Petal Shape Research Articles

過共晶Ａｌ‐Ｓｉ合金の初晶Ｓｉの恒温晶出形態

In hyper-eutectic Al–Si alloys fabricated by 4–N aluminum and 5–N silicon, the morphology of primary silicon crystals at constant temperature of the solid-liquid co-existent temperature region was investigated. Supersaturated, non crystallization of silicon, alloy made by rapid solidification process were re-melted at the solid-liquid co-existent temperature region. The primary silicon was crystallized to the blocky shape. In the case of quenching by the solid-liquid temperature region after the melting, the primary silicon crystals grew to the petal shape. These crystallizations grew with same shape during isothermal holding at the solid-liquid co-existent temperature region. The primary silicon grew that the ration of length/width was reduced slightly, in the case of continuous cooling.

Molecular phylogeny of Coelogyne (Epidendroideae; Orchidaceae) based on plastid RFLPS, matK, and nuclear ribosomal ITS sequences: evidence for polyphyly

To evaluate the monophyly of Coelogyne (Epidendroideae; Orchidaceae) and reveal sectional relationships and relations to allied genera in subtribe Coelogyninae, we collected PCR (polymerase chain reaction) amplified restriction fragment length polymorphisms (RFLPs) from 11 plastid regions for 42 taxa (28 Coelogyne species and 14 representatives of other genera) and three outgroups from Bletiinae and Thuniinae. We also sequenced a large portion of the plastid trnK intron (mostly matK) and the nuclear ribosomal DNA internal transcribed spacers ITS1 and ITS2 (including the 5.8S gene). Separate phylogenetic analyses on each data set using maximum parsimony produced mainly congruent (except for the position of Panisea) but weakly supported clades. Parsimony analysis of the combined data clearly identified three main clades in Coelogyninae. Whereas Coelogyninae are monophyletic, Coelogyne is polyphyletic, with species falling into at least two well-supported clades. The utility of morphological characters used in previous classifications was explored by reconstructing character state evolution on one of the four molecular trees. Lip base and petal shape were homoplasious, whereas ovary indumentum and flower number were congruent with well-supported groups. The implications of our results for the classification of Coelogyne are discussed, and a reorganization of the genus by including Neogyna and Pholidota and removing several species is proposed.

Induction of Morphologically Changed Petals from Mutagen-treated Apical Buds of Rose and Plant Regeneration from Varied Petal-derived Calli.

The apical buds of lateral branches asexually multiplied by cutting were treated with some chemical mutagens, and the growth and differentiation or morphological changes of the mutagen-treated buds were traced in developed flowers. As a result, the variations in size, shape, color and number of petals were detected most frequently in the flowers that were developed from apical buds treated with N-methyl-N'-nitro-N-nitrosoguanidine at 100μg ml-1. The variant petals were cultured on MS medium supplemented with NAA and BAP for in vitro isolation and multiplication of morphologically altered rose plants. Embryogenic calli were obtained via adventitious roots induced from the petals and successfully differentiated to intact plants. Consequently, the regenerated plants produced the varied flower different from that originally used for tissue culture. Thus, the present study suggested that our approach would provide an effective method for easily and rapidly inducing variations in flowers of rose and for in vitro multiplication of their regenerants.

Floral ontogeny and morphology of Cevallia, Fuertesia, and Gronovia (Loasaceae Subfamily Gronovioideae)

Members of Loasaceae subfamily Gronovioideae have distinctive flowers compared to those of other members of the family. In contrast to all other Loasaceae, they have haplostemonous androecia and uniovulate gynoecia. The haplostemonous androecia are paedomorphic. The two major clades of gronovioids—(1) Petalonyx and (2) Cevallia, Fuertesia, and Gronovia—differ in their avenues of diversification. The clade consisting of Cevallia, Fuertesia, and Gronovia has floral variation that is manifested most prominently in stamen, stigma, and nectary forms, although petal shapes and the positions of anthers relative to petals and stigmas also vary. The Petalonyx clade exhibits variation that is manifested in morphological differentiation among stamens (Petalonyx crenatus has staminodes) and in postgenital fusion in the corolla (lacking only in Petalonyx linearis and P. crenatus). Developmental studies have also shown that Gronovioideae share with their sister group Mentzelia the loss of a petal‐stamen synorganization that is present in other investigated members of Loasaceae.

