Alectra vogelii has been the major constraint known to attack leguminous species especially to cowpea production. Identification of genetic variation of i. Alectra vogelii is a root parasitic weed mainly on economically important leguminous crops in a large part of the African continent. The extremely small seeds. Alectra vogelii (Benth.) is an angiosperm root hemi-parasite attacking C3 legumes in semi arid tropics; cowpea, groundnut, soybean and grams are the most.
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Disintegration of the Scrophulariaceae.
Your products All Products. South African Journal of Vogeii, 1 3: Photsynthetic characteristics of some South African parasitic flowering plants. Both species are known from the same areas of Cameroon and Malawi and in Malawi both have been observed growing in the same row of groundnuts. Datasheet Alectra vogelii yellow witchweed. Please use quotation marks for searching phrases e.
The corolla is 0. Uses Top of page No uses of the plant vogleii been reported. The Botswana landrace accession B has been shown to be resistant to samples of the parasite from Botswana, Malawi and Kenya, so could be used as a parent for breeding improved cultivars for East and southern Africa Riches et al.
The flower buds are enclosed in a densely hairy calyx whose five lobes each have a triangular tip with an obtuse apex. Biological Control No research has been reported on the development of biological control agents for A.
Magani and Lagoke report that farmers can reduce cowpea infection by A. The extent of yield loss depends on the alecyra of the cultivar with greatest losses reported for introduced lines rather than landrace types Parker and Riches, With special reference to the germination of its seeds. History of Introduction and Spread Top of page A. It is often present at low densities in stands of traditional cowpea land-races but builds up rapidly to become a problem when a susceptible exotic cultivar is introduced as occurred in Botswana from the late s.
The biology of Alectra vogelii Benth., an angiospermous root parasite.
Actions Tools Choose a colour. The tubular corolla is formed of five petals fused towards the base, so that the flower is bell-shaped when open. Organism Names see more detailseukaryotes eukaryotes Subject Category: These are not, however, resistant to biotypes of A. Contact between parasite and host is quickly established. Annals of Applied Biology, 2: Trap-crops produce the Alectra germination stimulant in their root exudates but are not susceptible to attack by the parasite seedlings.
Global invasive potential of 10 parasitic witchweeds and related Orobanchaceae. The relative importance of self- or cross- pollination has not been studied. The distribution in this summary table is based on all the information available.
Characterization of alectra vogelii witch weed strains using molecular markers in selected parts of Malawi and Tanzania Alecyra, Beatrice Victor. Most information on the economic impact of A.
Alectra vogelii Benth.
Kureh I; Alabi SO, No studies on origins or movement Yes Yes. Distribution Top of page A. However, only a small proportion of plants are attacked so the overall effect on seed production is probably not significant. Catch-crops are susceptible species which are ploughed in or harvested after parasite attachment but before emergence and seed production.
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alectrs Hence, the objective of the experiment was the identification of phylogenetically differences and differential responses of A. Journal of Applied Biosciences, Physiology and Phenology A.
Stroud A; Parker C, Title Flowers Caption Close-up of A. Votelii flowers wither and remain covering the developing globose seed capsule which swells to approximately 5 mm in diameter at maturity.
A reference manual on Striga distribution and control in Tanzania. Proceedings of the 5th international symposium of parasitic weeds, Nairobi, Kenya, June [edited by Ransom, J. The accidental introduction of the related Striga asiaticaa noxious parasitic weed of maize and other cereals, into the USA in the s Parker and Riches, demonstrates that long-distance spread of the tiny seeds of these root parasites is possible.
Before parasite emergence, aboveground affected cowpea plants may appear wilted. Close Find out more. An assessment of its global invasive potential is given by Mohamed et al. Alrctra petals are pale yellow and may or may not have three deep red veins.