The complete chloroplast genome of Philodendron hederaceum (Jacq.) Schott 1829 (Alismatales: Araceae).

Philodendron hederaceum (Jacq.) Schott 1829, a species of the Araceae family, is a foliage plant of ornamental value. The complete chloroplast genome sequence of Philodendron hederaceum was obtained by the de novo assembly of NovaSeq 6000 (Illumina Co., San Diego, CA) paired-end short reads and Oxford Nanopore long reads. The complete chloroplast genome of P. hederaceum was 168,609 bp in length, with a large single-copy (LSC) region of 94,393 bp, a small single-copy (SSC) region of 25,774 bp, and a pair of identical inverted repeat regions (IRs) of 24,221 bp. The genome contained a total of 129 genes, including 85 protein-coding genes, 36 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes. The phylogenetic analysis of P. hederaceum with 19 related species and two outgroup species revealed the closest taxonomical relationship with Philodendron lanceolatum in the Araceae family.

Prophyll in Monocots: The Starting Point of Lateral Shoot Phyllotaxis.

In monocots, the prophyll (or flower bracteole) is the first leaf of the lateral shoot. Typically, the prophyll occurs in an adaxial position toward the main axis; it bears two teeth at its apex and often two keels on the dorsal side. Some authors have hypothesized that the prophyll appeared in evolution as a result of the fusion of two phyllomes. However, in different monocot taxa, prophyll morphology results from the mechanical pressure of the surrounding organs and it cannot be regarded as two fused leaves. In Commelinaceae, if the lateral shoot develops extravaginally (i.e., penetrates the sheath) and the prophyll is not under pressure, the apical teeth and keels are missing. If the lateral shoot starts development intravaginally and under moderate pressure, the prophyll exhibits keels and a bidentate shape. In the bulbs of Amaryllidaceae, which are under strong pressure, the teeth of the prophyll become more pronounced, and the prophyll is dissected into two distinct lobes. In some monocots, the evolutionary trend leads to complete prophyll reduction. Investigations of lateral shoot phyllotaxis have found that the positions of all the subsequent phyllomes of the lateral shoot are sensitive to the prophyll position; they become rearranged if the prophyll deviates from the standard adaxial location (e.g., becoming oblique or transversal). As a generalization in Amaryllidaceae, I have proposed the axiomatic "phantom" method for modeling the prophyll position and shoot branching in cases of complete prophyll reduction. Using the phantom method, I reinvestigated the structure of sympodial units in Philodendron (Araceae). Previous interpretation of the two-keeled cataphyll as a prophyll appeared to be erroneous. In a new interpretation of the sympodial unit, the prophyll and the subsequent leaf are reduced and the cataphyll is the third leaf in the leaf series. A comparative morphological study in Araceae has revealed that prophylls of vegetative shoots rarely elongate and resemble round scales with obscure boundaries with the main axis. This observation could explain prophyll reduction in Philodendron. As such, the positional control of phyllotaxis by the prophyll may be revealed even when the prophyll is completely reduced.

Philodendron bipinnatifidum anthracnose Caused by Colletotrichum karsti and C. endophytica in Guangxi, China.

