Comparative Flower and Inflorescence Organogenesis among Genera of Betulaceae: Implications for Phylogenetic Relationships

Betulaceae have simple flowers but complex inflorescences. Recent phylogenetic analyses using molecular data have produced robust phylogenetic trees of Betulaceae. In this study, we evaluated the phylogenetic value of comparative organogenetic data of reproductive organs in the context of molecular phylogenies. Flower and inflorescence developmental processes of 21 species from all six genera in Betulaceae were documented with scanning electron microscopy. In each pistillate cyme, there are one primary bract, two secondary bracts, and two or three flowers in the six genera; only in Alnus are there two tertiary bracts on the abaxial side. The pistillate flower of all genera but Alnus has tepal primordia. Two tepals stop developing early on, resulting in the lack of tepals in mature flowers of Betula; while the tepals are initiated from a common circular primordium at the base of pistil in Corylus, Ostryopsis, Carpinus, and Ostrya, and the developed tepals with irregular shape and unstable number of lobes are adnate to the top of the pistil. In staminate organogenesis, each cyme has one primary bract and three flowers in all genera; two secondary bracts are only present in Alnus, Betula, and Corylus. Staminate flowers have no tepals except in Alnus and Betula, and exhibit high variation in number of stamens among genera. The number of secondary and tertiary bracts in each pistillate and staminate cyme, as well as the presence of tepals in pistillate and staminate flowers was clarified in all genera. Micro-morphological characters were used to infer the phylogenetic relationships of genera and sections of Betulaceae. Our analyses support the division of two subfamilies: Betuloideae (Alnus and Betula) and Coryloideae (Corylus, Carpinus, Ostrya, and Ostryopsis), and three tribes: Betuleae (Alnus and Betula), Coryleae (Corylus), and Carpineae (Carpinus, Ostrya, and Ostryopsis). The results agree with those from molecular phylogenetic studies, and suggest that micro-morphological characters are phylogenetically informative in Betulaceae, and reproductive organs of Betulaceae have evolved in the direction of reduction in bracts and tepals.     

Diversity of natural products of the genera Curvularia and Bipolaris

Covering from 1963 to 2017.This review provides a summary of some secondary metabolites isolated from the genera Curvularia and Bipolaris from 1963 to 2017. The study has a broad objective. First to afford an overview of the structural diversity of these genera, classifying them depending on their chemical classes, highlighting individual examples of chemical structures. Also some information regarding their biological activities are presented. Several of the compounds reported here were isolated exclusively from endophytic and pathogenic strains in culture, while few from other sources such as sea Anemone and fish. Some secondary metabolites of the genus Curvularia and Bipolaris revealed a fascinating biological activities included: anti-malarial, anti-biofouling, anti-larval, anti-inflammatory, anti-oxidant, anti-bacterial, anti-fungal, anti-cancer, leishmanicidal and phytotoxicity. Herein, we presented a bibliography of the researches accomplished on the natural products of Curvularia and Bipolaris, which could help in the future prospecting of novel or new analogues of active metabolites from these two genera.     

Red Soils Harbor Diverse Culturable Actinomycetes That Are Promising Sources of Novel Secondary Metabolites

Red soils, which are widely distributed in tropical and subtropical regions of southern China, are characterized by low organic carbon, high content of iron oxides, and acidity and, hence, are likely to be ideal habitats for acidophilic actinomycetes. However, the diversity and biosynthetic potential of actinomycetes in such habitats are underexplored. Here, a total of 600 actinomycete strains were isolated from red soils collected in Jiangxi Province in southeast China. 16S rRNA gene sequence analysis revealed a high diversity of the isolates, which were distributed into 26 genera, 10 families, and 7 orders within the class Actinobacteria; these taxa contained at least 49 phylotypes that are likely to represent new species within 15 genera. The isolates showed good physiological potentials for biosynthesis and biocontrol. Chemical screening of 107 semirandomly selected isolates spanning 20 genera revealed the presence of at least 193 secondary metabolites from 52 isolates, of which 125 compounds from 39 isolates of 12 genera were putatively novel. Macrolides, polyethers, diketopiperazines, and siderophores accounted for most of the known compounds. The structures of six novel compounds were elucidated, two of which had a unique skeleton and represented characteristic secondary metabolites of a putative novel Streptomyces phylotype. These results demonstrate that red soils are rich reservoirs for diverse culturable actinomycetes, notably members of the families Streptomycetaceae, Pseudonocardiaceae, and Streptosporangiaceae, with the capacity to synthesize novel bioactive compounds.     

