Untangling the taxonomy of Phlogacanthus pulcherrimus (Acanthaceae) newly recorded from Vietnam

The present work is an effort to untangle the taxonomy of Phlogacanthus pulcherrimus, a poorly known species reported here for the first time for the flora of Vietnam. Fresh specimens of this species were collected from three localities in Southern Vietnam. They provided new insights to its appearance and morphology. Phlogacanthus pulcherrimus can be distinguished from the morphologically close P. geoffrayi and P. turgidus by oblanceolate-obovate, light to dark purple flower-subtending bracts, oblanceolate bracteoles, and staminodes 1 mm long. The corolla of the Vietnamese specimens of P. pulcherrimus is uniformly dark purple outside. A detailed description, photographs, and information on habitat, ecology and distribution of P. pulcherrimus are provided. Typification of this name is performed, and a specimen at K (K000885620) is designated as a lectotype.

Green Synthesis of Silver Nanoparticles Using Catharanthus roseus Flower Extracts and the Determination of Their Antioxidant, Antimicrobial, and Photocatalytic Activity

The present study describes the antioxidant, antimicrobial, and photocatalytic activity of silver nanoparticles (AGNPs) synthesized using six varieties of Catharanthus roseus flower extracts for the first time. Initially, the synthesized AgNPs were visually confirmed by color change. Further, the formation, size, and shape of the synthesized AgNPs were characterized by UV-Vis spectroscopy and scanning electron microscopy (SEM). The SEM image of purple flower AgNPs and the calculated bandgap energies of the synthesized AgNPs showed that the synthesized AgNPs were in the range of 0–30 nm. Qualitative phytochemical analysis revealed the presence of the phytocompounds that were responsible for the capping, formation, bioreduction, and stabilization of AgNPs. The antioxidant ability of the AgNPs and their respective flower extracts were analyzed using TFC, TPC, TAC, DPPH, FRAP, and IC50 assays. The results of the antioxidant assays indicated that the AgNPs showed higher antioxidant activity compared to their respective flower extracts. The synthesized AgNPs showed significant antimicrobial activity against Gram-negative Escherichia coli compared to Gram-positive Staphylococcus aureus assayed using the agar well diffusion method. Furthermore, the photocatalytic activity of the synthesized purple flower AgNPs at two different concentrations 5000 ppm and 333 ppm was analyzed by the removal of methyl orange dye from an aqueous solution under sunlight irradiation in the presence of NaBH4 catalyst. Results indicated that 333 ppm purple flower AgNPs exhibited an efficient photocatalytic activity in the degradation of methyl orange compared to 5000 ppm purple flower AgNPs in 20 minutes. Thus, the results obtained indicated that Catharanthus roseus is an ecofriendly source for the green synthesis of AgNPs which can be used as a novel antioxidant, antimicrobial, and photocatalytic agent; thereby, it can be used in a variety of applications to improve the quality of human life.

Transcriptome-Wide Analysis Reveals Key DEGs in Flower Color Regulation of Hosta plantaginea (Lam.) Aschers

Background: Hosta plantaginea (Lam.) Aschers (HPA), a species in the family Liliaceae, is an important landscaping plant and herbaceous ornamental flower. However, because the flower has only two colors, white and purple, color matching applications are extremely limited. To date, the mechanism underlying flower color regulation remains unclear. Methods: In this study, the transcriptomes of three cultivars—H. plantaginea (HP, white flower), H. Cathayana (HC, purple flower), and H. plantaginea ‘Summer Fragrance’ (HS, purple flower)—at three flowering stages (bud stage, initial stage, and late flowering stage) were sequenced with the Illumina HiSeq 2000 (San Diego, CA, USA). The RNA-Seq results were validated by qRT-PCR of eight differentially expressed genes (DEGs). Then, we further analyzed the relationship between anthocyanidin synthase (ANS), chalcone synthase (CHS), and P450 and the flower color regulation by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Eukaryotic Orthologous Groups (KOG) network and pathway enrichment analyses. The overexpression of CHS and ANS in transgenic tobacco petals was verified using qRT-PCR, and the petal colors associated with the overexpression lines were confirmed using absorbance values. Results: Over 434,349 transcripts were isolated, and 302,832 unigenes were identified. Additionally, through transcriptome comparisons, 2098, 722, and 606 DEGs between the different stages were found for HP, HC, and HS, respectively. Furthermore, GO and KEGG pathway analyses showed that 84 color-related DEGs were enriched in 22 pathways. In particular, the flavonoid biosynthetic pathway, regulated by CHS, ANS, and the cytochrome P450-type monooxygenase gene, was upregulated in both purple flower varieties in the late flowering stage. In contrast, this gene was hardly expressed in the white flower variety, which was verified in the CHS and ANS overexpression transgenic tobacco petals. Conclusions: The results suggest that CHS, ANS, and the cytochrome P450s-regulated flavonoid biosynthetic pathway might play key roles in the regulation of flower color in HPA. These insights into the mechanism of flower color regulation could be used to guide artificial breeding of polychrome varieties of ornamental flowers.

