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<title>Double fertilization</title>

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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Double fertilization</span></span>

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<p><b>Double fertilization</b> or <b>double fertilisation</b> (see <a href="American_and_British_English_spelling_differences#-ise,_-ize_(-isation,_-ization)" title="American and British English spelling differences">spelling differences</a>) is a complex <a href="Fertilization" class="mw-redirect" title="Fertilization">fertilization</a> mechanism of <a href="Angiosperms" class="mw-redirect" title="Angiosperms">angiosperms</a>. This process involves the fusion of a female <a href="Gametophyte" title="Gametophyte">gametophyte</a> or <a href="Gametophyte#Heterospory" title="Gametophyte">megagametophyte</a>, also called the <a href="Embryonic_sac" title="Embryonic sac">embryonic sac</a>, with two male <a href="Gamete" title="Gamete">gametes</a> (sperm). It begins when a <a href="Pollen_grain" class="mw-redirect" title="Pollen grain">pollen grain</a> adheres to the stigmatic surface of the <a href="Carpel" class="mw-redirect" title="Carpel">carpel</a>, the female reproductive structure of angiosperm flowers. The pollen grain begins to <a href="Germinate" class="mw-redirect" title="Germinate">germinate</a> (unless a type of <a href="Self-incompatibility" title="Self-incompatibility">self-incompatibility</a> that acts in the stigma occurs in that particular species and is activated), forming a <a href="Pollen_tube" title="Pollen tube">pollen tube</a> that penetrates and extends down through the style toward the <a href="Ovary_(plants)" class="mw-redirect" title="Ovary (plants)">ovary</a> as it follows chemical signals released by the egg. The tip of the pollen tube then enters the ovary by penetrating through the <a href="Ovule" title="Ovule">micropyle</a> opening in the <a href="Ovule" title="Ovule">ovule</a>, and releases two sperm into the embryonic sac (megagametophyte).

</p><p>The mature embryonic sac of an unfertilized ovule is 7-cellular and 8-nucleate. It is arranged in the form of 3+1+3 (from top to bottom) i.e. 3 antipodal cells, 1 central cell (binucleate), 2 synergids & 1 egg cell. One sperm fertilizes the egg cell and the other sperm fuses with the two <b>polar nuclei</b> of the large central cell of the megagametophyte. The <a href="Haploid" class="mw-redirect" title="Haploid">haploid</a> sperm and haploid egg fuse to form a <a href="Diploid" class="mw-redirect" title="Diploid">diploid</a> zygote, the process being called <a href="Syngamy" class="mw-redirect" title="Syngamy">syngamy</a>, while the other sperm and the <a href="Diploid" class="mw-redirect" title="Diploid">diploid</a> central cell fuse to form a <a href="Triploid" class="mw-redirect" title="Triploid">triploid</a> <b>primary endosperm cell</b> (triple fusion). Some plants may form <a href="Polyploid" class="mw-redirect" title="Polyploid">polyploid</a> nuclei. The large cell of the gametophyte will then develop into the <a href="Endosperm" title="Endosperm">endosperm</a>, a nutrient-rich tissue which nourishes the developing embryo. The <a href="Ovary_(botany)" title="Ovary (botany)">ovary</a>, surrounding the ovules, develops into the fruit, which protects the seeds and may function to disperse them.<sup id="cite_ref-Berger2008_1-0" class="reference"><a href="#cite_note-Berger2008-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>

</p><p>The two central cell maternal nuclei (polar nuclei) that contribute to the endosperm, arise by mitosis from the same single <a href="Meiotic" class="mw-redirect" title="Meiotic">meiotic</a> product that gave rise to the egg. The maternal contribution to the genetic constitution of the triploid endosperm is double that of the sperm.

</p><p>In a study conducted in 2008 of the plant <i><a href="Arabidopsis_thaliana" title="Arabidopsis thaliana">Arabidopsis thaliana</a></i>, the migration of male nuclei inside the female gamete, in fusion with the female nuclei, has been documented for the first time using <a href="In_vivo" title="In vivo">in vivo</a> imaging. Some of the genes involved in the migration and fusion process have also been determined.<sup id="cite_ref-Hamamura2008_2-0" class="reference"><a href="#cite_note-Hamamura2008-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup>

</p><p>Evidence of double fertilization in <a href="Gnetales" class="mw-redirect" title="Gnetales">Gnetales</a>, which are non-flowering seed plants, has been reported.<sup id="cite_ref-Raghavan2003_3-0" class="reference"><a href="#cite_note-Raghavan2003-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading2"><h2 id="Brief_history">Brief history</h2></div>

<p>Double fertilization was discovered more than a century ago by <a href="Sergei_Navashin" title="Sergei Navashin">Sergei Nawaschin</a> in <a href="Kyiv" title="Kyiv">Kyiv</a>,<sup id="cite_ref-pmid18822860_4-0" class="reference"><a href="#cite_note-pmid18822860-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> and <a href="L%C3%A9on_Guignard" title="Léon Guignard">Léon Guignard</a> in <a href="France" title="France">France</a>. Each made the discovery independently of the other.<sup id="cite_ref-Jensen1998_5-0" class="reference"><a href="#cite_note-Jensen1998-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> <i><a href="Lilium_martagon" title="Lilium martagon">Lilium martagon</a></i> and <i><a href="Fritillaria" title="Fritillaria">Fritillaria</a> <a href="Fritillaria_tenella" class="mw-redirect" title="Fritillaria tenella">tenella</a></i> were used in the first observations of double fertilization, which were made using the classical <a href="Light_microscope" class="mw-redirect" title="Light microscope">light microscope</a>. Due to the limitations of the light microscope, there were many unanswered questions regarding the process of double fertilization. However, with the development of the <a href="Electron_microscope" title="Electron microscope">electron microscope</a>, many of the questions were answered. Most notably, the observations made by the group of W. Jensen showed that the male gametes did not have any <a href="Cell_wall" title="Cell wall">cell walls</a> and that the <a href="Plasma_membrane" class="mw-redirect" title="Plasma membrane">plasma membrane</a> of the gametes is close to the plasma membrane of the cell that surrounds them inside the pollen grain.<sup id="cite_ref-Dumas2008_6-0" class="reference"><a href="#cite_note-Dumas2008-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading2"><h2 id="Double_fertilization_in_gymnosperms">Double fertilization in gymnosperms</h2></div>

