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In plants, heteromorphic self-incompatibility (HetSI) is a strategy for avoiding self-pollination and promoting outcrossing, and during this process, numerous protein-protein interaction events occur between the pistil and pollen. Previous studies in Primula and Fagopyrum that focused on HetSI systems have provided interesting insights; however, the molecular mechanism underlying HetSI remains largely unknown. In this study, we profiled the proteome of Plumbago auriculata stigmas before and after self-incompatible (SI) and self-compatible (SC) pollination. Comparative analyses were conducted by 4D-DIA (Four-dimensional data independent acquisition), a promising technology that increases the sensitivity and reduces the spectral complexity of proteomic analysis by adding a fourth dimension, ion mobility. The results revealed 33387 peptides and 5311 proteins in all samples. The pathways in which the differentially expressed proteins (DEPs) identified in the P × P (Pin style self-pollinated with pin pollen) vs. PS (Pin style) and T × T (Thrum style self-pollinated with thrum pollen) vs. TS (Thrum style) comparisons were significantly enriched were biosynthesis of secondary metabolites and pentose and glucuronate interconversions. In the P × T (Pin style cross-pollinated with thrum pollen) vs. PS and T × P (Thrum style cross-pollinated with pin pollen) vs. TS comparison, the top three pathways were biosynthesis of secondary metabolites, pentose and glucuronate interconversions, and phenylpropanoid biosynthesis. The phenylpropanoid biosynthesis, cutin, suberine and wax biosynthesis, and flavonoid biosynthesis pathways were enriched in the P × T vs. P × P comparison, and starch and sucrose metabolism, glycerophospholipid metabolism, and alpha-linolenic acid metabolism were abundant in the T × T vs. T × P comparison. The enriched pathways between PS and TS were the biosynthesis of secondary metabolites, phenylpropanoid biosynthesis, and pentose and glucuronate interconversion. Self-incompatibility protein S1 (SI S1), Mitogen-activated protein kinase 3/4 (MPK3/4), Mitogen-activated protein kinase kinase 2/3 (M2K2/3), Exocyst complex component EXO70A1 (E70A1) and Thioredoxin H1/2 (TRXH1/2) were found to be HetSI-related candidates, and O-fucosyltransferase 23 (OFT23), 3- ketoacyl-CoA synthase 6 (KCS6), Receptor-like protein kinase FERONIA (FERON), Fimbrin-5 (FIMB5), Pollen-specific leucine-rich repeat extensin-like protein 4 (PLRX4), Transcription initiation factor IIB-2 (TF2B2) and Pectinesterase 1 (AL11A), etc., were identified as other regulatory transducers. These findings combined with our morphological and reactive oxygen species (ROS) intensity analyses indicate that P. auriculata has typical dry-stigmas and that the HetSI mechanism might differ between the pin and thrum. SI S1 might be the key factor in HetSI, and ROS are overexpressed during SC pollination to rapidly activate the mitogen-activated protein kinase (MAPK)-mediated phosphorylation of E70A1 to maintain stigma receptivity in plants with HetSI. [ABSTRACT FROM AUTHOR]

Chagas disease (CD) caused by the protozoan Trypanosoma cruzi affects more than six million people worldwide. Treatment is restricted to benznidazole (Bz) and nifurtimox (Nf) that display low activity in the later chronic stage besides triggering toxic events that result in treatment abandonment. Therefore, new therapeutic options are necessary. In this scenario, natural products emerge as promising alternatives to treat CD. In the family Plumbaginaceae, Plumbago sp. exhibits a broad spectrum of biological and pharmacological activities. Thus, our main objective was to evaluate, in vitro and in silico, the biological effect of crude extracts of root and of aerial parts of P. auriculata, as well as its naphthoquinone Plumbagin (Pb) against T. cruzi. The phenotypic assays revealed potent activity of the root extract against different forms (trypomastigote and intracellular forms) and strains (Y and Tulahuen), with a compound concentration that reduced 50% of the number of the parasite (EC50) values ranging from 1.9 to 3.9 µg/mL. In silico analysis showed that Pb is predicted to have good oral absorption and permeability in Caco2 cells, besides excellent probability of absorption by human intestinal cells, without toxic or mutagenic potential effects, not being predicted as a substrate or inhibitor of P-glycoprotein. Pb was as potent as Bz against intracellular forms and displayed a superior trypanosomicidal effect (about 10-fold) in bloodstream forms (EC50 = 0.8 µM) as compared to the reference drug (8.5 µM). The cellular targets of Pb on T. cruzi were evaluated using electron microscopy assays and the findings on bloodstream trypomastigotes showed several cellular insults related to the autophagic process. Regarding toxicity in mammalian cells, the root extracts and the naphthoquinone present a moderate toxic profile on fibroblasts and cardiac cell lines. Then, aiming to reduce host toxicity, the root extract and Pb were tested in combination with Bz, and the data showed additive profiles with the sum of the fractional inhibitory concentration indexes (ΣFICIs) being 1.45 and 0.87, respectively. Thus, our work reveals the promising antiparasitic activity of Plumbago auriculata crude extracts and its purified naphthoquinone Plumbagin against different forms and strains of Trypanosoma cruzi in vitro. [ABSTRACT FROM AUTHOR]

