| Title: | Isolation and identification of Desmodium root exudates from drought tolerant species used as intercrops against Striga hermonthica |
| Author(s): | Hooper AM; Caulfield JC; Hao B; Pickett JA; Midega CAO; Khan ZR; |
| Address: | "Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK. Electronic address: tony.hooper@rothamsted.ac.uk. Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK. Electronic address: john.caulfield@rothamsted.ac.uk. Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK. Electronic address: bing.hao@rothamsted.ac.uk. Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK. Electronic address: john.pickett@rothamsted.ac.uk. International Centre of Insect Physiology and Ecology, P.O. Box 30772, Nairobi, Kenya. Electronic address: cmidega@icipe.org. International Centre of Insect Physiology and Ecology, P.O. Box 30772, Nairobi, Kenya. Electronic address: zkhan@icipe.org" |
| DOI: | 10.1016/j.phytochem.2015.06.026 |
| ISSN/ISBN: | 1873-3700 (Electronic) 0031-9422 (Print) 0031-9422 (Linking) |
| Abstract: | "Plants from the genus Desmodium, in particular D. uncinatum, are used on sub-Saharan small-holder farms as intercrops to inhibit parasitism of cereal crops by Striga hermonthica and Striga asiatica via an allelopathic mechanism. The search for Desmodium species which are adapted to more arid conditions, and which show resilience to increased drought stress, previously identified D. intortum, D. incanum and D. ramosissimum as potential drought tolerant intercrops. Their potential as intercrops was assessed for resource poor areas of rain-fed cereal production where drought conditions can persist through normal meteorological activity, or where drought may have increasing impact through climate change. The chemical composition of the root exudates were characterised and the whole exudate biological activity was shown to be active in pot experiments for inhibition of Striga parasitism on maize. Furthermore, rain fed plot experiments showed the drought tolerant Desmodium intercrops to be effective for Striga inhibition. This work demonstrates the allelopathic nature of the new drought tolerant intercrops through activity of root exudates and the major compounds seen in the exudates are characterised as being C-glycosylflavonoid. In young plants, the exudates show large qualitative differences but as the plants mature, there is a high degree of convergence of the C-glycosylflavonoid exudate chemical profile amongst active Desmodium intercrops that confers biological activity. This defines the material for examining the mechanism for Striga inhibition" |
| Keywords: | "Chromatography, High Pressure Liquid Crops, Agricultural Droughts Exudates and Transudates/*chemistry Fabaceae/chemistry Flavonoids/analysis/chemistry/isolation & purification Mass Spectrometry/methods Pheromones/*chemistry/isolation & purification/pharma;" |
| Notes: | "MedlineHooper, A M Caulfield, J C Hao, B Pickett, J A Midega, C A O Khan, Z R eng BB/E015794/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom BB/F003986/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom BB/H001700/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom BBS/E/C/00004945/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom Research Support, Non-U.S. Gov't England 2015/07/15 Phytochemistry. 2015 Sep; 117:380-387. doi: 10.1016/j.phytochem.2015.06.026. Epub 2015 Jul 8" |