Phylogenetic reconstruction of character development in Physciaceae

Abstract:A cladistic analysis of the Physciaceae, based on morphological and chemical data, is presented. In the resulting phylogenetic reconstruction two major clades are formed, one containing the foliose genera (Anaptychia, Dirinaria, Heterodermia, Hyperphyscia, Physcia, Phaeophyscia,Physconia , Pyxine) and the fruticose Tornabea, and the other containing the remaining, mainly crustose genera. Rinodina appears as paraphyletic with representatives both at the base of the tree, at the same level as the two major clades and at the base of the crustose clade. Also Mobergia has a basal position. The characters used and their distribution in the phylogenetic trees are discussed as well as their significance for the identification of monophyletic groups. The history of the family is also briefly hinted at and characters of importance for the recognition of new genera are surveyed. Relevant publications and the variation in secondary chemistry are presented in tables.     

Phylogenetic relationships among Myrceugenia, Blepharocalyx, and Luma (Myrtaceae) based on paired-sites models and the secondary structures of ITS and ETS sequences

To establish relationships among the genera Blepharocalyx, Luma, and Myrceugenia, the phylogeny of tribe Myrteae was reconstructed based on secondary structures of the sequences of ITS (ITS1-5.8S-ITS2) and ETS regions from 93 taxa belonging to 29 genera. The DNA sequences were aligned according to their secondary structure and analysed with Bayesian inference (BI) using base substitution models for RNA, which can differentiate between the regions consisting of base pairs (helices) and unpaired bases (loops). The best-fit models were RNA7C for ITS and RNA7B for ETS, which differ in how they predict double substitutions and symmetry of the frequency of base pairs. The phylogenetic hypothesis was compared with results obtained using classical 4-state models, the results of maximum parsimony, and using sequence alignment without considering the secondary structure. Analyses show low support along the backbone of the consensus trees, those using substitution models of paired sites showing more highly supported derived clades than substitution models of independent sites. All tests were consistent and differed in the positioning of certain groups, but they also showed that Blepharocalyx, Luma, and Myrceugenia arise from three independent lineages that are not closely related. The substitution model for RNA shows that Luma is a monophyletic group and sister to the other genera of Myrteae, except for Myrtus communis. Myrceugenia appears as a monophyletic group, except for M. fernandeziana, which is related to Blepharocalyx, a genus that appears to be biphyletic.     

Recovery and Phylogenetic Diversity of Culturable Fungi Associated with Marine Sponges <Emphasis Type="Italic">Clathrina luteoculcitella</Emphasis> and <Emphasis Type="Italic">Holoxea</Emphasis> sp. in the South China Sea

Sponge-associated fungi represent an important source of marine natural products, but little is known about the fungal diversity and the relationship of sponge–fungal association, especially no research on the fungal diversity in the South China Sea sponge has been reported. In this study, a total of 111 cultivable fungi strains were isolated from two South China Sea sponges Clathrina luteoculcitella and Holoxea sp. using eight different media. Thirty-two independent representatives were selected for analysis of phylogenetic diversity according to ARDRA and morphological characteristics. The culturable fungal communities consisted of at least 17 genera within ten taxonomic orders of two phyla (nine orders of the phylum Ascomycota and one order of the phylum Basidiomycota) including some potential novel marine fungi. Particularly, eight genera of Apiospora, Botryosphaeria, Davidiella, Didymocrea, Lentomitella, Marasmius, Pestalotiopsis, and Rhizomucor were isolated from sponge for the first time. Sponge C. luteoculcitella has greater culturable fungal diversity than sponge Holoxea sp. Five genera of Aspergillus, Davidiella, Fusarium, Paecilomyces, and Penicillium were isolated from both sponges, while 12 genera of Apiospora, Botryosphaeria, Candida, Marasmius, Cladosporium, Didymocrea, Hypocrea, Lentomitella, Nigrospora, Pestalotiopsis, Rhizomucor, and Scopulariopsis were isolated from sponge C. luteoculcitella only. Order Eurotiales especially genera Penicillium, Aspergillus, and order Hypocreales represented the dominant culturable fungi in these two South China Sea sponges. Nigrospora oryzae strain PF18 isolated from sponge C. luteoculcitella showed a strong and broad spectrum antimicrobial activities suggesting the potential for antimicrobial compounds production.     