<p>A far more rudimentary form of double fertilization occurs in the sexual reproduction of an order of gymnosperms commonly known as Gnetales.<sup id="cite_ref-Raghavan2003_3-1" class="reference"><a href="#cite_note-Raghavan2003-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> Specifically, this event has been documented in both <a href="Ephedra_(plant)" title="Ephedra (plant)"><i>Ephedra</i></a> and <i><a href="Gnetum" title="Gnetum">Gnetum</a></i>, a subset of <a href="Gnetophyta" title="Gnetophyta">gnetophytes</a>.<sup id="cite_ref-:1_7-0" class="reference"><a href="#cite_note-:1-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> In <i><a href="Ephedra_nevadensis" title="Ephedra nevadensis">Ephedra nevadensis</a></i>, a single binucleate sperm cell is deposited into the egg cell. Following the initial fertilization event, the second sperm nucleus is diverted to fertilize an additional egg nucleus found in the egg cytoplasm. In most other seed plants, this second 'ventral canal nucleus' is normally found to be functionally useless.<sup id="cite_ref-:4_8-0" class="reference"><a href="#cite_note-:4-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> In <i><a href="Gnetum_gnemon" title="Gnetum gnemon">Gnetum gnemon</a></i>, numerous free egg nuclei exist in female cytoplasm inside the female <a href="Gametophyte" title="Gametophyte">gametophyte</a>. Succeeding the penetration of the mature female gametophyte by the <a href="Pollen_tube" title="Pollen tube">pollen tube</a>, female cytoplasm and free nuclei move to surround the pollen tube. Released from the binucleate sperm cell are two sperm nuclei which then fuse with free egg nuclei to produce two viable zygotes, a homologous characteristic between families <i>Ephedra</i> and <i>Gnetum</i>.<sup id="cite_ref-:5_9-0" class="reference"><a href="#cite_note-:5-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> In both families, the second fertilization event produces an additional diploid <a href="Embryo" title="Embryo">embryo</a>. This supernumerary embryo is later aborted, leading to the synthesis of only one mature embryo.<sup id="cite_ref-:2_10-0" class="reference"><a href="#cite_note-:2-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> The additional fertilization product in <i>Ephedra</i> does not nourish the primary embryo, as the female gametophyte is responsible for nutrient provision.<sup id="cite_ref-:5_9-1" class="reference"><a href="#cite_note-:5-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> The more primitive process of double fertilization in <a href="Gymnosperm" title="Gymnosperm">gymnosperms</a> results in two diploid nuclei enclosed in the same egg cell. This differs from the <a href="Flowering_plant" title="Flowering plant">angiosperm</a> condition, which results in the separation of the egg cell and <a href="Endosperm" title="Endosperm">endosperm</a>.<sup id="cite_ref-:6_11-0" class="reference"><a href="#cite_note-:6-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> Comparative molecular research on the genome of <i>G. gnemon</i> has revealed that gnetophytes are more closely related to <a href="Pinophyta" class="mw-redirect" title="Pinophyta">conifers</a> than they are to angiosperms.<sup id="cite_ref-:8_12-0" class="reference"><a href="#cite_note-:8-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-:32_13-0" class="reference"><a href="#cite_note-:32-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> The rejection of the anthophyte hypothesis, which identifies gnetales and angiosperms are sister taxa, leads to speculation that the process of double fertilization is a product of <a href="Convergent_evolution" title="Convergent evolution">convergent evolution</a> and arose independently among gnetophytes and angiosperms.<sup id="cite_ref-:7_15-0" class="reference"><a href="#cite_note-:7-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading2"><h2 id="In_vitro_double_fertilization">In vitro double fertilization</h2></div>

<p>In vitro double fertilization is often used to study the molecular interactions as well as other aspects of gamete fusion in flowering plants. One of the major obstacles in developing an in vitro double fertilization between male and female gametes is the confinement of the sperm in the pollen tube and the egg in the embryonic sac. A controlled fusion of the egg and sperm has already been achieved with <a href="Poppy" title="Poppy">poppy plants</a>.<sup id="cite_ref-Zenkteler1990_16-0" class="reference"><a href="#cite_note-Zenkteler1990-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> <a href="Germination#Pollen_germination" title="Germination">Pollen germination</a>, pollen tube entry, and double fertilization processes have all been observed to proceed normally. In fact, this technique has already been used to obtain seeds in various flowering plants and was named “test-tube fertilization”.<sup id="cite_ref-Raghavan2005_17-0" class="reference"><a href="#cite_note-Raghavan2005-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading2"><h2 id="Related_structures_and_functions">Related structures and functions</h2></div>

<div class="mw-heading mw-heading3"><h3 id="Megagametophyte">Megagametophyte</h3></div>

