Rajatawa

Striga, atau secara lokal dikenal dengan rajatawa adalah marga (genus) tumbuhan yang mencakup sekelompok gulma parasit tanaman pangan Dalam pustaka berbahasa Inggris dikenal sebagai witchweed atau witchers weed. Tumbuhan ini ditemukan di Afrika, Asia, dan Australia, terutama di kawasan beriklim tropis. Beberapa jenisnya merupakan organisme pengganggu tanaman yang serius karena tidak sekadar menjadi parasit tetapi juga menyebabkan penyakit tanaman pangan, terutama di kawasan pertanian savanna Afrika. Sebagai pengganggu, Striga telah menyebar pula ke benua Amerika. Striga merupakan tumbuhan yang sangat diawasi penyebarannya oleh jawatan-jawatan karantina di seluruh dunia.

Striga
Klasifikasi ilmiah
Kerajaan:	Plantae
Klad:	Tracheophyta
Klad:	Angiospermae
Klad:	Eudikotil
Klad:	Asterid
Ordo:	Lamiales
Famili:	Orobanchaceae
Genus:	Striga

Gangguan

Jagung, sorgum, dan tebu adalah tanaman yang paling sering terganggu oleh striga, bahkan dapat menimbulkan kerugian 100%, termasuk di Amerika Serikat. Di Afrika, striga menjadi salah satu pengganggu terpenting. Sekitar 40% lahan savanna Afrika yang dapat digarap terkena dampak striga, sehingga menyebabkan kerugian sampai 13 miliar dollar AS per tahun.^[1]

Beberapa jenis

Photo of a striga plant (witchweed)

Striga bilabiata

• Striga asiatica has a very wide geographic distribution, from Africa through southern and eastern Asia to Australia. Since the 1950s, it is also known from the United States. This introduction, likely a result of human activity, resulted in an infestation of corn (maize) across many counties in North and South Carolina. The United States Department of Agriculture and state agencies imposed a quarantine on this area to control its spread - a process that was apparently successful.
• Striga gesnerioides, cowpea witchweed, as its name implies, is a parasite of cowpea (Vigna unguiculata), which is not a grass, but a member of the legume family (Fabaceae or Leguminosae). This species was also accidentally introduced into Florida in the United States, where it was found parasitizing Indigofera hirsuta (hairy indigo, another legume).
• Striga hermonthica (purple witchweed) is also a parasite that affects grasses, particularly sorghum and pearl millet in sub-Saharan Africa (Senegal to Ethiopia, Democratic Republic of Congo and Tanzania, Angola, Namibia).
• Striga aequinoctialis West Africa
• Striga angolensis Angola
• Striga angustifolia East Africa, Asia, Indonesia
• Striga asiatica (Asiatic witchweed) Africa, Arabian peninsula, India, Burma, China, Indonesia, the Philippines, Malaysia, New Guinea, Australia (introduced?), USA (introduced)
• Striga aspera Africa
• Striga bilabiata Africa
• Striga brachycalyx Africa.
• Striga chrysantha Central Africa
• Striga dalzielii West Africa
• Striga elegans Angola, Malawi, South Africa, Zimbabwe
• Striga forbesii Africa, Madagascar
• Striga gastonii Chad, Central African Republic
• Striga gesnerioides (cowpea witchweed) Africa, Arabian peninsula, India, USA (introduced)
• Striga gracillima Tanzania
• Striga hallaei Gabon, Democratic Republic of Congo
• Striga hirsuta Madagascar
• Striga indica India
• Striga junodii South Africa, Mozambique
• Striga klingii West Africa, Nigeria, Ghana, Cameroon, Togo
• Striga latericea East Africa, Ethiopia, Somalia
• Striga lepidagathidis Senegal, Guinea, Guinea Bissau
• Striga lutea Sudan, Ethiopia
• Striga macrantha West Africa, Nigeria, Ivory Coast, Togo
• Striga passargei West and Central Africa, Arabian peninsula
• Striga pinnatifida Ethiopia
• Striga primuloides Ivory Coast, Nigeria
• Striga pubiflora Somalia
• Striga yemenica Ethiopia

Galeri

• 
  Striga densiflora in Hyderabad, India
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  Striga densiflora in Hyderabad
• 
  Striga densiflora in Hyderabad

Lihat pula

• Push–pull technology