Philodendron bipinnatifidum Schott ex Endl (Araceae) is native to South America. It was introduced in Guangdong around the 1980s, and then gradually promoted for use as a landscape ornamental in South China (You et al. 2013). Previous studies showed that an extract of P. bipinnatifidum displayed antinociceptive and anti-inflammatory activities (Scapinello et al. 2019). In August 2019 and June 2020, leaf spot disease was observed on P. bipinnatifidum leaves in Qingxiushan Park, Nanning, Guangxi province, China, with approximately 80% disease incidence. Symptoms began as small brown spots that extended into large, irregular, dark brown, necrotic, sunken lesions. The leaves eventually became yellow and then withered and died. The symptomatic leaves were sampled from three different places in the park. Leaf pieces (5× 5 mm) of three samples were cut from the junction of diseased and healthy leaf tissue, disinfected in 75% (v/v) alcohol for 10 sec, 2% (v/v) sodium hypochlorite for 1 min, and then rinsed three times in sterile distilled water before pieces were incubated on potato dextrose agar (PDA) at 25°C for 7 days. Eighty-one Colletotrichum isolates were obtained, with an 88% isolation rate, and three of these (GBZ7-1, GBZ7-3 and GBZ8-2) were selected for intensive study. After 7 days, the colonies on PDA showed white-to-gray aerial mycelium. Conidia (n=90) were elliptical, single-celled, hyaline, straight, 14.61 ± 0.08 µm × 6.84 ± 0.04 µm (C. karsti), and 15.15 ± 0.11 µm ×5.04 ± 0.04 µm (C. endophytica). Appressoria (n=90) were melanized, subglobose, irregular, 9.57 ± 0.17 µm × 7.18 ± 0.10 µm (C. karsti), and 7.36 ± 0.18 µm × 5.52 ± 0.13 µm (C. endophytica). To confirm morphological identification, the rDNA internal transcribed spacer region (ITS), actin (ACT), calmodulin (CAL), chitin synthase (CHS-1), ß-tubulin 2 (TUB2) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes (Weir et al. 2012) were amplified and sequenced (GenBank accessions Nos. ITS (MZ962373 ~ MZ962375), ACT (OK040200 ~ OK040202), CAL (OK040205 ~ OK040207), CHS-1 (OK040210 ~ OK040212), TUB2 (OK040220 ~ OK040222) and GAPDH (OK040215 ~ OK040217) of GBZ7-1, GBZ7-3 and GBZ8-2 respectively). Phylogenetic analysis was done using RAXML (Version 2.0) based on sequences of multiple loci (ITS, ACT, CAL, CHS-1, TUB2 and GAPDH). Isolates GBZ7-1 and GBZ7-3 were identified as C. karsti and GBZ8-2 as C. endophytica. Pathogenicity tests were performed with the three isolates on 45 asymptomatic attached leaves of nine one-year-old plants (three plants per isolate). Every leaf was punctured at three points using a sterile needle and inoculated with 10 µl of conidial suspension (106spores/ml) on each wound. Wounded leaves treated with sterilized water under the same conditions served as controls. The experiment was repeated three times. All plants were sprayed with water and covered with plastic bags to maintain high humidity. Sunken necrotic lesions were observed on all inoculated leaves after 15 days at 28 °C, whereas no symptoms were observed on the control leaves. C. karsti and C. endophytica were consistently re-isolated from the inoculated leaves which was confirmed by morphology and sequencing, fulfilling Koch's postulates. C. siamense was previously reported as a pathogen on P. bipinnatifidum in China (Ning et al. 2021). To our knowledge, this is the first report of leaf spot caused by C. karsti and C. endophytica on P. bipinnatifidum worldwide. This research may accelerate the development of future epidemiological studies and management strategies for anthracnose caused by C. karsti and C. endophytica on P. bipinnatifidum.

Characterization and Pathogenicity of Colletotrichum Species on Philodendron tatei cv. Congo in Gansu Province, China.