<p>The female gametophyte, the megagametophyte, that participates in double fertilization in <a href="Angiosperm" class="mw-redirect" title="Angiosperm">angiosperms</a> which is haploid is called the embryonic sac. This develops within an <a href="Ovule" title="Ovule">ovule</a>, enclosed by the ovary at the base of a <a href="Carpel" class="mw-redirect" title="Carpel">carpel</a>. Surrounding the megagametophyte are (one or) two <a href="Integument" title="Integument">integuments</a>, which form an opening called the <a href="Micropyle_(botany)" class="mw-redirect" title="Micropyle (botany)">micropyle</a>. The megagametophyte, which is usually <a href="Haploid" class="mw-redirect" title="Haploid">haploid</a>, originates from the (usually <a href="Diploid" class="mw-redirect" title="Diploid">diploid</a>) <a href="Megaspore" title="Megaspore">megaspore</a> mother cell, also called the <a href="Megasporocyte" class="mw-redirect" title="Megasporocyte">megasporocyte</a>. The next sequence of events varies, depending on the particular species, but in most species, the following events occur. The megasporocyte undergoes meiosis, producing four haploid megaspores. Only one of the four resulting megaspores survives. This megaspore undergoes three rounds of mitosis, resulting in seven cells with eight haploid nuclei (the central cell has two nuclei, called the polar nuclei). The lower end of the embryonic sac consists of the haploid egg cell positioned in the middle of two other haploid cells, called <a href="Synergid" class="mw-redirect" title="Synergid">synergids</a>. The synergids function in the attraction and guidance of the pollen tube to the megagametophyte through the micropyle. At the upper end of the megagametophyte are three antipodal cells.

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<div class="mw-heading mw-heading3"><h3 id="Microgametophyte">Microgametophyte</h3></div>

<p>The male gametophytes, or microgametophytes, that participate in double fertilization are contained within <a href="Pollen" title="Pollen">pollen</a> grains. They develop within the microsporangia, or <a href="Pollen#The_structure_and_formation_of_pollen" title="Pollen">pollen sacs</a>, of the anthers on the stamens. Each microsporangium contains diploid <a href="Microspore" title="Microspore">microspore</a> mother cells, or microsporocytes. Each microsporocyte undergoes meiosis, forming four haploid microspores, each of which can eventually develop into a pollen grain. A microspore undergoes <a href="Mitosis" title="Mitosis">mitosis</a> and <a href="Cytokinesis" title="Cytokinesis">cytokinesis</a> in order to produce two separate cells, the generative cell and the tube cell. These two cells in addition to the spore wall make up an immature pollen grain. As the male gametophyte matures, the generative cell passes into the tube cell, and the generative cell undergoes mitosis, producing two sperm cells. Once the pollen grain has matured, the <a href="Anthers" class="mw-redirect" title="Anthers">anthers</a> break open, releasing the pollen. The pollen is carried to the <a href="Pistil" class="mw-redirect" title="Pistil">pistil</a> of another flower, by wind or animal pollinators, and deposited on the stigma. As the pollen grain germinates, the tube cell produces the pollen tube, which elongates and extends down the long style of the carpel and into the ovary, where its sperm cells are released in the megagametophyte. Double fertilization proceeds from here.<sup id="cite_ref-Campbell2005_18-0" class="reference"><a href="#cite_note-Campbell2005-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup>

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<ul><li><a href="Fertilisation" title="Fertilisation">Fertilisation</a></li>

<li><a href="Gamete" title="Gamete">Gamete</a></li>

<li><a href="Megaspore" title="Megaspore">Megaspore</a></li>

<li><a href="Oosphere" class="mw-redirect" title="Oosphere">Oosphere</a></li>

<li><a href="Ovule" title="Ovule">Ovule</a></li>

<li><a href="Pollen" title="Pollen">Pollen</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><cite id="CITEREFBerger,_F.2008" class="citation journal cs1">Berger, F. (January 2008). "Double-fertilization, from myths to reality". <i>Sexual Plant Reproduction</i>. <b>21</b> (1): <span class="nowrap">3–</span>5. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2Fs00497-007-0066-4">10.1007/s00497-007-0066-4</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:8928640">8928640</a>.</cite></span>

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<li id="cite_note-Hamamura2008-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-Hamamura2008_2-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFBerger,_F.Hamamura,_Y._&_Ingouff,_M._&_Higashiyama,_T.2008" class="citation journal cs1">Berger, F.; Hamamura, Y. & Ingouff, M. & Higashiyama, T. (August 2008). "Double fertilization – Caught In The Act". <i><a href="Trends_in_Plant_Science" title="Trends in Plant Science">Trends in Plant Science</a></i>. <b>13</b> (8): <span class="nowrap">437–</span>443. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2Fj.tplants.2008.05.011">10.1016/j.tplants.2008.05.011</a>. <a href="PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/18650119">18650119</a>.</cite><span class="cs1-maint citation-comment"><code class="cs1-code">{{cite journal}}</code>: CS1 maint: multiple names: authors list (link)</span></span>

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<cite id="CITEREFV._Raghavan2003" class="citation journal cs1">V. Raghavan (September 2003). "Some reflections on double fertilization, from its discovery to the present". <i><a href="New_Phytologist" title="New Phytologist">New Phytologist</a></i>. <b>159</b> (3): <span class="nowrap">565–</span>583. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1046%2Fj.1469-8137.2003.00846.x">10.1046/j.1469-8137.2003.00846.x</a>. <a href="PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/33873607">33873607</a>.</cite></span>

