ray florets
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2021 ◽  
Vol 46 (4) ◽  
pp. 1095-1106
Author(s):  
María Teresa Becerra ◽  
Jesús Mavárez

Abstract— A new species, Espeletia ocetana (Asteraceae), from about 3500 m a. s. l. in Páramo de Ocetá, Mongua, Boyacá department, Colombia, is described and illustrated. The new species exhibits a caulescent rosette habit (0.7‐1.8 m tall), sessile leaves, elliptic leaf laminae with greyish indumentum, robust bracteate thyrsoid capitulescences spreading laterally from rosette, each holding 16‐37(‐69) capitula, external phyllaries 14.2‐31.1 mm long, and ray florets 13.9‐21.3 mm long arranged in 2.0‐2.9 series. It is markedly different from the majority of other members of the genus, and only slightly similar to E. jaramilloi, from which it can be easily distinguished by its taller stems, wider leaves with a smaller length/width ratio, and longer sheaths. Furthermore, E. ocetana has capitula with ray florets arranged in fewer series, and with longer phyllaries, ray corollas, ray corolla limbs, ray styles, ray style branches, disc florets, and disc styles. In addition, E. ocetana is distributed allopatrically in regard to E. jaramilloi, and differs as well in its ecological preference for humid to very humid shrubby páramos. Espeletia ocetana is rather abundant in its type locality, which is a relatively well-conserved páramo located within the limits of Parque Natural Regional Siscunsí-Ocetá. However, it is absent from road margins, abandoned agriculture fields, and other areas impacted by human activities. Further studies will be necessary to know appropriately the extent of the geographic distribution of E. ocetana, its ecological requirements and its phylogenetic affinities with other species.


2021 ◽  
Vol 106 ◽  
pp. 340-371
Author(s):  
Joel Calvo

The Neotropical genus Pentacalia Cass. (Compositae, Senecioneae) is distributed from southern Mexico to northwestern Argentina, plus two disjunct species that thrive in Brazil. Most species diversity occurs in the montane forests of Colombia, Ecuador, and Peru. It comprises scandent woody plants characterized by displaying alternate leaves (opposite in three species), involucres with supplementary bracts, usually yellow ray florets (when present), sagittate to caudate anther bases, and truncate to obtuse style branches with a crown of sweeping trichomes (sometimes with a tuft of longer trichomes, but not strictly penicillate). The Bolivian species were revised for the first time by Cabrera (1985), who treated the group under Senecio L. sect. Streptothamni Greenm. Because of the subsequent addition of new species and the need of taxonomic arrangements, an updated synopsis of the genus recognizing 18 species is presented. The names P. brittoniana (Hieron.) Cuatrec. and P. miguelii (Cuatrec.) Cuatrec. are synonymized with P. psidiifolia (Rusby) Cuatrec., as well as P. inquisiviensis H. Rob. & Cuatrec. with P. cardenasii (Cuatrec.) Cuatrec. and P. sailapatensis (Cuatrec.) Cuatrec. with P. urubambensis (Cabrera) Cuatrec. Seven names are lectotypified and an epitype is designated for the name P. zongoensis (Cabrera) J. Calvo. The new species P. viburnifolia J. Calvo & A. Fuentes is described. Revised nomenclature, succinct descriptions, taxonomic discussions, lists of specimens examined, and distribution maps are provided for all accepted species, in addition to an identification key. Pictures of living plants are also presented for eight species.


2021 ◽  
Vol 50 (3) ◽  
pp. 541-550
Author(s):  
Rabina Islam ◽  
Nazmul Alam ◽  
Mohammed Kamal Hossain

