomato seedlings. In this study, tomato seedlings were grown under different NaCl concentrations (0 mM, 40 mM, 80 mM and 120 mM) and three concentrations of H₂S, i.e. T0 (0 µM), T1 (25 µM) and T2 (100 µM) were applied exogenously. The results showed a reduction in MDA content, electrolytic leakage, Na⁺/K⁺ ratio, and proline content in tomato seedlings with exogenous application of H₂S under NaCl stress. On the contrary, exogenous H₂S application at T2 concentration increased chlorophyll content, RWC, endogenous H₂S content, L-DES activity and ascorbate content under 80 mM NaCl stress. Concomitantly, exogenous H₂S treatment, particularly at T2 concentration, upregulated the antioxidative enzyme activity like glutathione reductase (GR), catalase (CAT), ascorbate peroxidase (APOD), peroxidase (POD) and superoxide dismutase (SOD) in NaCl-treated tomato seedlings. These results indicate that exogenous H₂S application, especially at T2 concentration, imparts a higher amount of alleviation in salt-stressed tomato seedlings grown under 80 mM NaCl. Thus, a concentration-dependent interaction of NaCl stress and H₂S signaling appears to be mediated through long-distance signaling in tomato seedlings.

The dioecious species Ilex paraguariensis (yerba mate) holds significant economic and cultural value, yet key aspects of its reproductive development remain unresolved. This study combines histological, scanning electron microscopy (SEM), and cytogenetic analyses to elucidate floral ontogeny, microsporogenesis, and sexual differentiation in yerba mate. For both sexes, six arbitrary descriptive stages of floral development were established based on all available data. Our findings reveal that floral development follows a type I pattern, initiating as bisexual before diverging into unisexual flowers. In staminate flowers, functional androecium development coincides with early parenchymatization of the pistillode and suppression of megasporangial initiation-a potential adaptive strategy to minimise resource wastage. Cytogenetic analysis confirmed regular microsporogenesis, identified off-plate bivalents at higher frequencies than previously reported, and provided the first complete meiotic progression leading to gamete formation in this species. Besides, SEM revealed novel stephanocytic structures on pistillodes, interpreted as nectarostomata, suggesting a role in pollinator attraction. These findings challenge prior assumptions regarding nectary presence in yerba mate. In pistillate flowers, staminodes undergo abortion via tapetal degeneration and aberrant sporogenous tissue collapse before meiosis, aligning with previously defined categories of organ abortion. Sexual dimorphism emerges early and is governed by distinct mechanisms: constitutive pistillode sterility in males and selective microsporangial tissue abortion within the antherodes in females. This study advances the understanding of reproductive biology in a commercially important crop, providing key morphological and cytological insights that will guide future taxonomic, developmental, and evolutionary studies within Ilex.

The integrity of herbal products is frequently undermined by both intentional and unintentional adulteration, leading to substantial health risks and economic losses. Loop-mediated isothermal amplification (LAMP), a DNA-based molecular technique, has emerged as a formidable solution due to its simplicity, specificity, sensitivity, and ability to operate under isothermal conditions. The review critically evaluates the application of LAMP in authenticating herbal materials, showcasing its enhanced efficiency and user-friendliness compared to conventional techniques. The LAMP technique employs four to six primers that target six to eight distinct regions of the target DNA, ensuring unparalleled specificity. The amplification at a constant temperature negates the need for thermal cyclers, thus rendering it highly suitable for point-of-care applications and field-based authentication. The article presents case studies that illustrate LAMP's efficacy in detecting adulteration across traditional medicines, dietary supplements, and crude drug materials. Visualization methods in LAMP, such as turbidity, colorimetry, and fluorescence, greatly enhance its accessibility and ease of use, making it well-suited for both laboratory and field applications. Although there are limitations, such as primer design complexity and contamination risks, recent innovations, including the use of lyophilized reagents, multiplexing capabilities, and integration with mobile detection platforms, are significantly advancing the practicality of LAMP assays. This review underscores the potential of LAMP in both regulatory and commercial contexts, promoting the authenticity, safety, and quality of herbal products, thereby making a vital contribution to consumer protection and the sustainability of the herbal medicine trade.

Floral nectaries are generally linked to an exchange that facilitates pollen transport, and consequently, pollination. We have characterized the ontogenesis, histochemistry, and ultrastructure of the floral nectary of Pseudobombax longiflorum (Mart.) A. Robyns (Bombacoideae, Malvaceae) from a developmental perspective and related with secretion dynamics. Light and electron microscopies were used. The floral nectary is on the proximal and median portions of the adaxial face of the calyx. Protoderm, fundamental meristem, and procambial strands form the nectary. At maturity, it is composed of glandular claviform trichomes and nectariferous and subnectariferous parenchyma vascularized predominantly by phloem. Phenolic compounds, oils, and proteins were observed in the trichome and parenchyma cells. Druse crystals occurred in the parenchyma. Starch grains decreased in the parenchyma in pre-anthesis buds, and with the nectar exudation began. Mitochondria, ribosomes, endoplasmic reticulum, Golgi bodies, and plastids containing starch grains characterize the cytoplasm of secretory cells and the apparatus compatible with nectar production. Plamodesmata occurred between parenchyma cells, parenchyma cell and basal trichome cell, and trichome cells, indicating a symplastic pathway of the pre-nectar. The downward flow of nectar through the apoplast could be prevented by the impregnation of lipids into the anticlinal walls of the stalk cell. In trichome apical cell, nectar accumulation occurred in periplasmic and subcuticular spaces. Nectar appeared to be externalized through the cell wall and cuticle. Insights into trichome development have enhanced our understanding of the formation of functional floral nectary components and nectar secretion in Malvaceae, marking the first ontogenetic and ultrastructural study in Bombacoideae.

Calcium is a central signal regulating a plethora of cellular events. Specificity is brought about by spatio-temporal patterns, so-called signatures that are established by the activity of calcium channels residing in the membranes of different compartments. The role of two-pore calcium channels (TPC) for such signatures has been debated controversially, because evidence for localisation in both, the plasma membrane as well as in the tonoplast, has been proposed. Using a GFP fusion of the tobacco homologue NtTPC1A in the background of tobacco BY-2 cells, we show that this channel is localised at the tonoplast. This localisation depends on actin filaments, but not on microtubules, as shown by pharmacological interference. Since the construct is driven by the constitutive Cauliflower Mosaic Virus 35S promoter, we can also detect phenotypic differences, such as impaired auxin-dependent cell elongation, reduced intracellular calcium content (that can be rescued by supplementation of calcium), and partial resistance to gadolinium, inhibitors of calcium influx. We also monitored the response to harpin, an elicitor from the phytopathogenic bacterium Erwinia amylovora. Here, the overexpressor line shows a higher sensitivity indicating that NtTPC1Aparticipates in defence-related programmed cell death. The data are discussed with respect to a role of NtTPC1A for spatial calcium signatures, and the regulation of cell growth by actin and auxin.