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The development of novel ornamental variants through targeted mutagenesis represents a key advancement for the aquatic plant industry. However, efficient methods remain limited for generating stable dwarf cultivars in non-model species. This study induced stable dwarf mutants of Cryptocoryne crispatula var. albida through gamma irradiation, focusing on protocol optimization, phenotypic evaluation, and genetic validation. In vitro plantlets were cultured on Murashige and Skoog medium supplemented with 2.0 mg L^- 1 6-benzyladenine, 0.5 mg L^- 1 α-naphthaleneacetic acid, and 100 mg L^- 1 ceftriaxone prior to gamma irradiation using a Cesium-137 source. Linear regression across two independent trials yielded consistent LD₅₀ values of 15.38 and 14.5 Gy, guiding mutagenesis within the 10-16 Gy range. Morphological assessment over three clonal generations identified 10-12 Gy as optimal, producing stable dwarf phenotypes with significantly increased shoot proliferation using 10 Gy and 12 Gy (4.46 ± 0.27 and 5.37 ± 0.47 shoots per plantlet, respectively) compared to controls (3.38 ± 0.60). Leaf length was significantly reduced at 10-12 Gy, whereas leaf width showed a significant reduction only at 10 Gy (p < 0.05). Microscopy confirmed epidermal changes, including reduced adaxial stomatal density from 86 ± 31.5 to 56 ± 20.9 stomata mm^-² and altered guard cell morphology. SCoT26 amplified a unique 1,100 bp fragment in 10-12 Gy mutants, indicating its potential utility as a putative marker for genotypic selection. These findings confirmed that gamma irradiation could effectively generate compact, genetically stable cultivars for C. crispatula var. albida for the Thai aquatic ornamental plant industry.

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.

In Malpighiaceae species, the corolla consists of five petals, with the posterior petal, or flag petal, being distinct in shape and size. This differentiation facilitates the proper orientation and positioning of pollinators, allowing them to access floral oils while simultaneously contacting the anthers and the stigma, thereby enabling pollen transfer. To better understand the role of the corolla in pollinator attraction, a study was conducted on the morphology, anatomy and ultrastructure of all petals of Alicia anisopetala and Callaeum psilophyllum. Flowers at anthesis were collected and fixed for subsequent analysis. Light microscopy, scanning electron microscopy and transmission electron microscopy techniques were employed. The results revealed morphological and anatomical differences between the posterior and lateral petals of both species. Hairs, druse crystals, and fimbriae were identified along the petal margins. Ultrastructural analysis revealed metabolically active and secretory epidermal cells, associated to scent secretion, with distinctive characteristics observed in the emergent structures of the posterior petal of C. psilophyllum. In summary, this study provides detailed information on petal structure in these Malpighiaceae species, suggesting adaptations for pollinator attraction through specific morphological features and fragrance secretion. These findings contribute to a deeper understanding of the fundamental role of the corolla in the pollination of A. anisopetala and C. psilophyllum.

The generalized response of the cyanobacterium Nostoc sp. PCC 7120 to and its recovery from phosphorus (P) starvation stress differ drastically under diazotrophic and non-diazotrophic growth modes. In nitrogen (N) -replete medium, Nostoc sp. PCC 7120 cells were resilient even to prolonged P starvation when its growth was supported by mobilization of cellular reserves of P (polyphosphate) and glycogen on the background of accumulation of nitrogen and carbon reserves (mainly cyanophycin). The P-starving cells quickly recovered upon re-feeding with inorganic phosphate (P_i). Under diazotrophic conditions, P starvation essentially diminished the fixation of dinitrogen. As a result, most of the vegetative cells comprising the trichomes of the cyanobacterium died and decomposed while other cells retained their structural integrity but did not divide. In turn, the latter fell into two categories: some of them showed signs of nutrient starvation; while the other became dormant but did not display the signs of starvation. They resembled neither akinete nor chlorotic cells but were similar to arthrospores lacking a thickened sheath. Re-feeding with P_i triggered a quick resuscitation of the dormant vegetative cells manifested by mobilization of their internal reserves, resumption of the cell growth and division. These processes took place faster than the formation of heterocytes with well-developed envelope (thus, nitrogenase activity recovered by the 7th day after re-feeding of the cells with P_i). The results provide a deeper insight into the mechanisms of stress tolerance in Nostoc sp. PCC 7120 and modulation of the cyanobacterial productivity in natural ecosystems and artificial cultivation facilities by nitrogen and P availability.

