Floral biology of Hemigenia and Microcorys (Lamiaceae)

2005 ◽  
Vol 53 (2) ◽  
pp. 147 ◽  
Author(s):  
Greg Guerin
Keyword(s):  
Connective Tissue ◽  
Reproductive Isolation ◽  
Floral Morphology ◽  
Corolla Tube ◽  
Floral Biology ◽  
Pollen Deposition ◽  
Field Observations ◽  
Bird Pollination ◽  
Insect Pollinators

The floral morphology and pollination of Hemigenia R.Br. and Microcorys R.Br. (Lamiaceae) were examined in the field and laboratory. The protandrous flowers have tubular, two-lipped corollas. Nine floral morphotypes are described. The stamens may be completely sterile (staminodal) or have one theca reduced or absent. The anthers typically have elongated connective tissue and are mobile on the filament. When the lower end of the anther is pushed, the upper end is levered towards the mouth of the corolla tube, hence dusting the pollinator precisely where receptive stigmas will later touch. Bearding on the anthers of the adaxial stamens catches adjacent anthers so that they lever in unison. Staminodes guide insect pollinators into the throat to allow precise pollen dusting. Detailed field observations show that bees and flies are the principle pollinators of most species. Floral morphologies are related to pollinator castes, and reproductive isolation and efficiency is enhanced by precise pollen deposition. Bird pollination is likely to have arisen independently in several taxa. The floral arrangement of these taxa is superficially similar but the syndrome is achieved through different anatomy.

scholarly journals Pollination of Pagamea duckei Standl. (Rubiaceae): a functionally dioecious species

2012 ◽  
Vol 12 (4) ◽  
pp. 98-104 ◽  
Author(s):  
Mário Henrique Terra-Araujo ◽  
Antonio Carlos Webber ◽  
Alberto Vicentini
Keyword(s):  
Breeding System ◽  
Floral Morphology ◽  
Corolla Tube ◽  
Floral Biology ◽  
Flower Morphology ◽  
Crossing Experiments ◽  
Dioecious Species ◽  
Pollen Vectors

The floral biology, pollination and breeding system of Pagamea duckei Standl. (Rubiaceae) were studied at the Reserva Biológica da Campina, Manaus, Amazonas, Brazil. Floral morphology suggested that P. duckei is a distylous species. However, crossing experiments revealed that it is functionally dioecious. The flowers are actinomorphic, yellowish, produce nectar and a sweet odor, which is more intense in the morning. Anthesis started in the morning between 5.00 and 6.00 AM and extended until dusk, when the corolla tube abscissed. The flowers were visited mostly by bees of the genus Melipona. Pagamea duckei is not agamospermic and thus needs pollen vectors for effective pollination. The results of this study strengthen the idea that, in Pagamea, species with distylous flower morphology are actually functionally dioecious.

Quantitative Trait Loci Affecting Differences in Floral Morphology Between Two Species of Monkeyflower (Mimulus)

Genetics ◽  
1998 ◽  
Vol 149 (1) ◽  
pp. 367-382 ◽  
Author(s):  
H D Bradshaw ◽  
Kevin G Otto ◽  
Barbara E Frewen ◽  
John K McKay ◽  
Douglas W Schemske
Keyword(s):  
Quantitative Trait Loci ◽  
Reproductive Isolation ◽  
Quantitative Trait ◽  
Floral Morphology ◽  
Cumulative Effect ◽  
Sympatric Species ◽  
Accurate Estimate ◽  
Phenotypic Variance ◽  
Trait Loci ◽  
Morphological Differences

Abstract Conspicuous differences in floral morphology are partly responsible for reproductive isolation between two sympatric species of monkeyflower because of their effect on visitation of the flowers by different pollinators. Mimulus lewisii flowers are visited primarily by bumblebees, whereas M. cardinalis flowers are visited mostly by hummingbirds. The genetic control of 12 morphological differences between the flowers of M. lewisii and M. cardinalis was explored in a large linkage mapping population of F2 plants (n = 465) to provide an accurate estimate of the number and magnitude of effect of quantitative trait loci (QTLs) governing each character. Between one and six QTLs were identified for each trait. Most (9/12) traits appear to be controlled in part by at least one major QTL explaining ≥25% of the total phenotypic variance. This implies that either single genes of individually large effect or linked clusters of genes with a large cumulative effect can play a role in the evolution of reproductive isolation and speciation.

scholarly journals Floral biology of Jatropha curcas L.

