The flowers usually possess nectar or edible pollen. Pollen transport in flow fields and capture by stigmas. (vi)   The flowers are well exposed in the air. Pollination through the agency of animals is known as zoophily. Flow chamber observations of the filamentous pollen of Zostera marina L. (Potamogetonales) revealed that pollen rotated and moved toward inflorescences where they were captured by stigmas. 1. In these flowers cross pollination is the only means for fertilization and production of seeds. Hydrophily is of two types: Hypohydrophily Plants which are pollinated inside the water. For example, a single flower of Cannabis produces, 5,00,000 pollengrains. The nectar is chiefly made of sugars and provides a sweetdrink to the bird. Gynoecium matures earlier than androecium eg. Ex: Zostera, Vallisneria Characters: Flowers are small and inconspicuous. Nectar and odor are absent. Examples: Vallisneria (Ribbon weed) -Epihydrophily: (Pollination over the surface of water) is observed in Vallisneria. eg., Hibiscus sps; Gloriosa superba, etc. They have similar specific gravity as that of water; thus float beneath the surface of water. The birds visit a large variety of flowers such as Bombax (red silk cotton), Erythrina (Coral tree), Callistemon (Bottle brush), Bignonia, Agave, etc. | i.e. | | | tallest flower (6 ft) amorphophallus. fly pollinated - rotten meat smell. ... beetles lay eggs and pollinate. Zostera, Ceratophyllum, Najas, etc. Media Articles ... beetles lay eggs and pollinate. (ii) Hypohydrophily:- When the pollination takes– place inside the water is called hypohydrophily. Bees are the chief visitors of flowers and they obtain both nectar and pollen from the flowers. It has already been stated that pollination, in a vast majority of cases, involves some agent. The lower lip provides platform for the visiting insect and the upper lip is just like a hood which protects the floral organs. Specific gravity is found in pollen grains so they remains suspended Hydrophily is of two types, hypohydrophily and epihydrophily. The flowers they visit are large, dull-coloured and have a strong scent. (ii) Biotic agents (a) Entomophily : When pollination is brought about by the agency of insects, it is known as entomophily or insect pollination. Anthers and stigmas are commonly inserted. 3. The upper fertile lobes are sheltered in the upper lip of corolla. Accordingly, self pollination is of … It is the base of any plant diversity. vallisneria. Variations caused due to cross pollination may result in production of disease resistant plants. (vii) The stigmas are large, well-exposed, hairy, feathery or branched to catch the air-borne pollen grains. Notes Such plants set seeds only after cross pollination. It is further divided into two parts: Epihydrophily: Pollination occurring on the water surface. Vallisneria is epihydrophily which occurs through the surface of the water. Reproduction: Questions 53-60 of 119. Vallisneria is epihydrophily which occurs through the surface of the water. The common examples of wind pollinated flowers are - grasses, sugarcance, bamboo, coconut, palm, date palm, cannabis (bhang), maize etc. Some of the common chiropterophilous plants are - Kigelia pinnata (Sausage Tree), Adansonia (Baobab Tree), Bauhinia megalandra, Anthocephalus (Kadam Tree), etc. hypohydrophilly (3) zostera, najas, ceratophyllum. Epihydrophily : Plants which are pollinated outside the water. Cross Pollination involves the transfer of pollen grains from the flower of one plant to the stigama of the flower of another plant. The flowers are usually brightly coloured and have specific odour. Contrivances for cross pollination : Nature favours cross  pollination. Sample Papers (b) Hydrophily : When the pollination takes place through the agency of water, it is known as hydrophily. Salvia is excellent example of insect pollination is which pollination occurs by lever or turn pipe mechanism. (iv)  Pollen grains are small, light, dry, dusty and sometimes winged (or saccate) so that they are easily blown away to long distances (upto 1300 km). Refund Policy, You need to login to perform this action.You will be redirected in iii)    Several crop plants (such as Mustard, Safflower, Sunflower, Clover, Cucurbits), give significantly higher yields if bees are available and cross pollination is allowed to occur. Pollen grains are long, without exine, heavier than water , sink down to meet stigma of female flowers. The insects visit the flowers for nectar, edible pollen grains or shelter. Hypohydrophily :Plants which are pollinated inside the water e.g.Zostera, Ceratophyllum, Najas, etc. vallisneria. e.g., Anemone nemarosa (fruit). The mature anthers break at the base, mount to the surface of water and dehisce there. Anemophilous flowers are small and inconspicuous with long and versatile stamens. (i) Epihydrophily:- When the pollination takes place on the surface of water is called epihydrophily e.g. In some other flowers, the pollens are held together to form pollinia which can only be carried away by insects. Hypohydrophily :Plants which are pollinated inside the water e.g.Zostera, Ceratophyllum, Najas, etc. The upper arm is long and curved. Unisexuality can be of two types : (ii) Dichogamy : In bisexual flowers, when two sexes mature at different intervals and thus avoid self pollination is known as dichogamy. Specific gravity of pollen grains is equal to that of water, so they float on water. • All aquatic plants are not hydrophilous. FAQ Examples: Vallisneria (Ribbon weed) They havepollen sacs or pollen baskets for collecting pollen. It is also called Xenogamy. Some taxa have been reported as being plants that pollinate at or just above the water surface (epihydrophily): Zostera marina (Cox et al. (iv) Herkogamy : In some bisexual flowers where the stigma and anthers mature at the same time, self pollination is avoided by some sort of barrier. Latest … New and healthier varieties are not formed. Arisaema (aroid; snake plant) is often visited by snails. Flowers are bisexual but the essential organs, the stamens and stigmas, are arranged in the flower, in such a way that self pollination becomes mechanically impossible. e.g. (c) Chiropterophily : It is a mode of pollination performed by bats. Anthers are usually versatile. Pollen and stigma of the flower mature at different times to avoid self-pollination. Agents for cross pollination : Cross pollination involves external agents for the transfer of pollen grains of one flower to the stigma of another flower. The lower arm of connective is short and bears the sterile lobe of anther. Hydrophily occurs only in a few aquatic plants. Copyright © 2018-2021 BrainKart.com; All Rights Reserved. which attract the birds from long distances. e.g.Vallisneria (Ribbon weed). | Transfer of pollen grains shed from anther to stigma of a pistil is called pollination.Flowering plants have evolved an amazing array of adaptations to achieve pollination.Plants can be pollinated by 3 kinds. Epihydrophily is uncommon in angiosperms. Geitonogamy involves two flowers but these belong to the same parent plant. All unisexual flowers and a large number of bisexual flowers are naturally cross pollinated. Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail, Cross Pollination (Xenogamy, Allogamy) - Sexual Reproduction. Large amount of pollen grains are wasted. The ornithophilous flowers are characterized by the following adaptations: i) The flowers are usually large in size. Anthers and stigmas are commonly inserted. I. It bears the fertile lobe of anther. e.g., Kigelia pinnata (Sausage tree), Adansonia (Baobab tree), Bauhinia megalandra, Anthocephalus (Kadam tree), etc. Pollination is defined as the process of transfer of pollen grains from anther to the stigma of the same flower or of different flower of the same species. Ncert Solutions marine Zostera (Zosteraceae). Jobs For example, a single flower of. | 403). Zoophily. (e) Myrmecophily : Pollination by ants. Some classic examples are as follows : The genus Salvia belongs to family Labiatae (Mint family) in which the gamopetalous corolla is two-lipped (bilabiate). amorphophallus. e.g., Sugarcane, Maize, Wheat, Bamboo, Pinus, Papaya, Grasses, Typha, Datepalm, Coconut, Mulberry, Chenopodium, etc. (v)  Pollen grains of anemophilous flowers are produced in huge quantities. Pollen grains are light and non-wettable due to presence of mucilage cover. Cross pollination brings about genetic recombination and production of new varieties (variations). Epihydrophily : When the pollination takes place on the surface of water, i.e., Vallisneria and Ruppia. Flowers are brightly coloured and produce plenty of nectar and large quantities of pollen. The flowers they visit are large, dull-coloured and have a strong scent. In Zostera marina, the pollen grains are elongated (upto 2,500 mm), needle like and without exine. The flowers of some plants have different lengths of stamens and styles so that self pollination is not possible eg. rafflesia. fly pollinated - rotten meat smell. Androecium matures and shed pollen gynoecium eg. Hydrophily is of two types, hypohydrophily and epihydrophily. The flowers are usually large in size. Each stamen has a short filament and an elongated curved connective. When the male flowers are mature, the individual anthers break off