Taxonomy of Gundlachia (Compositae: Astereae)

Gundlachia, a genus of shrubs occurring in the Caribbean islands, is treated as comprising two species, one of which has six varieties. Five new combinations are made: Gundlachia corymbosa var. apiculata (Britton & S. F. Blake) M. A. Lane, G. corymbosa var. compacta (Urb. & Ekman) M. A. Lane, G. corymbosa var. cubana (Britton & S. F. Blake) M. A. Lane, G. corymbosa var. foliosa (Britton & S. F. Blake) M. A. Lane, and G. corymbosa var. ocoana (Urb. & Ekman) M. A. Lane. Gundlachia is probably most closely related to Gymnosperma.     

New taxa and combinations in Malvastrum A. Gray (Malvaceae: Malveae)

The genusMalvastrum A. Gray is interpreted to include 22 taxa in 14 species. Seven taxa are here described as new, namely:M. americanum var.stellatum,M. tomentosum subsp.pautense,M. bicuspidatum subsp.campanulatum,M. bicuspidatum subsp.oaxacanum, M. bicuspidatum subsp.tumidum var.tumidum, M. bicuspidatum subsp.tumidum var.glabrum, andM. coromandelianum subsp.fryxellii. In addition, two new combinations are proposed, namely:M. tomentosum andM. coromandelianum subsp.capitato-spicatum.     

Mycopteris,a new neotropical genus of grammitid ferns (Polypodiaceae)

Mycopteris, a new genus of grammitid ferns, is described and combinations are made for the species that belong to it. Mycopteris is diagnosed by castaneous rhizome scales with turgid cells, usually pectinate laminae, blackish petioles and rachises, blackish pinna costae and veins, reddish setae, cretaceous hydathodes, glabrous sporangia, and the presence of Acrospermum ascomes. It is entirely neotropical, ranging from Mexico east into the West Indies and south to Bolivia. Mycopteris is one of two genera of grammitid ferns that are consistently associated with Acrospermum, an epibiotic ascomycete that produces black clavate fruiting bodies. Seventeen species of Mycopteris are recognized here, including one new species (M. longipilosa) and one elevated from the rank of variety to species (M. costaricensis). The following additional combinations are made here: M. alsopteris, M. amphidasyon, M. attenuatissima, M. cretata, M. grata, M. leucolepis, M. leucostica, M. longicaulis, M. pirrensis, M. praeceps, M. semihirsuta, M. steyermarkii, M. subtilis, M. taxifolia, and M. zeledoniana. Lectotypes are chosen for Ctenopteris leucosticta, Polypodium amphidasyon, and Polypodium pectinatum var. hispidum. For each accepted species, full synonymy and geographical range are provided. Taxonomic discussion is provided for species not widely recognized in previous treatments.     

New species of Solanum section Geminata (Solanaceae) from South America

Fourteen new species ofSolanum sectionGeminata are described and illustrated. Eight of these,S. erosomarginatum, S. foetens, S. lasiocladum, S. lucens, S. ombrophilum, S. tanysepalum, S. tenuiflagellatum, andS. turgidum are from Venezuela.Solanum cucullatum andS. bellum are from Ecuador,S. abitaguense from Ecuador and northeastern Peru,S. amnicola andS. yanamonense from eastern Peru, andS. mapiricum from eastern Bolivia. Relationships of each of the species to others in its geographical area are discussed. Chromosome numbers are reported for ten of these new species.     

Toward a census of genus Mimosa (Mimosaceae) in the Americas: a new species from Mexico (Baja California Sur) and two from planaltine Brazil (Goiás, Minas Gerais)

Three new species of Mimosa are described: M. (sect. Batocaulon) epitropica Barneby & León de la Luz from Mexico (Baja California Sur); and two from planaltine Brazil, M. (sect. Habbasia) bispiculata Barneby and M. (sect. Mimosa) demissa Barneby. The affinity of each is discussed, and all are illustrated.     

Sphaeromeria,a genus closer to Artemisia than to Tanacetum (Asteraceae: Anthemideae)

A new species,Sphaeromeria ruthiae, from Zion National Park, and three new combinations,S. martirensis,S. compacta, andS. potentilloides var.nitrophila, are presented. Morphological and anatomical evidence is used to support the recognition ofSphaeromeria as distinct fromTanacetum.     

Four new diplostemonous species of mimosa (Mimosaceae) from Paraguay and eastern Bolivia

Four species of Mimosa, M. aureliana, M. chacoënsis, and M. tobatiensis known only from eastern Paraguay, and M. castanoclada known from northwestern Paraguay and eastern Bolivia, are described, figured, and compared with near kindred.     