Plumbago auriculata Lam. (Plumbaginaceae) is a medicinal flowering shrub which produces plumbagin that shows diverse pharmacological attributes. P auriculata accumulates a very important napthaquinone, plumbagin which exhibits a wide range of medicinal properties. The present study is aimed at in vitro propagation of P auriculata and a comparative quantification of plumbagin in in vitro and in vivo grown plants. Direct shoot regeneration was induced from the nodal explants of P auriculata. Murashige and Skoog medium supplemented with different combination of 6-Benzylaminopurine (BAP) and 1-Naphthaleneacetic acid (NAA). Best response was obtained with BAP 1.5 mg/L and NAA 2.0 mg/L after 15 days in in vitro culture. Maximum number of roots were induced on ½ strength MS medium supplemented with 2% sucrose (w/v) and 0.7 mg/L Indole-3-acetic acid. Plumbagin was extracted by microwave-assisted extraction method and content was estimated from stem, leaf and root of both propagated plants by HPTLC. It was found that the roots of both in vivo (0.01% w/w) and in vitro (0.066% w/w) grown plants contain the highest amount of plumbagin. In vitro grown roots produced five-fold more plumbagin as compared to in vivo regenerated roots. Maximum increase of plumbagin production was observed in the in vitro grown stem i.e., seven-fold as compared to in vivo induced stem. In vitro propagation of plant provides a rapid and continuous supply of plumbagin while preserving the natural resource. [ABSTRACT FROM AUTHOR]

Phytofabrication of the nanoparticles with exotic shape and size is an attractive area where nanostructures with noteworthy physicochemical and optoelectronic properties that can be significantly employed for photocatalytic dye degradation. In this study a medicinal plant, Plumbago auriculata leaf extract (PALE) was used to synthesize zinc oxide particles (ZnOPs) and silver mixed zinc oxide particles (ZnOAg1Ps, ZnOAg10Ps, ZnO10Ag1Ps) by varying the concentration of the metal precursor salts, i.e. zinc acetate and silver nitrate. The PALE showed significantly high concentrations of polyphenols, flavonoids, reducing sugar, starch, citric acid and plumbagin up to 314.3 ± 0.33, 960.0 ± 2.88, 121.3 ± 4.60, 150.3 ± 3.17, 109.4 ± 2.36, and 260.4 ± 8.90 μg/ml, respectively which might play an important role for green synthesis and capping of the phytogenic nanoparticles. The resulting particles were polydispersed which were mostly irregular, spherical, hexagonal and rod like in shape. The pristine ZnOPs exhibited a UV absorption band at 352 nm which shifted around 370 in the Ag mixed ZnOPs with concomitant appearance of peaks at 560 and 635 nm in ZnO10Ag1Ps and ZnOAg1Ps, respectively. The majority of the ZnOPs, ZnOAg1Ps, ZnOAg10Ps, and ZnO10Ag1Ps were 407, 98, 231, and 90 nm in size, respectively. Energy dispersive spectra confirmed the elemental composition of the particles while Fourier transform infrared spectra showed the involvement of the peptide and methyl functional groups in the synthesis and capping of the particles. The composites exhibited superior photocatalytic degradation of methylene blue dye, maximum being 95.7% by the ZnOAg10Ps with a rate constant of 0.0463 s−1 following a first order kinetic model. The present result clearly highlights that Ag mixed ZnOPs synthesized using Plumbago auriculata leaf extract (PALE) can play a critical role in removal of hazardous dyes from effluents of textile and dye industries. Further expanding the application of these phytofabricated composites will promote a significant complementary and alternative strategy for treating refractory pollutants from wastewater.

