Petal Width Research Articles

Quantitative analysis of corolla shapes and petal contours in single-flower cultivars of lisianthus

The shape of the corolla was quantitatively evaluated in 216 cultivars of lisianthus by the use of elliptic Fourier descriptors followed by principal component (PC) analysis. The corolla's shape could be described by using the first and second PC scores, which corresponded to the corolla opening angle and the curvature of the corolla contour, respectively. The scatter plot of these PC scores for all 216 cultivars showed a continuous distribution, rather than any obvious clusters. Using these two parameters, four typical shapes of the corolla could be reconstructed: funnel-shape, bell-shape, shallow-bowl-shape, and cup-shape. Based on this analysis, 8 cultivars representing these four corolla shapes were chosen for the analysis of petal shapes. The petal shapes could be described by using the first and second PC scores representing the petal width and the position of the weighted center, respectively. The first PC was high in funnel- and bell-shaped cultivars, and low in shallow-bowl- and cup-shaped cultivars. The second PC tended to be lower in cup-shaped cultivars than shallow-bowl-shaped cultivars. However, petal shapes could not be discriminated between bell- and funnel-shaped cultivars. The data suggested a close correlation between shapes of individual petals and overall corolla shapes at anthesis, but that some cultivars have the similar petal contours with different three-dimensional curvature.

Swietenia (Meliaceae) flower in Late Oligocene–Early Miocene amber from Simojovel de Allende, Chiapas, Mexico

The amber of Simojovel de Allende, Chiapas, Mexico, of Late Oligocene-Early Miocene age, has yielded a new flower representing the Meliaceae. The flower of Swietenia miocenica Castañeda-Posadas & Cevallos-Ferriz sp. nov. is characterized by small size; free calyx composed of five glabrous lobes, ciliolated along the margin lobes; corolla composed of five free, contortedly inserted petals with ciliolated margins; cylindrical staminal tube ending in 10 acuminate or toothed accessories and 10 sessile anthers; and a discoid stigma divided in five lobular stigmatic glands. The morphology of S. miocenica is well represented among Meliaceae. Although the new species shares many characters with Swietenia microphylla, small differences in the length and width of petals and the length of staminal tube support its recognition as a new species. The presence of this genus demonstrates the establishment of tropical communities in southern Mexico by the early Miocene and highlights the influence of the northern hemisphere flora on the extant neotropical flora of the area.

Characterization of different cytoplasmic male sterility systems in Indian mustard (Brassica juncea L. Czern & Coss)

AbstractSix cytoplasmic male sterility (CMS) systems, viz. moricandia, ogura, oxyrrhina, siifolia, tournefortii and trachystoma of Indian mustard (Brassica juncea L.) were characterized for agronomic and floral characteristics. Introgression of alien cytoplasm caused alterations in different floral traits in ogura, siifolia, tournefortii and trachystoma CMS systems. Varied response to different genetic backgrounds of CMS lines indicated the presence of cytoplasmic–nuclear interaction in alteration of floral traits. On the basis of floral characteristics, CMS systems could be grouped into distinct classes. Siifolia, tournefortii and trachystoma CMS lines had narrow petals, while moricandia, ogura and oxyrrhina had wider petals, which were distinguishable on the basis of visual observations. The ratio between length and width of petals were >2.0 in wide petal group but <2.0 in narrow petal group. Further, the relative position of anther and stigma, which was estimated as the ratio between stamen and style length could differentiate the CMS systems. Stamens were longer than styles in oxyrrhina, equal in moricandia and shorter in ogura, siifolia, tournefortii and trachystoma male sterile lines. Non‐viable pollen grains were present in moricandia and oxyrrhina systems, but absent in other systems. In tournefortii and trachystoma, few flowers showed petaloid corolla. All male sterile lines, except trachystoma, which showed crooked siliqua formation were at par with their respective maintainers for flower initiation, plant height, primary branches, seeds per siliqua, seed yield, harvest index, oil and protein content. In general, flower senescence and maturity occurred earlier in male sterile lines than in their respective maintainer lines.