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<li id="cite_note-pmid18822860-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-pmid18822860_4-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFKordium_EL2008" class="citation journal cs1 cs1-prop-foreign-lang-source">Kordium EL (2008). "[Double fertilization in flowering plants: 1898-20&&&--". <i>Tsitol. Genet.</i> (in Russian). <b>42</b> (3): <span class="nowrap">12–</span>26. <a href="PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/18822860">18822860</a>.</cite></span>

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<li id="cite_note-Jensen1998-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-Jensen1998_5-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFJensen,_W._A.1998" class="citation journal cs1">Jensen, W. A. (February 1998). "Double Fertilization: A Personal View". <i>Sexual Plant Reproduction</i>. <b>11</b> (1): <span class="nowrap">1–</span>5. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2Fs004970050113">10.1007/s004970050113</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:33416360">33416360</a>.</cite></span>

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<li id="cite_note-Dumas2008-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-Dumas2008_6-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFDumas,_C.Rogowsky,_P.2008" class="citation journal cs1">Dumas, C. & Rogowsky, P. (August 2008). <span class="id-lock-subscription" title="Paid subscription required"><a rel="nofollow" class="external text" href="https://comptes-rendus.academie-sciences.fr/biologies/articles/10.1016/j.crvi.2008.07.013/">"Fertilization and Early Seed Formation"</a></span>. <i><a href="Comptes_Rendus_Biologies" class="mw-redirect" title="Comptes Rendus Biologies">Comptes Rendus Biologies</a></i>. <b>331</b> (10): <span class="nowrap">715–</span>725. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2Fj.crvi.2008.07.013">10.1016/j.crvi.2008.07.013</a>. <a href="PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/18926485">18926485</a>.</cite></span>

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<li id="cite_note-:1-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-:1_7-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFCarmichaelFriedman1995" class="citation journal cs1">Carmichael, J. S.; Friedman, W. E. (1995-12-01). <a rel="nofollow" class="external text" href="http://www.plantcell.org/content/7/12/1975">"Double Fertilization in Gnetum gnemon: The Relationship between the Cell Cycle and Sexual Reproduction"</a>. <i>The Plant Cell</i>. <b>7</b> (12): <span class="nowrap">1975–</span>1988. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1105%2Ftpc.7.12.1975">10.1105/tpc.7.12.1975</a>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1040-4651">1040-4651</a>. <a href="PMC_(identifier)" class="mw-redirect" title="PMC (identifier)">PMC</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC161055">161055</a></span>. <a href="PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/12242365">12242365</a>.</cite></span>

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<li id="cite_note-:4-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-:4_8-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFFriedman1990" class="citation journal cs1">Friedman, William E. (1990). "Sexual Reproduction in Ephedra nevadensis (Ephedraceae): Further Evidence of Double Fertilization in a Nonflowering Seed Plant". <i>American Journal of Botany</i>. <b>77</b> (12): <span class="nowrap">1582–</span>1598. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1002%2Fj.1537-2197.1990.tb11399.x">10.1002/j.1537-2197.1990.tb11399.x</a>. <a href="JSTOR_(identifier)" class="mw-redirect" title="JSTOR (identifier)">JSTOR</a> <a rel="nofollow" class="external text" href="https://www.jstor.org/stable/2444491">2444491</a>.</cite></span>

</li>

<li id="cite_note-:5-9"><span class="mw-cite-backlink">^ <a href="#cite_ref-:5_9-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-:5_9-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><cite id="CITEREFCarmichaelFriedman1996" class="citation journal cs1">Carmichael, Jeffrey S.; Friedman, William E. (1996). "Double Fertilization in Gnetum gnemon (Gnetaceae): Its Bearing on the Evolution of Sexual Reproduction within the Gnetales and the Anthophyte Clade". <i>American Journal of Botany</i>. <b>83</b> (6): <span class="nowrap">767–</span>780. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1002%2Fj.1537-2197.1996.tb12766.x">10.1002/j.1537-2197.1996.tb12766.x</a>. <a href="JSTOR_(identifier)" class="mw-redirect" title="JSTOR (identifier)">JSTOR</a> <a rel="nofollow" class="external text" href="https://www.jstor.org/stable/2445854">2445854</a>.</cite></span>

</li>

<li id="cite_note-:2-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-:2_10-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFFriedman1995" class="citation journal cs1">Friedman, W. E. (1995-04-25). <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC42072">"Organismal duplication, inclusive fitness theory, and altruism: understanding the evolution of endosperm and the angiosperm reproductive syndrome"</a>. <i>Proceedings of the National Academy of Sciences</i>. <b>92</b> (9): <span class="nowrap">3913–</span>3917. <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1995PNAS...92.3913F">1995PNAS...92.3913F</a>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1073%2Fpnas.92.9.3913">10.1073/pnas.92.9.3913</a></span>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0027-8424">0027-8424</a>. <a href="PMC_(identifier)" class="mw-redirect" title="PMC (identifier)">PMC</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC42072">42072</a></span>. <a href="PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/11607532">11607532</a>.</cite></span>

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<li id="cite_note-:6-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-:6_11-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFFriedman1994" class="citation journal cs1">Friedman, William E. (1994). "The Evolution of Embryogeny in Seed Plants and the Developmental Origin and Early History of Endosperm". <i>American Journal of Botany</i>. <b>81</b> (11): <span class="nowrap">1468–</span>1486. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1002%2Fj.1537-2197.1994.tb15633.x">10.1002/j.1537-2197.1994.tb15633.x</a>. <a href="JSTOR_(identifier)" class="mw-redirect" title="JSTOR (identifier)">JSTOR</a> <a rel="nofollow" class="external text" href="https://www.jstor.org/stable/2445320">2445320</a>.</cite></span>