and settle through the water until they reach a groove near the stigma of a female flower, leading to pollination. In certain plants, they are produced above the foliage before the appearance of new leaves. When stamens mature earlier than the stigma, it is known as protandry and the flowers are called protandrous e.g., Coriander, Jasmine, Sunflower, Lady’s finger, etc. e.g. In Vallisneria male and female flowers are produced on separate plants. The main contrivances ensuring cross pollination are as follows : (i) Diclincy or Unisexuality : In unisexual flowers stamens and carpels are found in different flowers. Pollination. It is of two types : (1) Self pollination : This process involves the transfer of pollen grains from the anthers to the stigma of the same flower or of another flower borne by the same plant. • Pollination takes place through water. (c) Cleistogamy : Some plants never open to ensure complete self-pollination. Franchise COX, P. A., LAUSHMAN, R. H. & RUCKLESHAUS, M. H., 1992. As a bee visits the young flower and moves inward in search of nectar, its head pushes the sterile plate which brings down the fertile anther lobes to strike against its back. The two sterile lobes jointly form a sterile plate of tissue which is placed at the mouth of corolla tube and partly blocks the path of the visiting insect. (2) Cross pollination : Cross pollination involves the transfer of pollen grains from the flower of one plant to the stigma of the flower of another plant. Surface and submarine pollination in the seagrass Zostera marina L. Hydrophilous plants can be divided into three ecological categories depending upon whether their pollen is transported above, on, or under the water surface. Stigma is long, sticky but wettable. 6. Eg:Zostera,Ceratophylum,Hydrilla b)EPIHYDROPHILY: The bird can derive about half of its body weight of nectar in a single day. | Vallisneria and Ruppia. In many aquatic plants with emergent flowers, pollination occurs by wind or insects, e.g., Lotus, Water Lily, Water Hyacinth. Biotic agents (a) Entomophily : When pollination is brought about by the agency of insects, it is known as entomophily or insect pollination. Epihydrophily :Plants which are pollinated outside the water. The pollengrains are deposited upon the back of the bee. The members of Hydrocharitaceae almost pollinate by hydrophily only. | | Epihydrophily takes place over the surface of water, e.g., Vallisneria. It is also called Xenogamy. Why Studyadda? The pollination which takes place by means of water is known as hydrophily.It occurs only in aquatic plants.however,many aquatic plants with emerged flowers have other modes of pollination. Stigma is long, sticky but wettable. Hydrophily occurs only in some 30 genera of mostly monocots e.g., Vallisneria, Zostera, Ceratophyllum, etc. The liberated pollen germinate and sink in water. The flowers show following contrivances : (v) Self sterility or Incompatibility : When pollen grain of an anther do not germinate on the stigma of the same flower, then such flower is called self sterile or incompatible and this condition of flower is called self sterility, intraspecific incompatibility or self incompatibility. Vallisnaria -epihydrophily. In bisexual flowers, the stamens are generally numerous. largest inflorescence (12 ft) amorphophallus. The cleistogamous flowers are bisexual small, inconspicious, colourless and do not secrete nectar. Following compatible pollination, the pollen grain germinates on the stigma to produce a pollen tube through one of the germ pores. All aquatic plants are not hydrophilous some are anemophilous e.g., Potamogeton, Myriophyllum or Entomophilous e.g., Alisma, Lotus. Some examples of water pollinated plants are Vallisneria and Hydrilla which grow in fresh water and several marine sea-grasses such as Zostera. This condition is called cleistogamy, e.g., Commelina bengalensis, Oxalis, Viola, etc. • All aquatic plants are not hydrophilous. Hydrophily is of two types : (a) Entomophily : When pollination is brought about by the agency of insects, it is known as entomophily or insect pollination. Sometimes ants take their food or shelter on some trees such as, The pollination performed by any type of animal is called. This process is known as Hydrophily. Stigma is long, sticky but wettable. They have, The flowers are large or if small they are grouped into inflorescence. Epihydrophily : Plants which are pollinated outside the water. (Gk. Surface and submarine pollination in the seagrass Zostera marina L. Hydrophilous plants can be divided into three ecological categories depending upon whether their pollen is transported above, on, or under