Phenotypic and Molecular (RAPD) Differentiation of Four Infraspecific Groups of Cultivated Flax (Linum usitatissimum L. subsp. usitatissimum)

Based on agro-botanical characterization data, 3101 accessions of cultivated flax (Linum usitatissimum L. subsp. usitatissimum) from the flax collection held by Plant Gene Resources of Canada (PGRC) were grouped into four infraspecific groups according to the classification proposed by Kulpa and Danert (1962) . The objective of this study was to investigate phenotypic and RAPD variation within and among the four groups to better understand phenotypic and genotypic differentiation within the genepool of cultivated flax. The results of the phenotypic characterization of characters defining the convarieties (capsule dehiscence, plant height, technical stem length and 1000 seed weight) and of other quantitative (petal width, oil content in seeds) and qualitative (RAPD, petal colour, anther colour, petal longitudinal folding and margin folding, ciliation of capsule septa, seed colour) are presented using descriptive statistics. The most frequent convariety in the PGRC genebank was intermediate flax (convar. usitatissimum; 80.7 %), followed by fibre flax (convar. elongatum Vav. et Ell. in Wulff; 13.4%), large-seeded flax (convar. mediterraneum [Vav. ex Ell.] Kulpa et Danert; 5.6%) and dehiscent flax (convar. crepitans [Boenningh.] Kulpa et Danert; 0.3%). Analyses of RAPD data and two qualitative characters (longitudinal and marginal folding of petals) did not show marked differences among the proposed convarieties. However, differences among the convarieties in quantitative traits defining them (plant height, technical stem length and seed size) were considerable. Patterns of variation among the convarieties for other quantitative characters (petal width and seed oil content), as well as the frequencies of character expressions of four qualitative characters (petal colour, anther colour, ciliation of capsule septa and seed colour) were significantly associated with the four proposed convarieties, underlining the phenotypic and genotypic validity of this grouping. The patterns of geographic distribution of the convarieties and important characters showed that certain convarieties dominate in some areas of origin. The infraspecific classification and the presented characterization data increase the transparency of genetic diversity available in cultivated flax and in particular in the PGRC flax collection.

Limitations on reproductive success in endemic Aquilegia viscosa (Ranunculaceae) relative to its widespread congener Aquilegia vulgaris: the interplay of herbivory and pollination

Plant reproduction can be strongly affected by herbivory and different features of pollination ecology, such as pollinator visitation rates and capacity for self-pollination. The purpose of this study is to compare the relative impact of herbivory and pollination on maternal reproductive success in endemic Aquilegia viscosa and its widespread congener Aquilegia vulgaris. We conducted herbivore exclusion experiments in two populations of each species in 2 different years and showed that the maternal fertility of A. viscosa was significantly more limited by floral predation and pre-dispersal seed predation than its widespread congener. In the absence of herbivory, A. viscosa retained significantly lower maternal fertility than A. vulgaris. Experimental pollinations in an insect-free glasshouse showed that the two species have an equal seed/ovule ratio both in the absence of pollinators and in the presence of non-limiting outcross pollination. Pollinator visitation rates were significantly higher in populations of A. vulgaris than in populations of A. viscosa. In addition, path analyses showed that spur length, an important trait for pollinator attraction in Aquilegia, and, indirectly sepal and petal width, contribute positively to the seed/ovule ratio in A. vulgaris, but not in A. viscosa. These results indicate that maternal fertility of endemic A. viscosa is strongly reduced by flower and seed predation despite low rates of pollinator visitation, and that pollen or resource limitation in the wild may further reduce maternal fertility. Finally, floral trait variation appears to be decoupled from fertility variation in endemic A. viscosa, which possibly constrains the evolution of reproductive traits in this species.