</li>

<li id="cite_note-:8-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-:8_12-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFBoweCoatdePamphilis2000" class="citation journal cs1">Bowe, L. Michelle; Coat, Gwénaële; dePamphilis, Claude W. (2000-04-11). <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC18159">"Phylogeny of seed plants based on all three genomic compartments: Extant gymnosperms are monophyletic and Gnetales' closest relatives are conifers"</a>. <i>Proceedings of the National Academy of Sciences</i>. <b>97</b> (8): <span class="nowrap">4092–</span>4097. <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2000PNAS...97.4092B">2000PNAS...97.4092B</a>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1073%2Fpnas.97.8.4092">10.1073/pnas.97.8.4092</a></span>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0027-8424">0027-8424</a>. <a href="PMC_(identifier)" class="mw-redirect" title="PMC (identifier)">PMC</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC18159">18159</a></span>. <a href="PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/10760278">10760278</a>.</cite></span>

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<li id="cite_note-:32-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-:32_13-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFWinterBeckerMünsterKim1999" class="citation journal cs1">Winter, Kai-Uwe; Becker, Annette; Münster, Thomas; Kim, Jan T.; Saedler, Heinz; Theissen, Günter (1999-06-22). <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC22087">"MADS-box genes reveal that gnetophytes are more closely related to conifers than to flowering plants"</a>. <i>Proceedings of the National Academy of Sciences</i>. <b>96</b> (13): <span class="nowrap">7342–</span>7347. <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1999PNAS...96.7342W">1999PNAS...96.7342W</a>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1073%2Fpnas.96.13.7342">10.1073/pnas.96.13.7342</a></span>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0027-8424">0027-8424</a>. <a href="PMC_(identifier)" class="mw-redirect" title="PMC (identifier)">PMC</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC22087">22087</a></span>. <a href="PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/10377416">10377416</a>.</cite></span>

</li>

<li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><cite id="CITEREFMagallonSanderson2002" class="citation journal cs1">Magallon, S.; Sanderson, M. J. (2002-12-01). <a rel="nofollow" class="external text" href="https://doi.org/10.3732%2Fajb.89.12.1991">"Relationships among seed plants inferred from highly conserved genes: sorting conflicting phylogenetic signals among ancient lineages"</a>. <i>American Journal of Botany</i>. <b>89</b> (12): <span class="nowrap">1991–</span>2006. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.3732%2Fajb.89.12.1991">10.3732/ajb.89.12.1991</a></span>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1537-2197">1537-2197</a>. <a href="PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/21665628">21665628</a>.</cite></span>

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<li id="cite_note-:7-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-:7_15-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFChawParkinsonChengVincent2000" class="citation journal cs1">Chaw, Shu-Miaw; Parkinson, Christopher L.; Cheng, Yuchang; Vincent, Thomas M.; Palmer, Jeffrey D. (2000-04-11). <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC18157">"Seed plant phylogeny inferred from all three plant genomes: Monophyly of extant gymnosperms and origin of Gnetales from conifers"</a>. <i>Proceedings of the National Academy of Sciences</i>. <b>97</b> (8): <span class="nowrap">4086–</span>4091. <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2000PNAS...97.4086C">2000PNAS...97.4086C</a>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1073%2Fpnas.97.8.4086">10.1073/pnas.97.8.4086</a></span>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0027-8424">0027-8424</a>. <a href="PMC_(identifier)" class="mw-redirect" title="PMC (identifier)">PMC</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC18157">18157</a></span>. <a href="PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/10760277">10760277</a>.</cite></span>

</li>

<li id="cite_note-Zenkteler1990-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-Zenkteler1990_16-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFZenkteler,_M.1990" class="citation journal cs1">Zenkteler, M. (1990). "In vitro fertilization and wide hybridization in higher plants". <i>Crit Rev Plant Sci</i>. <b>9</b> (3): <span class="nowrap">267–</span>279. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1080%2F07352689009382290">10.1080/07352689009382290</a>.</cite></span>

</li>

<cite id="CITEREFRaghavan,_V.2005" class="citation book cs1">Raghavan, V. (2005). <i>Double fertilization: embryo and endosperm development in flowering plants</i> (illustrated ed.). Birkhäuser. pp. <span class="nowrap">17–</span>19. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-3-540-27791-0</bdi>.</cite></span>

</li>

<li id="cite_note-Campbell2005-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-Campbell2005_18-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFCampbell_N.A.Reece_J.B.2005" class="citation book cs1">Campbell N.A.; Reece J.B. (2005). <i>Biology</i> (7 ed.). San Francisco, CA: Pearson Education, Inc. pp. <span class="nowrap">774–</span>777. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-8053-7171-0</bdi>.</cite></span>

</li>

</ol></div>

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</style><div id="Botany855" style="font-size:114%;margin:0 4em"><a href="Botany" title="Botany">Botany</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="2" style="background: #C3EEC3;"><div>

<ul><li><a href="History_of_botany" title="History of botany">History</a></li>

<li><a href="Outline_of_botany" title="Outline of botany">Outline</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="background: #C3EEC3;;width:1%"><a href="Branches_of_botany" title="Branches of botany">Subdisciplines</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Archaeobotany" class="mw-redirect" title="Archaeobotany">Archaeobotany</a></li>

<li><a href="Astrobotany" title="Astrobotany">Astrobotany</a></li>

<li><a href="Bryology" title="Bryology">Bryology</a></li>

<li><a href="Dendrology" title="Dendrology">Dendrology</a></li>

<li><a href="Ethnobotany" title="Ethnobotany">Ethnobotany</a></li>

<li><a href="Paleobotany" title="Paleobotany">Paleobotany</a></li>

<li><a href="Phycology" title="Phycology">Phycology</a></li>

<li><a href="Phytochemistry" title="Phytochemistry">Phytochemistry</a></li>

<li><a href="Phytogeography" title="Phytogeography">Phytogeography</a>

<ul><li><a href="Geobotanical_prospecting" title="Geobotanical prospecting">Geobotany</a></li></ul></li>