In recent years in China, leaf spot caused by Colletotrichum species has been an emerging disease of Philodendron tatei cv. Congo. From 2016 to 2019, typical symptoms, appearing as circular or ovoid, sunken, and brown lesions with a yellow halo, were commonly observed on P. tatei cv. Congo in and around Lanzhou, Gansu Province, China. Conidiomata were often visible on infected leaf surfaces. Leaf disease incidence was approximately 5 to 20%. A total of 126 single-spored Colletotrichum isolates were obtained from leaf lesions. Multilocus phylogenetic relationships were analyzed based on seven genomic loci (ITS, ACT, GAPDH, HIS3, CAL, CHS-1, and TUB2) and the morphological characters of the isolates determined. These isolates were identified as three Colletotrichum species in this study. A further 93 isolates, accounting for 74% of all Colletotrichum isolates, were described as new species and named as Colletotrichum philodendricola sp. nov. after the host plant genus name, Philodendron; another two isolates were named as C. pseudoboninense sp. nov. based on phylogenetic and morphological relativeness to C. boninense; the other 31 isolates, belonging to the C. orchidearum species complex, were identified as a known species-C. orchidearum. Both novel species C. philodendricola and C. pseudoboninense belong to the C. boninense species complex. Pathogenicity tests by both spray and point inoculations confirmed that all three species could infect leaves of P. tatei cv. Congo. For spray inoculation, the mean infection rate of leaves on the three species was only 4.7% (0 to 12%), and the size on lesions was mostly 1 to 2 mm in length. For point inoculation, 30 days after nonwounding inoculation, the infection rate on leaves was 0 to 35%; in wounding inoculation, the infection rate of leaves was 35 to 65%; wounding in healthy leaves greatly enhanced the pathogenicity of these three species to P. tatei cv. Congo; however, the sizes of lesions among the three species were not significantly different. To our knowledge, this is the first report of Colletotrichum species associated with anthracnose diseases on P. tatei cv. Congo. Results obtained in this study will assist the disease prevention and appropriate management strategies.

Antinociceptive and anti-inflammatory activities of Philodendron bipinnatifidum Schott ex Endl (Araceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Popular medicine use stems of Philodendron bipinnatifidum (Araceae) in inflammation cases, such as in erysipelas, as well as orchitis and rheumatism treatment. The present study, conducted for the first time in literature, investigate the antinociceptive and anti-inflammatory activities of P. bipinnatifidum stems ethyl acetate extract (EPB). MATERIALS AND METHODS: GC/MS and HPLC analysis were performed for EPB extract. We used EPB at 250, 375 and 500 mg/kg (oral route, p.o.) in male Swiss mice. The antinociceptive activity of the plant extract assessed by acetic acid induced writhing and formalin tests. To investigate the possible participation of opioid system in EPB-mediated effects, we previously administered naloxone to the mice. Anti-inflammatory activity was evaluated using carrageenan-induced paw oedema. The open-field test aimed to investigate the possible EPB effects on the locomotor and exploratory activities. To assess the protective role of EPB on carrageenan-induced oxidative stress, the levels of NPSH, TBARS, as well as SOD and CAT activities were evaluated in blood and paw tissue. The acute toxicity of the EPB was investigated using OECD 423 guideline. RESULTS: The EPB chemical analysis by GC/MS and HPLC revealed the presence of flavonoids (luteolin and quercetin) and phytosterols (ß-sitosterol and stigmasterol). The oral treatment with the EPB inhibited mice abdominal writhings (P < 0.01) at 375 and 500 mg/kg, and reduced the formalin effect at the first-phase (500 mg/kg, P < 0.05) and also at the second-phase (500 mg/kg, P < 0.001) of the test. EPB (375 and 500 mg/kg) did not alter spontaneous locomotion in open field test, however the number of fecal bolus was significantly lower for the EPB group at 500 mg/kg when compared to the vehicle group (P < 0.05). The pretreatment with naloxone caused significant inhibition of antinociceptive activity induced by EPB in the formalin test, revealing the possible involvement of opioid receptors. EPB extract administered at 500 mg/kg (p.o.) prevented carrageenan-induced paw oedema (P < 0.05 and 0.01) until 6 h after carragenan injection. Evaluation of TBARS and NPSH levels, SOD and CAT activities in the blood and paw tissue of animals submitted to the carrageenan assay suggested that the anti-inflammatory effect of EPB may be linked to oxidative stress inhibition. The acute administration of the EPB (2000 mg/kg, p.o.) caused no mortality, demonstrating low toxicity. CONCLUSIONS: The extract of P. bipinnatifidum displays antinociceptive and anti-inflammatory activities, causing no toxicological effects. The pharmacological activity of this vegetal species may be related to the presence of flavonoids and phytosterols. Our results support the ethnomedical use of this vegetal species as analgesic and anti-inflammatory agent.

Phylogeny and diversification history of the large Neotropical genus Philodendron (Araceae): Accelerated speciation in a lineage dominated by epiphytes.