Genetic analysis of petal size through genomic manipulation in Brassica

AbstractThe effect of genome composition and cytoplasm on petal size was studied in Brassica. Two accessions of Brassica rapa (2n = 20, AA) were reciprocally crossed with three accessions of Brassica oleracea (2n =18, CC) to produce resynthesized B. napus (2n = 38, AACC or CCAA) and sesquidiploids (2n = 29, AAC or CAA). Petal size was measured and compared among diploids (AA and CC), sesquidiploids (AAC and CAA) and amphidiploids(AACC and CCAA). The results showed that petal size is a genome‐dependent and highly heritable character. The heritability of petal length is as high as 96.3%. The addition of each C‐genome to the AA genomic background increased the petal length by 4‐5 mm. Cytoplasm of B. oleracea showed a positive effect on petal length by about 1.3 mm over that of B. rapa. Petal width was positively correlated with petal length at a highly significant level (r= 0.806, df = 81). Resynthesized B. napus (AACC) showed significantly larger flower petals than natural rapeseed cultivars (AACC).

MORPHOLOGICAL AND CHEMICAL EVALUATION ON HYPERICUM PERFORATUM AND H. MACULATUM IN LITHUANIA

MORPHOLOGICAL AND CHEMICAL EVALUATION ON HYPERICUM PERFORATUM AND H. MACULATUM IN LITHUANIA

Morphological variation in populations of Bletia purpurea (Orchidaceae) and description of the new species B. riparia

Abstract Bletia purpurea is the most widespread species in its genus. Morphological variation has been recognized throughout the range of its distribution. In this paper, the morphological variation from 63 populations (583 individuals) of Bletia purpurea is assessed to determine whether more than one species were present. Forty-four quantitative and qualitative characters were examined by univariate analyses and exploratory multivariate analyses. Univariate analyses indicate that quantitative characters such as lateral sepal width, petal width, lip length, and lip width are significantly different for populations from Acazonica, Mexico. Floral parts in the populations from Acazonica are the smallest among all populations. Qualitative characters such as petals covering the lip midlobe and horizontal lip position are found exclusively in the same populations. We concluded that these populations should be described as a new species, B. riparia. Multivariate analyses indicated that morphological variation am...

Attributes of Individual Flowers of Brassica napus L. are Affected by Defoliation but not by Intraspecific Competition

To investigate the effect of intraspecific competition on flowering in Brassica napus‘Westar’, a series of 30 pots was established that spanned a range of one–96 plants per pot. In each pot, the following attributes of individual flowers were quantified: petal length; petal width; stamen length; pistil length; pollen production; diameter of pollen grains; and nectar production. Certain plants contained a transgenic marker that enabled the vigour of their pollen to be quantified by screening the progeny from post-pollination trials against conventional male competitors. Plant size was strongly affected by plant density; plants in the lowest density pots comprised ten-times more dry biomass than individuals in the highest density pots. However, none of the attributes of individual flowers varied with density. In contrast, the number of flowers per plant declined rapidly with density. In the face of resource scarcity, the plants apparently conserved flower size rather than flower number. There was no difference in the response to density between transgenic and conventional plants, but transgenic plants obtained more fertilizations than expected in post-pollination competition against conventional competitors. A separate experiment demonstrated that B. napus is, nevertheless, capable of plasticity in certain flower attributes (petal size, stamen length) in response to defoliation. Explanations for the stability of flower size relative to flower number are discussed.

Quantitative trait loci for floral morphology in Arabidopsis thaliana.