ADVENTITIOUS REGENERATION IN ROOT CULTURE OF A SELECTION OF PELARGONIUM X HORTORUM CULTIVARS: AN ASSESSMENT OF CAULOGENIC POTENTIAL AND GENETIC STABILITY

Root explants from twenty two Pelargonium x hortorum FI hybrids were assessed for their caulogenic potential in vitro in response to media containing 4.4 g 1 -1 Murashige and Skoog (1962) basal medium containing 30 g 1 -1 sucrose. 8 g 1 -1 agar and varying concentrations of the growth regulators tri-iodobenzoic acid (TIBA) and thidiazuron (TDZ) at pH 5.8. Caulogenic potential varied from zero to five shoots per explant. Twenty of the FI hybrids produced shoots. At least 50 rooted shoots from the control and root derived population for twenty genotypes were established in vivo and assessed visually for morphological uniformity up to flowering. Visual examination showed no signs of morphological variation with respect to leaf shape, petal shape, flower colour and plant habit except for cvs. Pink Elite and Red Elite. Progeny derived from the latter had 5.5 % and 10 % plants, with variable leaf shape, respectively.

The role of genes influencing the corolla in pollination of Antirrhinum majus

ABSTRACTStudies of pollination ecology have been hindered by an absence of biochemical information about the basis of polymorphism. Using model plants and mutant lines described by molecular genetics may circumvent this difficulty. Mutation of genes controlling petal colour and petal epidermal cell shape in Antirrhinum majus was previously shown to influence fruit set. White flowers set less fruit than magenta flowers and mutants with flat petal epidermal cells set less fruit than flowers with conical cells. Here we analyse the causal pathway underlying this phenomenon through a study of floral characteristics and bee behaviour. Results indicate that bees recognized plants with magenta conical‐celled flowers at a distance and did not approach white flowers or magenta flat‐celled flowers so frequently. Petal cell shape interacted with colour in determining whether an approaching bee landed on a flower within a plot and whether a bee landing on a flower would probe it. The intrafloral temperature of flowers with conical petal cells was shown to increase with solar irradiance, unlike the intrafloral temperature of flowers with flat petal cells. The difference in fruit set may reflect pollinator discrimination between genotypes as a consequence of the effect of intrafloral temperature on nectar quality and quantity.

Control of Organ Asymmetry in Flowers of Antirrhinum

Organ asymmetry is thought to have evolved many times independently in plants. In Antirrhinum, asymmetry of the flower and its component organs requires cyc and dich gene activity. We show that, like cyc, the dich gene encodes a product belonging to the TCP family of DNA-binding proteins that is first expressed in the dorsal domain of early floral meristems. However, whereas cyc continues to be expressed throughout dorsal regions, expression of dich eventually becomes restricted to the most dorsal half of each dorsal petal. This correlates with the effects of dich mutations and ectopic cyc expression on petal shape, providing an indication that plant organ asymmetry can reflect subdomains of gene activity. Taken together, the results indicate that plant organ asymmetry can arise through a series of steps during which early asymmetry in the developing meristem is progressively built upon.

Floral Development and Anatomy ofMoringa oleifera(Moringaceae): What is the Evidence for a Capparalean or Sapindalean Affinity?

Abstract Floral development and anatomy of Moringa have been investigated in the context of the disputed view of a capparalean affinity. Flowers arise in terminal or axillary panicles. Sepals arise sequentially and petals simultaneously. Antepetalous stamens arise simultaneously and precede the antesepalous staminodes, which emerge sequentially. Within their respective whorls, the petals and stamens become twisted along different orientations. The gynoecium develops as a ring primordium on which three carpellary lobes become demarcated simultaneously. A saccate ovary bears numerous ovules on a parietal placentation and is topped by a hollow style. The interpretation of laminal placentation is denied. Monothecal anthers are formed by the failure of one half to initiate. The flowers present a peculiar form of zygomorphy running transversally from the petal between sepals 3 and 5 to sepal 4. The shape and position of petals and stamens is related to a pollen presentation mechanism with bowl-shaped anthers on different levels. The floral anatomy also reflects the zygomorphy of the flower. Although Moringa shares important morphological features with certain members of the Sapindales and Capparales, differences in ontogeny make a close relationship with either Capparales or certain Sapindales appear uncertain.

