The game of numbers in homeotic flowers of Philodendron (Araceae)

2004 ◽  
Vol 82 (10) ◽  
pp. 1459-1467 ◽  
Author(s):  
Denis Barabé ◽  
Christian Lacroix ◽  
Bernard Jeune
Keyword(s):  
Quantitative Relationship ◽  
Distal Portion ◽  
The Other ◽  
Sterile Male ◽  
Homeotic Transformation ◽  
Bisexual Flower ◽  
Position Information ◽  
Male Flowers ◽  
Female Flowers ◽  
Organ Replacement

In Philodendron, pistillate flowers are initiated on the proximal portion of the inflorescence and staminate flowers are initiated on the distal portion. Between the staminate and pistillate flowers, there is a transition zone consisting of sterile male flowers adjacent to the male zone and a row of atypical bisexual flowers between the sterile male zone and the female zone. The portion of the atypical bisexual flower facing the male zone forms stamens, and the portion facing the female zone develops into an incomplete gynoecium with few carpels. The atypical bisexual flowers of Philodendron are believed to be a case of homeosis where carpels are replaced by sterile stamens on the same whorl. In Philodendron melinonii Brongniart ex Regel, Philodendron pedatum (Hooker) Kunth, Philodendron squamiferum Poeppig., and Philodendron solimoesense A.C. Smith, there is a significant quantitative relationship between the number of carpels and the number of staminodes involved in the homeotic transformation in atypical bisexual flowers. On the other hand, such a significant correlation does not exist in Philodendron fragrantissimum (Hooker) Kunth and Philodendron insigne Schott, and Philodendron callosum K. Krause. There is a one to one organ replacement in homeotic flowers in both P. pedatum and P. squamiferum whereas, in P. solimoesense, an average of 2.56 staminodes replace one carpel. The average number of organs developing on an atypical bisexual flower and the number of organs involved in a homeotic transformation appear to be two independent phenomena. The number of carpels in female flowers is correlated with the maximum total number of appendages (carpels and staminodes) that can develop in atypical bisexual flowers.Key words: development, inflorescence, gradient, position, information.

Developmental morphology of normal and atypical flowers of Philodendron insigne (Araceae): a new case of homeosis

2002 ◽  
Vol 80 (11) ◽  
pp. 1160-1172 ◽  
Author(s):  
Denis Barabé ◽  
Christian Lacroix ◽  
Bernard Jeune
Keyword(s):  
Flower Development ◽  
Distal Portion ◽  
Sterile Male ◽  
Developmental Morphology ◽  
Bisexual Flower ◽  
Male And Female ◽  
Male Flowers ◽  
Morphogenetic Gradient ◽  
Female Flowers ◽  
Scanning Electron

The early stages of development of the inflorescence of Philodendron insigne were examined using scanning electron microscopy. Pistillate flowers are initiated on the lower portion of the inflorescence and staminate flowers are initiated on the distal portion. The male flowers have three to five stamens. The female flowers have a multilocular ovary consisting of three to five locules. A transition zone consisting of sterile male flowers and atypical bisexual flowers with fused or free carpels and staminodes is located between the male and female floral zones. Generally, the portion of the bisexual flower facing the male zone forms stamens, and the portion facing the female zone develops one or two carpels. In P. insigne, the incomplete separation of staminodes from the gynoecial portion of the whorl shows that the staminodes and carpels belong to the same whorl. The atypical bisexual flowers of P. insigne are believed to be a case of homeosis where carpels have been replaced by sterile stamens on the same whorl. However, there is no regularity in the number of organs involved in the homeotic transformation taking place in atypical bisexual flowers. The presence of atypical bisexual flowers may correspond to a morphogenetic gradient at the level of the inflorescence as a whole.Key words: flower, development, gradient, inflorescence.