A central question in biology is how genes control the expression of quantitative variation. We used statistical methods to estimate genetic variation in eight Arabidopsis thaliana floral characters (fresh flower mass, petal length, petal width, sepal length, sepal width, long stamen length, short stamen length, and pistil length) in a cosmopolitan sample of 15 ecotypes. In addition, we used genome-wide quantitative trait locus (QTL) mapping to evaluate the genetic basis of variation in these same traits in the Landsberg erecta x Columbia recombinant inbred line population. There was significant genetic variation for all traits in both the sample of naturally occurring ecotypes and in the Ler x Col recombinant inbred line population. In addition, broad-sense genetic correlations among the traits were positive and high. A composite interval mapping (CIM) analysis detected 18 significant QTL affecting at least one floral character. Eleven QTL were associated with several floral traits, supporting either pleiotropy or tight linkage as major determinants of flower morphological integration. We propose several candidate genes that may underlie these QTL on the basis of positional information and functional arguments. Genome-wide QTL mapping is a promising tool for the discovery of candidate genes controlling morphological development, the detection of novel phenotypic effects for known genes, and in generating a more complete understanding of the genetic basis of floral development.

PC99: a new freeware for manipulating and graphically displaying palaeocurrent data

PC99 is a Windows-based, Visual Basic freeware program that facilitates the graphical presentation and/or comparison of individual or composite palaeocurrent data files. Such data may be displayed using either rose or circular diagrams. Interpretation of palaeocurrent patterns within rose diagrams is aided by a choice of petal width and radial scale. Examples of the program's utility are presented using data derived from well preserved Early Permian point bars, Member C, Weller Coal Measures, Allan Hills, Antarctica.

Differences in the apportionment of molecular and morphological variation in North American strawberry and the consequences for genetic resource management

Variation for 24 morphological traits measured in a greenhouse environment and 36 randomly amplified polymorphic DNA (RAPD) markers was assessed among 318 wild octoploid strawberry (Fragariaspp.) genotypes from diverse habitats across the northern USA. RAPD marker frequencies and certain leaf and flower morphology traits (petiole color, leaf mass/area ratio, leaflet length and width, flower and receptacle diameter, petal width, flowers/inflorescence) were significantly different between the F. chiloensis-platypetala and F. virginiana-glauca species complexes. The proportion of variation accounted for by provenance effects was lower for the RAPD markers than for most morphological traits, especially in the F. virginiana-glauca species complex. Morphological traits of potential adaptive importance group the collection into provenances within each species-complex, and reflect the significant habitat and geographic differences across the region from which the germplasm was collected. Variation among populations within provenances was low for the molecular and most morphological traits, with a much larger amount of variability among plants within populations. Most of the variation for the presumably more selectively-neutral RAPD data was among plants within populations and populations within provenances rather than among the provenances that were recognized based on morphological traits, especially in the F. virginiana-glauca complex. Patterns of diversity for morphological traits must be considered, along with more selectively-neutral molecular characters such as RAPDs, to formulate effective sampling strategies and to properly estimate the quantity and apportionment of diversity within this germplasm.

Platanthera lacera × leucophaea, a new cryptic natural hybrid, and a key to northeastern North American fringed-orchids

To evaluate the putative hybrid origin of fringed-orchids from York County, Ontario, morphological attributes of hybrid flowers were evaluated with respect to both a random sample of herbarium specimens and populations from the hybrid location. The putative hybrids were intermediate in spur length, petal width, and vertical distance across opening to the spur as well as in eight other quantitative characters. The hybrid is named Platanthera ×hollandiae Catling & Brownell (= Platanthera lacera (Michx.) G. Don × Platanthera leucophaea (Nutt.) Lindl.). With pale greenish-white flowers, partly reflexed lateral sepals, and a horizontally linear spur opening, the putative hybrid plants resemble P. lacera but can be readily distinguished by their relatively long spurs, relatively broad lateral petals, and ovoid instead of strap-shaped viscidium. A key including characteristics of the column is included that allows the separation of all northeastern North American fringed-orchids and their known natural hybrids.Key words: orchid, hybrid, Platanthera lacera, Platanthera leucophaea, Canada, Ontario.