2010 ◽  
pp. 31-54
Author(s):  
Angelo Jay Noriel ◽  
Othello Capuno
Keyword(s):  
Jatropha Curcas ◽  
Floral Morphology ◽  
Sunshine Duration ◽  
Pollen Viability ◽  
Floral Biology ◽  
State University ◽  
Anther Dehiscence ◽  
Full Bloom ◽  
Flower Opening ◽  
Male Flowers

This study was conducted at the existing plantation of Jatropha curcas within the campus of Visayas State University, Visca, Baybay, Leyte from April 2006 to June 2006 with the following objectives: 1) to study the floral morphology and flowering behavior of J. curcas; 2) to determine the time and duration of flower opening, anther dehiscence, and stigmatic receptivity of J. curcas; and 3) to test for pollen viability. Male and female flowers of J. curcas were borne on the same plant with an average numbers per inflorescence of 55.03 and 1.926, respectively. Male flowers were more numerous than the females without definite relationship on number per inflorescence. It took an average of 9.56 days for all florets to full bloom. Anther dehiscence was observed to start at the time of opening of male flowers at around 0500 to 0600 hours and remained so for 24 to 72 hours. Stigmatic receptivity started about 12 hours after full bloom and lasted for about 24 hours. Based on observations, opening of floret buds, anther dehiscence, and stigmatic receptivity were all greatly influenced by the environment. Early sunrise, longer sunshine duration, and less amount of rainfall enhanced flowering of J. curcas. Pollen viability was relatively high, ranging from 88.12% to 98.55%.

Floral Biology and Inefficient Pollen Removal in Banksia spinulosa var neoanglica (Proteaceae)

1991 ◽  
Vol 39 (2) ◽  
pp. 167 ◽  
Author(s):  
G Vaughton ◽  
M Ramsey
Keyword(s):  
Fruit Set ◽  
Floral Biology ◽  
Fruit Production ◽  
Pollen Deposition ◽  
Stigma Receptivity ◽  
Flower Opening ◽  
Pollen Removal ◽  
Pollen Longevity ◽  
Floral Visitors

Stigma receptivity, pollen longevity and rates of flower opening were examined in Banksia spinulosa var. neoanglica. The interaction between these aspects of floral biology and removal of self pollen by floral visitors, autogamous pollen deposition and autogamous fruit set was determined. Flowers were strongly protandrous; most stigmatic grooves opened and maximum stigma receptivity occurred 3-4 days after the flowers opened. Over 80% of pollen was viable when flowers first opened. Pollen longevity was extended; 58% and 33% of pollen was still viable 8 and 12 days respectively after the flowers opened. Rates of flower opening were slow with only 19-32 flowers opening per day, depending on temperature. More than 80% of flowers had self pollen remaining on their pollen presenters 5 days after the flowers opened. Autogamous pollination did not occur until at least 6 days after the flowers opened. Pollen deposition and fruit production were significantly less on autogamous than open-pollinated inflorescences. Pronounced protandry, extended pollen longevity and slow rates of flower opening in B. spinulosa may have been selectively favoured by inefficient removal of self pollen by floral visitors.

scholarly journals Morphological features of the flower of Symphoricarpos species (Caprifoliaceae) introduced to Ukraine

2020 ◽  
Vol 87-88 ◽  
pp. 22-31
Author(s):  
Olena Bulakh
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Floral Morphology ◽  
Corolla Tube ◽  
Morphological Features ◽  
Common Features ◽  
Scanning Electron