the water surface. Xenos = Strange, gamos = marriage) or allogamy (gk, allos = other, gamos = marriage. Ornis = bird, philein = to love) is a mode of pollination performed by birds. It is also called xenogamy. In Zostera marina, the pollen grains are elongated (up to 2,500 mm), like needle and without exine. Amazing Facts The act of pollination is not performed by all the birds except a few. II. Pollen grains of anemophilous flowers are produced in huge quantities. | The flower of orchid ophrys resemble in shape colour and odour to female wasp of colpa aurea (mimicry). The stigmas are large, well-exposed, hairy, feathery or branched to catch the air-borne pollen grains. Stigma is long, sticky but wettable. Each flower of Adansonia (Baobab Tree) has 1500-2000 stamens. They have the same specific gravity as that of water. male and female flowers occur on separate plants. Gloriosa superba : The style is reflexed away from the stamens. ... Epihydrophily and Hypohydrophily. About Thus facilitate cross pollination. Hydrophily is a fairly uncommon form of pollination whereby pollen is distributed by the flow of waters, particularly in rivers and streams. Zostera is mainly called as marine eelgrass and pollinated by water method . Zoophily. Epihydrophily : Pollination occurs on the surface of water. Pollination carried out through water is hydrophily. This process is known as Hydrophily. : The style is reflexed away from the stamens. A mixed mode of submarine and surface hydrophilous pollination occurs in the seagrass Zostera marina L. Hypohydrophily : Plants which are pollinated inside the water e.g., Zostera, Ceratophyllum, Najas, etc. …unusual in that they have underwater pollination. Chiropterophilous flowers produce abundant pollen grains and secrete more nectar than the ornithophilous flowers. Ackerman J. Pollination followed by fertilization and consequently development of fruit and seed not only produces foods but also is one of the important building block of crop improvement. When the male flowers are mature, the individual anthers break off and settle through the water until they reach a groove near the stigma of a female flower, leading to pollination. hypohydrophilly (3) zostera, najas, ceratophyllum. eph/epihydrophily. The pollen grains are released inside the water. Pollen grains are without exine and often elongated. The birds visit a large variety of flowers such as Bombax (Red Silk Cotton), Erythrina (Coral Tree), Callistemon (Bottle Brush), Bignonia, Agave, ete. much more widespread pollination systems. The important pollinating insects are bees, butterflies, moths, wasps, bettles etc. It is a very rare type of pollination, even in aquatic plants. Biotic agents (a) Entomophily : When pollination is brought about by the agency of insects, it is known as entomophily or insect pollination. Cross Pollination involves the transfer of pollen grains from the flower of one plant to the stigama of the flower of another plant. The bird can derive about half of its body weight of nectar in a single day. https://www.studyadda.com i.e. There are two main groups of agents : (i) Abiotic agents like wind and water (ii) Biotic agents which include animals of different types such as insects, birds, bats, snails, etc. When the pollen-dusted bee visits older flower (with protruded bilipped stigma), its back rubs against the mature stigma bringing about the pollination. Anthers are usually versatile. They have tubular or funnel-shaped corollas. Pollination carried out through water is hydrophily. The second one is abiotic agent like wind and water. Epihydrophily : When the pollination takes place on the surface of water, i.e., Vallisneria and Ruppia. Androecium matures and shed pollen gynoecium eg. Cross pollination always occurs when the plants are unisexual and dioecious. The mature anthers break at the base, rise to the surface of water and dehisce there. Entomophilous flowers produce a small amount of pollen which has a spinous and sticky exine due to presence of pollenkitt. Hypohydrophily is true hydrophily which occurs below the surface of water. eg., Papaya, some cucurbits etc. water is a regular mode of transport for the male gametes among the lower plant groups such as algae, bryophytes, and pteridophytes. 