Presence Of Prickles Research Articles

Comparative Morphology, Anatomy and Phytochemistry of Cyrtosperma senegalense (Schott) Engl. and Alocasia macrorrhizos L. (Araceae)

Morphological, anatomical and epidermal studies were carried out on two species of Araceae, Cyrtosperma senegalense (Schott) Engl. and Alocasia macrorrhizos L. to investigate the taxonomic value of their similarities and differences. Morphological features were visually observed. Fresh specimens were dehydrated, wax embedded, mounted, microscopically observed and micrographed. Basic similarities were found in their leaf shape, venation, inflorescence and spathe, seeded fruits, scattered vascular bundles, possession of aerenchyma, and presence of stomata on the abaxial and adaxial leaf surfaces. Conversely, the presence of prickles and sparseness of raphide idioblasts containing a raphide bundle each in C. senegalense distinguishes it from A. macrorrhizos which has abundant raphides. Phytochemical screening shows differences in their alkaloids, saponin, triterpenoids, steroids and glycosides contents. Though these preliminary studies yielded data that revealed their relationship and phytochemistry, further investigations of their cytology using electron microscopy and molecular biology are needed for more diagnostic data to distinguish them from each other and add more incite to their potential in drug discovery.

Comparative transcriptome analysis reveals hormone, transcriptional and epigenetic regulation involved in prickle formation in Zanthoxylum armatum

Zanthoxylum armatum is an evergreen plant with high economical and medicinal values. The presence of prickles on stems and leaves is undesirable for them make picking difficult. To date, little is known of prickle formation in Z. armatum. Herein, the morphological and molecular features of prickle initiation in prickless (WC) and three types of prickly Z. armatum were characterized. Compared to WC, the levels of cytokinin and auxin were increased, while GA and JA declined in prickly Z. armatum. Transcriptome analysis identified 6258 differentially expressed genes (DEGs) between prickless and prickly Z. armatum. Among them, several DEGs related to hormone metabolism and signaling, including LOG7, CKX3, AHK1, three DELLAs, six JAZs and TIR1, were candidate genes involved in prickle formation. Transcription factors associated with prickle formation were screened, including MYB6-1/MYB6-2, WER, GL3-2, SPL4/5, SOC1, and SCL32. Of them, MYB6-1 and WER might negatively regulate prickles initiation via interacting with GL3-2. Additionally, the histone acetylation and DNA methylation levels, the transcripts of histone acetyltransferase/deacetylase and DNA methyltransferases showed significant differences between prickless and prickly plants, indicating their involvements in prickle initiation. These findings illustrate the regulation of prickle formation might be mediated by phytohormones (especially cytokinin), transcription factors and epigenetic modifications in Z. armatum.

Leaf micromorphology and anatomy in the tribe Aristideae (Poaceae) in Iran and its systematic implications

The present study investigated the leaf anatomy of 12 species belonging to the genera Aristida and Stipagrostis of the Aristideae tribe in Iran. Scanning electron microscopy (SEM) and light microscopy (LM) were used to observe the epidermal characteristics and transverse sections of the leaves to assess taxonomic applications of these traits. The main distinguishing traits of the species included: the presence of prickles, macrohairs and microhairs, papillae and type of wax, adaxial ribs, number of bulliform cells, number of sclerenchymatous layers and shape of silica bodies. When constructing the phenogram of Aristideae using WARD’s method and based on the 7 qualitative and 18 quantitative anatomical traits showed four taxonomic-anatomic clades with a cophenetic correlation coefficient of 1.75. Kranz anatomy in S. raddiana differed from the one seen inS. paradisea. The presence of papillae and lack of macrohairs on the leaf epidermis in S. karelinii distinguished it from S. pennata. By present findings the placement of A. coerulescens as a variety of A. adscensionis has not been ascertained. An identification key is providedbased on anatomical traits.The anatomical features of the leaves were proved to be useful for species delimitation and as a supplementary tool for identifying taxa and macromorphological traits.