Development of the inflorescence and flower of Philodendron fragrantissimum (Araceae): a qualitative and quantitative study

2000 ◽  
Vol 78 (5) ◽  
pp. 557-576 ◽  
Author(s):  
Denis Barabé ◽  
Christian Lacroix ◽  
Bernard Jeune
Keyword(s):  
Female Flower ◽  
Distal Portion ◽  
Sterile Male ◽  
Bisexual Flower ◽  
Inflorescence Development ◽  
Male And Female ◽  
Male Flowers ◽  
And Bisexual ◽  
Qualitative And Quantitative Study ◽  
Spatial Discontinuity

The early stages of inflorescence development in Philodendron fragrantissimum (Hook.) G. Don are examined using scanning electron microscopy. Pistillate flowers are initiated on the lower portion of the inflorescence and staminate flowers are initiated on the distal portion. Male flowers have 6-8 stamens (sometimes 5) and female flowers have a multilocular ovary consisting of 6-10 locules. A transition zone consisting of sterile male flowers and bisexual flowers with fused or free carpels and staminodes is also present. This zone is located between the male- and female- flower zones. Generally, the portion of the bisexual flower adjacent to the male zone forms staminodes and the portion bordering the female zone develops an incomplete gynoecium with few carpels. The different floral organs of the bisexual flowers are all inserted in the same whorl. Pistillate and staminate flowers are inserted on the same contact parastichies along the inflorescence; there is no spatial discontinuity between the female zone, the bisexual zone, and the male zone. The presence of bisexual flowers is believed to correspond to a morphogenetic gradient at the level of the inflorescence as a whole. A quantitative analysis of a series of parameters (i.e., length and width of flower types and inflorescence zones) indicates that each zone of the inflorescence has its own particular nature as far as rhythm of growth and geometry are concerned. There appears to be evidence for some form of partitioning in the global development of the inflorescence. The growth of a zone seems to be more variable in size and geometry than that of individual flowers. During later stages of development, the size of the flowers of the intermediate zone, especially the sterile male flowers, increases considerably, until it exceeds that of both male and female flowers.Key words: homeosis, morphogenesis, gradient, allometry, reproduction.

Pengaruh Beberapa Konsentrasi Hyrasil Terhadap Pembungaan Tanaman Melon (Cucumis melo L.)

Agrotek ◽  
2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Liz Yanti Andriyani
Keyword(s):  
Experimental Design ◽  
Sea Level ◽  
Cucumis Melo ◽  
Block Design ◽  
The Other ◽  
Experimental Station ◽  
Randomized Complete Block Design ◽  
Male Flowers ◽  
Cucumis Melo L ◽  
Female Flowers

<em>The objective of the experiment was to observe the best Hydrasil� concentration to the flowering of �melon� to increase the yield of melon </em>(<em>Cucumis melo</em> L.)<em> . The experiment was conducted at Jambi University experimental station, which is located in an altitude of ��35 m above the sea level.� The experimental� design was randomized complete block design with 4 replications and 6 treatment levels of Hydrasil concentration, ie. : H<sub>0 =� </sub>none� Hydrasil treatment, H<sub>1 =� </sub>100 ppm� Hydrasil, H<sub>2 =� </sub>200 ppm�� Hydrasil, H<sub>3 =� </sub>300 ppm� Hydrasil, H<sub>4 =� </sub>400 ppm� Hydrasil, H<sub>5 =� </sub>500 ppm� Hydrasil. The results� showed that Hydrasil concentration� significantly affected number of female �flowers and number of male� flowers per plant. �Hydrasil concentration at� 200 ppm�� gave �more� number of female �flowers �per plant and� less �number of male �flowers per plant than the other treatments.</em>

Organogénie florale des genres Culcasia et Cercestis (Araceae)

1996 ◽  
Vol 74 (6) ◽  
pp. 898-908 ◽  
Author(s):  
Denis Barabé ◽  
Charles Bertrand
Keyword(s):  
Flower Development ◽  
Floral Development ◽  
Intermediate Zone ◽  
The Other ◽  
Other Hand ◽  
Unisexual Flowers ◽  
Male Flowers ◽  
Morphogenetic Gradient ◽  
Female Flowers