PREMISE OF THE STUDY: Philodendron is a large genus of ~560 species and among the most conspicuous epiphytic components of Neotropical forests, yet its phylogenetic relationships, timing of divergence, and diversification history have remained unclear. We present a comprehensive phylogenetic study for Philodendron and investigate its diversification, including divergence-time estimates and diversification rate shift analyses. METHODS: We performed the largest phylogenetic reconstruction for Philodendron to date, including 125 taxa with a combined dataset of three plastid regions (petD, rpl16, and trnK/matK). We estimated divergence times using Bayesian evolutionary analysis sampling trees and inferred shifts in diversification rates using Bayesian analysis of macroevolutionary mixtures. KEY RESULTS: We found that Philodendron, its three subgenera, and the closely related genus Adelonema are monophyletic. Within Philodendron subgenus Philodendron, 12 statistically well-supported clades are recognized. The genus Philodendron originated ~25 mya and a diversification rate upshift was detected at the origin of subgenus Philodendron ~12 mya. CONCLUSIONS: Philodendron is a species-rich Neotropical lineage that diverged from Adelonema during the late Oligocene. Within Philodendron, the three subgenera currently accepted are recovered in two lineages: one contains the subgenera Meconostigma and Pteromischum and the other contains subgenus Philodendron. The lineage containing subgenera Meconostigma and Pteromischum underwent a consistent diversification rate. By contrast, a diversification rate upshift occurred within subgenus Philodendron ~12 mya. This diversification rate upshift is associated with the species radiation of the most speciose subgenus within Philodendron. The sections accepted within subgenus Philodendron are not congruent with the clades recovered. Instead, the clades are geographically defined.

Recognition of the genus Thaumatophyllum Schott - formerly Philodendron subg. Meconostigma (Araceae) - based on molecular and morphological evidence.

Philodendron subgenus Meconostigma has been a well-circumscribed group since 1829. Members of this group are easily distinguished by diagnostic morphological characters as well as by a distinct ecology and geographical distribution. Based on molecular, morphological and cytological evidence, we propose the recognition of P. subg. Meconostigma as a distinct genus, Thaumatophyllum Schott. We also present the necessary new combinations, an emended key and some nomenclatural and taxonomic corrections regarding 21 names of Thaumatophyllum.

Unveiling the osmophores of Philodendron adamantinum (Araceae) as a means to understanding interactions with pollinators.

Background and Aims: Araceae species pollinated by nocturnal Cyclocephalini beetles attract their pollinators by inflorescence scents. In Philodendron , despite the intense odour, the osmophores exhibit no definite morphological identity, making them difficult to locate. This may explain why structural studies of the scent-releasing tissue are not available so far. Methods: Several approaches were employed for locating and understanding the osmophores of Philodendron adamantinum . A sensory test allowed other analyses to be restricted to fertile and sterile stamens as odour production sites. Stamens were studied under light and electron microscopy. Dynamic headspace and gas chromatography-mass spectrometry were used to collect and analyse scents from different zones of the inflorescence. Key Results: The epidermal cells of the distal portion of fertile stamens and staminodes are papillose and, similar to the parenchyma cells of this region, have dense cytoplasm and large nuclei. In these cells, the composition of organelles is compatible with secretory activity, especially the great number of mitochondria and plastids. In this portion, lipid droplets that are consumed concomitantly with the release of odour were observed. Quantitative scent analyses revealed that the scent, with a predominance of dihydro-ß-ionone, is mainly emitted by the fertile and sterile staminate zones of the spadix. An amorphous substance in the stomata pores indicates that the components are secreted and volatilized outside of the osmophore under thermogenic heat. Conclusions: Despite the difficulty in locating osmophores in the absence of morphological identity and inefficiency of neutral red staining, the osmophores of P. adamantinum have some features expected for these structures. The results indicate a functional link between thermogenesis and volatilization of osmophore secretions to produce olfactory signals for attracting specialized beetle pollinators. These first experimental data about the precise location of osmophores in Philodendron will stimulate studies in related species that will allow future comparison and the establishment of patterns of functional morphology.