Evaluation of Advanced Backcrosses of Eggplant with Solanum elaeagnifolium Introgressions under Low N Conditions

Selection and breeding of eggplant (Solanum melongena) materials with good performance under low nitrogen (N) fertilization inputs is a major breeding objective to reduce environmental degradation, risks for human health, and production costs. Solanum elaeagnifolium, an eggplant wild relative, is a potential source of variation for introgression breeding in eggplant. We evaluated 24 plant, fruit, and composition traits in a set of genotyped advanced backcrosses (BC2 and BC3) of eggplant with S. elaeagnifolium introgressions under low N conditions. Significant differences were found between the two parents for most traits, and a wide phenotypic diversity was observed in the advanced backcrosses, with some individuals with a much higher yield, nitrogen use efficiency (NUE), and phenolics content than the S. melongena parent. In general, the lower the proportion of S. elaeagnifolium genome introgressed in the advanced backcrosses, the higher was the general phenotypic resemblance to S. melongena. Putative QTLs were detected for stem diameter (pd4), presence of prickles in stem (ps6), leaf (pl6) and fruit calyx (pc6), fruit width (fw7), chlorogenic acid content (cg5), total phenolic acid peaks area (ph6), chlorogenic acid peak area (ca1), and phenolic acids pattern (cp1). Our results reveal that introgression breeding of eggplant with S. elaeagnifolium has a great interest for eggplant breeding, particularly for adaptation to low N conditions. These materials can potentially contribute to the development of improved eggplant varieties for a more sustainable agriculture.

Prickle morphogenesis in rose is coupled with secondary metabolite accumulation and governed by canonical MBW transcriptional complex.

Rose is an economically important flowering plant that holds an essential place in cut flower, medicinal, and aromatic industries. The presence of prickles, epidermal outgrowths resembling trichomes, on rose is highly undesirable as these make harvesting and transportation difficult. Attempts were made for generating rose varieties lacking prickles via breeding and natural selections; however, these approaches obtained only chimeric and genetically unstable prickle‐less mutants. The alternative way to get rid of prickles is via genetic manipulations, but the molecular mechanisms of prickle initiation and development in rose are almost unexplored. Therefore, the present study was carried out to understand the morphological, molecular, and correlated metabolic changes underlining prickle morphogenesis in a prickle‐bearing Rosa hybrida L. cv. “First Red (FR)”. The histological and metabolomic analyses at three distinct stages of the prickle morphogenesis, namely, emerging tiny initiating prickles, partially greenish soft prickles, and brownish hard prickles, demonstrated a gradually increasing deposition of phenolic compounds and lignification with development. Corresponding RNAseq analysis revealed an upregulation of the genes involved in secondary metabolism, especially in the phenylpropanoid biosynthetic pathway. A set of genes encoding a transcriptional network similar to the one regulating epidermal cell differentiation leading to phenylpropanoid accumulation and trichome development, was also upregulated. Differential expression of this transcriptional network in prickle‐less R. hybrida L. cv. “Himalayan Wonder” compared to prickly FR plants substantiated its involvement in prickle morphogenesis. The results collectively supported the proposition that prickles are evolved from trichomes and provided molecular clues towards engineering prickle‐less roses.Significance statementPrickles, the vasculature less epidermal outgrowths resembling trichomes, are defense organs protecting plants against herbivory. Despite biological significance, the mechanism of prickle morphogenesis remains obscure. Here, we show that like trichomes, prickles accumulate secondary metabolites, especially lignin and flavonoids, during morphogenesis. Cognate transcriptome analysis demonstrated that upregulation of a hormone‐regulated transcriptional activation–inhibition network, known to govern trichome morphogenesis, likely triggers the differentiation of epidermal cells to outgrow into prickle.