Developmental Instability in Fragmented Populations of Prairie Phlox: A Cautionary Tale

Abstract:Considerable attention has recently been focused on using levels of developmental instability among members of a population to detect environmental or genetic stresses on animals or plants. It is not yet clear, however, that high developmental instability in a sample of individuals always indicates environmental stress or poor genetic quality. We studied 13 fragmented populations of prairie phlox ( Phlox pilosaL.) to test the hypothesis that developmental instability should decrease with increasing population size—as expected if small populations suffer genetic problems associated with inbreeding or are exposed to more environmental stress than larger populations. We used two different measures of developmental instability, each calculated for two different traits: radial asymmetry of flowers (for petal width and petal length) and modular fluctuating asymmetry of leaves ( for leaf widths at two points along the leaf ). There were weak but significant correlations among individuals for four of six pairwise combinations of these measures. Surprisingly, three of our four measures of developmental instability showed strong population size effects that were opposite to those expected: developmental instability increased with population size. We conclude that measures of developmental instability cannot be applied uncritically for biomonitoring without considerable knowledge of developmental mechanisms, natural history, and population biology of the species in question.

Use of floral descriptors to study variability in wild cocoa trees (Theobroma cacao L.) in French Guiana

155 clones of wild cocoa trees (Theobroma cacao L.) in French Guiana, belonging to 16 populations identified by surveyors in two different river basins (three sub-basins), along with four international clones used as controls, were characterized with four floral descriptors: petal ligule width, sepal width, gynoecium length and number of ovules per ovary. The data underwent an analysis of variance and a factorial discriminant analysis, and the Mahalanobis distances between the populations were calculated. Significant differences existed between the populations for the four descriptors and the discriminant analysis revealed two main groups among the Guianan cocoa trees. It also isolated them from the controls. The populations in the two basins were not homogeneous, and the sub-basin of origin did not seem to be the main factor structuring the variability of the study populations. There proved to be substantial genotypic variability in the Guianan material for the floral descriptors. Variation within the same family (trees derived from the same pod) was low.

Significance of secondary infections with lily symptomless carlavirus to cut‐flower production of Lilium

Summary.The commercial significance of secondary infections of lily symptomless carlavirus (LSV) to commercial Lilium cut‐flower producers was assessed by comparing growth of plants and quality of blooms produced from bulbs of eight Asiatic and two Oriental hybrid cultivars both infected and free from infection with LSV. In comparison to LSV‐free plants, LSV‐infected plants grown under Tasmanian commercial cut‐flower production conditions had decreased stem length (mean of 8.5% and 10.4% decrease across cultivars in each of two experiments; P= 0.007 and < 0.001) and fresh weight (18.8% and 23.4%; P= 0.008 and 0.004). Bud size was significantly decreased in one experiment (12.3%; P= 0.001), while bud number and vase life were not affected (P= 0.05). LSV‐infected plants grown in a temperature controlled glasshouse had decreased stem length (15.8%; P < 0.001) and petal length (8.7%; P= 0.001) but petal width and bud number were no different to LSV‐free plants (P= 0.05). The characters considered to be of greatest economic importance to cut flower producers (viz the number of inflorescences per stem, flower quality and vase life) were not or were only mildly affected by LSV‐infection in any cultivar and unlikely to be of major commercial concern.

Variation of cultivated flax (Linum usitatissimum L. subsp.usitatissimum) and its wild progenitor pale flax (subsp.angustifolium (Huds.) Thell.)

The domestication of cultivated flax (Linum usitatissimum L. subsp.usitatissimum) is briefly discussed. Using data documented as a matter of routine in genebank work, 63 accessions of cultivated flax from the flax germplasm collection of the Gatersleben Genebank are compared with 73 accessions of its wild progenitor pale flax (subsp.angustifolium (Huds.) Thell.), which have been observed in systematic field trials. Range of variation, genetically based variation, heritability and correlation of several characters are considered, especially with respect to the influence of domestication. Cultivated flax shows higher variation in the characters of generative plant parts, while pale flax varies more in the vegetative parts of the plant. The character correlations are similar in both subspecies. Of the 29 characters studied in pale flax the parameters describing tillering, height of plant, weight of seeds, width of petals and width of leaves are especially suitable for distinguishing between different accessions. In spite of the high heritabilities of most of the characters, the influence of the environment is significant in most cases.

