Petal Characteristics Research Articles

Genetic analysis and molecular validation of gene conferring petal spot phenotype in interspecific crosses of cotton

Cotton (Gossypium species) has received considerable interest from the geneticists, cytologists and evolutionary biologists since the last more than a century. Here, we explore the genetics of petal spot in the interspecific derivatives involving tetraploid and diploid cottons; and confirm the location of gene governing petal spot phenotype on chromosome A7 by demonstrating co-segregation of SSR marker NAU 2186 with petal spot phenotype. The presence of petal spot was observed to be dominant over its absence. Petal spot inheritance showed significant deviation from the expected Mendelian ratio in all the segregating populations indicating segregation distortion. The distortion was biased towards the hirsutum parent which has important implications from introgression point of view. We also report a strong association between petal spot and petal margin coloration phenotypes. Extant American cotton varieties generally lack petal spot and margin coloration phenotypes. These petal characteristics can serve as morphological markers during germplasm characterization.

Morphology, Taxonomy, Anatomy, and Palynology of the Opium Poppy (Papaver somniferum L.) Cultivation in Northern Thailand.

In this paper, we present the morphology, taxonomy, anatomy, and palynology of Papaver somniferum. A detailed morphological description and illustrations of the species are provided, along with information about the identification, distribution, cultivation areas, habitats, pollinators, specimens examined, growing periods, phenology, etymology, vernacular name, and uses. The species can be characterized as a glabrous and glaucous herb with unlobed or pinnately lobed leaves, and an amplexicaul base; variations in color and morphological characteristics of petals; and white filaments, occasionally purple with a white basal part, broadened at the apical part. Two rings of discontinuous and widely spaced collateral vascular bundles are recognized in the transverse section of the stems. The shape of epidermal cells on the adaxial surface is polygonal, while that on the abaxial surface is polygonal or irregular. The anticlinal cell walls of the epidermal cells on the adaxial surface are straight or slightly curved, while those on the abaxial surface are straight, slightly curved, sinuate, or strongly sinuate. The stomata are anomocytic and are confined to the lower epidermis. The stomatal density is 54-199/mm2 (with a mean of 89.29 ± 24.97). The mesophyll is not distinctly differentiated into palisade and spongy regions. Laticifers are found in the phloem areas of the stems and leaves. The pollen grains can be spheroidal or prolate spheroidal in shape, sometimes oblate spheroidal [polar axis (P) diameter/equatorial axis (E) diameter ratio = 0.99-1.12 (with a mean of 1.03 ± 0.03)]. The pollen aperture is tricolpate and the exine sculpturing is microechinate.

Functional analysis of flower development related gene SvGLOBOSA from Senecio vulgaris.

The unique capitulum of Asteraceae has important ornamental and research value. Few studies have described the complex molecular mechanism of flower development. In this study, SvGLOBOSA(SvGLO), the MADS-box gene of Senecio vulgaris, was identified by screening the transcriptome data, and its function was examined. The gene structure was analyzed and its function was predicted through bioinformatics. The relative expression levels in different tissues of wild-type S. vulgaris were analyzed by qRT-PCR. SvGLO was overexpressed in Solanum nigrum and morphological observations were made. Histological staining was used in analyzing the histological changes in the ovary of transgenic S. nigrum. The results showed that the open reading frame of SvGLO was 591 bp long, encoding 196 amino acids. It has typical MADS-box and K-box domains and contains a PI motif at the C-terminal. SvGLO belongs to the PI/GLO subfamily of class B MADS-box genes. qRT-PCR results showed that SvGLO was highly expressed in inflorescence tissues but not in vegetative organs. In SvGLO-overexpressed S. nigrum, the sepals showed some characteristics of petals, carpels transformed into stamen-like organs, and fruit development was abnormal. Histological staining revealed that the morphology of ovary wall cells of transgenic S. nigrum was similar to that of anther wall cells of the stamen of wild-type S. vulgaris. Therefore, SvGLO may be involved in the regulation of petal and stamen development in S. vulgaris.

Rate/Concentration Kinetic Petals: A Transient Method to Examine the Interplay of Surface Reaction Processes.