Molecular characterization of a species in the genus Rubus in Boyacá, Colombia

Abstract Colombia is home to blackberry genetic resources which present a morphological diversity. The relevant characteristics related to its diversity are the presence of prickles, the shape of its leaves, the number and color of its fruits, and its enormous agro-industrial potential due bioactive compounds such as polyphenols. These plants can grow between 1,700 and 3,400 m asl and are cultivated in the central region of the country. The study evaluated 13 wild and cultivated plants from the genus Rubus. A molecular characterization was carried out using 16 SSR microsatellite markers, all of which produced positive amplification generating 23 loci and 26 alleles. The AMOVA indicated a molecular genetic differentiation of 23% between the groups which corresponded to the geographic location of the sample. The greatest contribution to variance is found within the groups (76%), possibly because each of them is composed of different cultivated species and wild relatives of the genus Rubus. This suggests that the grouping of the genotypes studied doesn’t necessarily correspond to geographical origin. However, the findings show high genetic variation, with an Fst value of 0.27. This may be useful in breeding programs where genetic diversity, morphological characteristics of the fruits, and the molecular identification of the fruits are taken into account.

Genome-Wide Association Study (GWAS) for Examining the Genomics Controlling Prickle Production in Red Raspberry (Rubus idaeus L.)

Red raspberry (Rubus idaeus L.) is an expanding high-value berry crop worldwide. The presence of prickles, outgrowths of epidermal tissues lacking vasculature, on the canes, petioles, and undersides of leaves complicates both field management and harvest. The utilization of cultivars with fewer prickles or prickle-free canes simplifies production. A previously generated population segregating for prickles utilizing the s locus between the prickle-free cultivar Joan J (ss) and the prickled cultivar Caroline (Ss) was analyzed to identify the genomic region associated with prickle development in red raspberry. Genotype by sequencing (GBS) was combined with a genome-wide association study (GWAS) using fixed and random model circulating probability unification (FarmCPU) to analyze 8474 single nucleotide polymorphisms (SNPs) and identify significant markers associated with the prickle-free trait. A total of four SNPs were identified on chromosome 4 that were associated with the phenotype and were located near or in annotated genes. This study demonstrates how association genetics can be used to decipher the genetic control of important horticultural traits in Rubus, and provides valuable information about the genomic region and potential genes underlying the prickle-free trait.

RNA-Seq Analysis of Prickled and Prickle-Free Epidermis Provides Insight into the Genetics of Prickle Development in Red Raspberry (Rubus ideaus L.)

Red raspberry (Rubus idaeus L.) is a globally commercialized specialty crop with growing demand worldwide. The presence of prickles on the stems, petioles and undersides of the leaves complicates both the field management and harvesting of raspberries. An RNA sequencing analysis was used to identify differentially expressed genes in the epidermal tissue of prickled “Caroline” and prickle-free “Joan J.” and their segregating progeny. Expression patterns of differentially expressed genes (DEGs) in prickle-free plants revealed the downregulation of some vital development-related transcription factors (TFs), including a MIXTA-like R2R3-MYB family member; MADS-box; APETALA2/ETHYLENE RESPONSIVE FACTOR (AP2/ERF) and NAM, ATAF1/2 and CUC2 (NAC) in prickle-free epidermis tissue. The downregulation of these TFs was confirmed by qRT-PCR analysis, indicating a key regulatory role in prickle development. This study adds to the understanding of prickle development mechanisms in red raspberries needed for utilizing genetic engineering strategies for developing prickle-free raspberry cultivars and, possibly, other Rubus species, such as blackberry (Rubus sp.) and black raspberry (R. occidentalis L.).

Comparative population genomics dissects the genetic basis of seven domestication traits in jujube