2. tallest flower (6 ft) amorphophallus. It usually occurs in plants which show monoecious condition (unisexual, male and female flowers are borne on the same plant). inhibiting pollination is therefore likely to be the bursting or death of pollen grains, rather than their submergence. At maturity male flowers are … Yucca is pollinated by Pronuba (= Tegaticula) yuccasella which passes its larval stage inside the ripening ovary. Epihydrophily: Pollination occurs on the surface of water. Zostera marina is a submerged marine sea grass and pollination takes place under water. With the help of the water, the pollens come in contact with the female flowers and the pollination is achieved. Pollination through the agency of animals is known as zoophily. ii) The flowers are brightly coloured (such as red, yellow, orange, blue, etc.) Vallisneria) (b) Hypohydrophily ( inside water) e.g. It involves two main groups of agents – biotic agents which include animals of different types such as insects, bird, bats, snails etc. Xenos = Strange, gamos = marriage) or allogamy (gk, allos = other, gamos = marriage. The bats are nocturnal flying mammals which move swiftly and transport pollen grains to long distances, sometimes over 30 kms. The members of Hydrocharitaceae almost pollinate by hydrophily only. The pollen grains are long, needle like. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Hydrophilous species fall into two categories: Those that distribute their pollen to the surface of water. Two general, but sometimes rather arbitrary, forms of hy drophily are recognized: 1) epihydrophily; pollination via pollen transport at the water surface (two-dimensional), and 2) hypohy drophily; pollination via pollen … POLLINATION Two types of pollination Self-pollination Cross-pollination 4. • Pollination takes place through water. (iii)  When flowers are unisexual, male flowers are more abundant than female flowers. While sinking, they come in contact with stigma of female flowers to produce pollination. Example: Zostera. The important characteristics of insect pollinated flowers are as under. The dioecious plant Vallisneria having strap-shaped leaves grow in the mud at the bottom of stagnant water (Fig. The flowers usually possess nectar or edible pollen. (ii)  Calyx and corolla are either reduced or absent. While sinking, they come in contact with stigma of female flowers to effect pollination. Pollination in Vallisneria spiralis: It is a dioecious, submerged and rooted hydrophyte. Ceratophyllum, Najas Zostera and Hydrilla. It occurs in totally submerged plants and their pollen grains are water borne. In bisexual flowers, the stamens are generally numerous. The most common bird pollinators are Sun bird, Humming bird, Crow, Bulbul, Parrot, Mynah, etc. Flowers are bisexual but the essential organs, the stamens and stigmas, are arranged in the flower, in such a way that self pollination becomes mechanically impossible. Bajra, Aristolochia etc. Example: Vallisneria. The nectar is chiefly made of sugars and provides a sweet drink to the bird. (Gk. Solved Papers The pollen grains are long, needle like. Nectar and odor are absent. Start studying pollination. Pollination types: Fig: Types of Pollination. It is further divided into two parts: Epihydrophily: Pollination occurring on … Examples: Zostera Ceratophyllum Najas Epihydrophily Plants which are pollinated outside the water. a. Epihydrophily: Pollination occurs at the water level. Hypohydrophily has also been reported in the mono-generic Callitrichaceae. The flowers are usually brightly coloured and have specific odour. Eg:Zostera,Ceratophylum,Hydrilla b)EPIHYDROPHILY: Stigmas are usually unbranched and may be flat or lobed. Ornithophily (Gk. Nectar and odor are absent. When they reach the stigma, they oil around it and germinate. It is described as epihydrophily. The main floral characteristics which facilitate cross pollination are. The pollen grains can, therefore, float below the surface of water. Copyright © 2007-2020 | plant to the stigama of the flower of another plant. The flowers are protandrous. Cross Pollination involves the transfer of pollen grains from the flower of one. Example: Vallisneria. The pollination performed by any type of animal is called Zoophily. water is a regular mode of transport for the male gametes among the lower plant groups such as algae, bryophytes, and pteridophytes. Pollen grains are light and non-wettable due to presence of mucilage cover. 