Transient pulse response experiments are used to construct rate/concentration kinetic dependencies, RC Petals and provide a new method to distinguish the timing and interplay of adsorption, surface reaction, and product formation on complex (industrial) materials. A petal shape arises as the dynamic "reaction-diffusion" experiment forces the concentration and reaction rate to return to zero. In contrast to the typical steady-state "Langmuir-type" RC dependence, RC petals have two branches, which arise as a result of decoupled gas and surface concentrations in the non-steady-state regime. To demonstrate this approach, the characteristics of petal shapes using ammonia decomposition as a probe reaction are presented. Ammonia, hydrogen, and nitrogen transformation rates are compared on three simple materials: iron, cobalt, and a bimetallic CoFe preparation when ammonia is pulsed at 550 °C in a low-pressure diffusion reactor. All materials demonstrate a two-branch kinetic RC dependence for ammonia adsorption, and rate constants are quantified in the low-coverage regime. We found that H2 and N2 product formation was dependent on the concentration of surface intermediates for all materials with one exception: for cobalt, an additional fast hydrogen generation process was observed; the rate of which coincided with ammonia adsorption. Nitrogen generation was only significant for CoFe and cobalt and on the CoFe catalyst, a self-inhibition property was observed. A method for estimating the number of active sites based on the RC petals is presented and was applied to the iron and CoFe samples. The surface coverage and rate of formation/conversion of surface intermediates are interpreted from the examination of shape characteristics of the RC petals for each material.

Synthesis of low surface-energy polyepichlorohydrin triazoles thin film

In this investigation, a new polymer with low surface energy was synthesized by grafting a triazole group onto polyepichlorohydrin (PECH) rubber that contained no halogens. The chlorine on PECH was first replaced by an azide group, and this attached azide was then converted to a triazole group with alkyl chains using the azide-alkyne Huisgen cycloaddition reaction. Analyses confirmed the structure of final product, PECH-triazole polymer. The grafting reactions increased the surface roughness. The static contact angles of water or CH2I2 droplets on the PECH-azole film were 101.7° and 71.3°, respectively. The advancing and receding contact angles for water on PECH-azide were 119.8° and 13.7°, respectively. The PECH-triazole polymer has omniphobic properties with rose petal characteristics. The PECH-triazole has low dispersive surface energy (21 mN/m) and negligible non-dispersive surface energy, giving a wetting envelope that is similar to the one of PTFE polymer. X-ray photoelectron spectroscopy and transmission infrared spectroscopy suggested that the interactions of the N atoms on the triazole ring and the O atoms on the PECH backbone constrained the orientation of CH2 groups and reduced the surface energy of the thin film.

Vriesea roberto-seidelii (Bromeliaceae): taxonomy, distribution, and conservation based on new records from the Atlantic Forest of Bahia, Espírito Santo, and Rio de Janeiro, Brazil

Vriesea roberto-seidelii is redescribed based on new specimens from Espírito Santo and from Rio de Janeiro states. It is a poorly recorded species, currently represented only by a few incomplete specimens in Brazilian herbaria. Beside the limited taxonomic treatment, we show illustrated photos with additional material supplied to complement the morphology and geographical distribution. Although originally described as related to V. lancifolia, we believe that this taxon is morphologically more closely related to V. longiscapa, from which it can be distinguished by the size of the flowering plant, size of the inflorescence and peduncle, floral bract and petal characteristics. Our data also indicate that its provenance, as mentioned for the type specimen, is incorrect. Rather than occurring in rocky fields from Chapada Diamantina habitats, the species is confined to sandy coastal plain vegetation from southern Bahia, northern Espírito Santo, and Rio de Janeiro. Pictures of live specimens, updated distributional map, and additional specimens are presented.

Petal micromorphology and its relationship to pollination.

The characteristics of petal epidermal conical cells affect the quality of the signals perceived by various pollinators. This study aimed to identify variations in micromorphological characteristics of flower petals and their relationship to melittophily, ornithophily and chiropterophily pollination systems. The petals of 11 species were analysed using scanning electron microscopy and optical microscopy and the micromorphological traits were described, measured and compared using Tukey's test, PCA and cluster analysis. Unlike chiropterophily, all melittophilous and some ornithophilous species possessed adaxial epidermal conical cells. Cluster grouping separated chiropterophilous flowers from melittophilous and ornithophilous. PCA analysis showed that the two morphometric profile of conical cells was the attribute that most strongly influenced the grouping of species. When considering the data set of the three pollination systems, melittophilous and ornithophilous plants were more similar to each other than they were to chriopterophilous species. The distance between conical cell apices is an important parameter in interactions with pollinators. This study facilitated recognition of smoothing pollinator resource access through petal micromorphological characteristics. Further research regarding the biometry of micromorphological traits related to pollination is required.