Sorghum (Sorghum bicolor L.) is a prominent cereal known for its high photosynthetic efficiency and biomass production, serving as a source of food, animal feed, fiber, and biofuels. This study aims to validate identified meta-genes associated with drought stress in sorghum. Two cultivars, Mansour (drought-tolerant) and Pegah (drought-susceptible), were subjected to drought stress at four levels (25%, 50%, 75%, and 100% of field capacity [FC]( During the 4-5 leaf stage in a greenhouse in 2021. The physiological and molecular responses of the sorghum samples were evaluated at 24, 48, 72, and 96 h post-treatment. The expression of five meta-genes was analyzed to validate these candidate genes related to drought stress tolerance in sorghum. Analysis of variance indicated that the main effects of drought, cultivar, and sampling time, as well as their interactions, had highly significant effects (P < 0.01) on most physiological and biochemical traits. The relative expression of the genes SORBI_3002G225100, SORBI_3003G332200, SORBI_3003G368300, SORBI_3010G081800, and SORBI_3004G293500 increased over time under drought stress. Proline levels, ion leakage, soluble sugars, and the activities of catalase, peroxidase, ascorbate peroxidase, and superoxide dismutase enzymes increased with the intensity of drought stress and over time. Conversely, the levels of chlorophyll a and b, carotenoids, RWC, leaf surface area, and protein content decreased under drought conditions. These results confirm the relevance of these genes in conferring drought stress tolerance in sorghum. This research provides new finding into the physiological processes and biochemical activities, alongside the validation of meta-gene expression involved in drought stress, further advancing our understanding of molecular mechanisms of the reaction of sorghum to drought stress.

Plants depend on nitrogen (N) to support their growth, development, and essential metabolic activities. However, the mechanisms modulating the distribution of N assimilates under supplemental N (SN) condition is unknown. This study examines carbon (C) metabolism and spatial distribution in maize seedlings subjected to three N treatments (T1 to T3): T1, 1 mM NO₃⁻ (low N, LN); T2, supplementation of 1 mM NO₃⁻ with 2 mM NO₃⁻ (1 mM NO₃⁻ → 2 mM NO₃⁻, SN); and T3, 2 mM NO₃⁻ (medium N, MN). SN treatment induced significant physiological and molecular adaptations, such as enhanced growth and total biomass under fluctuating N conditions. SN-treated plants exhibited enhanced photosynthetic activity and significantly greater accumulation of soluble sugars, sucrose, and starch compared to those under LN and MN treatments. Activities of key C metabolism enzymes, such as sucrose phosphate synthase (SPS), sucrose synthase (SuSy) and invertases (INVs), starch synthase (SS), AGPase, α-amylase (AMY) and β-amylase (BAM) were significantly upregulated, supporting efficient C metabolism. Molecular analysis revealed transcriptional reprogramming under SN, marked by the upregulation of genes related to sucrose (ZmSPS1, ZmSuSy1, ZmINVs, ZmSUT2, ZmSTP2, ZmSUC2 and ZmSWEET14) and starch (ZmSS1, ZmAGPase1, ZmAMY1 and ZmBAM1) metabolism and transport. The spatial and diurnal analysis revealed dynamic C partitioning and adaptive regulation, with SN plants maintaining higher sucrose and starch levels in the leaves, sheath and roots. These findings highlight the robust plasticity of maize C metabolism under SN conditions and provide valuable insights into optimizing nitrogen use efficiency (NUE) for sustainable crop production. Future studies will focus on exploring these adaptive mechanisms across different maize genotypes and under field conditions to improve NUE and productivity in varying N environments.

