Search results for "flower"
showing 10 items of 238 documents
An approach to determining anthocyanin synthesis enzyme gene expression in an evolutionary context: an example from Erica plukenetii
2019
Abstract Background and Aims Floral colour in angiosperms can be controlled by variations in the expression of the genes of the anthocyanin pathway. Floral colour shifts influence pollinator specificity. Multiple shifts in floral colour occurred in the diversification of the genus Erica (Ericaceae), from plesiomorphic pink to, for example, red or white flowers. Variation in anthocyanin gene expression and its effects on floral colour in the red-, pink- and white-flowered Erica plukenetii species complex was investigated. Methods Next generation sequencing, reverse transcriptase PCR and real-time reverse transcriptase quantitative PCR were used to quantify anthocyanin gene expression. Key Re…
Differential competitive ability between sexes in the dioecious Antennaria dioica (Asteraceae)
2012
† Background and Aims Differences in competitive ability between the sexes of dioecious plants are expected as a result of allocation trade-offs associated with sex-differential reproductive costs. However, the available data on competitive ability in dioecious plants are scarce and contradictory. In this study sexual competition was eval- uated using the dioecious plant Antennaria dioica in a common garden transplantation experiment. † Methods Male and female plants were grown for 3 years either in isolation, or in competition with a plant of the same sex or the opposite sex. Flowering phenology, sexual and asexual reproduction, plant growth, nutrient content and arbuscular mycorrhizal col…
Variable mycorrhizal benefits on the reproductive output ofGeranium sylvaticum, with special emphasis on the intermediate phenotype
2012
In several gynodioecious species, intermediate sex between female and hermaphrodite has been reported, but few studies have investigated fitness parameters of this intermediate phenotype. Here, we examined the interactions between plant sex and arbuscular mycorrhizal (AM) fungal species affecting the reproductive output of Geranium sylvaticum, a sexually polymorphic plant species with frequent intermediate sexes between females and hermaphrodites, using a common garden experiment. Flowering phenology, AM colonisation levels and several plant vegetative and reproductive parameters, including seed and pollen production, were measured. Differences among sexes were detected in flowering, fruit …
Evolution of gynoecium morphology in Old World Papaveroideae: a combined phylogenetic/ontogenetic approach.
2011
PREMISE OF THE STUDY: The correct assessment of homology is an important prerequisite for reconstructing phylogenetic relationships and character evolution. Old World Papaveroideae (Papaver, Meconopsis, Roemeria, Stylomecon) show substantial diversity in gynoecium and capsule morphology. In particular, capsules can have distinct styles (Meconopsis p.p., Stylomecon) or a sessile stigmatic disc (Papaver). Molecular phylogenetic analyses of Old World Papaveroideae had shown that neither taxa with styles nor those with stigmatic discs represent monophyletic lineages. We here investigate whether either styles or stigmatic discs have arisen repeatedly during the diversification of Old World Papav…
Flowers and inflorescences of the seagrassPosidonia(Posidoniaceae, Alismatales)
2012
Premise of the study: The predominantly aquatic order Alismatales displays a highly variable fl ower groundplan associated with a diverse range of developmental patterns. We present the fi rst detailed description of fl ower anatomy and development in Posidonia , the sole genus of the seagrass family Posidoniaceae. Existing accounts provide confl icting interpretations of fl oral and infl orescence structure, so this investigation is important in clarifying morphological evolution within this early-divergent monocot order. • Methods: We investigated two species of Posidonia using light microscopy and scanning electron microscopy. Our observations are interpreted in the framework of a recent…
Constituents of leaves and flowers essential oils of Helichrysum pallasii (Spreng.) Ledeb. growing wild in Lebanon.
2009
The chemical compositions of the essential oils obtained from leaves and flowers of Helichrysum pallasii were analyzed by gas chromatography and gas chromatography-mass spectrometry. Among the 102 identified constituents, hexadecanoic acid (16.2%), (Z,Z)-9,12-octadecadienoic acid (6.8%), tetradecanoic acid (2.6%), and (Z)-caryophyllene (4.2%) were the main constituent of the oil from leaves, while in the oil from flowers hexadecanoic acid (14.7%), (Z,Z)-9,12-octadecadienoic acid (14.2%), (Z)-caryophyllene (3.6%), and delta-cadinene (3.1%) predominated. The oils were both characterized by sesquiterpenes (33.4% for leaves and 33.7% for flowers, respectively) and fatty acids and esters (30.3% …
Micropropagation ofAgeratum houstonianumby nodal segments
2017
Ageratum houstonianum is a bedding and flowering potted plant originated from Central America which is generally propagate by seed. In this report a preliminary in vitro technique for propagation of A. houstonianum was investigated. In vitro germinated seeds were used to establish aseptic shoot cultures of several clones. Seedling stem segments bearing 3-4 nodes were placed on Murashige and Skoog (MS) basal medium plus 20 g L-1 sucrose, 8.0 g L-1 Agar to induce axillary shoot development. Axillary shoots were subcultured into the same medium and nodal segments were sectioned and subcultured to increase the stock of shoot cultures. Shoot cultures of the selected clone AG14 were used to accom…
Assessing crop coefficients of sunflower and canola using two-source energy balance and thermal radiometry
2014
Abstract A new technique for the local adjustments in crop coefficients is presented. This is an alternative to conventional lysimeter measurements traditionally used for improved irrigation scheduling. The method is based on the combination of a two-source energy balance model and local measurements of radiometric temperatures. Two experimental campaigns were carried out on sunflower and canola in a cropland area located in Barrax, Albacete, in the summer of 2011 and spring of 2012, respectively. Radiometric temperatures of soil and canopy were collected, together with biophysical and meteorological variables. Combining all these data in a two-source energy balance model allowed separation…
Headspace Volatile Composition of the Flowers of Caralluma europaea N.E.Br. (Apocynaceae)
2009
The volatile constituents of the flowers of Caralluma (Apteranthes) europaea (Guss.) N.E. Br. (Apocynaceae - Asclepiadoideae) from Lampedusa Island were analyzed by headspace method. The analyses allowed the identification and quantification of 41 compounds. The main components were, among the monoterpenoids, terpinolene (23.3%), a-terpinene (19.1%) and linalool (18.4%), whereas, among the carbonylic compounds the major constituents were heptanal (2.0%), octanoic acid (2.4%) and hexanoic acid (1.7%). It is worth to mention the presence of a nitrogen containing compound, indole (0.8%) and of a sulphur containing compound, dimethylsulphide (t). The compounds found in the flowers of C. europea…
Space matters: meristem expansion triggers corona formation in Passiflora
2015
Background and aims Flower meristems differ from vegetative meristems in various aspects. One characteristic is the capacity for ongoing meristem expansion providing space for new structures. Here, corona formation in four species of Passiflora is investigated to understand the spatio-temporal conditions of its formation and to clarify homology of the corona elements. Methods One bird-pollinated species with a single-rowed tubular corona (Passiflora tulae) and three insect-pollinated species with three (P. standleyi Killip), four (P. foetida L. ‘Sanctae Martae’) and six (P. foetida L. var. hispida) ray-shaped corona rows are chosen as representative examples for the study. Flower developmen…