Differential Accumulation of Volatile Organic Compounds by Leaves and Roots of Two Guianese Philodendron Species, P. fragrantissimum Kunth and P. melinonii Brongn.

Leaf and root essential oils of two closely related but ecologically distant Philodendron species were extracted in natural conditions in French Guiana and analysed by GC/MS to i) describe the blends of volatile organic compounds (VOCs) produced by those species and ii) analyse species and environment-based variations in extracts composition. A total of 135 VOCs were detected with a majority of aliphatic sesquiterpenes. P. fragrantissimum produced mainly ß-bisabolene (on average 29.12% of the extract) as well as α- and ß-selinene (14.52% and 17.50%, respectively) while in P. melinonii, four aliphatic sesquiterpenes could alternatively be the main component: (E)-ß-farnesene (up to 91.42% of the extract), germacrene-D (73.74%), ß-caryophyllene (51.63%) and trans-α-bergamotene (41.26%). A significant effect of species and organs on extracts composition was observed while the environment (sun exposure) only affected the relative proportions of monoterpenes and sesquiterpenes in roots of P. melinonii. These results are discussed in the light of the potential role of leaf and root terpenes in Philodendron species.

Plants of the Araceae family for malaria and related diseases: a review / Plantas da família Araceae para a malária e doenças relacionadas: uma revisão

ABSTRACTIn the current work we performed a review of the Araceae family species traditionally used to treat malaria and its symptoms. The aim is to reveal the large number of antimalarial Araceae species used worldwide and their great unexplored potential as sources of antimalarial natural products. The SciFinder Scholar, Scielo, PubMed, ScienceDirect and Google books search engines were consulted. Forty-three records of 36 species and 23 genera of Araceae used for malaria and symptoms treatment were found. The neotropical genera Philodendron Schott and Anthurium Schott were the best represented for the use in the treatment of malaria, fevers, liver problems and headaches. Leaves and tubers were the most used parts and decoction was the most common preparation method. The extracts of Araceae species inhibit the in vitro growth of the human malaria parasite, the Plasmodium falciparum Welch, and significant median inhibitory concentrations (IC50) for extracts of guaimbê-sulcado (Rhaphidophora decursiva (Roxb.) Schott), aninga (Montrichardia linifera (Arruda) Schott), Culcasia lancifolia N.E. Br. and forest anchomanes (Anchomanes difformis (Blume) Engl.) have been reported demonstrating the antimalarial and cytotoxicity potential of the extracts and sub-fractions. In the only report about the antimalarial components of this family, the neolignan polysyphorin and the benzoperoxide rhaphidecurperoxin presented strong in vitro inhibition of the D6 and W2 strains of Plasmodiumfalciparum (IC50 = 368-540 ng/mL). No live study about antimalarial activity in animal models has been conducted on a species of Araceae. More bioguided chemical composition studies about the in vitro and also thein vivo antimalarial activity of the Araceae are needed in order to enhance the knowledge about the antimalarial potential of this family.