3 sec, OTP has been sent to your mobile number and is valid for one hour. Notification Hydrophily is of two types: Hypohydrophily Plants which are pollinated inside the water. Calyx and corolla are either reduced or absent. Ex: Zostera, Vallisneria Characters: Flowers are small and inconspicuous. amorphophallus. The process of transfer of pollen grains, from an anther to the stigma of the same flower or of different flower. SELF POLLINATION It is the transfer of pollen grains from the anther of a flower to the stigma of either the same or genetically similar flower. e.g., Rose, Tobacco, Crucifers, etc. The insects visit the flowers for nectar, edible pollen grains or shelter. Humming bird pollinates while hovering over the flowers and sucking nectar. e.g., Oxalis. Sometimes ants take their food or shelter on some trees such as Mango, Litchi, South American Acacia and so on. e.g.Vallisneria (Ribbon weed). …unusual in that they have underwater pollination. Zostera is mainly called as marine eelgrass and pollinated by water method . The liberated pollen germinates and sinks in water. Flowers are small colourless, inconspicuous, odourless and nectarless. These are aquatic plants. Najas is the largest of the 18 hydrophilous angiosperm genera, however, study of pollination biology in the genus is largely ignored. This condition is called homogamy. Transfer of pollen grains shed from anther to stigma of a pistil is called pollination.Flowering plants have evolved an amazing array of adaptations to achieve pollination.Plants can be pollinated by 3 kinds. fig. Anemophily is reported for amphibious and terrestrial species. Vallisneria's male flower or pollen grain are released on the surface of water, which are passively carried away by water currents; some of them eventually reach … This type of pollination mainly observed in Graminae. In some flowers corolla has peculiar forms which act as barrier in self pollination. These ants act as body guards of the plants against any disturbing agent and also helps in pollination. | The flowers which are wind pollinated are called anemophilous. These flowers secrete more nectar than ornithophilous flowers and open at night emit a good fragrance. Ornithophily (Gk. Both the parts of anther are separated apart due to elongation of connective. The usual agents are wind, animals and water. (d) Malacophily : Pollination by slugs and snails is called malacophily. male and female flowers occur on separate plants. | The flowers are well exposed in the air. 1992) , Under such conditions, the cross pollination is the only option. rafflesia. In sea grass like Zostera the pollen grains are filiform and the density of pollen grains is equal to the density of water. Study Packages In this article, we will discuss about the three agents for pollination. ... Epihydrophily and Hypohydrophily. Epihydrophily : Plants which are pollinated outside the water. is the male part of a flower and transferred to the flower’s female part called the stigma It is a mode of pollination performed by bats. Example: Zostera. The influence of floral morphology on fluid flow. About 80% pollination occurs by insects like moths, beetles, butterflies, wasp, etc. The common examples of wind pollinated flowers are -, is true hydrophily which occurs below the surface of, The important pollinating insects are bees, butterflies, moths, wasps, bettles etc. The pollen grains of some plants are not functional. iii) The flowers produce abundant watery nectar. The most common bird pollinators are Sun bird, Humming bird, Crow, Bulbul, Parrot, Mynah, etc. eph/epihydrophily. iv)    Variations caused due to cross pollination may result in production of disease resistant plants. e.g., Vallisneria (Ribbon weed). Pollination by water occurs in Ceratophyllum and Zostera. Some of them possess a long style but short stamens and are known as pin-eyed while others have short style and long stamens. | d. Since the bisexual flowers of Salvia are protandrous, (anthers mature earlier than the gynoecium), cross pollination occurs only when pollen-dusted bee visits older flowers with mature gynoecium. eg.. Other examples of insect plants are Yucca (by Tageticula moth), Orchid Ophrys speculum (by Colpa aurea a hairy wasp), Ficus (by Blastophega), etc. Questions Bank Hibiscus : The stigmas project far above the stamens. The elongated connective has two unequal arms. The male wasps pollinate the flowers mistaking them as female (pseudocopulation). Pollination is defined as the process of transfer of pollen grains from anther to the stigma of the same flower or of different flower of the same species. The stigmas of such flowers are long rough and sticky. The purity of the generation is maintained. It is called self incompatibility. Nectar and odor are absent. An understanding of the process of submarine pollination should provide insight into the evolutionary and reproductive ecology of the marine angiosperms (seagrasses). (b) Ornithophily : When flowers are pollinated by birds, the phenomenon is known as ornithophily. Lalit Sardana Sir In Zostera, the marine angiosperm (Sea Grass), the pollen grains are long ribon-like (upto 2500 mm) and without exine. Ornis = bird, philein = to love) is a mode of pollination performed by birds.