View source for Striga ← Striga You do not have permission to edit this page, for the following reason: The action you have requested is limited to users in the group: Users. You can view and copy the source of this page. {{Treatment/ID |accepted_name=Striga |accepted_authority=Loureiro |publications={{Treatment/Publication |title=Fl. Cochinch. |place=1: 22. 1790 |year=1790 }} |common_names=Witchweed |special_status={{Treatment/ID/Special_status |code=I |label=Introduced }} |basionyms= |synonyms= |hierarchy=Orobanchaceae;Striga |hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Orobanchaceae]]</div><div class="higher-taxon"><small>genus</small>[[Striga]]</div></div> |etymology=Latin strigosus, slender, alluding to habit |volume=Volume 17 |mention_page=page 457 |treatment_page=page 508 }}<!-- --><span class="statement" id="st-d0_s0" data-properties=""><b>Herbs,</b> annual;</span> <span class="statement" id="st-d0_s1" data-properties="whole_organism duration;whole_organism architecture;whole_organism architecture;whole_organism nutrition;whole_organism nutrition;whole_organism growth form;haustorium quantity;haustorium size;haustorium quantity;haustorium size">chlorophyllous or achlorophyllous, hemiparasitic or holoparasitic, haustoria either single and relatively large, or multiple, smaller, and formed on secondary-roots.</span> <span class="statement" id="st-d0_s2" data-properties="stem orientation;stem texture;stem pubescence;stem pubescence;stem pubescence;stem pubescence;stem pubescence"><b>Stems </b>erect, sometimes fleshy, hispid, puberulent, or glabrous.</span> <span class="statement" id="st-d0_s3" data-properties="leaf position;leaf arrangement;leaf arrangement;leaf arrangement;leaf arrangement;leaf arrangement"><b>Leaves </b>cauline, opposite, subopposite, or alternate;</span> <span class="statement" id="st-d0_s4" data-properties="petiole presence">petiole absent;</span> <span class="statement" id="st-d0_s5" data-properties="blade texture;blade texture;margin architecture or shape">blade not fleshy, not leathery, margins entire.</span> <span class="statement" id="st-d0_s6" data-properties="inflorescence position or structure subtype"><b>Inflorescences </b>terminal, racemes or spikes;</span> <span class="statement" id="st-d0_s7" data-properties="bract presence">bracts present.</span> <span class="statement" id="st-d0_s8" data-properties="pedicel presence;pedicel presence"><b>Pedicels </b>present or absent;</span> <span class="statement" id="st-d0_s9" data-properties="bracteole presence">bracteoles present.</span> <span class="statement" id="st-d0_s10" data-properties="sepal atypical quantity;sepal quantity;calyx architecture or shape;calyx shape;lobe shape;lobe shape"><b>Flowers:</b> sepals 5 (–8), calyx radially or bilaterally symmetric, tubular, lobes lanceolate or subulate;</span> <span class="statement" id="st-d0_s11" data-properties="petal quantity;corolla coloration;corolla coloration;corolla coloration;corolla coloration;corolla coloration;corolla coloration;corolla coloration;corolla coloration;corolla coloration;corolla coloration;corolla coloration;corolla coloration;corolla coloration;corolla architecture;corolla shape;abaxial lobe quantity;adaxial lobe quantity">petals 5, corolla red, brownish red, or purple, rarely white or yellow, bilabiate, salverform, abaxial lobes 3, adaxial 2;</span> <span class="statement" id="st-d0_s12" data-properties="stamen quantity;stamen architecture;filament pubescence">stamens 4, didynamous, filaments glabrous;</span> <span class="statement" id="st-d0_s13" data-properties="staminode presence">staminode 0;</span> <span class="statement" id="st-d0_s14" data-properties="ovary architecture or structure in adjective form;ovary placentation">ovary 2-locular, placentation axile;</span> <span class="statement" id="st-d0_s15" data-properties="stigma architecture or shape">stigma capitate.</span> <span class="statement" id="st-d0_s16" data-properties="capsule dehiscence"><b>Capsules:</b> dehiscence loculicidal.</span> <span class="statement" id="st-d0_s17" data-properties="seed quantity;seed coloration;seed coloration;seed shape;wing presence"><b>Seeds </b>400–600, brown or black, ovoid, wings absent.</span><!-- -->{{Treatment/Body |distribution=s Asia;Africa;Australia |introduced=true |discussion=<p>Species ca. 40 (2 in the flora).</p><!