Wayne's Word		Index		Noteworthy Plants		Trivia		Lemnaceae		Biology 101		Botany		Search

Tiwari, A., Vivian-Smith, A., Voorrips, R.E., Habets, M. E.J., Xue, L.B., Offringa, R., and E. Heuvelink. 2011. "Parthenocarpic Potential in Capsicum annuum L. is Enhanced by Carpelloid Structures and Controlled by a Single Recessive Gene." BMC Plant Biology 11:143. Published Online doi: 10.1186/1471-2229-11-143.

General structure of a coiled basket. Bundles of flowering stems (culms) of deergrass (Muhlenbergia rigens) were commonly used by the Cahuilla and other tribes for the foundation (primary coils) of the basket, around which the secondary coils were tightly wrapped. Basketbush (Rhus trilobata) was commonly used for the secondary coils, with intricate designs made from brown coils of rush culms (including Juncus acutus, J. effusus, J. lesueurii and J. textilis). Sometimes the rush culms were dyed to produce various color patterns. Other plants were also used for basketry in the American southwest, including willow (Salix), beargrass (Nolina microcarpa), yucca (Yucca elata) and devil's claws (Proboscidea parviflora).

14. Flower Definitions Papilionaceous: Characteristic flower of the subfamily Papilionoideae within the legume family (Fabaceae). The irregular (zygomorphic) flower is composed of five petals, including one banner petal or standard, two lateral wing petals, and two fused keel petals that enclose the gynoecium and stamens. In some species the ten stamens are all united by their filaments (monadelphous) or one stamen is free and the other nine are united (diadelphous). Note: The legume family is the third largest family of flowering plants with nearly 20,000 described species. Only two families have more species, the orchid family (Orchidaceae) and sunflower family (Asteraceae). The legume family is subdivided into three subfamilies: Papilionoideae, Caesalpinioideae and Mimosoideae. The Papilionoideae have papilionaceous flowers, including many well-known legumes such as sweet pea (Lathyrus), alfalfa (Medicago), bean (Phaseolus), pea (Pisum), clover (Trifolium) and lupine (Lupinus). Flowers of the Mimosoideae consist of showy clusters of numerous stamens arranged in dense spikes or heads, and inconspicuous petals. Examples of this subfamily include mesquite (Prosopis), acacia (Acacia), fairy duster (Calliandra), silk tree (Albizia) and monkeypod (Samanea). The subfamily Caesalpinioideae contains a group of closely-related legumes which have flower buds with their upper petal enveloped by the lateral petals. [In the flower buds of most legumes, the upper petal (banner) is on the outside.] The mature flowers have radial symmetry with five spreading petals, unlike the irregular, pea-shaped (papilionaceous) flowers of subfamily Papilionoideae. The subfamily Caesalpinioideae includes many familiar trees and shrubs including poinciana or bird-of-paradise bush (Caesalpinia), orchid tree (Bauhinia), cassia (Cassia), carob (Ceratonia), palo verde (Cercidium), redbud (Cercis), royal poinciana (Delonix), logwood (Haematoxylum), Jerusalem thorn (Parkinsonia) and tamarind (Tamarindus). Actinomorphic (Regular): Flower with radial symmetry because the perianth segments (petals and sepals) are similar in size and shape. This type of flower is divisible into equal halves along more than one plane. Zygomorphic (Irregular): Flower with bilateral symmetry because the perianth segments are dissimilar in size and shape. This type of flower is divisable into equal halves along only one plane. Superior: Refers to a ovary that is above the attachment of the petals, sepals and stamens, and is free from the receptacle. A perigynous ovary within a cup-shaped hypanthium is superior if it is completely free from the outer hypanthium. Inferior: Refers to an ovary that is below the attachment of the petals, sepals and stamens. The hypanthium may be fused to the ovary wall or attached to the top of the ovary. The ovary of an apple is inferior because it is fused with a thick, fleshy hypanthium. Stamens, petals and sepals arise from the top of the hypanthium (on top of the apple). Hypogynous: Below the gynoecium, referring to perianth segments and stamens that are attached directly to the receptacle at the base of an ovary. Perigynous: Around the gynoecium, referring to perianth segments and stamens that are attached directly to the rim of a cup-shaped hypanthium that surrounds the ovary. In this case, the ovary is completely free from the outer hypanthium. Epigynous: Above the gynoecium, referring to perianth segments and stamens that are attached to the top of the ovary or to the rim of a cup-shaped hypanthium that is attached to the top of the ovary. Hypanthium: A cup-shaped structure surrounding the ovary and formed by a fusion of the bases of the perianth segments (petals and sepals). Some references state that the