The floral development of Culcasia saxatilis, Culcasia tenuifolia, and Cercestis stigmaticus has been analyzed. These two genera possess unisexual flowers without perianth. In these species, the cylindrical inflorescence carry male flowers in the upper part and female flowers in the lower part. In C. tenuifolia, the separation between the female zone and the male zone is very sharp. There is no intermediate zone. In C. saxatilis and C. stigmaticus, we may observe rudimentary bisexual flowers between the two zones. In this intermediate zone, flowers located near the male zone possess male appendages more developped than those located near the female zone. On the other hand, the flowers located near the female zone possess female appendages more developped than those located near the male zone. The results suggest the existence of a morphogenetic gradient in the inflorescence of some species of Araceae. Keywords: morphogenesis, gradient, flower, development, inflorescence.

Pollination of northeastern North American Spiranthes (Orchidaceae)

1983 ◽  
Vol 61 (4) ◽  
pp. 1080-1093 ◽  
Author(s):  
Paul M. Catling
Keyword(s):  
North American ◽  
Cell Elongation ◽  
The Other ◽  
Lower Side ◽  
Terminal Portion ◽  
Stigmatic Surface ◽  
Male Flowers ◽  
Halictine Bees ◽  
Cross Fertilization ◽  
Female Flowers

Most northeastern North American Spiranthes are adapted to pollination by long-tongued bees (e.g., Bombus spp. and Megachilidae). The salient features of this adaptation are (i) a long, flat viscidium which attaches the pollinia readily to the flat rigid galea of the insect's proboscis, (ii) the nectar secreted into the base of the floral tube, (iii) the flowers are protandrous and sequential beginning at the base. In contrast, Spiranthes lucida apparently is pollinated largely by halictine bees. It differs from other northeastern taxa of Spiranthes in (i) having an oval viscidium which attaches the pollinia to the clypeus below the antennae, (ii) having the nectar available on the under side of the column behind the stigmatic surface, and (iii) in lacking protandry. In the characteristically Bombus-pollinated taxa, protandry is accomplished by a change in the position of the terminal portion of the column with respect to the lip, apparently due to cell elongation in both the column and the lip. The present investigation documents protandry in S. cernua var. cernua, S. lacera var. lacera, S. lacera var. gracilis, S. laciniata, S. magnicamporum, S. ochroleuca, S. romanzoffiana, S. tuberosa, and S. vernalis. Bees moving up the spike from the older female flowers to the younger male flowers act initially as pollen donors and later as pollen receivers; thus cross-fertilization is enhanced. Halictines occasionally act as pollinators of characteristically Bombus-pollinated taxa by visiting the flowers upside down so that the pollinia are inconspicuously attached to the lower side of the prementum. Data presently available for northeastern North American Spiranthes fail to establish pollinator specificity as significant in speciation except perhaps with respect to the separation of S. lucida from the other 14 northeastern taxa.

scholarly journals CHARACTERIZATION OF THE GROWTH AND DEVELOPMENT OF COMMERCIALLY AVAILABLE WATERMELON POLLENIZERS

HortScience ◽  
2005 ◽  
Vol 40 (3) ◽  
pp. 872b-872 ◽  
Author(s):  
Peter J. Dittmar ◽  
Jonathan R. Schultheis ◽  
David W. Monks
Keyword(s):  
Growth And Development ◽  
Fruit Production ◽  
The Other ◽  
Flower Production ◽  
Seedless Watermelon ◽  
Early Production ◽  
Male Flowers ◽  
Triploid Watermelon ◽  
Female Flowers