-- --><p>Striga produces leaves of different sizes; typical proximal leaves are scalelike, and mid-stem leaves are larger. Striga is distinguished from its close relative Buchnera by its bilabiate corolla with an abruptly bent tube, one pollen sac, and glabrous filaments. Buchnera has a bilabiate corolla with a straight or slightly curved tube, two pollen sacs, and pilose filaments. Striga has been divided into three sections based on the number of ribs on the calyx tube (R. Wettstein 1891–1893): sect. Pentapleurae Wettstein with five, sect. Polypleurae Wettstein with ten, and sect. Tetrasepalum Engler with 15.</p><!-- --><p>Thirty-four species and subspecies of witchweeds occur in Africa; 22 are endemic (K. I. Mohamed et al. 2001). All Striga species parasitize hosts in the Poaceae except S. gesnerioides, which grows on hosts in Acanthaceae, Convolvulaceae, Euphorbiaceae, Fabaceae, and Solanaceae. Striga asiatica, S. aspera Bentham, S. forbesii Bentham, S. gesnerioides, and S. hermonthica (Delile) Bentham are of economic importance. Crops most affected by Striga include Digitaria exilis (fonio), Oryza subspp. (upland rice), Pennisetum glaucum (bulrush millet), Sorghum vulgare (sorghum), and Zea mays (maize). Striga gesnerioides is a serious pest on Vigna unguiculata (cowpea, Fabaceae) and a minor pest on other dicot crops. All species of witchweed are listed as noxious weeds by the United States Department of Agriculture and 11 state governments. New infestations of quarantine pests in the United States, such as witchweeds, should be reported to the State Plant Health Director in the appropriate state (http://www.aphis.usda.gov/services/report_pest_disease/report_pest_disease.shtml).</p> |tables= |references= }}<!-- --><div class="treatment-key"> ==Key== <div class="treatment-key-group"> {| class="wikitable fna-keytable" |-id=key-0-1 |1 |Calyx ribs 10; mid-stem leaf blades ascending or spreading, linear or narrowly elliptic, 20–50 mm; bracts linear, longer than calyces; corollas red, rarely yellow, with yellow throats; parasitic on Poaceae. |[[Striga asiatica|Striga asiatica]] |-id=key-0-1 |1 |Calyx ribs 5; mid-stem leaf blades appressed, lanceolate, 3–7 mm; bracts lanceolate, shorter than calyces; corollas brownish red or purple, rarely white; parasitic on dicots. |[[Striga gesnerioides|Striga gesnerioides]] |} </div></div><!-- -->{{#Taxon: name=Striga |author=Kamal I. Mohamed;Lytton J. Musselman |authority=Loureiro |rank=genus |parent rank=family |synonyms= |basionyms= |family=Orobanchaceae |illustrator=Barbara Alongi |illustration copyright=Flora of North America Association |distribution=s Asia;Africa;Australia |introduced=true |reference=None |publication title=Fl. Cochinch. |publication year=1790 |special status=Introduced |source xml=https://bibilujan@bitbucket.org/aafc-mbb/fna-fine-grained-xml.git/src/84153f6d59a0a91d69695978a64cee7560374f8e/V17/V17_878.xml |genus=Striga |abaxial lobe quantity=3 |adaxial lobe quantity=2 |blade texture=not leathery;not fleshy |bract presence=absent |bracteole presence=absent |calyx architecture or shape=symmetric |calyx shape=tubular |capsule dehiscence=loculicidal |corolla architecture=bilabiate |corolla coloration=yellow;white;purple;brownish red;yellow;white;purple;brownish red;yellow;white;purple;brownish red;red |corolla shape=salverform |filament pubescence=glabrous |haustorium quantity=multiple;single |haustorium size=smaller;large |inflorescence position or structure subtype=terminal |leaf arrangement=alternate;subopposite;alternate;subopposite;opposite |leaf position=cauline |lobe shape=subulate;lanceolate |margin architecture or shape=entire |ovary architecture or structure in adjective form=2-locular |ovary placentation=axile |pedicel presence=absent;absent |petal quantity=5 |petiole presence=absent |seed coloration=black;brown |seed quantity=400;600 |seed shape=ovoid |sepal atypical quantity=5;8 |sepal quantity=5 |stamen architecture=didynamous |stamen quantity=4 |staminode presence=absent |stem orientation=erect |stem pubescence=glabrous;puberulent;glabrous;puberulent;hispid |stem texture=fleshy |stigma architecture or shape=capitate |whole_organism architecture=achlorophyllous;chlorophyllous |whole_organism duration=annual |whole_organism growth form=herb |whole_organism nutrition=holoparasitic;hemiparasitic |wing presence=absent }}<!-- -->[[Category:Treatment]][[Category:Orobanchaceae]] Templates used on this page: Template:Orobanchaceae (view source) Template:Treatment/AuthorLink (view source) Template:Treatment/Body (view source) Template:Treatment/Body/Maps (view source) Template:Treatment/ID (view source) Template:Treatment/ID/Special status (view source) Template:Treatment/Publication (view source) Return to Striga.