hypanthium may also contain tissue from the receptacle. In the apple (a pome), the thickened, fleshy hypanthium is fused with the ovary wall (seed-bearing core). When you eat an apple, you are primarily biting into the hypanthium tissue. Dioecious: A species population containing male plants bearing only male (staminate) flowers and female plants bearing only female (pistillate) flowers. [e.g. cottonwoods (Populus), willows (Salix) and marijuana (Cannabis). This term is incorrectly applied to individual flowers. Monoecious: A species population composed of plants that produce both male (staminate) and female (pistillate) flowers on the same individuals. This term is incorrectly applied to individual flowers. Gynodioecious: A species population containing plants that produce bisexual (perfect) flowers, and plants that produce only female (pistillate) flowers. [In the common edible fig (Ficus carica), the "male" caprifig produces syconia containing unisexual male and female flowers, while the "female" edible fig produces syconia containing only female flowers.] See following NYBG definition. NYBG Steere Herbarium Definition of Gynodioecious: Sexual condition of a species that bears pistillate flowers on some plants and bisexual flowers or staminate flowers as well as pistillate flowers on other plants. The important word here is "or" rather than "and" [e.g. Fig (Ficus) & Mulberry (Morus)]. Gynomonoecious: A species population containing plants that produce bisexual (perfect) flowers and female (pistillate) flowers on the same individuals. There are no functional unisexual male (staminate) flowers. Gynomonoecious. NYBG Steere Herbarium Definition: Referring to a sexual condition of a species that bears pistillate flowers and bisexual flowers on same plants. Androdioecious: A species population containing plants that produce bisexual flowers and plants that produce only male flowers. [e.g. Certain species of nightshades in the genus Solanum.] Andromonoecious: A species population containing plants that produce bisexual flowers and male (staminate) flowers on the same individuals. There are no functional unisexual female (pistillate) flowers. Polygamous: A species population containing plants that produce bisexual (perfect) and unisexual (imperfect) flowers on the same individual. Not to be confused with human polygamy, or having two or more wives or husbands at the same time. Note: Sometimes the unisexual flowers may contain the rudimentary parts of the opposite sex. [e.g. Toxicodendron diversilobum, better known as poison oak; also species in the Asteraceae with radiate and discoid heads. ] Polygamodioecious. NYBG Steere Herbarium Definition: Referring to the sexual condition of a species that bears (male) staminate and bisexual (perfect) flowers on some plants and female (pistillate) and bisexual flowers on other plants. Polygamomonoecious. NYBG Steere Herbarium Definition: Referring to the sexual condition of a species that bears staminate, pistillate, and bisexual flowers on the same plant. Same as trimonoecious. Complete: Flower with all four characteristic parts present, including the sepals (calyx), petals (corolla), stamens (androecium) and pistil (gynoecium). Incomplete: Flower that is lacking one or more of the four characteristic parts, including the sepals (calyx), petals (corolla), stamens (androecium) and pistil (gynoecium). For example, apetalous flowers are incomplete flowers lacking petals. Perfect: A bisexual flower with functional stamens (androecium) and a functional pistil (gynoecium). Imperfect: A unisexual flower with only one type of functional sex organ. For example, staminate flowers are imperfect flowers that contain only stamens, while pistillate flowers contain only pistils (gynoecia). Chasmogamous: Flowers that open and expose the stamens and styles to cross pollination by wind, water, birds and insects. Cleistogamous: Flowers that do not open and are self pollinated. Cleistogamy insures that a plant produces seeds, even if conditions are unfavorable for wind or insect pollination. Cleistogamy occurs in many different and unrelated plant families, including violets (Violaceae), rushes (Juncaceae) and grasses (Poaceae). Some water lilies (Nymphaeaceae) produce cleistogamous flowers that do not open in rainy weather. The pollen of many angiosperms is damaged by water. In sunny weather, the flowers are open (chasmogamous) and pollinated by insects. There are unconfirmed reports of insect pollinated plants in Timbuctu that produce cleistogamous flowers when the ground temperature is too hot for crawling insects. A Wildflower From Europe With Cleistogamous Flowers Viviparous: Seeds and spores that germinate into small plantlets (bulblets) while still attached to the parent plant. Apomixis: Seed development without fertilization. The offspring develop from unfertilized eggs which