<li><a href="Plant_anatomy" title="Plant anatomy">Plant anatomy</a></li>

<li><a href="Plant_ecology" title="Plant ecology">Plant ecology</a></li>

<li><a href="Plant_intelligence" title="Plant intelligence">Plant intelligence</a></li>

<li><a href="Plant_pathology" title="Plant pathology">Plant pathology</a></li>

<li><a href="Plant_physiology" title="Plant physiology">Plant physiology</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="background: #C3EEC3;;width:1%"><a href="Plant" title="Plant">Plant</a> groups</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Algae" title="Algae">Algae</a></li>

<li><a href="Archaeplastida" title="Archaeplastida">Archaeplastida</a></li>

<li><a href="Bryophyte" title="Bryophyte">Bryophyte</a></li>

<li><a href="Non-vascular_plant" title="Non-vascular plant">Non-vascular plants</a></li>

<li><a href="Vascular_plant" title="Vascular plant">Vascular plants</a></li>

<li><a href="Lycophyte" title="Lycophyte">Lycophyte</a></li>

<li><a href="Spermatophyte" class="mw-redirect" title="Spermatophyte">Spermatophytes</a></li>

<li><a href="Gymnosperm" title="Gymnosperm">Gymnosperm</a></li>

<li><a href="Flowering_plant" title="Flowering plant">Angiosperm</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="background: #C3EEC3;;width:1%"><a href="Plant_anatomy" title="Plant anatomy">Plant anatomy</a> <div class="hlist"><ul><li><a href="Plant_morphology" title="Plant morphology">Plant morphology</a><br><span class="nobold">(<a href="Glossary_of_plant_morphology" title="Glossary of plant morphology">glossary</a>)</span></li></ul></div></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="background: #D4EED4;;width:1%"><a href="Plant_cell" title="Plant cell">Plant cells</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Phragmoplast" title="Phragmoplast">Phragmoplast</a></li>

<li><a href="Plastid" title="Plastid">Plastid</a></li>

<li><a href="Plasmodesma" title="Plasmodesma">Plasmodesma</a></li>

<li><a href="Vacuole" title="Vacuole">Vacuole</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="background: #D4EED4;;width:1%"><a href="Tissue_(biology)" title="Tissue (biology)">Tissues</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Ground_tissue" title="Ground tissue">Ground tissue</a>

<ul><li><a href="Leaf#Mesophyll" title="Leaf">Mesophyll</a></li></ul></li>

<li><a href="Meristem" title="Meristem">Meristem</a></li>

<li><a href="Storage_organ" title="Storage organ">Storage organs</a></li>

<li><a href="Vascular_tissue" title="Vascular tissue">Vascular tissue</a>

<ul><li><a href="Vascular_bundle" title="Vascular bundle">Vascular bundle</a></li></ul></li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="background: #D4EED4;;width:1%">Vegetative</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Rhizoid" title="Rhizoid">Rhizoid</a></li>

<li><a href="Rhizome" title="Rhizome">Rhizome</a></li>

<li><a href="Shoot_(botany)" title="Shoot (botany)">Shoot</a>

<ul><li><a href="Cataphyll" title="Cataphyll">Cataphyll</a></li>

<li><a href="Petiole_(botany)" title="Petiole (botany)">Petiole</a></li></ul></li>

<li><a href="Sessility_(botany)" title="Sessility (botany)">Sessility</a></li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="background: #D4EED4;;width:1%"><a href="Plant_reproductive_morphology" title="Plant reproductive morphology">Reproductive</a><br>(incl. Flower)</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Archegonium" title="Archegonium">Archegonium</a></li>

<li><a href="Antheridium" title="Antheridium">Antheridium</a></li>

<li><a href="Stamen" title="Stamen">Androecium</a>

<ul><li><a href="Pollen" title="Pollen">Pollen</a></li>

<li><a href="Stamen" title="Stamen">Stamen</a>

<ul><li><a href="Anther" class="mw-redirect" title="Anther">Anther</a></li>

<li><a href="Stamen#Morphology_and_terminology" title="Stamen">Filament</a></li></ul></li>

<li><a href="Staminode" title="Staminode">Staminode</a></li>

<li><a href="Tapetum_(botany)" title="Tapetum (botany)">Tapetum</a></li></ul></li>

<li><a href="Flower" title="Flower">Flower</a>

<ul><li><a href="Aestivation_(botany)" title="Aestivation (botany)">Aestivation</a></li>

<li><a href="ABC_model_of_flower_development" title="ABC model of flower development">Flower development</a></li>

<li><a href="Floral_diagram" title="Floral diagram">Floral diagram</a></li>

<li><a href="Floral_formula" title="Floral formula">Floral formula</a></li>

<li><a href="Floral_symmetry" title="Floral symmetry">Floral symmetry</a></li>

<li><a href="Whorl_(botany)" title="Whorl (botany)">Whorl</a></li></ul></li>

<li><a href="Fruit" title="Fruit">Fruit</a>

<ul><li><a href="Fruit_anatomy" class="mw-redirect" title="Fruit anatomy">Anatomy</a></li>