The role of petal cell shape and pigmentation in pollination success in Antirrhinum majus

The role of petal cell shape and pigmentation in pollination success in Antirrhinum majus

The role of petal cell shape and pigmentation in pollination success in Antirrhinum majus

The nature of the selective pressures which have resulted in the conical-papillate shape of the cells of the adaxial epidermis of many petals has been a matter for considerable speculation. One suggestion is that this shape focuses light within epidermal cells resulting in an increase in the amount of light absorbed by the floral pigments, intensifying the colour of the petals and possibly enhancing their attractiveness to potential pollinators; another is that conical cells aid pollinator orientation on the flower, either visually or when touched. The recent identification of a mutation at the MIXTA locus of Antirrhinum majus (which blocks the formation of conical petal cells) has allowed us to test this hypothesis. We report the results of field experiments indicating that, where pollinator number limits seed-set, flowers with conical epidermal cells receive more pollinator attention than do those with flat cells. Through the use of double mutants we have examined whether preferences for flowers with conical cells operate through the perception of flavonoid pigments. We have also examined the appearance of flowers with and without conical cells under ultraviolet light to determine whether differences in absorption or reflectance of light at these wavelengths may influence pollinator preference.

A reappraisal of the generic status of Liparia and Priestleya (Fabaceae)

SummarySchutte, A. L. & Van Wyk, B‐E.: A reappraisal of the generic status of Liparia and Priestleya (Fabaceae). – Taxon 43: 573‐582. 1994. – ISSN 0040‐0262.The generic delimitation of Liparia L. and Priestleya DC. (Fabaceae, tribe Liparieae) is reevaluated. Traditionally the shape and size of the carinal lobe of the calyx, the shape of the keel petals and the number of flowers per inflorescence were used as diagnostic characters. A study of morphological and alkaloid variation indicates that the two genera run much into one another. Differences in inflorescence and floral structure can be attributed to adaptations to different pollination strategies. The unique combination of major alkaloids occurring in both genera also suggests that they are congeneric. Priestleya is therefore placed into synonymy under Liparia. The nomenclature, synonymy and typification of the genus and the 14 species recognized are presented, and some necessary new combinations are made.

Variation in leaves and petals of Ranunculus subgenus Batrachium on the Aegean Islands, analysed by multivariate analysis

Abstract Variation in leaves and petals was studied using canonical variate and cluster analyses. In total of 33 populations from eight islands leaf variation in laminar, floating leaves was studied in Ranunculus peltatus subsp. peltatus , subsp. baudotii and subsp. saniculifolius , and in R. tripartitus , all of which are heterophyllous in the Aegean area. The petal data set also included the homophyllous R. trichophyllus . The results of the analyses show that the populations are morphologically well differentiated and that petal shape has a tendency to discriminate between the populations somewhat better than leaf shape does. There was no basis for subdividing the populations into taxa on these characters. Analyses showed that up to 70% of the variation was distributed between populations, the remainder (5-18%) being within populations.

Variation in leaves and petals of Ranunculus subgenus Batrachium on the Aegean Islands, analysed by multivariate analysis

Variation in leaves and petals was studied using canonical variate and cluster analyses. In total of 33 populations from eight islands leaf variation in laminar, floating leaves was studied in Ranunculus peltatus subsp. peltatus , subsp. baudotii and subsp. saniculifolius, and in R. tripartitus, all of which are heterophyllous in the Aegean area. The petal data set also included the homophyllous R. trichophyllus. The results of the analyses show that the populations are morphologically well differentiated and that petal shape has a tendency to discriminate between the populations somewhat better than leaf shape does. There was no basis for subdividing the populations into taxa on these characters. Analyses showed that up to 70% of the variation was distributed between populations, the remainder (5-18%) being within populations.

Breeding of alstroemeria (Alstroemeria spp. L.)

Alstroemeria, as a cut flower is a very new plant. The first cultivar Walter Fleming (synonym ‘Orchid’) was bred in 1948. Today, alstroemeria is one of the most important cut flowers in Europe. The number of cultivars grows very fast now exceeds 200. They have been developed by conventional and mutational breeding. The main centers of breeding new cultivars are Holland and Poland. For the induction of mutations, X and gamma rays as well as fast neutrons are used. Mutations of flower colour, petal design, petal shape, change of flower size, plant vigour, productivity and season of bloom were recorded. The range of optimal does of gamma rays for induction of useful mutations was 3-7 Gy. In the case of triploid cvs. 50 Gy of gamma rays was a lethal dose. As the result of mutation breeding 7 new Polish cvs were registered to the end of 1993 and 4 from crossbreeding 3 of Butterfly type and one with yellow flowers with vanilla fragrance, blooming all the year round.

Damage of Plain Woven Carbon/Epoxy Composite Laminates Subjected to Falling Weight Impact.

The progress of damage in perforation impact of plain woven carbon/epoxy laminates was studied using an instrumented falling weight impact testing machine. The thermal deply technique was applied to investigate the three-dimensional distribution of damage such as fiber breakage and delamination at various impact energy levels. The damage process was divided into three different stages according to the growth of main cracks with fiber breakage. In the first stage, surface cracks grew. The second stage was characterized by the propagation of through-thickness cracks. In the last stage, bending fractures of petal shape occurred. In the first and second stages, the absorbed impact energy was found to be a linear function of both the main crack area and the total delamination area. Thus, the contribution of fiber breakage and delamination was determined. The contribution of delamination was unexpectedly large.