are often clones of each other. In general there are two main types of apomixis: Parthenogenesis and agamospermy. Parthenogenesis (Agamogenesis): A haploid or diploid egg cell develops into an embryo. Contrary to some authors, parthenogenesis does not always result in genetically identical clones. If the haploid cells are formed by normal meiosis (as in the queen honey bee), crossing over during Prophase I of meiosis may result in some genetic variability. Crossing over is discussed at on the Wayne's Word Mitosis vs. Meiosis Page. Agamospermy: Term applied to an embryo that arises from tissue surrounding the embryo sac. If this involves cells of the nucellus or inner integument it is called a nucellar embryo. Nucellar embryos are chromosomally identical to the sporophyte parent. They are essentially clones of the female parent. Apomictic seeds allow propagation of choice edible fig cultivars (female trees) without the transmission of viruses through cuttings (need reference here). Mangosteen seeds (Garcinia mangostana) typically contain nucellar embryos and are used to propagate clones of this delicious tropical fruit tree. Parthenocarpic: Term applied to the development of the ovary of a flower into a fruit without fertilization. Fruits that develop parthenocarpically are typically seedless. Some seedless fruits come from sterile triploid plants, with three sets of chromosomes rather than two. The triploid seeds are obtained by crossing a fertile tetrapolid (4n) plant with a diploid (2n) plant. When you buy seedless watermelon seeds, you get two kinds of seeds, one for the fertile diploid plant and one for the sterile triploid. The triploid seeds are larger, and both types of seeds are planted in the same vicinity. Male flowers of the diploid plant provide the pollen which pollinates (but does not fertilize) the sterile triploid plant. The act of pollination induces fruit development without fertilization, thus the triploid watermelon fruits develop parthenocarpically and are seedless. Most bananas purchased at your local supermarket come from sterile triploid hybrids. The fruits develop parthenocarpically and are seedless. Parthenocarpy can be induced by growth hormones such as gibberellic acid (GA3) in which the ovaries mature without fertilization. Grape cultivars such as 'Thompson Seedless' are treated with gibberellic acid to order to produce larger fruits with longer internodes. The bunches have wider spaces between the grapes and better air circulation, reducing their susceptibility to fungal diseases and rotting within the bunch. Contrary to some references, 'Thompson Seedless' grapes are not parthenocarpic because fertilization does occur, but the ovules fail to develop into seeds within the maturing fruit. In cultivated figs, parthenocarpy generally refers to the development of the ovaries of female flowers within the syconium into drupelets without fertilization. The syconium is the structure that you typically associate with an edible fig fruit; however, it is really a flask-shaped inflorescence lined on the inside with numerous unisexual flowers. The actual botanical fruits (called drupelets) develop within the syconium. Since the entire syconium enlarges and ripens into a juicy, sweet morsel, it is often referred to as a fruit. The female flowers are pollinated by a tiny female fig wasp that enters the syconium through a pore called the ostiole. According to W.B. Storey (Advances in Fruit Breeding, 1975), there are 2 genetically determined forms of parthenocarpy: stimulative and vegetative. Stimulative parthenocarpy involves the insertion of the wasp's ovipositor down the stylar canal into the ovary of short style flowers. It can also be induced by blowing air into the syconium, or by spraying the syconium with a plant growth regulator. The mature drupelets may contain a wasp (if an egg was laid in the ovary) or it may be empty. Vegetative parthenocarpy involves the formation of drupelets without any external stimulation, and is responsible for the hollow drupelets inside common figs such as "black mission," "kadota," and "brown turkey." [Some authors use the term parthenocarpy to describe the ripening of seedless fig syconia on the tree without any pollination or fertilization.] Monocarpic: A plant that flowers and bears fruit only once and then dies. Century plants (Agave) and some yuccas (Yucca whipplei) bloom after 8-10 to 20 years or more and then die. Most varieties of bamboos in cultivation are clones derived from a single plant that may be traced back to one seed. This may explain why some cultivated bamboos have the same flowering cycle and mortality as populations on different continents. By far the majority of bamboo species are not monocarpic, i.e. they do not flower gregariously and then die. Monocarpous: A gynoecium composed of one carpel. Strategies For Insuring