Jujube (Ziziphus jujuba Mill.) is an important perennial fruit tree with a range of interesting horticultural traits. It was domesticated from wild jujube (Ziziphus acidojujuba), but the genomic variation dynamics and genetic changes underlying its horticultural traits during domestication are poorly understood. Here, we report a comprehensive genome variation map based on the resequencing of 350 accessions, including wild, semi-wild and cultivated jujube plants, at a >15× depth. Using the combination of a genome-wide association study (GWAS) and selective sweep analysis, we identified several candidate genes potentially involved in regulating seven domestication traits in jujube. For fruit shape and kernel shape, we integrated the GWAS approach with transcriptome profiling data, expression analysis and the transgenic validation of a candidate gene to identify a causal gene, ZjFS3, which encodes an ethylene-responsive transcription factor. Similarly, we identified a candidate gene for bearing-shoot length and the number of leaves per bearing shoot and two candidate genes for the seed-setting rate using GWAS. In the selective sweep analysis, we also discovered several putative genes for the presence of prickles on bearing shoots and the postharvest shelf life of fleshy fruits. This study outlines the genetic basis of jujube domestication and evolution and provides a rich genomic resource for mining other horticulturally important genes in jujube.

Morphological Characterization of Prickled and Prickle-free Rubus Using Scanning Electron Microscopy

Caneberry crops (raspberry and blackberry) are globally commercialized specialty crops with a high fresh market value. Field management of canes and harvesting of fruits can be complicated by the presence of prickles (the botanically accurate term rather than spines or thorns) on the stems, petioles, and underside of the leaves. Both field management and fruit harvesting could be simplified by the development of cultivars with prickle-free canes. Scanning electron microscopy (SEM) was used to analyze and compare prickle development in different Rubus species. Comparisons were made between prickled vs. prickle-free red raspberry (Rubus idaeus L.), black raspberry (Rubus occidentalis L.), blackberry (Rubus hybrid), complex hybrid with purple fruit (R. occidentalis × R. idaeus), and the hairy and prickled wineberry (Rubus phoenicolasius Maxim). Samples from stems and leaves with petioles attached were used for imaging. There were distinct differences between prickled vs. prickle-free phenotypes in each species. The images of prickle development suggest that prickles either develop directly from glandular trichomes (in red raspberry and wineberry) or that the signal originates from glandular trichomes (in blackberry). Black raspberry prickle development was similar to that of blackberry, suggesting that prickles developed after a developmental signal from glandular trichomes rather than as a direct development from glandular trichomes. The prickle development in the purple hybrid was unique in the presence of one-sided lumps in the trichomes, which has not been seen in any other Rubus species to date; however, both prickled and prickle-free plants exhibited simple nonglandular trichomes. Unlike previous studies, an increase in the number of simple trichomes was not specific to prickle-free plants, but rather variability among the different genotypes was observed. This study adds to the basic understanding of prickle development in the genus Rubus as a first step in the development of prickle-free versions of important cultivars through gene-editing procedures for improving the ease of field management and harvesting.

Zamia brasiliensis, a new species of Zamia (Zamiaceae, Cycadales) from Mato Grosso and Rondônia, Brazil

Zamia brasiliensis Calonje & Segalla, a new subterranean-stemmed species of Zamia (Zamiaceae) from Mato Grosso and Rondônia, Brazil, is described and illustrated. It is compared to two morphologically similar species with adjacent geographic distributions: Z. boliviana from the Cerrado biome, and the Amazonian species Z. ulei. The new species shares unarmed petioles with Z. boliviana but is readily distinguishable by its much broader leaflets. Z. brasiliensis has leaflets somewhat resembling those of juvenile individuals of Z. ulei, but the latter species is easily differentiated by the presence of prickles on its petiole.

Development of interspecific hybrids between Solanum lycopersicum L. and S. sisymbriifolium Lam. via embryo calli