With the help of light and scanning electron microscopy, the features of inflorescences and flowers of six species of the genus Symphoricarpos introduced to Ukraine were studied, and the peculiarities of their structure were specified. Morphological peculiarities of the calyx, corolla, stamens, and style, differentiating S. albus (including S. racemosus and S. rivularis), S. hesperius, S. mollis, S. occidentalis, S. orbiculatus, and S. oreophilus var. utahensis, were determined. The obtained data are important for identification of the species and taxonomy of the genus Symphoricarpos. In particular, the results of our study showed that flowers of S. racemosus, S. rivularis, and S. albus share common features and this supports their synonymy under the name S. albus. Other five Symphoricarpos species showed differences in their floral morphology.Among the important features for identification of Symphoricarpos species introduced to Ukraine, which were not mentioned in available literature sources we can list: the number of flowers in the inflorescence, features of pedicels, shape and features of bracts pubescence, shape of calyx teeth and their pubescence, presence or absence of corolla tube convexity, presence of ovoid projection of anther’s connective, and size of all the floral elements.Symphoricarpos oreophilus var. utahensis has unique features of floral morphology. Its single flowers located in the axis of the leaves on the pendent pubescent pedicels; the calyx is elongated, fusiform; the corolla is narrowly tubular, without a convex at the base; the stamens are shorter than the corolla tubule or rarely of the same length, with a clear ovoid projection on the apex.

FLOWER DEVELOPMENT OF EMPETRUM HERMAPHRODITUM (ERICACEAE), "БОТАНИЧЕСКИЙ ЖУРНАЛ"

2012 ◽  
pp. 475a-486
Author(s):  
N.A. VISLOBOKOV ◽  
D.D. SOKOLOFF ◽  
A.S. KORYAKIN
Keyword(s):  
Flower Development ◽  
Floral Morphology ◽  
Corolla Tube ◽  
Character State ◽  
Electron Microscopic ◽  
Secondary Loss ◽  
Empetrum Hermaphroditum ◽  
Scanning Electron Microscopic ◽  
Electron Microscopic Data ◽  
Scanning Electron

Flowers of most Ericaceae are characterized by pentamery and sympetaly. Empetrum is one of the members of Ericaceae that deviate from this flower groundplan. Due to differences in floral morphology, earlier classifications places Empetrum in a distinct family, Empetraceae belonging to various orders. Perianth of Empetrum is composed by two trimerous whorls of free phyllomes. Different authors interpret it as either simple (with tepals) or double (with sepias and petals). The paper presents scanning electron microscopic data on flower development in Empetrum hermaphroditum. Developmental data suggest that the perianth should be interpreted as double one. Petals are free in anthetic flower and rudiments of corolla tube are not found in early stages of flower development. In this respect, Empetrum differs from some other Ericaceae with free petals in anthetic flowers (such as Rhodonendron tomentosum- Leins, 1964) where rudiments of corolla tube can be traced early in development. In both cases, secondary loss of sympetaly should be assumed. In contrast to another, unrelated genus of Ericaceae bearing flowers with three petals (Tripetaleia-Nishino, 1988) no signs of 'cryptic pentamery' can be traced in flowers of Empetrum. Different patterns of carpel arrangement are documented in Empetrum. Polymerous gynoecium of Empetrum is interpreted as an apomorphic character state derived from a gynoecium isomerous to perianth whorls.

scholarly journals Accurate position exchange of stamen and stigma by movement in opposite direction resolves the herkogamy dilemma in a protandrous plant, Ajuga decumbens (Labiatae)

AoB Plants ◽  
2019 ◽  
Vol 11 (5) ◽  
Author(s):  
Zhong-Ming Ye ◽  
Xiao-Fang Jin ◽  
Jian Yang ◽  
Qing-Feng Wang ◽  
Chun-Feng Yang
Keyword(s):  
Pollen Viability ◽  
Floral Biology ◽  
Pollen Deposition ◽  
High Viability ◽  
Pollen Removal ◽  
Female Phase ◽  
Male Phase ◽  
Accurate Position ◽  
Sexual Interference ◽  
Position Exchange

