Bract Length Research Articles

Structure of the inflorescences of selected South American species of Abildgaardia Vahl, Bulbostylis Kunth, and Fimbristylis Vahl (Abildgaardieae-Cyperoideae-Cyperaceae)

Abildgaardieae poses several taxonomic challenges, because there is no general agreement on its circumscription and infrageneric divisions. With the objective of providing data with taxonomic and phylogenetic value, the structures of the inflorescences of Abildgaardia, Bulbostylis, and Fimbristylis were analyzed following the methodology and terminology of Troll’s school. The inflorescences studied are polytelic and may comprise only the main florescence or may also show a paracladial zone below it. They are unispiculate, anthela-like, or capitate, and can be terminal, pseudolateral, or in an intermediate position. Normal and prophyllar branching patterns are observed. The acropetal reduction in the order and number of ramifications, and the length of bracts and prophylls were recorded. Foliose structures with an intermediate form between a setaceous bract and a glume are frequently found at the spikelet base. Hypotheses of the homology of these structures, and a list of inflorescence characteristics and character states are presented. The branching pattern of the inflorescence seems to be the main characteristic with potential taxonomic and phylogenetic implications at genus level. The rest of the characteristics could possibly be useful for infrageneric divisions.

Pine Tree Substrate, Nitrogen Rate, Particle Size, and Peat Amendment Affect Poinsettia Growth and Substrate Physical Properties

‘Prestige’ poinsettias (Euphorbia pulcherrima Willd. Ex Klotzsch) were grown at different fertilizer rates in three pine tree substrates (PTS) made from loblolly pine trees (Pinus taeda L.) and a peat-based control. Pine tree substrates were produced from pine trees that were chipped and hammer-milled to a desired particle size. Substrates used in this study included peat-lite (PL), PTS produced with a 2.38-mm screen (PTS1), PTS produced with a 4.76-mm screen (PTS2), and PTS produced with a 4.76-mm screen and amended with 25% peatmoss (v/v) (PTS3). Initial and final substrate physical properties and substrate shrinkage were determined to evaluate changes over the production period. Poinsettias were grown in 1.7-L containers in the fall of 2007 and fertilized at each irrigation with 100, 200, 300, or 400 mg·L−1 nitrogen (N). Shoot dry weight and growth index were higher in PL at 100 mg·L−1 N but similar for all substrates at 300 mg·L−1 N. Bract length was generally the same or longer in all PTS-grown plants compared with plants grown in PL at each fertilizer rate. Postproduction time to wilting was the same for poinsettias grown in PL, PTS1, and PTS3. Initial and final air space was higher in all PTSs compared with PL and container capacity (CC) of PTS1 was equal to PL initially and at the end of the experiment. The initial and final CC of PTS2 was lower than PL. The incorporation of 25% peat (PTS3) increased shoot dry weight and bract length at lower fertilizer rates compared with 4.76 mm PTS alone (PTS2). Substrate shrinkage was not different between PL and PTS1 but greater than shrinkage with the coarser PTS2. This study demonstrates that poinsettia can be successfully grown in a PTS with small particles (2.38-mm screen) or a PTS with large particles (4.76-mm screen) when amended with 25% peatmoss, which results in physical properties (CC and air space) similar to those of PL.

Cypringlea (Cyperaceae) revisited, a new combination and status

Cypringlea (Cyperaceae) es un género segregado de Scirpus, endémico de México, con tres especies.Cypringlea evadens, previamente considerada como variedad de C. analecta o bajo sinonimia de ésta, se reconoce aquí a nivel específico, difiriendo en el grado de división de la inflorescencia, proporción de espigas pedunculadas, número total de espigas, anchura de la hoja y longitud proporcional de las brácteas de la inflorescencia. Se presenta una clave para distinguir las especies, así como descripciones y datos sobre su distribución y hábitat. Cypringlea analecta se cita por primera vez para Nuevo León, Tamaulipas y Querétaro; C. coahuilensis, conocida previamente sólo de la localidad tipo en Coahuila, se da a conocer para Nuevo León; y C. evadens se registra por primera vez para Guerrero y Oaxaca.