The tropical plant Plumbago auriculata can tolerate subzero temperatures without induction of apoptosis after cold acclimation in autumn, making it more cold tolerant than conventional tropical plants. In this study, we found that low temperatures significantly affected the photosynthetic system of P. auriculata. Using transcriptome sequencing, PaDREB1A was identified as a key transcription factor involved in the response to cold stress in P. auriculata. This transcription factor may be regulated by upstream JA signaling and regulates downstream ERD4 and ERD7 expression to resist cold stress. Overexpression of PaDREB1A significantly enhanced freezing resistance, protected the photosynthetic system, and enhanced the ROS scavenging mechanism under cold stress in Arabidopsis thaliana. Additionally, PaDREB1A significantly enhanced the expression of CORs and CAT1 in A. thaliana, which further activated the downstream pathway to enhance plant cold tolerance. This study explored the possible different regulatory modes of CBFs in tropical plants and can serve as an important reference for the introduction of tropical plants to low-temperature regions.

The tropical plant Plumbago auriculata can tolerate subzero temperatures without induction of apoptosis after cold acclimation in autumn, making it more cold tolerant than conventional tropical plants. In this study, we found that low temperatures significantly affected the photosynthetic system of P. auriculata. Using transcriptome sequencing, PaDREB1A was identified as a key transcription factor involved in the response to cold stress in P. auriculata. This transcription factor may be regulated by upstream JA signaling and regulates downstream ERD4 and ERD7 expression to resist cold stress. Overexpression of PaDREB1A significantly enhanced freezing resistance, protected the photosynthetic system, and enhanced the ROS scavenging mechanism under cold stress in Arabidopsis thaliana. Additionally, PaDREB1A significantly enhanced the expression of CORs and CAT1 in A. thaliana , which further activated the downstream pathway to enhance plant cold tolerance. This study explored the possible different regulatory modes of CBFs in tropical plants and can serve as an important reference for the introduction of tropical plants to low-temperature regions. [ABSTRACT FROM AUTHOR]

Blue flowers, which are rare, have long been a focus for researchers engaged in colored flower breeding. In this study, Plumbago auriculata, a plant with blue flowers, and its white flower forma Plumbago auriculata f. alba were used as research materials. Flower color quantification, environmental scanning electron microscopy (ESEM) observation of petal epidermal cells, and determination of the cell sap pH were carried out; moreover, metabolomic analysis was used to analyze the flavonoid metabolites of both types of petals. The results showed that the flower color of P. auriculata was bluish violet, and there was no significant difference in the epidermal cell distribution of the white and blue petals. The key substance that determined the bluish violet flower color was cyanidin-3-O-(6″-p-coumaroylglucoside) (Cy3-pC·G). Compared to the white petal cells, the blue petal cells exhibited up to 40 upregulated flavonoid compounds that were copigments. Together with the significantly increased pH (5.92 ± 0.12) of the petal cell sap, these copigments affected the color presentation of Cy3-pC·G, causing the final petal color of P. auriculata to be bluish violet. The results of this study indicate that cyanidin is an important anthocyanidin in blue flowers, which provides new insights into the breeding of blue flowers. [ABSTRACT FROM AUTHOR]

Plumbago auriculata Lam. is an ornamental plant native to South Africa and widely cultivated in China, but the cultivated plants are dominated by a single variety. The development of new varieties is of great commercial interest, and genetic diversity is the foundation of breeding programs. In this study, 85 progenies were obtained by crosses between Plumbago auriculata and Plumbago auriculata f. alba. The genetic diversity of these hybrids was evaluated using horticultural traits and ISSR and SRAP markers. Of the 25 horticultural traits evaluated, the largest variation was found in the beginning of the blooming period, and sepal length was the least variable trait. Correlation analysis showed that the wider the plant, the greater the number of inflorescences and the earlier the flowering. Seven factors explained 65.171% of the total variance; the first factor was leaf morphology, and the second factor was flower morphology. The genetic diversity of the 85 progenies was analyzed using seven pairs of SRAP primers and eight ISSR primers. The average number of effective alleles for 85 hybrids was 1.638, and the average Shannon index value was 0.507. The Nei genetic similarity coefficient indicated that the similarity between WLBS and WSBL was the highest, while that between BLWS and BSWL was the lowest. Analysis of molecular variance (AMOVA) indicated that the main variation was within populations. Cluster analysis based on horticultural traits and molecular markers divided all progenies into seven and five groups, respectively, and there were obvious differences between the two clusters. In this study, we created intermediate materials for future breeding, taking the first step in the cross-breeding of P. auriculata. [ABSTRACT FROM AUTHOR]