Solanum sisymbriifolium, a wild relative of the S. lycopersicum species, has been found to be resistant to numerous pathogens which cause severe diseases in Solanaceae crops. It would be highly desirable for species strongly affected by diseases (e.g. tomato) to contain the resistant genes found in their wild relatives. Solanum sisymbriifolium has been considered of potential interest for S. melongena L. breeding, as the former is resistant to several pathogens and resistant interspecific hybrids have been obtained. Additionally, several reports indicate that S. sisymbriifolium is useful for tomato gynogenic haploid production. It is still not quite clear whether S. sisymbriifolium can be crossed with S. lycopersicum and the development of hybrid progeny is possible. In our preliminary in vivo crossing, S. lycopersicum × S. sisymbriifolium diploid embryos were formed inside fruits, but their development was inhibited at the globular stage. To obtain F1 hybrids the embryo-rescue method was implemented. Globular embryos isolated 14–35 dap were cultured on various media showing varied morphogenic potencies. Most of the embryos did not develop on the used media but calli formed from the embryogenic cells in > 17% of the embryos, allowing hybrid plants to be obtained. Ten regenerants, which were adapted in pots containing soil, had morphological traits similar to the S. sisymbriifolium parent, including the plant habit, presence of prickles on shoots or white colour of flowers. The hybrid origin of the regenerants was confirmed by flow cytometry analysis of DNA content and KASP genotyping. The results indicated that S. lycopersicum can be hybridized with S. sisymbriifolium through interspecific hybridization to introduce novel traits for use in tomato-breeding programmes.

Epidermal micromorphology of the genus Festuca L. subgenus Festuca (Poaceae)

Qualitative and some quantitative micromorphological characters of leaf blades, lemmas and paleas were examined using scanning electron microscopy for 29 species of Festuca subgenus Festuca, including the first observations on members of sections Amphigenes, Dimorphae and Cataphyllophorae. The aim of this study was to survey these features in the subgenus Festuca, to assess their taxonomical value. The observed patterns are compared with current taxonomic proposals based on molecular studies. The characters show important taxonomic value, mainly of the abaxial lemma. Characters showing the greatest variation are shape of long cells, shape of the periclinal walls, thickness of anticlinal walls, presence of prickles and abundance of silica bodies. The principal characters of the leaf-blade surfaces include the type and shape of short cells. Two different surface patterns were observed on the lemma, one, long cells rectangular to elongated, with flat to slightly convex periclinal walls and thickened anticlinal walls, for the sections Amphigenes and Dimorphae, and another, long cells rectangular to square, with concave periclinal walls and unthickened anticlinal walls, for the remaining sections. This study confirms the taxonomic value of micromorphological characters in the subgenus Festuca, and that abaxial lemma surface appears to be the most useful.

Phylogenetic Relationships in <I>Solanum</I> Section <I>Androceras</I> (Solanaceae)

Abstract The Leptostemonum clade of Solanum contains approximately 350–450 species, including the cultivated eggplant, S. melongena. This clade is characterized by the presence of prickles and apically attenuate anthers. Solanum section Androceras, the focus of this study, is a group of ca. 12 species belonging to the Leptostemonum clade. This section is unusual in the genus because of its mostly north temperate distribution and distinctive zygomorphic, heterantherous, and enantiostylous flowers. We infer phylogenetic relationships among 43 Solanum taxa, including 11 species and all varieties of sect. Androceras, using DNA sequence data from two nuclear regions (ITS and the granule-bound starch synthase gene [GBSSI or waxy]) and the chloroplast region trnT-F. The combined phylogenetic tree supports sect. Androceras as a monophyletic group sister to Solanum sect. Crinitum. Only one of the three series proposed by previous taxonomists, ser. Pacificum, is supported as monophyletic. Solanum tenuipes from the ...

Scanning electron microscopy of the leaf epidermis of Merostachys Spreng. (Poaceae: Bambusoideae)

This study presents data on leaf micromorphology of 13 species of Merostachys Spreng. (Poaceae: Bambusoideae), a neotropical genus with numerous endemic species. Greatest species richness is found in Central and Southern Brazil, with 41 of the 46 species described. Species were collected in the field at the localities: Itatiaia National Park and Tijuca National Park, Rio de Janeiro State; Fontes do Ipiranga State Park, São Paulo state; Santa Teresa, Espírito Santo State and Rio Doce State Park, Minas Gerais State. Dried plant material came from the herbarium at the São Paulo Botany Institute. The presence of prickles, silica bodies and macro hairs may be especially useful in delimiting species.