Onopordum acanthium L. (Asteraceae), a traditionally used medicinal plant, was investigated for its morphological, phytochemical, and biological properties in this comprehensive study. Methanolic and aqueous extracts were prepared from different parts of the plant (root, stem, leaf, flower, and fruit) and analyzed for their phenolic composition, antioxidant, antidiabetic, anticholinesterase, antimicrobial, and genotoxic activities. LC-MS/MS analysis revealed that chlorogenic acid was most abundant in the flower (3045.38 ng/mL) and root (728.53 ng/mL) aqueous extracts, while quinic acid reached 856.27 ng/mL in the root. Quercetin, apigenin, and luteolin were also detected at significant levels. The fruit methanol extract showed the highest total phenolic (100.78 ± 0.0015 µg GAE/mg), flavonoid (603.67 ± 0.0015 µg RE/mg), and tannin (186.22 ± 0.0015 µg TAE/mg) contents. Antioxidant assays demonstrated notable ABTS^•⁺ (38.38 ± 0.0042%) and DPPH^• (28.43 ± 0.0252%) scavenging capacities in the same extract. Regarding enzyme inhibition, the flower aqueous extract showed the strongest α-glucosidase inhibition (45.58%), while the fruit aqueous extract exhibited moderate α-amylase inhibition (26.33%). The stem methanol extract displayed the highest acetylcholinesterase inhibition (19.02%), whereas the root aqueous extract showed the highest butyrylcholinesterase inhibition (10.76%). Antimicrobial assays revealed moderate antifungal activity, particularly against Candida tropicalis (MIC = 312.5 µg/mL), with the flower and fruit methanol extracts being the most effective. Genotoxicity assessment using Ames and Allium tests confirmed biosafety up to 5 mg/plate and 250 mg/L, respectively, except for flower extracts, which showed slight cytogenotoxicity. Overall, this study highlights O. acanthium as a promising natural source of phenolic compounds with therapeutic potential, particularly in managing oxidative stress, diabetes, and neurodegenerative disorders.

Drought stress severely impacts mung bean [Vigna radiata (L.) R. Wilczek] production, making exploration of drought tolerance and breeding strategies critical. This study investigated drought resistance mechanisms in ten mung bean cultivars under polyethylene glycol (PEG 6000)-induced water deficit, analyzing germination, morphology, and physiology. Drought impaired vigor index (VI) and seedling growth across all cultivars, with mung bean Bing 20 exhibiting reduced VI (76.28%) and seedling length (63.47%). Drought induced hydrogen peroxide (H₂O₂) bursts, exacerbating membrane lipid peroxidation and elevating malondialdehyde levels, wherein increased H₂O₂ content in Bing 18 (2.02-fold) and elevated malondialdehyde content in Bing 17 (36.64%). Mung bean activated superoxide dismutase, peroxidase, and catalase antioxidant enzymes to mitigate oxidative damage and enhanced seed vigor by upregulating amylase and osmolyte accumulation (soluble sugar, starch, soluble protein, and proline); α-amylase activity in Jin 8 was elevated by 1.68-fold, while Jin 1 exhibited increased starch (1.57-fold) and proline content (40.28-fold). Based on drought resistance coefficients derived from these traits, correlation and principal component analyses (PCA) were performed. Mung bean Jin 1, Jin 7, Jin 8, Bing 11, and Bing 18 were identified as relatively tolerant, whereas Bing 16, Bing 17, Bing 19, Bing 20, and Bing 21 exhibited greater susceptibility. Correlation analysis revealed contrasting metabolic strategies tolerant varieties prioritized rapid early growth, while susceptible varieties showed a complex balance of growth, defense, and osmotic adjustment. PCA identified germination index and seedling length as key drought resistance screening traits. These findings enhance understanding of drought tolerance and facilitate selection of varieties. HIGHLIGHTS: Drought tolerance of ten mung bean cultivars was comprehensively evaluated based on germination, morphological, and physiological profiles under PEG-induced stress. Distinct drought response strategies were revealed between tolerant (prioritizing rapid early growth) and susceptible (balancing growth, defense, and osmotic adjustment) mung bean varieties. Germination index and seedling length were identified as key indicators for screening drought-tolerant mung bean varieties.