Ten commercial genotypes of Gerbera jamesonii were evaluated for a number of qualitative and quantitative traits in RCBD at the Botanical Garden of Jahangirnagar University, Savar, Dhaka. Qualitative morphology among 10 genotypes showed significant similarities and dissimilarities. The analysis of variance for all the quantitative traits showed highly significant variations among the genotypes. Genotypes Dutch Diva, Classic Fabio Gold, Candela and Dune proved to be the most suitable and sustainable as they were the best performer for different growth and flower quality parameters. Number of flowers per plant found best in Candela and Dutch Diva (11.33). The phenotypic coefficients of variation (PCV) were found higher than the genotypic coefficients of variation (GCV) for all characters. Maximum GCV and PCV were observed for number of suckers per plant (30.984 and 39.568) followed by number of whorls of ray florets per flower and days to flowering from bud initiation. High heritability values were obtained for all the characters. In high heritability estimate coupled with high genetic advance as percentage of mean was maximum for days to first flowering (32.442), plant height (cm) (17.026) and number of suckers per plant (15.992). Selection would be effective for the character showing high performance in genetic parameter. Path analysis revealed that the diameter of disc florets per flower, stalk girth (cm), number of disc florets per flower, number of ray florets per flower would be selection criteria for improvement in flower number. Based on D2 statistics, 10 genotypes were grouped into 3 clusters, namely cluster I, II and III. Highest number of genotypes was found in cluster I containing 5 genotypes. Scatter diagram represents pattern of genotypic distribution into clustering through principal component scores. Highest inter-cluster distance (22.94) was observed between cluster I and III. The genotypes of cluster II possessed heterogeneous nature and showed highest intra-cluster distance (11.35). Highest cluster mean was observed in cluster II containing four genotypes regarded as the superior than another cluster. Bangladesh J. Bot. 50(3): 541-550, 2021 (September)


Phytotaxa ◽  
2021 ◽  
Vol 514 (3) ◽  
pp. 275-286
Author(s):  
MAYUR D. NANDIKAR ◽  
MILIND M. SARDESAI

Recently described two new species, viz. Pinda shrirangii (Apiaceae) and Vicoa gokhalei (Asteraceae), are reviewed for their taxonomy. An illegitimate Heracleum grandiflorum Dalzell & Gibson (non Steven ex M. Bieb.) is recognised as conspecific with P. shrirangii and proposed as a new synonym of the latter. Vicoa gokhalei is found to be conspecific with V. cernua Dalzell. Consequently, Vicoa cernua sensu Gosavi et al. with inconspicuously ligulate ray florets and more pappose achenes is described here as a new species, viz. Vicoa sahyadrica Nandikar & Sardesai.


2021 ◽  
Vol 46 (2) ◽  
pp. 470-475
Author(s):  
Vinícius Resende Bueno ◽  
Gustavo Heiden

Abstract— A new species of Calea belonging to sect. Meyeria is described and named as an in memoriam tribute to Vicki Ann Funk (1947‐2019), who dedicated her career to plant systematics, specially focusing on the Compositae. Calea funkiana resembles Calea triantha, but is distinguished by the slightly branched habit, apically acute leaves, glabrous ray florets, and, mainly, the villose indumentum of stems, leaves, peduncle, and outer phyllaries. The new species is described and illustrated, its geographic distribution is mapped, and its taxonomic affinities are discussed. Additionally, a key for the species of Calea from Serra do Cipó, Minas Gerais, Southeastern Brazil, is provided.


2021 ◽  
Vol 23 (3) ◽  
pp. 351-355
Author(s):  
M. VIJAYALAXMI ◽  

An experiment was conducted to evaluate ten varieties of gerbera under polyhouse conditions in Hyderabad. Vegetative, flowering and flower characters varied significantly among the cultivars and variations in different growth parameters were prominent. Mean performance of the cultivars revealed that cv. Helix recorded maximum plant height, flower diameter, flower stalk diameter and ray florets. The same cultivar Helix also produced maximum number of suckers per plant, number of flowers per plant, Fresh weight of flower, dry weight of flower and possessed longest field life which was at par with cv. Goliath. The cv. Goliath found superior with respect to maximum chlorophyll content, minimum days required for commence of first-flower and days taken for 50% flowering.Maximum disc diameter and number of leaves were produced by cv. balance. While cv. Savannah had significantly maximum leaf area and length of the flower stalk. However, the cv. ‘Montenegro recorded least mean value in terms of plant height, number of leaves per plant, leaf length, leaf breadth, leaf area, number of suckers, chlorophyll content, flower diameter, flower stalk diameter, ray florets, disc diameter, number of flowers per plant and took maximum days for first flower opening, 50 % flowering and which was late in inducing flowering had lesser duration of flowering. Cultivar Helix exerted best performance on various growth and flower characters along with the cultivars Goliath, Danaellen, Balance and Savannah.