Phylogenetic Study of the Genus Piptadenia (Mimosoideae: Leguminosae) using Plastid trnL-F and trnK/matK Sequence Data

We undertook a phylogenetic study of the genus Piptadenia with a sample of 18 of ca. 27 recognized species using DNA sequences from the plastid trnL-F and trnK/matK regions. Parsimony jackknife results support the hypothesis that Piptadenia is polyphyletic and that there are three independent lineages. The largest groups of species form a monophyletic lineage that is sister to Mimosa and corresponds closely to Piptadenia section Piptadenia sensu Barneby. Three species (P. obliqua, P. moniliformis, and P. leucoxylon) of section Pityrocarpa are sister to species of Pseudopiptadenia in a lineage with Parapiptadenia, Microlobius and Stryphnodendron. Piptadenia viridiflora is distantly related to sects. Piptadenia and Pityrocarpa. Section Piptadenia is characterized by the presence of prickles (aculei), a potential synapomorphy linking it to Mimosa, and exserted, racemose or paniculiform inflorescences of aggregated spikes. Piptadenia viridiflora has stipular spines and 1-2 axillary, spicate primary inflorescences. Species of sect. Pityrocarpa are unarmed trees (sometimes with hardened, persistent stipules) whose flowers have recurved petals and an ovary on a long gynophore. We recommend that Piptadenia viridiflora be removed to a new genus, and that Piptadenia be restricted to the other species of sect. Piptadenia. We resurrect the generic name Pityrocarpa to encompass the Pityrocarpa clade and make the following new combinations: Pityrocarpa moniliformis, Pityrocarpa obliqua ssp. brasiliensis, and Pityrocarpa leucoxylon.

AFLP MARKER DEVELOPMENT IN ROSE FOR GENETIC MAPPING: COMPARISON OF THREE RESTRICTION ENZYME PAIRS

AFLP technology was applied to construct genetic linkage maps in rose for use in marker assisted selection. The mapping progeny was created by crossing a black spot resistant amphidiploid (86-7) with a susceptible tetraploid (82-1134). One F 1 hybrid of this cross, 90-69, was open-pollinated to obtain 115 seedlings. AFLP markers were first used to identify and eliminate seedlings produced through cross-fertilization. The remaining progeny set of 52 F 2 plants were used in developing AFLP markers with three combinations of restriction enzymes, EcoRI/MseI, KpnI/MseI. and PstI/MseI. With EcoRI/MseI, primers with three selective bases for each restriction enzyme (+3/+3) yielded an optimum number of bands per gel. However, with KpnI/MseI and PstI/MseI, primers with +2/+3 selective bases produced well-separated bands equivalent in number and dispersion to those produced by +3/+3 selective bases of EcoRI/MseI. One linkage map was constructed for each parent using only single-dose markers. The map of 82-1134 consists of 167 markers assigned to 14 linkage groups and covers more than 682 cM of the genome. The map of 86-7 consists of 171 markers assigned to 15 linkage groups and covers more than 902 cM of its genome. A gene controlling the presence of prickles on the petiole was located at the end of linkage group 7 on the map of 86-7. EcoRI/MseI generated nearly twice as many markers per run than PstI/MseI. Markers developed with three restriction enzyme combinations showed a mixed distribution throughout the maps. Compared to EcoRI/MseI and KpnI/MseI AFLP markers, PstI/MseI markers had a slightly greater distribution in both maps. Overall, PstI/MseI AFLP markers provided the highest percentage of mapped markers.

