Striga

Unidentified Stimulators. Growth-inhibitory materials in, or secreted by, plants have for the most part been emphasized in this paper. However, root secretions of many plants also contain constituents required for the germination of seeds of angiospermous root parasites (Striga, Orobanche, Alectra, and Sopubia genera). This phenomenon has been reviewed by Brown (17). Striga asiatica was identified for the first time in the western hemisphere in 1956 in two... 

Thiourea and allylthiourea (20), D-xylulose (22), sodium diethyldithiocarbamate, L-methionine, and -propyl-di- -propylthiol-carbamate (163), 12 6-(substituted) purines (166), and two coumarin derivatives (164) have been found to promote Striga seed germination. None of these materials, however, appear to be constituents of the natural stimulant preparations. 

Matusova, R. et ah, The strigolactone germination stimulants of the plant-parasitic Striga and Orobanche spp. are derived from the carotenoid pathway, Plant Physiol. 139, 920, 2005. 

Strigol is a natural product with unusually strong properties as a germination stimulant for parasitic weeds of the genera Striga (witchweed) and Orobanche (broomrape). 

Ramaiah, K. W. Parker, C. Vasudera Rao, M. J. Musselman, L. J. 1983. "Striga Identification and Control Handbook", Information Bulletin No. 15, Patancheru, A. P., India International Crops Research Institute for the Semi-Arid Tropics. 

Osman MA, Raju PS, Peacock JM (1991) The effect of soil temperature, moisture and nitrogen on Striga asiatica (L.) Kuntze seed germination, viability and emergence on sorghum (,Sorghum bicolor L. Moench) roots under field conditions. Plant Soil 131 265-273. doi 10.1007/BF00009458... 

Allelopathy found hopeful utilization in plant protection against parasite weeds. The main world parasitic species are the witchweeds (Striga spp.), broomrapes (Orobanche spp.), and eventually dodder (Cuscuta spp.). Witchweeds and broom-rapes attack many economically important crops especially throughout the semi-arid regions. Early detection of parasitic weed infestation and protection is difficult because of the growth habit of a root parasite and huge production of dust-like seeds viable up to 20 years (Kebreab and Murdoch 1999). 

Striga hermonthica Silverleaf (Desmodium intortum (Mill.) Urb.), greenleaf Trap crops between rows of Khan et al. 2002... 

Chang M, Netzly DH, Butler LG, LynnDG (1986) Chemical regulation of distance Characterization of the first natural host germination stimulant for Striga asiatica. J Am Chem Soc 108 7858-7860... 

Minorsky PV (2002) Allelopathy and grain crop production. Plant Physiol 130 1745-1746 Mloza-Banda HR, Kabambe VH (1997) Integrated management for striga control in Malawi. African Crop Sci J 5 263-273... 

Rao MR, Gacheru E (1998) Prospects of agroforestry Striga management. Agrofores Forum 9 22-27... 

Khan ZR, Pickett JA, Hassanah A, Hooper AM, Midega CAO (2008) Desmodium species and associated biochemical traits for controlhng Striga species present and future prospects. Weed Res 48 302-306... 

Figure 1. Electron Micrograph of the Developing Haustorium of Striga asiatica. (Courtesy of Dr. Vance Baird).

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