Amorphophalus titanum Bunga Endemik Sumatra

Amorphophalus titanum is a Sumatran endemic plant and is one of Indonesia's rare plants. Amorphophalus titanum naturally spread throughout the forests of Sumatra as a plant under the canopy (undergrowth) on calcareous soil. The purpose of this article to discuss the potential, extinction status, distribution and characteristics or morphology of Amorphophalus titanum. The roots in Amorphophallus titanum consist of tubers. The stem owned by Amorphophallus titanium is a pseudo stem composed of addicted leaf midribs. Leaf blade with a diameter of about 7 m, leaf elliptical pine leaf, 40 cm long, tapered tip, if touched like a skin, the upper surface is green, rather shiny. Inflorescence on the corpse flower is a collection of small male and female flowers. The place where flowers are attached to is at the base of the cob. Spadiks is yellow and is arrouded by a reddish-purple flower sheath. Amorphophallus titanum used as an ornamental plant because of its unique shape and is able to attract the attention of many visitors.

Amorphophalus titanum Bunga Endemik Sumatra

Amorphophalus titanum is a Sumatran endemic plant and is one of Indonesia's rare plants. The purpose of this article to discuss the potential, extinction status, distribution and characteristics or morphology of Amorphophalus titanum. The roots in Amorphophallus titanum consist of tubers. The stem owned by Amorphophallus titanium is a pseudo stem composed of addicted leaf midribs. Leaf blade with a diameter of about 7 m, leaf elliptical pine leaf, 40 cm long, tapered tip, if touched like a skin, the upper surface is green, rather shiny. Inflorescence on the corpse flower is a collection of small male and female flowers. The place where flowers are attached to is at the base of the cob. Spadiks is yellow and is arrouded by a reddish-purple flower sheath. Amorphophallus titanum used as an ornamental plant because of its unique shape and is able to attract the attention of many visitors.

KERAGAMAN MORFOLOGI Hoya purpureofusca Hook.f. ASAL TAMAN NASIONAL GUNUNG GEDE PANGRANGO

Hoya purpureofusca Hook.f. (Apocynaceae: Asclepiadoideae) has been used as an ornamental plant and the international trade of this species has become increasing. This species has restricted distribution on the high elevation of Java and Bali mountains. This epiphyte climber has succulent leaves and umbellate delicate flowers. Flower has star shape, succulent and waxy, purple., c.1 cm in diameter. The observation on the morphological characteristic is aimed to select the best sample for ornamental plant. The total of 17 observed samples were obtained from three populations at Gunung Gede Pangrango National Park, West Java, Indonesia. The selection was based on the node length, size of the leaves, and flower number, size and color. The result showed that P01 from Cibodas could be developed as leaf ornamental plant, because its shortest node and small leaves. SP1 from Selabintana could be developed as flower ornamental plant, it has numerous, larger and deep purple flower. SP1 and P01 have the farest relatives distance among all observed accessions, but still have a similarity of 75%.

Molecular Characterization of Vitex agnus-castus L. (Verbenaceae) Populations Grown in Aydin, Turkey

In this study, we performed a genetic diversity analysis using RAPD markers for some Vitex agnus-castus populations grown in Aydin, Turkey. Total genomic DNA isolation from the leaves of Vitex agnus-castus was performed using a commercial kit. Seven RAPD primers (OPA-02, OPA-05, OPA-13, OPA-15, OPA-16, OPA-18, OPA-20) were used to determine genetic diversity among populations. Polymerase Chain Reaction (PCR) was performed with all genomic DNA samples and primers. PCR products were run in agarose gel electrophoresis and visualized under UV light. The amplified products were scored as bands (1) and no bands (0) for all gel images and their matrix files were generated. A total of 36 characters were obtained from the primers. Phylogenetic relationships and genetic distances between the cultivars were calculated by using the PAUP* (Phylogenetic Analysis Using Parsimony and other methods) program. According to PAUP analysis, the closest genetic distances were between Çine pink flower and Çakmar purple flower, and Çakmar pink flower and Çakmar purple flower populations with a value of 0.05556; and the greatest genetic distance was between Çakmar pink flower and Köşk purple flower populations with a value of 0.36111. In the phylogenetic analysis obtained using UPGMA algorithms, the phylogenetic tree consisted of four groups. The results suggest that RAPD markers are useful tools for determining genetic relationships among Vitex agnus-castus genotypes.