A comparison of quantitative characters of leaf and flower in camellia japonica, C. pitardii, C. reticulata and C. saluenensis.

Camellia japonica (2x) grown naturally in Japan and C. pitardii var. pitardii (2x), C. pitardii var. yulenaleica (6x), C. reticulata (6x) and C, saluenelesis (2x) all grown naturally in Yunnan, the People's Republic of China were computatively compared on the basis of the following slx quantitative characters: (1) petal length; (2) petal width; (3) petal area; (4) Ieaf length; (5) Ieaf width; and (6) Ieaf area. The scatter diagrams of the leaf characters showed character correlation and the main close-relatlonship order of the C. saluenensis-japonica, itardii var. yunnanicaTpitardii var. pitardii-reticulata. The close-relationships proportional to the size of the flowers suggested the successive order of C. salueleensisjapoleica-pitardii var. pitardii-pitardii var. yunnanica-reticulata. Although the size of leaves in C. reticulata from Tengchong, Yunnan, was twice as large as that in C. saluenensls, the ratios of leaf width of both species were quite similar to each other, 2.335 and 2.337, respectrvely Some plants of C. reticulata from Tengchong were morphologlcally quite similar to C. japonica. Camellia pitardii var. yunnanica was consldered conspecific with C. reticulata. Artificial crosses among the four species were readily made. The present biosystematic approach showed the five taxa to be quite closely related to each other and to be isolated only by their geographical distribution.

Correlation and Path Analysis in Jasmine

AbstractCorrelations among 11 morpho‐economic characters and their path analysis were studied using 16 genotype of jasmine. The weight of 100 flowers was significantly associated with the Dower diameter, petal width, petal length, anther length, floral bud length and width, and 100 bud weight in positive direction. Path coefficient analysis revealed 100 flower bud weight and flower diameter to have high direct effect in positive direction. All the other characters affected the yield indirectly through these two characters, indicating that 100 floral bud weight and flower diameter could be taken as selection index.

Comparison of variability in wild Camellia sasanqua Thunberg in connection with possible origin of cultivated variety.

A comparative study of variability in the wild Camellia sasanqua was conducted in 69 study sites covered the majority of the natural populations of the species in Japan. Less-disturbed broad-leaved evergreen forests within the study sites exhibited canopy trees of C.sasanqua up to 1Om in height, up to 46cm in DBH (trunk diameter a.t breast height) and average 125 years in age, while well-disturbed forests of either coppice forests or afforested plantations exhibited mostly sapling trees of C. sasanqua up to 2m in height, up to 2cm in DBH and average 10 years in age, which had large stumps up to 75 cm in diameter. All of the plants from the study sites had the same chromosome number of 2n=90 (hexaploid). The burried seeds of the seed bank have never been long-lived and stored for more than a year. Seed germination, recruitment and plant growth of more open habitats, plentifully supplied with light were expected to allow many more modules to develop. However, the seedlings appeared in low relative light intensity of 12.1% br less suffered a constant probability of death within the frst two years. Signficant correlations were seen between mean leaf length and mean petal length, between mean leaf width and mean petal width, between mean leaf area and mean petal area, between mean leaf length and mean leaf width, and between mean petal length and mean petal width. Nevertheless, those quantitative variations in leaf and flower-petal could not be correlated with differences in habitats. Only four variant forms found were as follows: (1) semi-double flower form of a bud variation in the study site No.6, (2) pinkish-white flower form in the study site No.20, (3) larger petal form in the study site No. 64, and (4) deeply crenate-margin leaf form in the study site No.69. No hybrid was seen in cross-combination between the wild C.sasanqua and its cultivars or other sympatric species which were not seasonally isolated. Since the present wild C.sasanqua was highly adapted to morphological uniformity and quantitative constancy and showed no segregation of morphological and quantitative characteristics, it could involve rarely with cultivar occurrence.