Seed lipids of the lythraceae

Fatty acid composition of seed lipids for 20 of the 26 genera in the Lythraceae and seed oil and protein content for nine genera are reported. The percent oil ranges from 2.7 to 34% of total weight and protein from 11.3 to 24.9%. Linoleic acid is the dominant fatty acid in seed lipids of all genera surveyed. Variations in pattern emphasize palmitic or oleic acid or both as second most abundant lipid component. There are three exceptions: in Diplusodon capric acid ranks second in abundance; in Adenaria lauric acid and oleic acid occur in approximately equal amounts as second most abundant fatty acid; in Decodon an unusual trienoic acid, previously reported only from the Compositae, is the main secondary component. Fatty acid composition of seeds in the genera is compared to that of the previously studied lythraceous genus Cuphea. Among all the genera, only Cuphea seed produces large quantities of lauric, capric, or caprylic acids, as well as a diversity of fatty acid patterns. No relationship between oil content or seed weight and habit is apparent in any genus studied, nor are differences in seed morphology reflected in composition of the seed lipids. The fatty acid patterns are judged evolutionarily conservative, with the strong exception of Cuphea, which remains unique in the Lythraceae and among all angiosperms for the diversity of patterns displayed.     

A molecular phylogenetic assessment of the advanced Asiatic and Malesian didymocarpoid Gesneriaceae with focus on non-monophyletic and monotypic genera

Based on a considerably enlarged sampling, a phylogenetic analysis of the largest group of didymocarpoid Gesneriaceae, the ??advanced Asiatic and Malesian genera??, was performed, covering all but 3 of the 60 genera presently recognised in this group (20 of these, mostly from China, are monotypic). The results suggest that no fewer than 17 out of the 57 genera examined are poly- (or rarely para-)phyletic. Highly polyphyletic are Briggsia, Chirita, Henckelia and Raphiocarpus. Only a dozen of the non-monotypic genera (including the three species-richest genera, Cyrtandra, Aeschynanthus and Agalmyla) are confirmed as monophyletic entities, though some exhibit considerable genetic variation. For eight genera, no statement can be made, as only one (of two or several) species was included in the analysis. For a dozen of the (particularly Chinese) monotypic genera a close relationship (or possible congenerity) with other genera was found. In China, only Allostigma, Cathayanthe, Conandron and Metapetrocosmea seem to have no strong affinities to other genera, indicating that they represent phylogenetically isolated lineages or represent remnants of previously larger and earlier diversified groups. The present study forms the foundation for targeted molecular, morphological and phytogeographic studies of the polyphyletic and monotypic genera and particular of clades of genera with interrelations uncovered here for the first time.     

A new species of Rhytidognathus (Carabidae,?Migadopini) from Argentina

The Migadopini are a small tribe of Carabidae with 47 species that occur in South America, Australia, and New Zealand, in the sub-Antarctic areas. In South America, most of the genera inhabit areas related to sub-Antartic Nothofagus forest except two monogeneric genera, the Ecuadorian genus Aquilex Moret and the Pampean genus Rhytidognathus Chaudoir. These two genera are geographically isolated from the remaining five South American genera. New material of Rhytidognathus from the northeast of Buenos Aires province and from Entre Ríos province permits establishing that the previous records of Rhytidognathus ovalis (Dejean) for Argentina were erroneous and that it belongs to a new species. Based on external morphological characters and from male and female genitalia we describe Rhytidognathus platensis as a new species. In this contribution we provide illustrations, keys, habitat characteristics and some biogeographic considerations on the distribution of Rhytidognathus.     