Susceptibilidad a Fusarium verticillioides (Sacc.) Nirenberg en la población de maíz MPB-FCA 8561

Susceptibilidad a Fusarium verticillioides (Sacc.) Nirenberg en la población de maíz MPB-FCA 856. Se caracterizó la variabilidad genética de caracteres de la mazorca y susceptibilidad al desarrollo de la podredumbre de la mazorca (Fusarium verticillioides (Sacc.) Nirenberg) en la población de maíz MPB-FCA 856. En Córdoba, Argentina, durante la estación primavera verano 2004/2005, 120 medio hermanos, un híbrido resistente (HR) y otro susceptible (HS), fueron evaluados en un ensayo en bloques completos aleatorizados, con tres repeticiones. Las parcelas fueron dos surcos de 5 m de longitud a 57.000 plantas/ha. En fl oración, los estigmas de cinco plantas elegidas al azar en cada tratamiento, fueron inoculadas en dos oportunidades con el aislamiento P364 en solución conidial (1 x 10^6 ml-1). En madurez fi siológica se midieron seis caracteres de la mazorca. El daño de 96 progenies fue atribuido a F. verticillioides. Se calcularon las varianzas y covarianzas y se estableció la interrelación entre todas las variables. Entre los testigos, HR fue signifi cativamente menos dañado que el 76% de las familias. Los valores de heredabilidad fueron bajos, principalmente para el grado de susceptibilidad (h2=0,0675). Los coefi cientes de variación genética sugieren la selección por resistencia (14,98%) y por la longitud de las brácteas (26,13%). Una mayor longitud de las brácteas y el mayor volumen de los granos, disminuyó signifi cativamente (P < 0,01) el grado de susceptibilidad.

Analysis of Characters and Germplasm of Significance to Improvement of Australian Native Waratahs (Telopea spp., family Proteaceae) for Cut Flower Production

Waratahs (Telopea spp.) are cultivated for their blooms for the international cut flower market. A morphometric study was conducted on a range of cultivated waratah varieties to determine the variability of selected characters of horticultural importance and which parents might be of value in future breeding programs. Univariate analysis of characters of 13 cultivars revealed the greatest range of variation in number of flowers, bract dimensions, flower colour and leaf margin type. Differences were observed between number of flowers per inflorescence in the T. speciosissima (Sm.) R.Br. group of accessions and the other species cultivars; interspecific cultivars with T. mongaensis, Cheel and T. oreades F. Muell. were intermediate, with a similar pattern observed in bract length and width. Multivariate analysis (canonical variate analysis – CVA) discriminated between waratah cultivars on the basis of flower colour (first axis), then flower number, bract length, leaf width and leaf margin type (axis 2). The third axis also separated leaf width, the fourth leaf length and width, and the fifth leaf apex shape, CVA was also used to explore the genetic contribution of three parent T. speciosissima cultivars to hybrid populations. Hybrids with ‘Sunflare’, ‘Sunburst’ or ‘Wirrimbirra White’ as one parent were very dispersed indicating the range of inheritance of the observed phenotypic characters, leading to the possibility of selecting individuals with the required degree of character inheritance. It was demonstrated that the Telopea speciosissima type, which forms the basis of the waratah cut flower industry, may be improved by hybridising with other Telopea species. The application of the results to the development of waratah breeding programs is discussed.

A taxonomic study on genus Rhynchospora Vahl in Korea

Morphological and anatomical characters of selected 3 taxa of Rhynchospora were reexamined. The epidermal patterns of achene and leaf were investigated using a scanning electron microscope (SEM) and a light microscope (LM). Morphological characters such as length and width of bract, spikelet, scale, achene, stem, leaf and leaf sheath, and shape of inflorescence, spikelet, scale, apex of scale, perigynium and achene, and number of stigma and anatomical characters (transectional shape of the stem, and leaf: vascular bundles in stem and leaf epidermal patterns: shape of fundamental epidermal cell and cell wall, type of silica body, subsidiary cell shape, size and frequency of stomatal complex of leaf) were useful for the identification. Keys based on data were presented here.