Heteromorphic self-incompatibility (HetSI) is a strategy used to prevent selfing while favouring outcrossing in angiosperm. Although the genome, proteome and metabolome of homomorphic self-incompatibility (HomSI) have been investigated, metabolome findings have shown that energy deficiency is one of the factors leading to HomSI. However, the mechanism of HetSI remains unclear. This study investigates the alterations of metabolite fluxes in HetSI. Here, metabolic changes present in dimorphic styles as well as between self-incompatibility (SI) and self-compatibility (SC) pollinations of Plumbago auriculata Lam were simultaneously determined by gas chromatography–mass spectrometry (GC–MS). Fifty-three metabolites, mainly including other organic acids, amino acids, carbohydrates/glycosides, fatty acids/lipids, amines, amides, flavonoids and alcohols, were detected. The overall results showed that carbohydrates, which may affect pollen germination and pollen tube growth rate on stigmas, were abundant in S (short styles without pollination). Moreover, energy deficiency may not be a reason for HetSI because we found inflated levels of metabolites in SI pollinations. This study provided detailed insight into metabolic changes in HetSI and evidence for further studies of HetSI. [ABSTRACT FROM AUTHOR]

Plumbago auriculata Lam. (Plumbaginaceae) is an ornamental/medicinal flowering shrub. However, it could be stop growing under 5 °C resulting in its poor germplasm resources. Increasing the tolerance of polyploids to environmental stress will enrich its germplasm resources. In this study, we thus employed the stem segments and buds exposed to pendimethalin and trifluralin in vitro to conduct an effective polyploid protocol, in which buds were cultured for 7 days in MS medium with 800 μM. In this study, we have developed a novel polyploid identification method based on accuracy and efficiency. Early screening was performed based on the morphological characteristics of this plants, and then polyploidy was determined by flow cytometry. The number of chromosomes was determined by the chromosomal accounting. At the anatomical level, in comparison with diploids, the root parenchyma, stem collenchyma and tetraploid spongy tissues were thickened, the guard cell size and vascular bundles number were increased, and the stomata were widened; but the stomatal density was decreased. After 24 h of cold stress, the maximal quantum yield of photosystem II (Fv/Fm) and maximum primary yield of photochemistry of PSII (Fv/Fo) of diploids decreased significantly. Conversely, the minimal value of chlorophyll a fluorescence (Fo), relative electrical conductivity and malondialdehyde increased markedly. Accordingly, the cold tolerance of the tetraploids presented better than these of the diploids. Taken together, our study has first developed an effective protocol to obtain and identify the tetraploid of P. auriculate plants. Furthermore, it was proved that this polyploid has presented improving cold tolerance and enriching phenotypic properties. These findings could be useful for improving cold-tolerance breeding and enriching genetic diversity of P. auriculate plants. Key message: We used stem segments and buds exposed to pendimethalin and trifluralin in vitro to conduct polyploids of Plumbago auriculata and compared characterizations including cold tolerance between diploids and polyploids. [ABSTRACT FROM AUTHOR]

