Orobanche

Broomrapes are generally small, only tall depending on species. They are best recognized by the yellow- to straw-coloured stems completely lacking chlorophyll, bearing yellow, white, or blue snapdragon-like flowers. The flower shoots are scaly, with a dense terminal spike of 10-20 flowers in most species, although single in one-flowered broomrape (Orobanche uniflora). The leaves are merely triangular scales. The seeds are minute, tan or brown, blackening with age. These plants generally flower from late winter to late spring. When they are not flowering, no part of the plants is visible above the surface of the soil. ==Parasitism==

As they have no chlorophyll, the broomrapes are totally dependent on other plants for nutrients. Broomrape seeds remain dormant in the soil, often for many years, until stimulated to germinate by certain compounds produced by living plant roots. Broomrape seedlings put out a root-like growth, which attaches to the roots of nearby hosts. Once attached to a host, the broomrape robs its host of water and nutrients. Some species are only able to parasitise a single plant species, and they are often named after the plant they parasitise, such as ivy broomrape (O. hederae) being restricted to parasitising ivy. Others can infect several genera, such as the lesser broomrape O. minor, which lives on clover and other related Fabaceae. Branched broomrape (Orobanche ramosa), native to central and southwestern Europe but widely naturalised elsewhere, is considered a major threat to crops in some areas. Plants that it targets are tomato, eggplant, potato, cabbage, coleus, bell pepper, sunflower, celery, and beans. In heavily infested areas, branched broomrape can cause total crop failure. The bean broomrape (Orobanche crenata), which parasitizes the fava bean, has stems that are gathered and eaten in the Italian region of Apulia. ==Etymology==

The generic name Orobanche comes from the Greek (), from ( "bitter vetch") + ( (I) "strangle"). The common name "broomrape" comes from the English "broom" (a plant) + Latin ('tuber'). ==Species==