Morphometry analysis and seed germination of Amaranthus cruentus, A. retroflexus and their hybrid (A. × turicensis)

A morphometric study of Amaranthus cruentus, A. retroflexus and their hybrid, A. × turicensis based on 75 plant samples (750 inflorescences), collected throughout the Olomouc-Holice area (Czech   Republic), is presented. Using multivariete methods (including cluster analysis and canonical discriminant analysis), the existence of three groupings of plants was proven. The hybrid exhibited intermediate values of the width and length of female tepals, length of awl-shaped bracts, and seed size when compared with parental species. A germination experiment showed that dark seeds of A. × turicensis as well as dark seeds of A. retroflexus germinate scarcely and independently on the day length while light seeds of A. cruentus germinate promptly and markedly better under a short day regime. The chromosome analysis showed that A. retroflexus, A. cruentus, and A. × turicensis have the same chromosome number 34.

A taxanomic study on sections Montanae, Limosae, and Paniceae of Carex L. in Korea(Cyperaceae)

Morphological characters of sections Montanae (one taxon), Limosae (one taxon) and Paniceae(seven taxa) of genus Carex (Cyperaceae) were reexamined. The epidermal patterns of perigynium, achene and leaf were investigated using by a scanning microscope (SEM) and a light microscope (LM). Morphological characters such as length and width of stem, leaf, leaf sheath, bract, spike, scale, perigynium and beak of perigynium, length of spike peduncle, size and frequency of stomatal complex of leaf, number of bract, shape of stem transection, scale and spex of scale, beak and base of perigynuim, achene, epidermal cell and cell wall of perigynium, achene, leaf epidermal patterns(fundamental epidermal cell and cell wall, slilica body, subsidiary cell), hair, papillae present/absent of perigynium and leaf were useful for the identification of observed nine taxa. According to the current study, examined nine taxa of sections Montanae, Limosae, and Paniceae were distint from each other regarding length and width stem, leaf, bract, perigynium, perigynium beak, length of spike peduncle, shape of bract, scale and apex of scale, perigynium, perigynium beak, hair present/absent of perigynium and leaf. The key based on data was presented here.

Effects of ultraviolet-B radiation on cotton (Gossypium hirsutum L.) morphology and anatomy.

Cotton (Gossypium hirsutum L.) crop, cultivated between 40 degrees N and 40 degrees S, is currently experiencing 2-11 kJ m-2 d-1 of UV-B radiation. This is predicted to increase in the near future. An experiment was conducted to study the effect of enhanced UV-B radiation on vegetative and reproductive morphology and leaf anatomy of cotton in sunlit, controlled environment chambers. From emergence to harvest, cotton plants were exposed to 0, 8 or 16 kJ m-2 d-1 of UV-B in a square wave approach for 8 h from 0800 to 1600 h. Changes in plant height, internode and branch length, mainstem node number, leaf area, length and area of petals and bracts, and anther number per flower were recorded. Epidermal cell and stomatal density, stomatal index, leaf thickness, and epidermal, palisade and mesophyll tissue thickness were also measured. Initial chlorotic symptoms on leaves turned into necrotic patches on continued exposure to enhanced UV-B. Exposure to high UV-B reduced both vegetative and reproductive parameters and resulted in a smaller canopy indicating sensitivity of cotton to UV-B radiation. Enhanced UV-B radiation increased epicuticular wax content on adaxial leaf surfaces, and stomatal index on both adaxial and abaxial leaf surfaces. Leaf thickness was reduced following exposure to UV-B owing to a decrease in thickness of both the palisade and mesophyll tissue, while the epidermal thickness remained unchanged. The vegetative parameters studied were affected only by high levels of UV-B (16 kJ m-2 d-1), whereas the reproductive parameters were reduced at both ambient (8 kJ m-2 d-1) and high UV-B levels. The study shows that cotton plants are sensitive to UV-B at both the whole plant and anatomical level.