Plumbago scandens L. (Plumbaginaceae) occurs in all regions of Brazil. It has been described as toxic to cattle and goats. Caustic lesions in the upper digestive tract characterize poisoning. P. scandens contains a naphthoquinone named plumbagin, which presents high cytotoxic activity. Plumbago auriculata Lam., a widely used ornamental plant, is considered potentially toxic, but there is limited data about its toxicity. This work aimed to validate analytical methodologies for determining the levels of plumbagin in samples of leaves, stems, and rumen content to be used as an auxiliary chemical marker in the laboratory diagnosis of intoxication. One methodology used thin layer chromatography (TLC), and another used high-performance liquid chromatography (HPLC). The presence of palisade grass (Urochloa brizantha (Hochst. ex A.Rich.) R.D.Webster), Guinea grass (Megathyrsus maximus (Jacq.) B.K.Simon & S.W.L.Jacobs), corn silage, and rumen content did not interfere with plumbagin in the two methodologies. The TLC methodology generates qualitative results but is simple to implement and has a low cost. The HPLC methodology showed a limit of detection (LOD) of 0.01 μg/mL and a limit of quantification (LOQ) of 0.05 μg/mL. Leaf and stem samples of P. scandens evaluated showed high levels of plumbagin (0.261 ± 0.087 % and 0.327 ± 0.055 %, respectively). In contrast, leaves of P. auriculata did not show detectable levels of the toxin, and some stem samples showed low levels (up to 0.000114 %). Thus, these methodologies can be used to confirm or rule out the consumption of P. scandens in rumen content from animals suspected of poisoning. [Display omitted] • TLC and HPLC methods for detecting plumbagin from Plumbago scandens in rumen and plant samples were validated. • The leaves and stem of Plumbago scandens showed high levels of plumbagin. • Plumbago auriculata showed no detectable levels in the leaves and low levels in the steams. [ABSTRACT FROM AUTHOR]

This work reports the synthesis of silver nanoparticles (AgNPs) using aqueous extract of Plumbago auriculata, and evaluates their antibacterial and larvicidal activities. The synthesized silver nanoparticles were characterized by various spectroscopy techniques, such as FTIR, XRD, TEM, EDX, Zeta potential, and DLS. The synthesized AgNPs exhibited significant antibacterial activity against Gram-positive and Gram-negative bacteria, such as Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae. Furthermore, synthesized nanoparticles inhibited the fourth instars larvae of Aedes aegypti and Culex quinquefasciatus at the concentration of 45.1 and 41.1 µg/mL respectively. Results of dose-dependent studies showed that synthesized nanoparticles were also effective at low concentrations. Molecular docking studies performed with the salivary protein and odorant-binding protein of Aedes aegypti and Culex quinquefasciatus demonstrated that the naphthoquinone compound plumbagin exhibited reliable binding affinity towards the two enzymes. The findings thus reveal that the plant extract and its nanoparticles can be a better alternative to available chemicals to control mosquitos.

This study interprets the structure and provides insights on the phyto-compounds of the leaves and calyces of Plumbago auriculata and evaluates its potential as a medicinal plant based on the presence of these compounds. Structure and possession of phyto-compounds were determined using light and electron microscopy and various histochemical tests. Glandular capitate and non-glandular uniserate trichomes were present on the surface of the calyx. Glandular trichomes bear a close resemblance to the digestive glands of the genus Drosera. Salt glands present on the leaf surface were abundant on the abaxial surface and revealed the presence of "transfer cells" reported for the first time in the genus. Abundant mitochondria, mini vacuoles, ribosomes, dictyosomes and rough endoplasmic reticulum cisternae were actively involved in the secretory process. Histochemical staining also revealed the presence of alkaloids and phenolic compounds that are of medicinal importance used to treat multiple ailments and also function as chemical deterrents in plants. Overall, this study contributes to the existing body of knowledge on the secretory structures of P. auriculata and provides new insights on the ultrastructural and histochemical aspects of the species. • This study introduces for the first time the presence of transfer cells in the salt glands in the genus Plumbago. • Histochemical results presented in this study was reported for the first time in Plumbago auriculata. [ABSTRACT FROM AUTHOR]

In the present work, silver nanoparticles have been biosynthesized by utilizing the alcoholic extract ofPlumbago auriculata. The optimization of reaction conditions was carried out by monitoring the reactions with the help of UV–Visible absorption spectroscopy. The characterization of AgNP was carried out by infrared spectroscopy, transmission electron microscopy and X-Ray diffraction (XRD) studies. The biogenic AgNPs were tested againstMycobacterium tuberculosisusing Microplate Almar Blue assay (MABA) and their antioxidant activity was also evaluated. The silver nanoparticles were also assessed for their reducing activity against organic dyes. The AgNPs were spherical in shape with size ranging from 15 to 45 nm with face centered cubic geometry as revealed by XRD analysis. The AgNPs possessed good antitubercular activity with MIC value of 1.6 μg/ml and these also exhibited promising antioxidant activity with IC50value of 28.2. Furthermore, AgNPs also reduced congo red within 2 h and malachite green was degraded within 40 min. The present work demonstrated the utilization ofP. auriculatafor biosynthesis of AgNP which could be a potential candidate for antitubercular drug development and it could also be used as an antioxidant agent. The application of AgNP in reducing agent can be further extended and evaluated for purification of effluent water from textile industries. [ABSTRACT FROM AUTHOR]