Vegetative and floral characteristics of interspecific Brassica chimeras produced by in vitro grafting

Interspecific Brassica chimeras (Brassica campestris+B. oleracea) were synthesized according to an in vitro graftculture method, and propagated by tissue culture of axillary buds or chimeric explants. A total of 127 regenerants obtained were investigated. The mericlinal chimera type was more easily produced than the other periclinal and revertant types. No sectorial chimera was produced. The flowering habit and inflorescence type of the chimeras were found to be controlled by the constitution of three tissue layers, but the petal shape and color were controlled only by the two outer tissue layers. Pollen viability of the chimeras were generally lower and more variable in parts than those of the parental types.

TRANSMISSION PATTERNS OF SELECTED MORPHOLOGICAL TRAITS IN INTERSPECIFIC EXACUM HYBRIDS

The morphology of interspecific Exacum hybrids was investigated in order to determine transmission patterns of several horticultural traits and to confirm interspecific hybrid status of plants. The evaluations utilized 557 accessions from interspecific hybridization of the following species: Exacum. macranthum, E. pallidum, E. pedunculatum, E. trinervium ssp. ritigalensis, and E. trinervium ssp. trinervium. Transmission patterns are proposed for stem shape (three phenotypes- clylindrical, winged-cylindrical and qudrangular; no dominance), petal shape (two phenotypes-rounded and acuminate; rounded dominant to acuminate) and flower form (two phenotypes- imbricate and separate; imbricate dominant to separate) Examination of the progenies confirm interspecific hybridization by the appearance of combinations of traits from the parental species and/or the observation of unique forms not previously observed.

Miniature Gladiolus Cultivars Bred for Winter Flowering

Most of the commercial gladioli in the world have been bred to provide cut flowers in the summer. Growing these cultivars in subtropical and Mediterranean climates during the winter months frequently results in low-quality flowers (Halevy, 1985; Magic and Cowperthwaite, 1954; McKay et al., 1981; Shillo and Halevy, 1976a). The failure to grow high-quality gladiolus flowers during the winter months has been attributed to the sensitivity of these summer cultivars to low light intensities (Shillo and Halevy, 1975, 1976b), short photoperiods (Shillo and Halevy, 1976c, 1981), and the combined effect of low irradiance with low night temperatures (Halevy, 1985; Shillo and Halevy, 1963) during flower development. The European restriction on the importation of cut flowers to the winter months generated the need to develop gladiolus cultivars selected to produce high-quality flowers under winter conditions. [In December, the average daylength in Tel-Aviv, Israel, is 10 h and 5 rein, with an average irradiance of 850 to 1000 μmol·s ·2 (400-700 nm).] In addition, the flower industry required a smaller, lightweight flower able to respond favorably to higher density planting, produce higher yields, and reduce shipping costs. In response to the demands of the cut flower industry and the renewed interest in smaller cultivars (Barnard, 1972; Halevy et al., 1984), a new group of miniature gladiolus was developed for the cut flower market. Their main properties are: winter flowering, light weight, and attractive variety of colors. The group was nicknamed ‘Orchidiola’ (orchid glads) by the Israeli flower industry. The name was inspired by the petal shape and the variation

Uma nova espécie do gênero Cynometra L. (Caesalpiniaceae) para o Estado do Pará, Brasil

Cynometra marleneae is new a taxon discovered after a detailed analysis of the species in the genus. This species differs considerably from the others studied in the shape and thichness of leaflets, shape of petals and number of racemes per axil, among other characters. It is known only from the Trombetas river and tributaries, Pará state.

Outcrossing in Peach

Abstract Malate dehydrogenase (MDH) isozyme variability in peach [Prunus persica (L.) Batsch.] cultivars allowed estimation of outcrossing. After correction for undetectable pollen (of the same genotype as the homozygous Mdh-aa female parents), mean rates of outcrossing of 33% in 1984 and 15% in 1985 were observed. Although no significant cultivar or season effects were observed, a large amount of random variation was present, probably due to uncontrolled variables, such as pollinator behavior and weather conditions. Differences in floral morphology (showy vs. nonshowy flowers, flower color, and petal shape) did not influence rates of outcrossing. Chemical name used: L-Malate:NAD+ oxidoreductase (EC 1.1.1.37, malate dehydrogenase).