Phylogenetic split of Larix : evidence from paternally inherited cpDNA trn T- trn F region

A molecular phylogeny of Larix comprising 12 species was constructed from the sequence analysis of the paternally inherited cpDNA trnT-trnF region of 46 individuals. The most parsimonious tree split Larix into three sister clades: one clade was composed of two North American species, the other two were short-bracted and long-bracted species of Eurasia respectively except that L. sibirica was clustered in the long-bracted clade. The difference between the present cpDNA phylogeny and previous nrDNA ITS phylogeny in the position of L. sibirica seems to suggest that ancient cytoplasmic gene flow might exist between sections Larix and Multiserialis. The short-bracted L. laricina and long-bracted L. occidentalis have an identical sequence of the trnT-trnF region, which implies that the bract length divergence among North American larches might have occurred recently or chloroplast capture happened during the early differentiation of the two species. The cpDNA results also shed some light on the biogeography of Larix.

A taxonomic study on the Fuirena, Kobresia, and Scleria of Korea(Cyperaceae)

Morphological characters of three taxa belonging to three genera (Fuirena, Kobresia, and Scleria) in Korean Cyperaceae were reexamined. The anatomical patterns of stems and leaves, and epidermal patterns of achenes and leaves were investigated by a scanning electron microscope (SEM) and a light microscope (LM). Based upon the results, the scientific and Korean names, which have not been clearly established, were reviewed. Morphological characters such as length and width of stem, leaf, bract, scale, achene, and shape of achene, spikelet, style base, scale, perianth, and anatomical characters such as shape of stem and leaf, shape of achene epidermal cell and silica body of leaf, size and frequency of stomatal complex, presence of bulliform cell were useful for an identification of the three taxa.

A taxanomic study on sections Foetidae , Arenariae , and Multiflorae of Carex L. in Korea ( Cyperaceae )

Morphological characters of sections Foetidae(one taxon), Arenariae(one taxon) and Multiflorae(six taxa) of genus Carex(Cyperaceae) were reexamined. The epidermal patterns of perigynium, achene and leaf were investigated using by a scanning electron microscope(SEM) and a light microscope(LM). Morphological characters, such as length and width of stem, leaf, leaf sheath, bract, spike, scale, perigynium and beak of perigynium, length of spike peduncle, size and frequency of stomatal complex of leaf, number of bract, shape of stem transection, scale and apex of scale, beak and base of perigynuim, achene, epidermal cell and cell wall of perigynium, achene, leaf epidermal patterns(fundamental epidermal cell and cell wall, silica body, subsidiary cell), hair, papillae present/absent of perigynium, and leaf were useful for the identification of observed eight taxa. According to the current study, examined eight taxa of sections Foetidae, Arenariae and Multiflorae were distinct from each other with respect to length and width of stem, leaf, bract, perigynium, perigynium beak, length of spike peduncle, shape of bract, scale and apex of scale, perigynium, perigynium beak, hair presence/absence of perigynium and leaf. A key based on data was presented here.

A taxonomic study on sect. Rhomboidales Kuk. and sect. Digitatae Fr. of genus Carex L. subgen. Eucarex Cross & Germ. ( Cyperaceae ) in Korea

Morphological characters of sections Rhomboidales (four taxa) and Digitatae (seven taxa) of the subgen. Eucarex (genus Carex, Cyperaceae) were reexamined. The epidermal patterns of perigynium, achene and leaf were investigated by SEM and LM. Morphological characters such as length and width of stem, leaf, bract, spike, scale, perigynium and achene, and shape of cross-sectioned stem, spike, scale, apex of scale, perigynium, beak and base of perigynium, achene, hair present or absent in perigynium, number of involucre and epidermal pattern of perigynium, achene and leaf(shape of fundamental epidermal cell and cell wall, type of silica body, shape of beak epidermal cell and cell wall in perigynium, subsidiary cell shape, size and frequency of stomatal complex of leaf) were useful for the identification of the observed 11 taxa. According to the current study, examined 11 taxa of sections Rhomboidales and Digitatae were distinct from each other regarding by length of leaf, stem, pistillate scale and perigynium, shape and epidermal cell of perigynium beak. C. lanceolata and C. humilis have been confused due to similar morphological characters. C. lanceolata and C. humilis were distinct, however with respect to from length of stem, leaf ligule present or absent, shape of cross-sectioned stem, epidermal patterns of perigynium, achene and leaf. And C. lanceolata could be distinguished from C. pediformis by shape of perigynium and achene, shape of cross-sectioned of stem, epidermal pattern of perigynium, achene and leaf.