2021 ◽  
Vol 12 ◽  
Author(s):  
Sun-Hyung Lim ◽  
Da-Hye Kim ◽  
Jae-A. Jung ◽  
Jong-Yeol Lee

Chrysanthemum is an important ornamental crop worldwide. Some white-flowered chrysanthemum cultivars produce red ray florets under natural cultivation conditions, but little is known about how this occurs. We compared the expression of anthocyanin biosynthetic and transcription factor genes between white ray florets and those that turned red based on cultivation conditions to comprehend the underlying mechanism. Significant differences in the expression of CmbHLH2 were detected between the florets of different colors. CmbHLH2 generated two alternatively spliced transcripts, designated CmbHLH2Full and CmbHLH2Short. Compared with CmbHLH2Full, CmbHLH2Short encoded a truncated protein with only a partial MYB-interaction region and no other domains normally present in the full-length protein. Unlike the full-length form, the splicing variant protein CmbHLH2Short localized to the cytoplasm and the nucleus and could not interact with CmMYB6. Additionally, CmbHLH2Short failed to activate anthocyanin biosynthetic genes and induce pigment accumulation in transiently transfected tobacco leaves, whereas CmbHLH2Full promoted both processes when simultaneously expressed with CmMYB6. Co-expressing CmbHLH2Full and CmMYB6 also enhanced the promoter activities of CmCHS and CmDFR. Notably, the Arabidopsis tt8-1 mutant, which lacks red pigmentation in the leaves and seeds, could be complemented by the heterologous expression of CmbHLH2Full, which restored red pigmentation and resulted in red pigmentation in high anthocyanin and proanthocyanidin contents in the leaves and seeds, respectively, whereas expression of CmbHLH2Short did not. Together, these results indicate that CmbHLH2 and CmMYB6 interaction plays a key role in the anthocyanin pigmentation changes of ray florets in chrysanthemum. Our findings highlight alternative splicing as a potential approach to modulate anthocyanin biosynthesis in specific tissues.


2021 ◽  
Vol 89-90 ◽  
pp. 83-88
Author(s):  
Olena Andrushchenko ◽  
Volodymyr Levon

Flavonols, anthocyanins, and chalcones were determined during the flowering phase in two genotypes of Cosmos sulphureus (regular species and its cultivar ‘Cosmic Orang’) grown in the М.М. Gryshko National Botanical Garden in Kyiv. Inflorescences, leaves, stems, roots, and separated ray and disc florets were dried and crushed to prepare extracts following three different techniques. In particular, with 80 % (v/v) ethanol following Andreeva & Kalinkina (2000), 3.5 % HCl following Kriventsov (1982), and 0.1 N HCl following Udovenko (1988). The absorbance of flavonoids was measured at 390 nm wavelength for flavonols, 530 nm – for anthocyanins, and 364 nm – for chalcones. The highest content of flavonols was found in inflorescences of both genotypes (87.79 ± 1.64 and 87.99 ± 1.75 mg / 100 g of dry weight (DW), respectively). The content of anthocyanins was found to be ranked by overground organs: inflorescences > leaves > stems. In particular, the content of anthocyanins in the inflorescences of these two genotypes was 188.95 ± 5.20 and 177.14 ± 6.81 mg / 100 g DW, respectively. In the leaves, the content of anthocyanins was 61.32 ± 1.97 and 41.33 ± 2.27 mg / 100 g DW, respectively. In the stems, the content of anthocyanins was 31.63 ± 1.16 and 25.31 ± 0.95 mg / 100 g DW, respectively. In the roots, the anthocyanins were not detected. Among the flavonoids, the highest content, in general, was found for anthocyanins. Similarly, chalcones were also localized in overground organs only and mostly in the inflorescences (39.65 ± 1.25 and 37.93 ± 0.88 mg / 100 g DW, respectively). The content of chalcones in the leaves and stems was much lower than the content of the anthocyanins and flavonols; it significantly varied for two investigated genotypes. During the detailed investigation of the flavonoids content in different parts of the inflorescence, it was found that disc florets in both genotypes had fewer flavonoids than the ray florets.