<li><a href="Berry_(botany)" title="Berry (botany)">Berry</a></li>

<li><a href="Capsule_(fruit)" title="Capsule (fruit)">Capsule</a></li>

<li><a href="Pyrena" title="Pyrena">Pyrena</a></li>

<ul><li><a href="Seed_dispersal" title="Seed dispersal">Dispersal</a></li>

<li><a href="Endosperm" title="Endosperm">Endosperm</a></li></ul></li></ul></li>

<li><a href="Gametophyte" title="Gametophyte">Gametophyte</a></li>

<li><a href="Column_(botany)" title="Column (botany)">Gynandrium</a></li>

<li><a href="Gynoecium" title="Gynoecium">Gynoecium</a>

<ul><li><a href="Carpel" class="mw-redirect" title="Carpel">Carpel</a>

<ul><li><a href="Ovary_(botany)" title="Ovary (botany)">Ovary</a>

<ul><li><a href="Locule" title="Locule">Locule</a></li>

<li><a href="Ovule" title="Ovule">Ovule</a></li></ul></li>

<li><a href="Stigma_(botany)" title="Stigma (botany)">Stigma</a></li>

<li><a href="Style_(botany)" title="Style (botany)">Style</a></li></ul></li></ul></li>

<li><a href="Hypanthium" title="Hypanthium">Hypanthium (Floral cup)</a></li>

<li><a href="Inflorescence" title="Inflorescence">Inflorescence</a>

<ul><li><a href="Bract" title="Bract">Bract</a></li>

<li><a href="Pedicel_(botany)" title="Pedicel (botany)">Pedicellate</a></li>

<li><a href="Raceme" title="Raceme">Raceme</a></li>

<li><a href="Umbel" title="Umbel">Umbel</a></li></ul></li>

<li><a href="Perianth" title="Perianth">Perianth</a>

<ul><li><a href="Tepal" title="Tepal">Tepal</a></li>

<li><a href="Petal" title="Petal">Petal</a></li>

<li><a href="Sepal" title="Sepal">Sepal</a></li></ul></li>

<li><a href="Embryo#Plant_embryos" title="Embryo">Plant embryo</a></li>

<li><a href="Receptacle_(botany)" title="Receptacle (botany)">Receptacle</a></li>

<li><a href="Sporophyll" title="Sporophyll">Sporophyll</a></li>

<li><a href="Sporophyte" title="Sporophyte">Sporophyte</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="background: #D4EED4;;width:1%">Surface structures</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Plant_cuticle" title="Plant cuticle">Cuticle</a></li>

<li><a href="Epicuticular_wax" title="Epicuticular wax">Epicuticular wax</a></li>

<li><a href="Epidermis_(botany)" title="Epidermis (botany)">Epidermis</a></li>

<li><a href="Nectar" title="Nectar">Nectar</a></li>

<li><a href="Stoma" title="Stoma">Stoma</a></li>

<li><a href="Thorns%2C_spines%2C_and_prickles" title="Thorns, spines, and prickles">Thorns, spines, and prickles</a></li>

<li><a href="Trichome" title="Trichome">Trichome</a></li></ul>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="background: #C3EEC3;;width:1%"><a href="Plant_physiology" title="Plant physiology">Plant physiology</a><br>Materials</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Aleurone" title="Aleurone">Aleurone</a></li>

<li><a href="Apical_dominance" title="Apical dominance">Apical dominance</a></li>

<li><a href="Cellulose" title="Cellulose">Cellulose</a></li>

<li><a href="Plant_nutrition" title="Plant nutrition">Nutrition</a></li>

<li><a href="Photosynthesis" title="Photosynthesis">Photosynthesis</a>

<ul><li><a href="Chlorophyll" title="Chlorophyll">Chlorophyll</a></li></ul></li>

<li><a href="Phytomelanin" title="Phytomelanin">Phytomelanin</a></li>

<li><a href="Plant_hormone" title="Plant hormone">Plant hormones</a></li>

<li><a href="Respiratory_system#Plants" title="Respiratory system">Respiration</a>

<ul><li><a href="Gas_exchange#Plants" title="Gas exchange">Gas Exchange</a></li>

<li><a href="Cellular_respiration" title="Cellular respiration">Cellular respiration</a></li></ul></li>

<li><a href="Starch" title="Starch">Starch</a></li>

<li><a href="Sugar" title="Sugar">Sugar</a></li>

<li><a href="Transpiration" title="Transpiration">Transpiration</a></li>

<li><a href="Turgor_pressure" title="Turgor pressure">Turgor pressure</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="background: #C3EEC3;;width:1%">Plant growth<br>and habit</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Habit_(biology)#Structure" title="Habit (biology)">Habit</a>

<ul><li><a href="Cushion_plant" title="Cushion plant">Cushion plants</a></li>

<li><a href="Rosette_(botany)" title="Rosette (botany)">Rosettes</a></li>

<li><a href="Shrub" title="Shrub">Shrubs</a>

<ul><li><a href="Prostrate_shrub" title="Prostrate shrub">Prostrate shrubs</a></li>

<li><a href="Subshrub" title="Subshrub">Subshrubs</a></li></ul></li>

<li><a href="Succulent_plant" title="Succulent plant">Succulent plants</a></li>

<li><a href="Tree" title="Tree">Trees</a></li>

<li><a href="Vine" title="Vine">Vines</a>

<ul><li><a href="Liana" title="Liana">Lianas</a></li></ul></li></ul></li>

<li><a href="Herbaceous_plant" title="Herbaceous plant">Herbaceous plants</a></li>

<li><a href="Secondary_growth" title="Secondary growth">Secondary growth</a></li>