New Taxa and Combinations in Eleutherococcus (Araliaceae) from Eastern Asia

While preparing a monographic study of Eleutherococcus, we discovered the three new taxa, E. brachypus var. omeiensis, E. huangshanensis, and E. pseudosetulosus, described here. In addition, three new combinations, E. divaricatus var. chiisanensis, E. pilosulus, and E. pubescens, are proposed. Eleutherococcus Maximowicz (1859, emend. C. H. Kim & B.-Y. Sun) is an endemic Asian genus with about 35 species distributed mainly in northeastern Asia including China, Korea, and Japan, with some members also extending to southwestern Asia (Kim, 1997). The genus Acanthopanax (Decaisne & Planchon) Witte was initially recognized as a subgenus of Panax L. by Decaisne and Planchon (1854) and raised to generic rank by Witte (1861). Harms (1894) combined the two genera, and adopted the name Acanthopanax, which has since been widely used by many botanists. However, Acanthopanax does not have priority and is therefore illegitimate under current ICBN nomenclature (Greuter et al., 1994). Some recent authors (e.g., Hu, 1980; Ohashi, 1987; Hsu & Pan, 1993) have therefore transferred taxa from Acanthopanax to Eleutherococcus. Plants of Eleutherococcus are shrubs and are characterized by the presence of prickles, five-merous flowers with two to five carpels, and palmately compound leaves. The genus as a whole is highly variable resulting in much taxonomic confusion (Kim, 1997). For example, E. koreanus Nakai was distinguished from E. senticosus (Ruprecht & Maximowicz) Maximowicz based on its unarmed twigs. However, examination of specimens from various regions has shown this character to be merely included within the limits of natural variation among individuals. While preparing a monographic study of Eleutherococcus, we found three new taxa and describe them here: E. brachypus var. omeiensis, E. huangshanensis, and E. pseudosetulosus; three new combinations are also made: E. divaricatus var. chiisanensis, E. pilosulus, and E. pubescens. Eleutherococcus brachypus (Harms) Nakai var. omeiensis C. H. Kim & B.-Y. Sun, var. nov. TYPE: China. Sichuan: Omei Hsien, Mt. Omei, 10 Oct. 1940, T C. Lee 3794 (holotype, US; isotype, A). Foliola 3, terminalia foliola elliptica, glabra; terminales petioluli ca. 1 cm longi, glabri. Flores cum pedicellis articulatis. A hermaphroditic shrub to 2 m tall; stems erect, glabrous. Leaves 3-foliolate, leaflets elliptic, somewhat chartaceous, glabrous on both surfaces, secondary veins 3 to 5 pairs, the apex obtuse or acuminate, the margin entire, the base cuneate; petiole 0.5 cm long, glabrous; terminal leaflets 2-4 x 11.5 cm, petiolule relatively long, ca. 1 cm; lateral leaflets somewhat smaller than terminal ones, sessile or short-petiolulate. Inflorescence of umbels arranged in a simple cyme at the end of long branches of the current year's growth, rarely at the end of short branches, glabrous; pedicel articulated at uppermost part, 1-1.5 cm long, glabrous. Calyx 5toothed; petals 5; stamens 5; carpels 5, style united into a single column, stigma indistinctly 5-lobed, ca. 1 mm long; ovary 2 mm long. Fruit unknown. This variety is thus far known only from Mt. Omei, Sichuan, China, from which the epithet was derived. The typic variety occurs in Gansu, Shanxi, and Shaanxi in China. Eleutherococcus brachypus var. omeiensis differs from other members of the genus by its articulation in the uppermost part of the pedicel. This variety is also distinguished from the typic variety in having a long (ca. 1 cm) petiolule on the terminal leaflet. Other features are the same and hence we recognize it as a variety of E.

Systematic anatomy of Brachiaria (TRIN.) GRISEB. (Poaceae)

AbstractThe systematic anatomical investigation of 16 West African species of Brachiaria were carried out. The significance of the microscopic observation outlined in the work can be correlated with the taxonomic affinities of the genus and also employed in the identification and classification of sterile materials. The species of the genus are characterized by the embedment of outermost vascular bundles in the outer margin of sclerenchyma, the presence of parenchyma cells in the central ground tissue, the absence of papillae in the long cells of the epidermides, the presence of prickles most especially on the margins on the lamina. The anatomical characters which may help in distinguishing the various species one from another include the shape of subsidiary cells in surface view, dermal appendages, outline of leaf blade in transection and type of Kranz tissue. An artificial key to the 16 species of Brachiaria based on the anatomical features is provided.