Background: Historically, plants have proven their value as a source of phytochemicals with therapeutic potentials and recently they play an important role in the discovery of novel drugs. Objectives: The current study aimed to investigate new antiobesity drugs from Plumbago europaea and Plumbago auriculata through the inhibition of the adsorption of dietary lipids. In vitro porcine pancreatic lipase inhibitory tests were conducted with weight reduction property as well as this study aimed to explore the antioxidant potential and to estimate total phenolic, flavonoid, and tannin contents in both of the studied species. Methods: Antioxidant capacity was evaluated using ferric reducing antioxidant power and DPPH assays, and porcine pancreatic lipase inhibitory tests were conducted using the UV spectrophotometric method, while total flavonoid, phenol, and tannin contents were estimated using standard phytochemical analytical methods. Results: Antioxidant potential and total flavonoid, phenol, and tannin contents of P. europaea were significantly higher than those of P. auriculata, and both of the studied species have potential antiobesity activity in comparison with orlistat. Conclusion: Results of the present study show that both of the studied Plumbago species consist of bioactive compounds that can act as lipase inhibitors and therefore can be useful for the development of functional foods against obesity. It can also be used as a source of lead compounds for designing new antiobesity drugs. Further isolation, identification, and characterization of phyto-active compounds responsible for antiobesity action are required to evaluate the full therapeutic potentials of these plants. [ABSTRACT FROM AUTHOR]

In order to explain the main reasons for the low natural seed-set ratio of Plumbago auriculata, which can contribute to the large-scale production of P. auriculata and also help to get rid of the situation that the seeds over-rely on the import from abroad at the same time. We attempted to measured the dynamic changes of the pollen viability by the method of TTC and the stigma receptivity and the method of Benzidine-H2O2 in two ways, which respectively focused more on the pollination biology and the breeding system. And we also estimated the type of the breeding system pollen-ovule ratio(P/O), and verified the out-crossing index(OCI)by the pollination experiments. The results of the experiment were as follows:(1)About P. auriculata, the maturity time of the L-type female organs and the S-type male organs,and also that of the L-type female organs and the L-type male organs overlaped a lot,there was no obvious difference in the maturity time between the female and the male organs. On the other hand,the maturity time of the S-type female organs and the L-type male organs,and also that of the S-type female organs and the S-type male organs overlaped a little,but the continuous blossoming pattern of P. auriculata reduced reproductive isolation caused by the different maturity time of the male and the female sexual organs.(2)The P/O of L-type was 502±52.30,the P/O of S-type 482.7±87.91,both the out-crossing index of the L-type and that of the S-type are 4. The result of the manual-controlled pollination experiments suggested that the breeding system of P. auriculata was obligate outcrossing and it had the feature of the heteromorphic incompatibility. To sum up,the reasons for the low natural seed-set ratio of P. auriculata were the combination of both internal and external factors. Among these factors,the short same maturity time of the male and the female sexual organs was not the main reason,while the strong self-incompatibility of P. auriculata itself might be the key internal factor to lead to the low natural seed-set ratio. Due to the breeding system of the obligate outcrossing,it was quite necessary for P. auriculata to had the pollination medium to lead to the successful pollination. However,the introduction environment and the original environment were distinctly different,in addition,the mode of the scattered blooming led to the cross-pollinator,which might be the key external factor of low success rate of outcrossing. In a conclusion,the improvement of the natural seed-set ratio of P. auriculata should mainly focus on overcoming the incompatibility of P. auriculata itself,and also properly bringing in some insects as the safe medium. This would provide the theoretical guidance and the application foundation for the expansion of this kind of species resource and also the acceleration of the promotion and the application. [ABSTRACT FROM AUTHOR]