Abstract Herkogamy is an effective way to reduce sexual interference. However, the separation of stigma and anther potentially leads to a conflict because the pollen may be placed in a location on the pollinator different from the point of stigma contact, which can reduce pollination accuracy. Floral mechanisms aiming to resolve this conflict have seldom been explored. The floral biology of protandrous Ajuga decumbens was studied to uncover how the herkogamy dilemma can be resolved. Flower anthesis was divided into male, middle, female and wilting phases. The positions of stigma and stamen were dissimilar in different flower development stages. We measured the distance of the stamen and stigma to the lower corolla lip at different floral phases, which was the pollinators’ approaching way. The pollen viability, stigma receptivity, pollen removal and pollen deposition on stigma were investigated at different phases. During the male phase, the dehisced anthers were lower than the stigma, located at the pollinators’ approaching way, and dispersed most pollen with high viability. As the flower developed, the anthers moved upwards, making way for pollen deposition during the female phase. Meanwhile, the stigma becomes receptive by moving into the way and consequently was deposited with sufficient pollen. The position exchange of the stamen and stigma created a dynamic herkogamy at the floral phase with different sexual functions. This floral mechanism effectively avoided sexual interference and maintained pollination accuracy. In Ajuga, the movement herkogamy might be of adaptive significance in response to the changes in the pollination environment.

A new species of Canavalia (Leguminosae, Papilionoideae) from Brazil with a specialized corolla suggesting bird pollination

Phytotaxa ◽  
2015 ◽  
Vol 207 (1) ◽  
pp. 115 ◽  
Author(s):  
Cristiane Snak ◽  
Gwilyn Peter Lewis ◽  
Douglas Eduardo Rocha ◽  
Luciano Paganucci Queiroz
Keyword(s):  
New Species ◽  
Systematic Study ◽  
New World ◽  
Floral Morphology ◽  
The Other ◽  
Bee Pollination ◽  
Pollination System ◽  
Bird Pollination ◽  
A New Species

During the development of a systematic study of the species of Canavalia from the New World a new species with floral morphology suggesting a bird pollination system was found, contrasting with the bee pollination pattern of the genus. Canavalia reflexiflora differs from the other species of the genus mainly by its flowers with a reflexed standard; in addition, it also has red flowers, wing and keel petals as long as the standard petal, and an oblong seed with the hilum surrounding nearly half the seed circumference.

Ecology and evolution of sympatric sticklebacks (Gasterosteus): mate choice and reproductive isolation in the Enos Lake species pair

1984 ◽  
Vol 62 (9) ◽  
pp. 1813-1818 ◽  
Author(s):  
Mark S. Ridgway ◽  
J. D. McPhail
Keyword(s):  
Mate Choice ◽  
Reproductive Isolation ◽  
Foraging Behaviour ◽  
Choice Experiments ◽  
Courtship Behaviour ◽  
Field Observations ◽  
Male Courtship ◽  
Species Pair ◽  
Males And Females ◽  
Early Phases

Morphological, genetic, and ecological evidence indicates that two species of sticklebacks (Gasterosteus) coexist in Enos Lake, Vancouver Island. These species are referred to as benthics and limnetics (the names allude to their foraging behaviour and distribution within the lake). Field observations, mate choice experiments, and courtship experiments were conducted to determine if courtship behaviour contributes to reproductive isolation between these two species. Reproductive males and females of both species regularly encounter each other in nature and occasional heterospecific courtships occur. In laboratory mate choice experiments, males and females of both species selected only conspecific mates. In forced courtship experiments, behavioural differences between limnetics and benthics were more pronounced in the early phases of courtship than in the late phases of courtship. Some aspects of male courtship changed with the species of female courted; this suggests that males can distinguish the two types of females. The courtship differences between the two species appear to contribute to their reproductive isolation.

Mechanisms of pollen deposition by insect pollinators

1995 ◽  
Vol 9 (3) ◽  
pp. 304-317 ◽  
Author(s):  
William F. Morris ◽  
Marc Mangel ◽  
Frederick R. Adler
Keyword(s):  
Pollen Deposition ◽  
Insect Pollinators
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