Pollen from triploid (seedless) watermelon (Citrullus lanatas) is nonviable. Diploid (seeded) watermelons are required in seedless watermelon production for pollination and fruit set. In 2004, markets continued to increase for triploid watermelon but decrease for diploid watermelons. Seed companies are commercializing diploid cultivars (pollenizers) specifically designed as a pollen source for triploid watermelon production. The objectives of this research were to characterize the vegetative, floral, and fruit growth and development of these pollenizers. Five cultivars were evaluated: `Companion', `Mickylee', `Mini Pool', `SP-1', and `Jenny'. When measuring the longest vine, `Companion' produced the smallest plants reaching a maximum vine length of 183 cm, 31 days after transplant (DAT). `Mickylee', `Mini Pool', `SP-1', and `Jenny' had similar vine lengths reaching maximum lengths ranging 294–335 cm, 31 DAT. The compact growth of `Companion' is consistent with the shorter node length of 3.8 cm, while the other pollenizers had a node length of 9.9–10.9 cm. `SP-1' produced more male flowers than the other pollenizers beginning 24 DAT and produced 30–40 male flowers per plant per day, 31–55 days after transplant. `Mickylee', `Mini Pool', and `Jenny' produced 9–15 male flowers per plant per day, 24–55 days after transplant. Early production of male flowers by `Companion' was similar to `Mickylee', `Mini Pool' and `Jenny'; however, flower production became the lowest compared with all pollenizer cultivars 24 DAT. `SP-1' produced more female flowers resulting in the most fruit production (4 fruit per plant). In contrast, `Companion' produced the fewest female flowers and produced 2 fruit per vine. `Mickylee' had the largest fruit weighing 5.9 kg, and `SP-1' and `Jenny' produced the smallest fruit weighing 3.1 kg. The use of specific pollenizers may provide the opportunity to customize production for specific cultivars for either early and or late harvests.

A leaky dimorphic sexual system and breeding system characterize a successful island colonist: the reproductive biology of Plocama pendula (Rubiaceae)

2021 ◽  
Author(s):  
Gregory J Anderson ◽  
Julia Pérez De Paz ◽  
Mona Anderson ◽  
Gabriel Bernardello ◽  
David W Taylor
Keyword(s):  
Reproductive Biology ◽  
Canary Islands ◽  
Breeding System ◽  
Reproductive System ◽  
The Other ◽  
Sexual System ◽  
Male Flowers ◽  
Female Flowers ◽  
New Habitats

Abstract Island plants provide special opportunities for the study of evolution and ecology. In field and greenhouse studies we characterized a model reproductive system for Plocama pendula, endemic to the Canary Islands. This species has a complicated and not immediately obvious reproductive system. Pollination is biotic, and all flowers are morphologically hermaphroditic, but half of the plants characteristically bear flowers with nectar, pistils with reflexed stigmatic lobes and pollen-less anthers (i.e. they are functionally female flowers). The other half bear nectar-less flowers with abundant pollen and full-sized pistils that mostly have un-reflexed stigmatic lobes (i.e. they are hermaphroditic flowers functioning mostly as males). However, experiments show these pollen-bearing flowers to be self-compatible. Thus, the functionally male flowers have a breeding system that allows selfing in limited circumstances, but the functionally male flowers produce far fewer fruits than do functionally female flowers. With morphologically gynodioecious, functionally largely dioecious flowers, sometimes capable of selfing, the reproductive system of this species could be labelled as ‘leaky’ in many respects. Thus, we propose that P. pendula has colonized new habitats and persists in substantial populations at least in part because it manifests a reproductive system that is a model for successfully balancing the often-conflicting evolutionary demands of colonization, establishment and persistence.