<li><a href="Woody_plant" title="Woody plant">Woody plants</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="background: #C3EEC3;;width:1%"><a href="Plant_reproduction" title="Plant reproduction">Reproduction</a> <div class="hlist"><ul><li><a href="Plant_evolution" title="Plant evolution">Evolution</a></li><li><a href="Plant_ecology" title="Plant ecology">Ecology</a></li></ul></div></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Alternation_of_generations" title="Alternation of generations">Alternation of generations</a></li>

<li><a href="Plant_evolutionary_developmental_biology" title="Plant evolutionary developmental biology">Evolutionary development</a></li>

<li><a href="Evolutionary_history_of_plants" title="Evolutionary history of plants">Evolutionary history</a>

<ul><li><a href="Timeline_of_plant_evolution" title="Timeline of plant evolution">timeline</a></li></ul></li>

<li><a href="Flora" title="Flora">Flora</a></li>

<li><a href="Germination" title="Germination">Germination</a></li>

<li><a href="Pollination" title="Pollination">Pollination</a>

<ul><li><a href="Artificial_pollination" class="mw-redirect" title="Artificial pollination">Artificial</a></li>

<li><a href="Pollinator" title="Pollinator">Pollinators</a></li>

<li><a href="Pollen_tube" title="Pollen tube">Pollen tube</a></li>

<li><a href="Sporangium" title="Sporangium">Sporangium</a>

<ul><li><a href="Microsporangia" class="mw-redirect" title="Microsporangia">Microsporangia</a>

<ul><li><a href="Microspore" title="Microspore">Microspore</a></li></ul></li>

<li><a href="Sporangium" title="Sporangium">Megasporangium</a>

<ul><li><a href="Megaspore" title="Megaspore">Megaspore</a></li></ul></li>

<li><a href="Spore" title="Spore">Spore</a></li></ul></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="background: #C3EEC3;;width:1%"><a href="Plant_taxonomy" title="Plant taxonomy">Plant taxonomy</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Taxonomy_(biology)" title="Taxonomy (biology)">Biological classification</a></li>

<li><a href="Botanical_nomenclature" title="Botanical nomenclature">Botanical nomenclature</a>

<ul><li><a href="Botanical_name" title="Botanical name">Botanical name</a></li>

<li><a href="Correct_name" title="Correct name">Correct name</a></li>

<li><a href="Author_citation_(botany)" title="Author citation (botany)">Author citation</a></li>

<li><a href="International_Code_of_Nomenclature_for_algae%2C_fungi%2C_and_plants" title="International Code of Nomenclature for algae, fungi, and plants">International Code of Nomenclature (ICN)</a></li>

<li><a href="International_Code_of_Nomenclature_for_Cultivated_Plants" title="International Code of Nomenclature for Cultivated Plants">ICN for Cultivated Plants (ICNCP)</a></li></ul></li>

<li><a href="Cultivated_plant_taxonomy" title="Cultivated plant taxonomy">Cultivated plant taxonomy</a>

<ul><li><a href="Citrus_taxonomy" title="Citrus taxonomy">Citrus taxonomy</a></li>

<li><a href="Cultigen" title="Cultigen">Cultigen</a>

<ul><li><a href="Cultivar" title="Cultivar">Cultivar</a></li>

<li><a href="Cultivar_group" title="Cultivar group">Group</a></li>

<li><a href="History_of_plant_systematics" title="History of plant systematics">History of plant systematics</a></li>

<li><a href="Herbarium" title="Herbarium">Herbarium</a></li>

<li><a href="International_Association_for_Plant_Taxonomy" title="International Association for Plant Taxonomy">International Association for Plant Taxonomy</a> (IAPT)</li>

<li><a href="List_of_systems_of_plant_taxonomy" title="List of systems of plant taxonomy">Plant taxonomy systems</a></li>

<li><a href="Taxonomic_rank" title="Taxonomic rank">Taxonomic rank</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="background: #C3EEC3;;width:1%">Practice</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Agronomy" title="Agronomy">Agronomy</a></li>

<li><a href="Floriculture" title="Floriculture">Floriculture</a></li>

<li><a href="Forestry" title="Forestry">Forestry</a></li>

<li><a href="Horticulture" title="Horticulture">Horticulture</a></li>

<li><a href="Phytochemical" title="Phytochemical">Phytochemical</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="background: #C3EEC3;;width:1%"><div class="hlist"><ul><li>Lists</li><li>Related</li></ul></div></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Glossary_of_botanical_terms" title="Glossary of botanical terms">Botanical terms</a></li>

<li><a href="List_of_botanists" title="List of botanists">Botanists</a>

<ul><li><a href="List_of_botanists_by_author_abbreviation_(W%E2%80%93Z)" title="List of botanists by author abbreviation (W–Z)">by author abbreviation</a></li></ul></li>

<li><a href="Botanical_expeditions" title="Botanical expeditions">Botanical expeditions</a></li>

<li><a href="List_of_individual_trees" title="List of individual trees">Individual trees</a></li>

<li><a href="List_of_oldest_trees" title="List of oldest trees">Oldest trees</a></li>

<li><a href="List_of_superlative_trees" title="List of superlative trees">Superlative trees</a></li>

<li><a href="List_of_tallest_trees" title="List of tallest trees">Tallest trees</a></li>

<li><a href="Lists_of_plants" title="Lists of plants">Plants</a></li></ul>

</div></td></tr><tr><td class="navbox-abovebelow" colspan="2" style="background: #C3EEC3;"><div>

<ul><li><span class="noviewer" typeof="mw:File"><span title="Category"></span></span> Category</li></ul>

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This article is issued from <a class="external text" title="Last edited on 2025-06-19" href="https://en.wikipedia.org/wiki/?title=Double_fertilization&oldid=1296408134">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

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