The role of distyly in the heteromorphic selfing incompatibility is a controversial question In order to dicusse this question, we chose Plumbago auriculata as material, observed it floral morphs, regulated the height of styles,polinate these style,and analyzed the fruit set. The results were as folows: (1) Significant differences were found in floral tube width,floral tube length,pistil height,stamen height,stigma length,anther width,stamen (L) and style (S) height There was no significant difference in corola width,petal length, calyx length, ovary diameter, an ther length,stamen (S) and style (L) height (S) and style (L); (2) Suitable IAA,NAA and GA could regulate the length of style; (3) There was no significant difference in fruit set of blank control and regulated style. There was typical dimorphism in the floral morphs of P. auriculata It was evolutionary adaptation strategy for reciprocal herkogamy in P. auriculata. The spatial distribution of sex-organ had absolutely no afect on incompatibility through the effective spread of legal polen,incompatibility of abnormal shape flower could be seen more clearly on physiological mechanism. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of different cutting facilities, cutting time and hormone treatments on the survival and rooting of Plumbago auriculata summerwood cuttings. The results showed that a new type of cutting facility used in this study significantly improved the survival rate of P. auriculata summerwood cuttings; the best time for summerwood cutting of P. auriculata was May; various hormone treatments significantly improved the rooting rate of P. auriculata summerwood cuttings; the optimal concentrations of NAA, IAA and IBA were 1 000, 1 500 and 1 500 mg/L, respectively. This study provided scientific basis for the establishment of summerwood cutting propagation technology system of P. auriculata. [ABSTRACT FROM AUTHOR]

Abstract: A natural compound plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone) was isolated from the leaves of Plumbago auriculata and found to inhibit the enzyme, 8-amino-7-oxononanoate synthase (AONS, also known as 7-keto-8-aminopelargonate synthase, KAPAS) an IC50 of 2.1μM in vitro. Biotin supplement significantly rescued the plant injury caused by the plumbagin treatment, and this result confirmed the target site, AONS. Foliar application of 1000∼2000μg/mL plumbagin in a greenhouse condition showed lethal activity against eight species of weeds, containing three grass species of Sorghum bicolor, Echinochloa crus-galli, Digitaria sanguinalis and five broad leaf species of Solanum nigrum, Aeschynomene indica, Abutilon avicennae, Xanthium strumarium, Calystegia japonica. Field trial of foliar application with plumbagin 2000μg/mL have successfully controlled 10∼15 leaf-stages and 2∼3m vine lengths of Sicyos angulatus at the natural habitats around riparian zone in the Nam-Han River in Korea. Visual symptom of desiccation might be induced by the physiological cellular leakage which was significantly dose dependent on the plumbagin treatment regardless of light. [Copyright &y& Elsevier]

Abstract: Plants with hermaphrodite flowers risk conflict between male and female sexual function due to close proximity of sexual organs. Heterostyly, a genetic floral polymorphism characterized mainly by reciprocal herkogamy, may reduce this sexual conflict by increasing the precision of pollen transfer between morphs. This sexual organ reciprocity is often associated with various ancillary characters and a heteromorphic incompatibility system. Here we describe the morphometrics associated with heterostyly and ancillary characters in Plumbago auriculata. Using controlled pollination experiments, we show that this species has a heteromorphic incompatibility system. We also document the fauna of long-proboscid fly and butterfly pollinators in a P. auriculata population in KwaZulu-Natal, South Africa. [Copyright &y& Elsevier]

The effect of drought on the growth and gas exchange of six bedding plant species--agastache [Agastache urticifolia (Benth.) O. Kuntze 'Honeybee Blue'], dusty miller (Cineraria maritima L. 'Silverdusty'), petunia (Petunia xhybrida 'Wave Purple'), plumbago (Plumbago auriculata Lam. 'Escapade'), ornamental pepper (Capsicum annuum L. 'Black Pearl'), and vinca [Catharanthus roseus (L.) G. Don 'Titan'l--was quantified under greenhouse conditions. Seeds were sown in January and seedlings were grown in the greenhouse until 18 Apr., when two irrigation treatments--drought (D, ≈18% volumetric moisture content at reirrigation) and control (C, ≈25% volumetric moisture content at reirrigation)--were initiated. Leaf net photosynthetic rate (P.), stomatal conductance (gs), and transpiration (E) were determined in response to a range of substrate moisture content (from ≈5% to 30% by volume) and temperature (from 20 °C to 40 °C). Dry weight of agastache, ornamental pepper, and vinca was unaffected by drought, whereas that of other species was reduced. Leaf area of plumbago and height of plumbago and vinca were reduced by drought. As substrate moisture content decreased from 25% to 10%, Pn, E, and gs decreased linearly in all species except petunia and plumbago. Leaf net photosynthetic rate of all species declined as leaf temperature increased from 20 °C to 40 °C. In contrast, E of all species, except petunia, increased as temperature increased. Transpiration rate of petunia increased as temperature increased from 20 °C to 30 °C, and then decreased between 30 °C and 40 °C. Although petunia had the highest Pn among the tested species, its Pn and gs declined more rapidly compared with the other species as temperature increased from 20 °C to 40 °C or as substrate moisture content decreased, indicating that petunia was most sensitive to high temperature and drought. [ABSTRACT FROM AUTHOR]