2021 ◽  
Vol 12 ◽  
Author(s):  
Chenfei Lu ◽  
Yajun Li ◽  
Yumeng Cui ◽  
Jiangshan Ren ◽  
Fangting Qi ◽  
...  

Polyacylated anthocyanins with multiple glycosyl and aromatic acyl groups tend to make flowers display bright and stable blue colours. However, there are few studies on the isolation and functional characterization of genes involved in the polyacylated anthocyanin biosynthesis mechanism, which limits the molecular breeding of truly blue flowers. Senecio cruentus is an important potted ornamental plant, and its blue flowers contain 3′,7-polyacylated delphinidin-type anthocyanins that are not reported in any other plants, suggesting that it harbours abundant gene resources for the molecular breeding of blue flowers. In this study, using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis of blue, carmine and white colours of cineraria cultivars “Venezia” (named VeB, VeC, and VeW, respectively), we found that 3′,7-polyacylated anthocyanin, cinerarin, was the main pigment component that determined the blue colour of ray florets of cineraria. Based on the transcriptome sequencing and differential gene expression (DEG) analysis combined with RT- and qRT-PCR, we found two genes encoding uridine diphosphate glycosyltransferase, named ScUGT1 and ScUGT4; two genes encoding acyl-glucoside-dependent glucosyltransferases which belong to glycoside hydrolase family 1 (GH1), named ScAGGT11 and ScAGGT12; one gene encoding serine carboxypeptidase-like acyltransferase ScSCPL2; and two MYB transcriptional factor genes ScMYB2 and ScMYB4, that were specifically highly expressed in the ray florets of VeB, which indicated that these genes may be involved in cinerarin biosynthesis. The function of ScSCPL2 was analysed by virus-induced gene silencing (VIGS) in cineraria leaves combined with HPLC-MS/MS. ScSCPL2 mainly participated in the 3′ and 7-position acylation of cinerarin. These results will provide new insight into the molecular basis of the polyacylated anthocyanin biosynthesis mechanism in higher plants and are of great significance for blue flower molecular breeding of ornamental plants.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Hua Liu ◽  
Ming Sun ◽  
Huitang Pan ◽  
Tangren Cheng ◽  
Jia Wang ◽  
...  

Abstract Background Chrysanthemum morifolium is one of the most popular ornamental crops. The capitulum, which is the main ornamental part of chrysanthemum plants, consists of ligulate marginal ray florets, an attractive corolla (petals), and radially hermaphroditic disc florets, but no stamens. In Asteraceae species, the zygomorphic ray florets evolved from the actinomorphic disc florets. During this process, the zygomorphic ligulate corolla arose and the stamens were aborted. Although molecular genetic research has clarified ray floret development to some extent, the precise molecular mechanism underlying ray floret development in chrysanthemum remained unclear. Results A CYC2-like gene, Cyc2CL, was cloned from C. morifolium ‘Fenditan’. Subsequent analyses revealed that the alternative splicing of Cyc2CL, which occurred in the flower differentiation stage, resulted in the production of Cyc2CL-1 and Cyc2CL-2 in the apical buds. Prior to this stage, only Cyc2CL-1 was produced in the apical buds. A fluorescence in situ hybridization analysis of labeled Cyc2CL-1 and Cyc2CL-2 RNA indicated that Cyc2CL-2 was first expressed in the involucre tissue during the final involucre differentiation stage, but was subsequently expressed in the receptacle and floret primordia as the floral bud differentiation stage progressed. Moreover, Cyc2CL-2 was highly expressed in the inflorescence tissue during the corolla formation stage, and the expression remained high until the end of the floral bud differentiation stage. Furthermore, the overexpression of Cyc2CL-1 and Cyc2CL-2 in transgenic Arabidopsis inhibited stamen and petal development. Therefore, both Cyc2CL-1 and Cyc2CL-2 encode candidate regulators of petal development and stamen abortion and are important for the ray floret development in chrysanthemum. Conclusion In this study, we characterized the alternatively spliced transcripts of the CYC2-like gene that differ subtly regarding expression and function. The data presented herein will be useful for clarifying the regulatory mechanisms associated with the CYC2-like gene and may also be important for identifying the key genes and molecular mechanisms controlling the development of ray florets in chrysanthemum.


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