Five new species of Solanum section Geminata (Solanaceae) from South America

Five new species of South AmericanSolanum are described:S. morii from French Guiana,S. superbum andS. tumescens from Bolivia,S. platycypellon from southern Bolivia and northern Argentina andS. gertii from southeastern Brazil. An illustration and distribution map for each species is provided and relationships to close relatives are discussed.     

Dimeric bisbenzimidazoles: Cytotoxicity and effects on DNA methylation in normal and cancer human cells

Cancer cells are characterized by hypermethylation of the promoter regions of tumor suppressor genes. DNA methyltransferase inhibitors reactivate the genes, pointing to DNA methyltransferases as potential targets for anticancer therapy. Dimeric bisbenzimidazoles varying in the length of an oligomeric linker between two bisbenzimidazole residues (DB(n), where n is the number of methylene groups in the linker) were earlier shown to efficiently inhibit methylation of DNA duplexes by murine DNA methyltransferase Dnmt3a. Here, some of the compounds were tested for cytotoxicity, cell penetration, and effect on genomic DNA methylation in F-977 fetal lung fibroblasts and HeLa cervical cancer cells. Within the 0–60 μM concentration range, only DB(11) exerted a significant toxic effect on normal cells, whereas the effects of DB(n) on cancer cells were not significant. DB(1) and DB(3) slightly stimulated proliferation of HeLa and F-977 cells, respectively. DB(1) and DB(3) penetrated into the nuclei of HeLa and F-977 cells and accumulated predominantly in or near the nucleolus, while DB(11) was incapable of nuclear penetration. HeLa cells incubated with 26 μM DB(1) or DB(3) displayed a decrease in methylation of the 18S rRNA gene, which was in the regions of predominant accumulation of DB(1) and DB(3). The same DB(3) concentration exerted a similar effect on F-977 cells. However, the overall genomic DNA methylation level remained unchanged in both of the cell lines. The results indicated that DB(n)-type compounds can be used to demethylate certain genes and are thereby promising as potential anticancer agents.     

New species and new combinations in the sematophyllum subpinnatum complex (Sematophyllaceae)

Three new tropical American species ofSematophyllum are described with relatively broad leaves and short upper leaf cells:S. cubense, S. cataractae, andS. oedophysidium. The Central AmericaS. apaloblastum andS. barnesii are new combinations.Sematophyllum galipense, S. amnigenum, andS. cochleatum are briefly discussed.     

New taxa and combinations in Siphonoglossa (Acanthaceae)

As presently known, the genusSiphonoglossa can be divided into two “subgenera,” one of which is here divided into two sections,Pentaloba andSiphonoglossa. Two new species are described from a locality in Durango, Mexico :S. durangensis in sect.Siphonoglossa andS. linearifolia in sect.Pentaloba. Three other species are transferred intoSiphonoglossa:S. canbyi from northeastern Mexico;S. buchii from Haiti and the Dominican Republic andS. incerta from southern Baja California, Mexico.     

Combination of 1,4-naphthoquinone with benzothiazoles had selective algicidal effects against harmful algae

A series of naphthoquinone-benzothiazole conjugates were synthesized as algicides, and their efficacies against harmful algal blooming species, such as Chattonella marina, Heterosigma akashiwo and Cochlodinium polykrikoides, were examined. The introduction of substituted benzothiazole at the C2 position of 1,4-naphthoquinone (compounds 1–9) resulted in higher algicidal activity against C. polykrikoides than the C6 conjugates (compounds 10–20). On the other hand, of the C6 conjugates, compounds 11 and 12 exhibited better algicidal activity against H. akashiwo, C. marina, and C. polykrikoides than the C2 conjugates. Further structure-activity analysis indicated that a replacement of the methoxy groups with hydroxyl groups (compounds 21–26) decreased the algicidal activity significantly. Among the various synthetic naphthoquinonebezothiazole conjugates tested, compound 12 was found to affect the most significant decrease in the level of C. polykrikoides growth, with an IC₅₀ of 0.19 μM. Compound 11 was found to be the most potent inhibitor against H. akashiwo and C. polykrikoides, with IC₅₀ values of 0.32 and 0.12 μM, respectively. Overall, these results highlight a possible method for controlling and inhibiting red tide forming algae using NQ derivatives.     