RESUMONo presente trabalho realizamos uma revisão das espécies da família Araceae usadas para tratar malária e seus sintomas. O objetivo foi revelar o grande número de espécies da família usadas no mundo, assim como seu potencial como fontes de produtos naturais antimaláricos. Foram consultadas as plataformas de busca SciFinder Scholar, Scielo, PubMed, ScienceDirect e Google books. Encontramos quarenta e três registros de 36 espécies e 23 generos de Aráceas usadas para tratar malária e seus sintomas. Os generos neotropicais Philodendron Schott e Anthurium Schott foram os melhor representados, úteis para o tratamento da malária, febres, problemas hepáticos e dores de cabeça. Folhas e tubérculos foram as partes mais utilizadas, enquanto a decocção foi o método de preparo mais comum. Os extratos de espécies de Araceae inibem o crescimento in vitro do parasito da malária humana, Plasmodium falciparum Welch, e concentrações inibitórias medianas (CI50) significativas foram relatadas para extratos de guaimbê-sulcado (Rhaphidophora decursiva (Roxb.) Schott), aninga (Montrichardia linifera (Arruda) Schott), Culcasia lancifoliaN.E. Br. e anchomanes do mato (Anchomanes difformis (Blume) Engl.), demonstrando o potencial antimalárico e citotóxico de extratos e subfrações. No único relato sobre os componentes antimaláricos dessa família, a neolignana polisiforina e o benzoperóxido rafidecurperoxina apresentaram forte inibição das cepas D6 e W2 de Plasmodiumfalciparum in vitro (CI50 = 368-540 ng/mL). Nenhum estudo sobre a atividade antimalárica in vivo em modelo animal foi realizado com espécies da família Araceae. Mais trabalhos biomonitorados pela composição química sobre a atividade antimalárica in vitro, assim como estudos in vivo, são necessários para aprofundar os conhecimentos sobre potencial antimalárico da familia.

Estudo químico de duas plantas medicinais da amazônia: Philodendron scabrum k. Krause (araceae) e Vatairea guianensis aubl. (fabaceae) / Chemical study of two Amazonian medicinal plants: Philodendron scabrum K. Krause (Araceae) and Vatairea guianensis Aubl. (Fabaceae)

Este trabalho relata o estudo químico de duas plantas medicinais da Amazônia: Philodendron scabrum K. krause (Araceae) e Vatairea guianensis Aubl. (Fabaceae). As composições dos óleos essenciais dos cipós de P. scabrum e dos frutos de V. guianensis, respectivamente, foram analisadas em CG-DIC e CG-EM. Os constituintes majoritários dos cipós de P. scabrum foram óxido de cariofileno (19,42%), α-copaeno (16,08%) e ß-bisaboleno (10,01%); e nos frutos de V. guianensis foram o ácido (9Z)-octadecenoico (24,95%) e o ácido docosahexaenoico (24,17%). ß-sitosterol e o alquilresorcinol 1-hexadecanoil-2,6-dihidroxibenzeno foram isolados do extrato etanólico dos cipós de P. scabrum; e do extrato etanólico dos frutos de V. guianensis, foram isoladas as antraquinonas crisofanol e fisciona. As determinações estruturais foram baseadas em dados de RMN de ¹H e 13C. RMN, uni e bidimensional e comparação com dados da literatura.

This work describes the chemical study of two medicinal plants of the Amazon Philodendron scabrum K. Krause (Araceae) and Vatairea guianensis Aubl. (Fabaceae). Essential oils composition from stems of Philodendron scabrum K. Krause (Araceae) and fruits of Vatairea guianensis Aubl. (Fabaceae), respectively were analyzed in GC-FID and GC-MS. The major constituents from stems of P. scarabum were caryophyllene oxide (22.42%), α-copaene (16.08%) and ß-bisabolene (12.01%) and from fruits of V. guianensis were (9Z)-octadecenoic acid (24.95%) and docosahexenoic acid (24.17%). ß-sitosterol and alkylresorcinol 1-hexadecanoyl-2,6-dihydroxybenzene were isolated from ethanolic extracts from stems of P. scabrum and from ethanolic extracts from fruits of V. guianensis, the athraquinones chrysophanol and physcion were isolated. The structure of isolated compounds we determinate wered based on data from ¹H and 13C NMR, including two dimensional analyses and comparison with literature data.

Rotylenchulus reniformis on Greenhouse-grown Foliage Plants: Host Range and Sources of Inoculum.

Two sources of inoculum of reniform nematodes, Rotylenchulus reniformis, were identified for infestation of ornamental foliage plants in commercial greenhouses. These were water from a local canal system and rooted cuttings purchased from other sources. Eight ornamental plant species were identified as good hosts for the reniform nematode, with each species supporting a reniform population density equal to or greater than that supported by 'Rutgers' tomato and a reproduction factor of greater than 1.0. Nine other plant species were identified as poor hosts.