• We investigated the inheritance of main flower characteristics via a heterosis analysis and major gene plus polygene genetic analysis. • Transgressive segregation of the main flower characteristics was commonly observed in the F1 generation, except for corolla color value. • Inflorescence diameter and inflorescence length were best fit by the A-0 model, indicating that they were controlled by only polygenes. • Number of flowers per inflorescence, beginning of the blooming period, inflorescence number, flower diameter and length were controlled by major genes. The ornamental characteristics of Plumbago auriculata are mainly reflected in the floral organ. Exploring the genetic inheritance of flower characteristics is important for breeding new varieties. In this study, F 1 segregating populations were obtained by using artificial hybridization (direct cross and reciprocal cross) between P. auriculata and its variant P. auriculata f. alba. A heterosis analysis and mixed major gene plus polygene inheritance model were used to investigate the inheritance of eight flower characteristics in the F 1 generation: inflorescence length (IL), inflorescence diameter (ID), number of flowers per inflorescence (NFI), beginning of the blooming period (BBP), inflorescence number (IN), flower diameter (FD), flower length (FL) and corolla color value (CCV). In addition to the CCV, the other flower characteristics showed continuous unimodal and skewed distributions, which indicated that these characteristics were quantitative and controlled by polygenes. Although transgressive heterosis was observed only for BBP in both combinations, transgressive segregation was commonly observed, except for CCV in the F 1 generation; these findings could facilitate the selection of beneficial individuals for breeding. Genetic analysis revealed that NFI could be described by a B-3 genetic model via two pairs of additive major genes; BBP could be followed by a B-2 genetic model via two pairs of additive-dominance major genes; both FL and FD could be described by a B-6 genetic model via two pairs of major genes that were equally dominant; IN was best fit by the A-1 model, which was controlled by a pair of additive-dominant-epistatic major genes; and IL and ID were best fit by the A-0 model, indicating that both characteristics were controlled by only polygenes. The heritability of the major genes controlling the NFI, BBP, FD, FL and IN traits were 92.58 %, 94.40 %, 63.42 %, 54.23 % and 65.67 %, respectively, indicating that these five characteristics were less affected by the environment. These results can provide some reference for quantitative trait locus (QTL) mapping and molecular marker-assisted breeding of the main flower characteristics in P. auriculata. [ABSTRACT FROM AUTHOR]

This work reports the synthesis of silver nanoparticles (AgNPs) using aqueous extract of Plumbago auriculata, and evaluates their antibacterial and larvicidal activities. The synthesized silver nanoparticles were characterized by various spectroscopy techniques, such as FTIR, XRD, TEM, EDX, Zeta potential, and DLS. The synthesized AgNPs exhibited significant antibacterial activity against Gram-positive and Gram-negative bacteria, such as Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae. Furthermore, synthesized nanoparticles inhibited the fourth instars larvae of Aedes aegypti and Culex quinquefasciatus at the concentration of 45.1 and 41.1 µg/mL respectively. Results of dose-dependent studies showed that synthesized nanoparticles were also effective at low concentrations. Molecular docking studies performed with the salivary protein and odorant-binding protein of Aedes aegypti and Culex quinquefasciatus demonstrated that the naphthoquinone compound plumbagin exhibited reliable binding affinity towards the two enzymes. The findings thus reveal that the plant extract and its nanoparticles can be a better alternative to available chemicals to control mosquitos. [ABSTRACT FROM AUTHOR]