Patterns of chemical defense among Caribbean gorgonian corals: a preliminary survey

Ship-board assays employing the common Caribbean wrasse Thalassoma bifasdatum (Bloch) were undertaken to determine the palatability of food pellets coated with freshly-extracted, lipid-soluble metabolites of 37 types of Caribbean gorgonian corals representing at least 19 species from 11 genera. Extracts of 19 types (51%) were highly unpalatable (zero or one of five pellets eaten), four types (11%) were moderately unpalatable (two or three of five pellets eaten) and 14 (38%) were palatable (four or five of five pellets eaten) to fish in feeding assays. Gorgonians of the genera Pterogorgia (three types) and Eunicea (nine types) were consistently highly unpalatable, those of the genus Plexaurella (four types) were palatable and those of the genus Plexaura were most frequently palatable (six of eight types). Further assays of serial dilutions of extracts from seven representative, unpalatable types revealed that extracts inhibited fish feeding at pellet concentrations near or below the concentrations that metabolites occur in the gorgonian soft tissue. Extracts of Erythropodium caribaeorum (Duchassaing and Michelotti) and Pseudopterogorgia rigida (Bielschowsky) deterred fish feeding at pellet concentrations less than an order of magnitude lower than those found in the soft tissues of the corresponding gorgonians. Thin layer chromatographic analyses of extracts revealed the presence of lipid-soluble, secondary metabolites in a majority of the highly unpalatable extracts, although secondary metabolites were also present in a smaller percentage of palatable extracts. These data support the hypothesis that the soft tissues of many gorgonian corals contain lipid-soluble feeding deterrents which act as a defense against predation.     

Variation of secondary metabolite levels in maize seedling roots induced by inoculation with Azospirillum, Pseudomonas and Glomus consortium under field conditions

Background and aims

Many plant-beneficial microorganisms can influence secondary plant metabolism, but whether these effects add up when plants are co-inoculated is unclear. This issue was assessed, under field conditions, by comparing the early impacts of seed inoculation on secondary metabolite profiles of maize at current or reduced mineral fertilization levels.

Methods

Maize seeds were inoculated singly with selected strains from bacterial genera Pseudomonas and Azospirillum or mycorrhizal genus Glomus, or with these strains combined two by two or all three together. At 16?days, maize root methanolic extracts were analyzed by RP-HPLC and secondary metabolites (phenolics, flavonoids, xanthones, benzoxazionoids, etc.) identified by LC/MS.

Results

Inoculation did not impact on plant biomass but resulted in enhanced total root surface, total root volume and/or root number in certain inoculated treatments, at reduced fertilization. Inoculation led to qualitative and quantitative modifications of root secondary metabolites, particularly benzoxazinoids and diethylphthalate. These modifications depended on fertilization level and microorganism(s) inoculated. The three selected strains gave distinct results when used alone, but unexpectedly all microbial consortia gave somewhat similar results.

Conclusions

The early effects on maize secondary metabolism were not additive, as combining strains gave effects similar to those of Glomus alone. This is the first study demonstrating and analyzing inoculation effects on crop secondary metabolites in the field.     

Development of a phylogenetic model for the tribe Micrarctiini (Lepidoptera, Arctiidae) by the SYNAP method

A phylogenetic model for all the 18 genera of Micrarctiini (Lepidoptera, Arctiidae) of the World fauna is discussed. The SYNAP method was used for development of the model. For these purposes, 47 characters of the general appearance, male and female genitalia, and wing pattern were used. Based on these characteristics, an evolutionary trend from the plesiomorphic to apomorphic states was revealed. The genera Apantesis and Amurrhyparia, as well as Notarctia, differ from the other genera to the greatest extent. The other genera have formed two the main clades: Grammia + (Diacrisia + (Rhyparia + Rhyparioides)). Neoarctia + (Palearctia + Holoarctia + Chelis) and all the other genera have occupied separate positions. The latter group was divided into two clades: Ebertarctia + Tancrea + Divarctia with brachypterous females and Centrarctia + (Sibirarctia + (Micrarctia + Hyperborea)).     