The following species are recognised in the genus Orobanche: • Orobanche aconiti-lycoctoni • Orobanche aegyptiaca — Egyptian broomrape; Fenzhi broomrape • Orobanche alba — Thyme broomrape; baihua broomrape • Orobanche alsatica — Alsace broomrape; Duose broomrape • Orobanche amethystea — Eryngium broomrape • Orobanche amoena • Orobanche anatolica • Orobanche androssovii • Orobanche angustelaciniata • Orobanche apuana • Orobanche arenaria — Wormwood broomrape • Orobanche arizonica • Orobanche armena • Orobanche arpica • Orobanche artemisiae-campestris • Orobanche astragali • Orobanche auranitica • Orobanche australiana • Orobanche australis • Orobanche ballii • Orobanche ballotae • Orobanche balsensis • Orobanche bartlingii • Orobanche baumanniorum • Orobanche beauverdii • Orobanche benkertii • Orobanche boninsimae • Orobanche borissovae • Orobanche brachypoda • Orobanche brassicae • Orobanche bulbosa • Orobanche bungeana • Orobanche caesia • Orobanche calendulae • Orobanche californica • Orobanche campanulae • Orobanche camphorosmae • Orobanche camptolepis • Orobanche canescens • Orobanche caryophyllacea — Bedstraw broomrape; Simao broomstraw • Orobanche castellana • Orobanche cathae • Orobanche caucasica • Orobanche centaurina • Orobanche cernua — Nodding broomrape; Wanguan broomrape • Orobanche chilensis • Orobanche chironii • Orobanche chrysacanthi • Orobanche cilicica • Orobanche cistanchoides • Orobanche clarkei — Xizang broomrape • Orobanche clausonis • Orobanche coelestis — Changchi broomrape • Orobanche coerulescens • Orobanche cohenii • Orobanche connata • Orobanche cooperi — Cooper's broomrape • Orobanche corymbosa — Flat-top broomrape • Orobanche crenata — Bean broomrape • Orobanche cumana • Orobanche cypria • Orobanche cyrenaica • Orobanche cyrnea • Orobanche dalmatica • Orobanche daninii • Orobanche densiflora • Orobanche denudata • Orobanche dhofarensis • Orobanche ducellieri • Orobanche dugesii • Orobanche ebuli • Orobanche elatior — Knapweed broomrape; Duanchun broomrape • Orobanche eriophora • Orobanche esulae • Orobanche fasciculata — Cluster broomrape; fascicled broomrape • Orobanche flava — Butterbur broomrape • Orobanche foetida • Orobanche fuscovinosa • Orobanche gamosepala • Orobanche georgii-reuteri • Orobanche gigantea • Orobanche glabricaulis • Orobanche gracilis — Slender broomrape • Orobanche gratiosa • Orobanche grenieri • Orobanche grisebachii • Orobanche grossheimii • Orobanche gussoneana • Orobanche hadroantha • Orobanche haenseleri • Orobanche hansii • Orobanche hederae – Ivy broomrape • Orobanche hedypnoidis • Orobanche heldreichii • Orobanche hirtiflora • Orobanche humbertii • Orobanche hymenocalyx • Orobanche hypertomentosa • Orobanche iammonensis • Orobanche iberica • Orobanche inexspectata • Orobanche ingens • Orobanche inulae • Orobanche javakhetica • Orobanche kashmirica • Orobanche kelleri — Duanchi broomrape • Orobanche kotschyi — Yitong broomrape • Orobanche krylowii — Siduomao broomrape • Orobanche kurdica • Orobanche lainzii • Orobanche laserpitii-sileris • Orobanche latisquama • Orobanche lavandulacea • Orobanche laxissima • Orobanche leptantha • Orobanche libanotica • Orobanche litorea • Orobanche longibracteata • Orobanche loscosii • Orobanche lucorum — Barberry Broomrape • Orobanche ludoviciana — Prairie broomrape; desert broomrape • Orobanche lutea — Medick broomrape • Orobanche lycoctoni • Orobanche megalantha — Dahua broomrape • Orobanche minor — Common broomrape; clover broomrape; lesser broomrape; small broomrape • Orobanche mlokosiewiczii • Orobanche mongolica — Zhonghua broomrape • Orobanche montserratii • Orobanche multiflora • Orobanche mupinensis — Baoxing broomrape • Orobanche muteliformis • Orobanche mutelii • Orobanche nana • Orobanche nowackiana • Orobanche olbiensis • Orobanche ombrochares — Maoyao broomrape • Orobanche orientalis • Orobanche owerinii • Orobanche oxyloba • Orobanche palaestina • Orobanche pancicii • Orobanche parishii • Orobanche penduliflora • Orobanche perangustata • Orobanche persica • Orobanche picridis-hieracioidis — Oxtongue broomrape • Orobanche pinorum • Orobanche portoilicitana • Orobanche psila • Orobanche pubescens — Hairy broomrape • Orobanche pulchella • Orobanche purpurea — Yarrow broomrape • Orobanche pycnostachya — Huanghua broomrape • Orobanche ramosa — Branched broomrape; hemp broomrape • Orobanche rapum-genistae — Greater broomrape • Orobanche rechingeri • Orobanche resedarum • Orobanche reticulata — Thistle broomrape • Orobanche reuteriana • Orobanche rigens • Orobanche riparia • Orobanche robbinsii • Orobanche rosmarina • Orobanche salviae • Orobanche sanguinea • Orobanche santolinae • Orobanche schelkovnikovii • Orobanche schultzii • Orobanche schweinfurthii • Orobanche septemloba • Orobanche serbica • Orobanche serratocalyx • Orobanche sinensis — Sichuan broomrape • Orobanche singarensis • Orobanche sintenisii • Orobanche solenanthi • Orobanche sordida — Danhuang broomrape • Orobanche spectabilis • Orobanche staehelinae • Orobanche stocksii • Orobanche subbaetica • Orobanche sulphurea • Orobanche tacnaensis • Orobanche tarapacana • Orobanche tetuanensis • Orobanche teucrii — Germander broomrape • Orobanche transcaucasica • Orobanche trichocalyx • Orobanche tricholoba • Orobanche turcica • Orobanche uniflora — Naked broomrape; one-flower cancer-root • Orobanche uralensis — Duochi broomrape • Orobanche valida • Orobanche vallicola • Orobanche variegata • Orobanche weberbaueri • Orobanche yuennanensis — Dianlie Broomrape • Orobanche zajaciorum • Orobanche zosimii ==References==