Miscellaneous mistletoe notes, 1–9

Three new species,Cladocolea biflora Kuijt,Struthanthus condensatus Kuijt, andS. lojae Kuijt are described and six new combinations,Cladocolea diversifolia (Benth.) Kuijt,C. lenticellata (Diels) Kuijt,Dendrophthora virgata (Trel.) Kuijt,Korthalsella chilensis (Hook. & Arn.) Kuijt,Phthirusa retroflexa (Ruiz & Pavon) Kuijt, andStruthanthus flexilis (Rusby) Kuijt are proposed. Nomenclature of two more neotropical Loranthaceae,Psittacanthus ramiflorus (DC.) G. Don andStruthanthus interruptus (H.B.K.) Blume is revised.     

Novelties in Serjania (Sapindaceae)

Three new species ofSerjania (S. magnistipulata andS. mori from Bahía, Brazil andS. schunkei from Perú) are described, discussed, and illustrated.     

Four new species of Smilax (Smilacaceae) from southeastern Asia

Described as new areSmilax biumbellata of the affinity ofS. nervomarginata,S. siamensis of the affinity of 5.perfoliata, and two others inSmilax sect.Macranthae:S. inversa andS. pachysandroides.Smilax inversa (characterized by strongly deflexed leaves and inflorescences on zigzag stems) andS. pachysandroides (with subsessile leaves on low simple stems) show no close resemblance to any previously known species of the section.     

Development of somatic hybrids Solanum × michoacanum Bitter. (Rydb.) (+) S. tuberosum L. and autofused 4x S. × michoacanum plants as potential sources of late blight resistance for potato breeding

Key message

Phytophthora infestans resistant somatic hybrids of S. × michoacanum (+) S. tuberosum and autofused 4 x S. × michoacanum were obtained. Our material is promising to introgress resistance from S. × michoacanum into cultivated potato background.

Abstract

Solanum × michoacanum (Bitter.) Rydb. (mch) is a wild diploid (2n = 2x = 24) potato species derived from spontaneous cross of S. bulbocastanum and S. pinnatisectum. This hybrid is a 1 EBN (endosperm balance number) species and can cross effectively only with other 1 EBN species. Plants of mch are resistant to Phytophthora infestans (Mont) de Bary. To introgress late blight resistance genes from mch into S. tuberosum (tbr), genepool somatic hybridization between mch and susceptible diploid potato clones (2n = 2x = 24) or potato cultivar Rywal (2n = 4x = 48) was performed. In total 18,775 calli were obtained from postfusion products from which 1,482 formed shoots. The Simple Sequence Repeat (SSR), Cleaved Amplified Polymorphic Sequences (CAPS) and Random Amplified Polymorphic DNA (RAPD) analyses confirmed hybrid nature of 228 plants and 116 autofused 4x mch. After evaluation of morphological features, flowering, pollen stainability, tuberization and ploidy level, 118 somatic hybrids and 116 autofused 4x mch were tested for late blight resistance using the detached leaf assay. After two seasons of testing three somatic hybrids and 109 4x mch were resistant. Resistant forms have adequate pollen stainability for use in crossing programme and are a promising material useful for introgression resistance from mch into the cultivated potato background.     

The subdivisions of Magnistipula Engl. (Chrysobalanaceae)

A conspectus of the subgenera and sections ofMagnistipula is provided. Of the two subgenera occurring on the African mainland, subgenusMagnistipula is divided into the sectionsMagnistipula,Animalculum andPeregrinator, whereas subgen.Pellegriniella is monotypic. A Malagasy subgenus,Tolmiella, is new; its two species,M. cerebriformis andM. tamenaka, are transferred fromHirtella.     

New names,combinations, and lectotypifications in Heterotheca (Compositae: Astereae)

The following new names and combinations are proposed:Heterotheca barbata (Rydb.) Semple,H. horrida subsp.cinerascens (S. F. Blake) Semple,H. fulcrata vararizonica Semple,H. fulcrata var.senilis (Wooton & Standley) Semple,H. oregona var.compacta (Keck) Semple,H. oregona var.rudis (Greene) Semple,H. oregona var.scaberrima (A. Gray) Semple,H. pumila (Greene) Semple,H. villosa var.pedunculata (Greene) V. Harms ex Semple, andH. zionensis Semple. The following chromosome numbers are reported for the first time:H. fulcrata var.arizonica, 2n=9 _II ;H. horrida subsp.cinerascens, 2n=18 _II ;H. pumila, 2n=9 _II ,2n=18 _II ;H. zionensis, 2n=9 _II .