Placing the origin of two species-rich genera in the late cretaceous with later species divergence in the tertiary: a phylogenetic, biogeographic and molecular dating analysis of Piper and Peperomia (Piperaceae)

Nearly all of the species diversity in Piperaceae is encompassed within Piper and Peperomia. Both genera are pan-tropical with areas of diversification in the Neotropics and Southeast Asia. Piperaceae are less diverse in Africa with only two native species of Piper. This study examines the distribution of both Piper and Peperomia with representative samples from the Neotropics, Asia, Pacific Islands, and Africa. Molecular dating is used to place an age for the crown clades of Piper and Peperomia as well as ages for diversification within the clades. Both genera have origins in the late Cretaceous, but species level diversification occurred much later in the Tertiary. Biogeography of both genera are correlated with paleoclimate evidence to better explain the distribution and diversification of these large genera.     

Biodiversity of Actinomycetes Associated with Caribbean Sponges and Their Potential for Natural Product Discovery

Marine actinomycetes provide a rich source of structurally unique and bioactive secondary metabolites. Numerous genera of marine actinomycetes have been isolated from marine sediments as well as several sponge species. In this study, 16 different species of Caribbean sponges were collected from four different locations in the coastal waters off Puerto Rico in order to examine diversity and bioactive metabolite production of marine actinomycetes in Caribbean sponges. Sediments were also collected from each location, in order to compare actinomycete communities between these two types of samples. A total of 180 actinomycetes were isolated and identified based on 16S rRNA gene analysis. Phylogenetic analysis revealed the presence of at least 14 new phylotypes belonging to the genera Micromonospora, Verruscosispora, Streptomyces, Salinospora, Solwaraspora, Microbacterium and Cellulosimicrobium. Seventy-eight of the isolates (19 from sediments and 59 from sponges) shared 100 % sequence identity with Micromonospora sp. R1. Despite having identical 16S rRNA sequences, the bioactivity of extracts and subsequent fractions generated from the fermentation of both sponge- and sediment-derived isolates identical to Micromonospora sp. R1 varied greatly, with a marked increase in antibiotic metabolite production in those isolates derived from sponges. These results indicate that the chemical profiles of isolates with high 16S rRNA sequence homology to known strains can be diverse and dependent on the source of isolation. In addition, seven previously reported dihydroquinones produced by five different Streptomyces strains have been purified and characterized from one Streptomyces sp. strain isolated in this study from the Caribbean sponge Agelas sceptrum.     

The tropical African legume Scorodophloeus clade includes two undescribed Hymenostegia segregate genera and Micklethwaitia,a rare,monospecific genus from Mozambique

Legume subfamily Caesalpinioideae accommodates approximately 2250 species in 171 genera which traditionally are placed in four tribes: Caesalpinieae, Cassieae, Cercideae and Detarieae. The monophyletic tribe Detarieae includes the Amherstieae subclade which contains about 55 genera. Our knowledge of the relationships among those genera is good in some cases but for many other genera phylogenetic relationships have been unclear. The non-monophyletic nature of at least two amherstioid genera, Cynometra and Hymenostegia has also complicated the picture. During the course of a multi-disciplinary study of Hymenostegia sensu lato, which includes phylogenetic analyses based on matK and trnL data, we have recovered the “Scorodophloeus clade”, an exclusively tropical African clade of four genera which includes the eponymous genus Scorodophloeus, two undescribed generic segregates of Hymenostegia sensu lato, and the previously unsampled rare monospecific genus Micklethwaitia from Mozambique. Zenkerella is suggested as a possible sister genus to the Scorodophloeus clade. A distribution map is presented of the seven species that belong to the Scorodophloeus clade.     

The flagellates of the termite Hodotermopsis sjoestedti with special reference to Hoplonympha,Holomastigotes and Trichomonoides trypanoides n. comb.