Cross Pollination: Cross Pollination: The transfer of pollen from the anthers of Plant A to the stigmas of Plant B. [Self pollination is the transfer of pollen from the anthers of Plant A to the stigmas of Plant A.] Cross pollination provides greater genetic variation, the raw material for evolution. Dioecious Species: Populations with separate male (pollen-bearing) and female (seed-bearing) plants must be cross pollinated. Approximately 3-4 percent of all flowering plants are dioecious. Although dioecism favors cross pollination, there is reduced seed production because only half of the population (the female plants) bear seeds. See Photos Of The Dioecious Surf Grass Maturation Sequence Of Anthers & Stigma: The pollen-bearing anthers and receptive stigmas in the flowers of a given plant mature at different times. Therefore, pollination must occur between the anthers and stigmas of different individuals within the population that have the same maturation sequence. Protogynous Flowers: The stigma is receptive before the anther releases pollen. [e.g. Plantains, magnolia, avocado, figs (Ficus) and wolffia.] A Protogynous Wolffia Plant In Full Bloom Pollination Of Edible Fig By Its Symbiotic Wasp Protandrous Flowers: The stamens mature and release pollen before the stigma is receptive. [e.g. Sunflower, cornflower, sage (Salvia) and verbena.] Heterostyly: A population containing plants with flowers containing high anthers & low styles, and plants with flowers containing high styles and low anthers. Cross pollination is favored when pollen is transferred from high anther flowers to high style flowers. [e.g. primose (Primula). Thigmotropic Stigma: The two-lobed stigma of red bush monkeyflower (Mimulus puniceus) is sensitive to touch and rapidly closes if touched by your finger or the bill of an incoming pollinator. This action decreases the chance of self pollination and favors cross pollination. When the bill or head of a hummingbird enters the blossom and touches the stigma it immediately closes. Pollen carried by the bird is trapped within the closed stigma lobes. As the bird probes for nectar deep in the corolla it also picks up fresh pollen from the anthers. But when it leaves, there is little chance of this newly acquired pollen touching the stigma because it is already closed, thus averting any self pollination. See The Red Bush Monkeyflower In Local Hills Self-Incompatible Pollen: In the androdioecious flowers of certain nightshades (Solanum), the pollen in plants with bisexual flowers is sterile. This infertile (inaperturate) pollen does not have apertures when viewed under a microscope and is non-stainable. Without fertile pollen, the bisexual flowers are functionally female. Male plants in the population with functional staminate flowers produce viable pollen which cross pollinates with the "female" plants. Flynapping Arums & Dutchman's Pipe: The arum family (Araceae) is characterized by a phallus-like inflorescence called a spadix bearing clusters of protogynous, pistillate flowers below the staminate flowers. The spadix is often enveloped by a colorful, funnel-like spathe. A truly remarkable arum (Helicodiceros muscivorus) with an ingenious fly trap is native to the rocky Mediterranean islands of Sardinia and Corsica. With a stench reportedly as strong as a sheep carcass, blow flies are lured into a pitch dark, fetid chamber at the base of the funnel-like spathe. Carrying pollen from another plant, they inadvertently pollinate the receptive female flowers at the base of the chamber. Unable to escape from the chamber due to a dense rosette of stiff hairs, the flies remain prisoners until the male flowers above the stiff hairs start to release pollen. Then the barricade of hairs wilts and the flies are able to escape, getting dusted with pollen as they leave the damp and putrid-smelling chamber. The European Dutchman's pipe (Aristolochia clematitis), a member of the birthwort family (Aristolochiaceae), has a similar ingenious method of incarcerating insects until its male flowers shed pollen. See The Remarkable Stinking Arums See The Remarkable Dutchman's Pipe Contact Pollination: This method of pollination involves the male and female flowers of dioecious species (e.g. Vallisneria) and the male and female organs of bisexual, protogynous species (e.g. duckweeds of the Lemnaceae). The male flowers of Vallisneria and the pollen-bearing plant bodies of bisexual duckweeds (e.g. Lemna and Wolffia) are pushed along the water surface where they bump into receptive female flowers of Vallisneria and the gynoecia of bisexual duckweeds. Contact Pollination In Ribbongrass (Vallisneria) Contact Pollination In The Duckweed (Lemna gibba)

Go To The Diversity Of Flowering Plants Return To WAYNE'S WORD Home Page Return To NOTEWORTHY PLANTS Page Go To Biology GEE WHIZ TRIVIA Page Go To The LEMNACEAE ON-LINE Page