Development of a Small Sized Cymbidium Variety ‘Snow Bell’ with Light Pink Colored Flower and Frangrance

A Cymbidium variety 'Snow Bell' (C. kanran <TEX>${\times}$</TEX> C. Jack Frost) was developed at the National Institute of Horticultural & Herbal Science, Rural Development Administration in 2011. A cross between C. kanran with small-sized greenish colored flowers and C. Jack Frost with bright pink colored flowers, was conducted in 1999. Based on flower color, leaf shape, flower stalk, and vigor one line was selected. Evaluation and selection trials were conducted from 2006 to 2010. 'Snow Bell' has a light pink sepal (RHS, R56D), red lip (R56A) and a leaf length of 47.5 cm. The average number of flowers on each peduncle is 13.8 and the flower diameter is 6.2 cm. The characteristics of petals and sepals show some incurve and some spreading. 'Snow Bell' has a vigorous growth and a round flower. It has an adequate peduncle height of 50.7 cm compared with leaf length of 47.5 cm, and start blooming in December. In electronic nose analysis, the degree of fragrance between 'Snow Bell' and the C. kanran was similar and both of them showed strong scents, although they had different fragrance patterns.

Molecular basis of floral petaloidy: insights from androecia of Canna indica.

Floral organs that take on the characteristics of petals can occur in all whorls of the monocot order Zingiberales. In Canna indica, the most ornamental or 'petaloid' parts of the flowers are of androecial origin and are considered staminodes. However, the precise nature of these petaloid organs is yet to be determined. In order to gain a better understanding of the genetic basis of androecial identity, a molecular investigation of B- and C-class genes was carried out. Two MADS-box genes GLOBOSA (GLO) and AGAMOUS (AG) were isolated from young inflorescences of C. indica by 3' rapid amplification of cDNA ends polymerase chain reaction (3'-RACE PCR). Sequence characterization and phylogenetic analyses show that CiGLO and CiAG belong to the B- and C-class MADS-box gene family, respectively. CiAG is expressed in petaloid staminodes, the labellum, the fertile stamen and carpels. CiGLO is expressed in petals, petaloid staminodes, the labellum, the fertile stamen and carpels. Expression patterns in mature tissues of CiGLO and CiAG suggest that petaloid staminodes and the labellum are of androecial identity, in agreement with their position within the flower and with described Arabidopsis thaliana expression patterns. Although B- and C-class genes are important components of androecial determination, their expression patterns are not sufficient to explain the distinct morphology observed in staminodes and the fertile stamen in C. indica.

Honey bee handling behaviour on the papilionate flower of Robinia pseudoacacia L.

Papilionate flowers, such as those of Robinia pseudoacacia L., show tripping mechanisms that prevent pollen release: only those bees which apply the right force on petals induce pollen to be deposited on their bodies. Apis mellifera is considered a poor visitor of such flowers, since individuals are usually too weak to trip the mechanism. Despite this, the honey bee pays frequent visits to flowers of R. pseudoacacia and produces a much appreciated unifloral honey. We investigated how bees manipulate R. pseudoacacia flowers, whether they contact the plant’s reproductive core and if there is any appreciable difference related to the manipulation of individual flowers. Honey bees showed two strategies for resource collection, namely legitimate visits and robberies. Legitimate visits were more frequent and about 63 % entailed contact with the flower’s reproductive core. We distinguished two behaviours, one to achieve successful positioning on the flower and the other for nectar intake. These behaviours were clearly perceptible and described by different curves of time frequency distribution. From the beginning to the end of anthesis, flowers were classified into four types on the basis of their morphological and phenological traits. Positioning time differed significantly depending on the flower type, with less time needed for more ageing flowers. Time spent in nectar intake was instead highly variable and independent of flower ageing. Selecting the right flower type would appear to lead to obtaining the R. pseudoacacia reward, overcoming species-specific physical inability. Moreover, the role of honey bees as pollinators of R. pseudoacacia is considered. Finally, the relations between petal characteristics and strength needed to trip the mechanism in papilionate flowers is also discussed in the light of nectar foragers.