The termite Hodotermopsis sjoestedti harbours a symbiotic fauna of protists comprising at least 11 genera and a much larger number of species. Two oxymonad genera, Pyrsonympha and Dinenympha, are mixed with nine parabasalid genera, two trichomonads, Trichomitopsis termopsidis and Trichomonoides trypanoides n. comb., four spirotrichonymphid genera/species: Spirotrichonympha, Microjoenia, Holomastigotes lanceolata n. sp., Holomastigotes elongatum and three trichonymphid genera/species; Hoplonympha natator, Eucomonympha, Trichonympha. Hoplonympha natator has two anterior symmetrical bundles of ∼60 basal bodies/flagella separated by two parabasal plates. The cell surface is crenelated and covered by Fusiformis bacteria which adhere by a thin ridge of cell-coat. Phagocytosis and digestion of Fusiformis appear likely from electron microscopy observations. Holomastigotes lanceolata has five dexiotropic flagellar lines in the anterior part and only two in the posterior part, one striated root attached to the proximal section of the basal bodies, a striated lamina and a complete axostyle. Trichomonoides trypanoides corresponds to Trichomonas trypanoides Duboscq and Grassé, 1924; it has four anterior flagella and an enlarged recurrent flagellum which is similar to that of Pentatrichomonoides scroa. These results are in agreement with the molecular phylogeny study of Hodotermopsis sjoestedti flagellates by Ohkuma et al. (J. Eukaryot. Microbiol. 47 (2000) 249) who found a small subunit ribosomal RNA sequence HsL8 grouping with that of Pentatrichomonoides scroa.     

Diversity of the Most Commonly Reported Facultative Symbionts in Two Closely-Related Aphids with Different Host Ranges

Richness and abundance of facultative symbionts vary strongly with aphid species and genotype, symbiont strain, host plant, biogeography, and a number of abiotic factors. Despite indications that aphids in the same ecological niche show similar levels of facultative symbiont richness, existing reports do not consider the potential role of host plants on aphid microbial community. Little is known about how oligophagy and polyphagy may be influenced by secondary symbiont distribution, mainly because studies on secondary symbiont diversity are biased towards polyphagous aphids from the Northern Hemisphere. Here, we demonstrate the richness and abundance of the most common aphid-associated facultative symbionts in two tropical aphid species, the oligophagous Aphis (Toxoptera) citricidus (Kirkaldy) (Hemiptera: Aphididae) and the polyphagous Aphis aurantii (Boyer de Fonscolombe) (Hemiptera: Aphididae). Aphis citricidus is restricted to Citrus sp. host plants and closely related genera, whereas A. aurantii successfully exploits a wide variety of host plants from different families. Both were collected in the same ecological niche and our data basically indicated the same richness of secondary symbionts, but the abundance at which secondary symbionts occurred was very distinct between the two species. Spiroplasma was the most abundant facultative symbiont associated with A. citricidus and A. aurantii in the ecological niche studied. Single and multiple secondary symbiont infections were observed, but diversity of multiple infections was particularly high in A. citricidus. We discuss our findings and suggest hypotheses to explain causes and consequences of the differences in secondary symbiont diversity observed between these two aphid species.     

The Genera of the Subfamily Heteroderinae (Nematoda: Tylenchoidea) with a Description of Two New Genera

The family Heteroderidae, its two subfamilies Heteroderinae and Meloidogyninae and the nominal genera of Heteroderinae (Heterodera Schmidt, 1871; Meloidodera Chitwood, Hannon &Esser, 1956; and Cryphodera Colbran, 1966) are rediagnosed. Meloidoderita Pogosyan, 1966 is considered a genus inquirenda. Two new genera from southern California are described in the subfamily Heteroderinae. A key to the genera, illustrations and a phylogeny of the Heteroderinae are proposed.     

Cladistic analysis of Taxaceae s. l.

Taxaceae s. l. is a wider concept of classification treating five genera of Taxaceae s. str. and Cephalotaxus together. Cephalotaxus is morphologically very similar to the five genera of Taxaceae s. str. Various models of classification for six genera have already been published. However, the phylogenetic position and genuine relationships of these genera and species are still confusing. A cladistic analysis of Taxaceae s. l. has been carried out to resolve the problem existing in their phylogeny and to provide a new approach regarding the relationships of these six genera. Parsimony analyses were based on 28 characters and eight genera including two outgroups Agathis and Sciadopitys. The most parsimonious tree retained with branch length 38 and 194 rearrangement trials. Consistency index was 0.68 and retention index was 0.66. Principally, two main clades were found: one represented by Austrotaxus forming the base of the tree and another by the remaining five genera. Taxus + Pseudotaxus clade split after Austrotaxus, and Cephalotaxus was sister to Torreya + Amentotaxus clade. Taxus + Pseudotaxus clade was supported by the highest bootstrap value. Finally, cladistic analysis does not support existence of Cephalotaxaceae. Therefore, it would be better to classify Cephalotaxus within Taxaceae s. l. with the other five genera.