Développement de l'inflorescence et des fleurs du Philodendron acutatum Schott (Araceae)

1996 ◽  
Vol 74 (6) ◽  
pp. 909-918 ◽  
Author(s):  
Chafika Boubes ◽  
Denis Barabé
Keyword(s):  
Flower Development ◽  
Distal Part ◽  
Chemical Processes ◽  
Bisexual Flower ◽  
Male Flowers ◽  
Morphogenetic Gradient ◽  
Female Flowers

The inflorescence of Philodendron acutatum possesses female flowers in the inferior part and male flowers in the distal part. The male flowers possess from three to six stamens, rarely seven to nine. The female flowers possess a multilocular ovary comprising from 8 to 12 locules. Each locule corresponds to a closed carpel. The stylar canals remain separate up to the upper part of the gynoecium. In this inflorescence, one observes an intermediary zone comprising bisexual flowers with fused or free carpels and stamens, inserted in the same whorl. Generally, the portion of the bisexual flower facing the male zone is formed by stamens, and that facing the female zone is formed by an incomplete gynoecium comprising few carpels. The separation between the two parts of a bisexual flower is generally clear; however, in rare cases, a stamen appears between two carpels, or a carpel between two stamens. Nevertheless, in all cases, the different flower parts are inserted on the same whorl. The presence of bisexual flowers corresponds probably to a morphogenetic gradient at the level of the overall inflorescence. The genes controlling the expression of flower sex are probably governed by chemical processes that act at the level of the overall inflorescence. Keywords: morphogenesis, gradient, flower, development, inflorescence.

Studies in the Alismataceae. XI. Development of the inflorescence and flowers of Wiesneria triandra (Dalzell) Micheli

2000 ◽  
Vol 77 (11) ◽  
pp. 1569-1579
Author(s):  
W A Charlton
Keyword(s):  
Shoot Development ◽  
Annual Plant ◽  
Foliage Leaf ◽  
The Family ◽  
Unisexual Flowers ◽  
Male Flowers ◽  
Female Flowers

Wiesneria triandra (Dalzell) Micheli is an unusual annual plant of the Alismataceae with spike-like inflorescences bearing unisexual flowers. Shoot development follows the sympodial pattern of other Alismataceae, but the cycle is so condensed that initiation of each foliage leaf is followed by inflorescence formation. The plant develops a tufted habit by the formation of an unusual accesory bud adjacent to each inflorescence. Male flowers have three sepals, three petals, three stamens, and usually three carpellodes; female flowers have a similar perianth, three staminodes, and three or more carpels. Up to the first three carpels, floral parts are arranged in alternating trimerous whorls. Additional carpels may occur above and between those of the first whorl. The androecium is particularly unusual for the Alismataceae since it has conventional alternation of stamens with petals rather than the antipetalous pairs of stamens commonly perceived in the family, but the phylogenetic postion of Wiesneria within the family (as revealed by other studies) indicates that the apparently conventional androecium of Wiesneria represents a derived state rather than a primitive one. The unisexual flowers also represent a derived state.

Pollination ecology of Monstera obliqua (Araceae) in French Guiana

2007 ◽  
Vol 23 (5) ◽  
pp. 607-610 ◽  
Author(s):  
Mathieu Chouteau ◽  
Melanie McClure ◽  
Marc Gibernau
Keyword(s):  
French Guiana ◽  
Pollination Ecology ◽  
Lower Portion ◽  
Floral Rewards ◽  
Pollination Mechanisms ◽  
Unisexual Flowers ◽  
Male Flowers ◽  
Female Flowers

Data on pollination ecology of Araceae are still scarce and most concern species belonging to the subfamily Aroideae (García-Robledo et al. 2004, Gibernau 2003, Ivancic et al. 2004, 2005; Maia & Schlindwein 2006). In this subfamily, inflorescences consist of unisexual flowers: female flowers are located in the lower portion and the male flowers are in the upper portion of the inflorescence (Mayo et al. 1997). In the documented neotropical Aroideae, pollinators are nocturnal beetles and pollination mechanisms take place within a floral chamber during a short flowering cycle (generally 24–48 h) with floral rewards (sterile flowers rich in proteins and/or lipids) for the beetle pollinators, the secretion of resin to secure pollen on the pollinator, and the production of heat and odours (Chouteau et al. 2007, García-Robledo et al. 2004, Gibernau & Barabé 2002, Gibernau et al. 1999, 2000, 2003; Maia & Schlindwein 2006, Young 1986).

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