Study on Mutant Induction of Gladiolus by in vitro Culture of Petals

Petals of Gladiolus ‘Rose Supreme’ were used to establish regeneration system. Developmental characteristics of petals were observed. A total of 94 plantlets of petal somaclonal line were marked in M 1 generation by ISSR molecular markers and traits were observed in M 3 generation. The results showed that the best medium to induce callus was MS+2, 4-D 4.0 mg • L −1 +6-BA 0.5 mg • L −1 and the best medium to induce somatic embryogenesis was MS+2, 4-D1.0 mg • L −1 +TDZ0.3 mg • L. New petals could be formed from petal callus directly. Pigments of mother plant appeared on plantlets while they were formed from petals. Two mutants were obtained from petal somaclonal line in M 3 generation which demonstrated the correctness of ISSR analysis in M 1 generation.

Evolution of petaloid sepals independent of shifts in B-class MADS box gene expression

Attractive petals are an integral component of animal-pollinated flowers and in many flowering plant species are restricted to the second floral whorl. Interestingly, multiple times during angiosperm evolution, petaloid characteristics have expanded to adjacent floral whorls or to extra-floral organs. Here, we investigate developmental characteristics of petaloid sepals in Rhodochiton atrosanguineum, a close relative of the model species Antirrhinum majus (snapdragon). We undertook this in two ways, first using scanning electron microscopy we investigate the micromorphology of petals and sepals, followed by expression studies of genes usually responsible for the formation of petaloid structures. From our data, we conclude that R. atrosanguineum petaloid sepals lack micromorphological characteristics of petals and that petaloid sepals did not evolve through regulatory evolution of B-class MADS box genes, which have been shown to specify second whorl petal identity in a number of model flowering plant species including snapdragon. These data, in conjunction with other studies, suggests multiple convergent pathways for the evolution of showy sepals.

A NEW SPECIES OF HESPEROLINON (LINACEAE) FROM HUNTING CREEK IN NAPA COUNTY, CALIFORNIA

A new species of Hesperolinon is described that is distinguished by its morphology, particularly its three carpels and styles, dichasial inflorescence, and certain petal characteristics. It is a serpentine endemic and may be related to Hesperolinon bicarpellatum.

Genetic Combining Ability of Petal Shape in Garden Pansy (Viola × wittrockiana Gams) based on Image Analysis

Flower appearance is an important target for improvement in garden pansy (Viola × wittrockiana Gams). Flowers of this species consist of three petal types: inferior, lateral, and superior. By means of principal-components (PC) analysis of elliptic Fourier descriptors (EFDs), we estimated the general and specific combining abilities (GCA and SCA) of the floral characteristics of F1 progeny derived from diallel crosses of four inbred lines. The greatest variation in petal shape was explained by the aspect ratio (the first PC) in each petal type. The second or third PC of each petal type was associated with the curvatures of the various parts of the petal. The highly significant GCA effects indicate the importance of additive genetic variance in the transmission of parental petal characteristics to the progeny. The fact that the SCA mean squares were not significant for aspect ratio and petal area indicates that these characteristics of a single-cross progeny can be sufficiently predicted on the basis of GCA. Significant SCA effects were observed in the curvatures of the distal and proximal parts of lateral and superior petals. Correlation analyses indicated several associations between the shape elements of lateral and superior petals, suggesting that genes for these shape elements may be associated, linked, or pleiotropic in the parents used in this study. We successfully demonstrated the use of EFD–PCA to evaluate the petal shape of garden pansy, and of analyzing combining ability and correlations based on the PC scores of EFDs.

Inducing organ generation in vitro: sepal–petal structures from tobacco flower buds

Tobacco (Nicotiana tabacum L. cv. Wisconsin 38) floral buds with sepal primordia only will continue organ production in a normal manner when excised from the plant and placed on the surface of a simple defined medium lacking growth substances. Such a medium is said to be developmentally inert because it does not induce or direct developmental events in the explant but does permit completion of developmental instructions, if any, carried in the explant. If the medium is supplemented with 10.0 ppm kinetin the bud produces a large but variable number of structures having some characteristics of sepals and some characteristics of petals and then continues with the initiation of fairly normal stamens and then carpels. This paper describes these structures and discusses the effect of kinetin on the regulatory systems controlling floral organ generation.

Morphological and Cytological Studies on Gamma ray Induced Mutants of Perennial Portulaca Grandiflora

Seven mutants of perennial Portulaca gralrdiflora obtained earlier as a result of gamma ray treatment were investigated in more detail. Morphological observations reveal that there is a considerable variation in number, size, shape and distribution of stamens and carpels along with petal characteristics. Meiotic behaviour and pollen fertility of mutants and control were recorded.