A taxanomic study on section Acutae of Carex L. in Korea (Cyperaceae)

Morphological characters of section Atratae of the genus Carex (Cyperaceae) were reexamined. The epidermal patterns of perigynium, achene and leaf were investigated using by a scanning electron microscope (SEM) and a light microscope (LM). Morphological characters such as length and width of stem, leaf, bract, spike, scale, perigynium and achene, and shape of cross-sectioned stem, and leaf, spike, scale, apex of scale, perigynium, beak of perigynium and achene, and epidermal pattern of perigynium, achene and leaf (shape of fundamental epidermal cell and cell wall, type of silica body, shape of beak epidermal cell and cell wall in perigynium, subsidiary cell shape, size and frequency of stomatal complex of leaf) were useful for the identifications of the observed seven taxa. C. gmelinii, C. hancokiana and C. peiktusani have been confused each other due to similar morphological characters. Howerever these taxa were distinct with respect to shape of scale, apex of scale, perigynium, type of silica body, frequence of stomatal complex, subsidal cell shape, and epidermal patterns of achene and leaf.

Aromatherapy: a survey of current practice in the management of rheumatic disease symptoms

In this investigation, morphological, phytochemical and ISSR markers were used to estimate the relationships among and within seven populations of white savory (Satureja mutica), belonging to four provinces in Iran. The individuals were phenotypically diverse, which stamen length, corolla length, corolla diameter, calyx length, bract length, inflorescence length, calyx length and bracteole width were characteristics with the highest variation. Leaf dimensions were in significant correlation with flower and inflorescence characteristics. Chemical compounds of essential oils were found variable in various individuals and all samples were principally composed of phenolic constituents (carvacrol and/or thymol). As a consequence, the plants were classified into two major chemotypes including carvacrol and thymol. A total of 197 band positions were produced by 14 ISSR primers, of which 176 were found polymorphic with 88.91% polymorphism. ISSR genetic similarity values among individuals ranged between 0.45 and 0.94 which was indicative of a high level of genetic variation. Multiple regression analysis (MRA) revealed that phytochemical compositions as dependent variable, showed statistically significant correlation and in association with leaf and flower traits as independent variable, indicating a main role of leaf and flower on production of these compounds. Also, several ISSR fragments were found associated with some morphological traits and phytochemical compositions. The high diversity within and among populations of S. mutica according to different data systems could provide useful information for conservation and selection of cross-parents in breeding programs.

Are ‘Barton’ and ‘Cloud 9’ the Same Cultivar of Cornus florida L.?

Abstract Ten flowering dogwood (Cornus florida) cultivars were evaluated for phenotypic characters including resistance to spot anthracnose and dogwood canker, susceptibility to frost damage, leaf color, bract length and color, bloom number and reproductive phenology. Cultivars differed by at least three phenotypic characters except for ‘Barton’ and ‘Cloud 9’, which when compared with each other, were not significantly different at any characteristic. DNA amplification fingerprinting (DAF) using 17 octamer oligonucleotide primers could not distinguish these cultivars. Furthermore, arbitrary signatures from amplification profiles (ASAP), a technique that produces ‘fingerprints of fingerprints’, which is capable of detecting more differences than DAF, also failed to reveal any polymorphic DNA. Therefore, based on the lack of phenotypic and genetic differences between these two cultivars, we conclude that they are the same genotype.

Comparison of Purple Nutsedge (Cyperus rotundus) from Around the World

Purple nutsedge collections from 13 states within the continental United States and from 21 other locations around the world were studied to compare their reproduction and morphological characteristics. Differences occurred in the number of shoots produced from single tubers, the number of leaves per shoot, and the length and width of leaves. Differences were also found with respect to flowering, length of culms supporting the inflorescences, and number, length, and width of involucral bracts at the apex of the culms. Variations occurred in the flower parts, including the number and length of rachises and the length of rachillae and spikelets. There were differences in the growth patterns of the leaves, with some collections having leaves mostly erect and others having leaves lie more closely to the ground. The color of the leaves varied between light and dark green, and the color of the inflorescence varied between light and dark purplish-brown. Greater variation was found among plants from different locations around the world than from within the continental United States.

Are `Barton' and `Cloud 9' the Same Cultivar of Cornus florida?

Ten cultivars of Cornus florida (Barton, Cherokee Princess, Cloud 9, First Lady, Fragrant Cloud, Plena, Purple Glory, Rubra, Springtime, and Welch's Jr. Miss) were evaluated for horticultural characters of canker incidence, susceptibility to spot anthracnose and freeze damage, bloom number, bract length, and phenology. Of the ten cultivars, only `Barton' and `Cloud 9' were similar for all characteristics studied. DNA amplification fingerprinting (12 standard primers) and Arbitrary Signatures from Amplification Profiles (four minihairpin primers) were used to test our hypothesis that `Barton' and `Cloud 9' were genetically distinct, but phenotypically similar. Polymorphisms were not observed; therefore, we could not reject the null hypothesis that `Barton' and `Cloud 9' are the same genotype.

A numerical taxonomic study of Armeria maritima (Plumbaginaceae) in North America and Greenland

Principal components analysis, discriminant analysis, cluster analysis and two level nested analysis of variance were performed on 961 herbarium specimens of Armeria maritima covering the complete geographic range of the species in North America and Greenland. Among the monomorphic, self-compatible specimens combining coarsely reticulate pollen and papillous stigma, we recognized three subspecies. Along the Pacific coast from California to Vancouver Island, the single taxon ssp. californica is proposed, which includes the formerly described var. purpurea. In arctic and subarctic regions, ssp. sibirica, which includes var. labradorica, and ssp. interior are recognized as distinct entities. The latter has a restricted distribution and can be easily distinguished morphologically owing to its glabrous calyces. The morphological variation between ssp. californica and ssp. sibirica is continuous and some overlap occurs. The best diagnostic characters are two ratios: sheath length to flower head width and outer involucral bract length to flower head width. Geographic trends are obvious: a reduction in plant size with increasing latitude and an increase in frequency from west to east of hairy scapes and holotrichous calyces. The dimorphic and self-incompatible ssp. maritima is maintained because of its distinct breeding system (papillate stigma associated with finely reticulate pollen and smooth stigma associated with coarsely reticulate pollen). Subspecies maritima is only found in south Greenland and some specimens are morphologically similar to eastern monomorphic plants. Key words: Armeria maritima, North America, numerical taxonomy.

Cone and seed morphology of western larch (Larixoccidentalis), alpine larch (Larixlyallii), and their hybrids

Although western larch (Larixoccidentalis Nutt.), alpine larch (Larixlyallii Parl.), and their natural hybrids can be recognized by morphological traits other than those of the reproductive structures, analyses of cone morphology suggest that cone shape and several variables representing bract and scale features, including the ratio of bract length to scale length, also distinguish the taxa. Western larch cones have a smaller length:width ratio than alpine larch. Dry hybrid cones are similar in shape to western larch but when wet they emulate alpine larch. The ratio of bract length to scale length was smallest (1.14) for western larch, intermediate (1.20) for alpine larch, and highest (1.38) for the hybrids. Bract length:width ratio was highest (2.67) for alpine larch, lowest (2.42) for western larch, and intermediate (2.47) for the hybrids. Seeds are less useful in recognizing hybrids, but are distinctive between western and alpine larch. Seeds of alpine larch are much larger than western larch and are triangular in shape; they are easily distinguished from seeds of natural hybrids because hybrid seeds closely resemble western larch seeds.