Witchweeds (Striga spp.) are important root parasites of many cereal and legume crops in savanna and Sahelian regions of Africa. Evidence on the possible role of soil pathogenic bacteria and fungi in Striga control has been obtained. Here, the authors report that arbuscular mycorrhizal (AM) fungi can also affect the interaction between Striga and cereals. AM fungi negatively impacted on Striga seed germination, reduced the number of Striga seedlings attaching and emerging, and delayed the emergence time of Striga both in pot and field experiments. AM fungi enhanced the performance of the cereal host, allowing it to withstand Striga damage better. Management strategies for AM fungi for Striga control as part of an integrated management system are discussed.
AhmedN.SugimotoY.BabikerA. G. T.MohamedO. E.MaY.InanagaS., and NakajimaH. (2001), ‘Effects of Fusarium solani isolates and metabolites on Striga germination’, Weed Science, Vol 49, pp 354–358.
2.
AkiyamaK.MatsuzakiK.-I., and HayashiH. (2005), ‘Plant sesquiterpenes induce hyphal branching in arbuscular mycorrhizal fungi’, Nature, Vol 435, pp 824–827.
3.
BebawiF. F.EpleeR. E.HarrisC. E., and NorrisR. S. (1984), ‘Longevity of witchweed (Striga asiatica) seed’, Weed Science, Vol 32, pp 494–507.
4.
BernerD. K.CarskyR. J.DashiellK.KlingJ., and ManyongV. (1996), ‘A land management based approach to integrated Striga hermonthica control in Sub-Saharan Africa’, Outlook on Agriculture, Vol 25, pp 157–164.
5.
BudiS. W.Van TuinenD.MartinottiG., and GianinazziS. (1999), ‘Isolation from the Sorghum bicolor mycorrhizosphere of a bacterium compatible with arbuscular mycorrhiza development and antagonistic towards soilborne fungal pathogens', Applied and Environmental Microbiology, Vol 65, pp 5148–5150.
6.
CarskyR. J.BernerD. K.OyewoleB. D.DashiellK., and SchulzS. (2000), ‘Reduction of Striga hermonthica parasitism on maize using soybean rotation’, International Journal of Pest Management, Vol 46, pp 115–120.
7.
DoddJ. C. (2000), ‘The role of arbuscular mycorrhizal fungi in agro- and natural ecosystems’, Outlook on Agriculture, Vol 29, No 1, pp 55–62.
8.
GaurA., and AdholeyaA. (2002), ‘Arbuscular-mycorrhizal inoculation of five tropical fodder crops and inoculum production in marginal soil amended with organic matter’, Biology and Fertility of Soils, Vol 35, pp 214–218.
9.
GbèhounouG., and AdangoE. (2003), ‘Trap crops of Striga hermonthica: in vitro identification and effectiveness in situ’, Crop Protection, Vol 22, pp 395–404.
10.
GbèhounouG.AdangoE.HinviJ. C., and NonfonR. (2004), ‘Sowing date or transplanting as components for integrated Striga hermonthica control in grain-cereal crops?’Crop Protection, Vol 23, pp 379–386.
11.
GbèhounouG.PieterseA. H., and VerkleijJ. A. C. (2003), ‘Longevity of Striga seeds reconsidered: Results of a field study on purple witchweed (Striga hermonthica) in Benin’, Weed Science, Vol 51, pp 940–946.
12.
GossM. J., and De VarennesA. (2002), ‘Soil disturbance reduces the efficacy of mycorrhizal associations for early soybean growth and N2 fixation’, Soil Biology and Biochemistry, Vol 34, pp 1167–1173.
13.
GurneyA. L.PressM. C., and ScholesJ. D. (1999), ‘Infection time and density influence the response of sorghum to the parasitic angiosperm Striga hermonthica’, New Phytologist, Vol 143, pp 573–580.
14.
GworgworN. A., and WeberH. C. (2003), ‘Arbuscular mycorrhizal fungi–parasite–host interaction for control of Striga hermonthica (Del.) Benth. in sorghum [Sorghum bicolor (L.) Moench]’, Mycorrhiza, Vol 13, pp 277–281.
15.
HessD. E., and EjetaG. (1987), ‘Effect of cultural treatments on infestation of Striga hermonthica (Del.) Benth. (Scrophulariaceae) on sorghum in Niger’, in WeberH. C., and ForstreuterW., eds, Parasitic Flowering Plants. Proceedings of the 4th International Symposium on Parasitic Flowering Plants, Philipps-Universität, Marburg, Germany, pp. 367–375.
16.
KanampiuF.RansomJ.GresselJ.JewellD.FriesenD.GrimanelliD., and HoisingtonD. (2002), ‘Appropriateness of biotechnology to African agriculture: Striga and maize as paradigms', Plant Cell, Tissue and Organ Culture, Vol 69, pp 105–110.
17.
LendzemoV. W. (2004), ‘The tripartite interaction between sorghum, Striga hermonthica and arbuscular mycorrhizal fungi’, PhD thesis, Wageningen University, Wageningen.
18.
LendzemoV. W., and KuyperT. W. (2001), ‘Effects of arbuscular mycorrhizal fungi on damage by Striga hermonthica on two contrasting cultivars of sorghum, Sorghum bicolor’, Agriculture, Ecosystems and Environment, Vol 87, pp 29–35.
19.
LendzemoV. W.KuyperT. W.KropffM. J., and van AstA. (2005), ‘Field inoculation with arbuscular mycorrhizal fungi reduces Striga hermonthica performance on cereal crops and has the potential to contribute to integrated Striga management’, Field Crops Research, Vol 91, pp 51–61.
20.
LennéJ. (2000), ‘Pests and poverty: The continuing need for crop protection research’, Outlook on Agriculture, Vol 29, No 4, pp 235–250.
21.
MarleyP. S.AbaD. A.ShebayanJ. A. Y.MusaR., and SannisA. (2004), ‘Integrated management of Striga hermonthica in sorghum using a mycoherbicide and host plant resistance in the Nigerian Sudan-Sahelian savanna’, Weed Research, Vol 44, pp 157–162.
22.
McGonigleT. P.EvansD. G., and MillerM. H. (1990), ‘Effect of soil disturbance on mycorrhizal colonization and phosphorus absorption by maize in growth chamber and field experiments’, New Phytologist, Vol 116, pp 629–636.
23.
MichéL.BouillantM. L.RohrR.SalléG., and BallyR. (2000), ‘Physiological and cytological studies on the inhibition of Striga seed germination by the plant-growth promoting bacterium Azospirillum brasilense’, European Journal of Plant Pathology, Vol 106, pp 347–351.
24.
MillerM. H. (2000), ‘Arbuscular mycorrhizae and the phosphorus nutrition of maize: A review of Guelph studies’, Canadian Journal of Plant Science, Vol 80, pp 47–52.
25.
OlmsteadR. G. (2001), ‘Disintegration of the Scrophulariaceae’, American Journal of Botany, Vol 88, pp 348–361.
26.
OswaldA., and RansomJ. K. (2002), ‘Response of maize varieties to transplanting in Striga-infested fields', Weed Science, Vol 50, pp 392–396.
27.
OswaldA.RansomJ. K.KroschelJ., and SauerbornJ. (2001), ‘Transplanting maize and sorghum reduces Striga hermonthica damage’, Weed Science, Vol 49, pp 346–353.
28.
PageauK.SimierP.NauletN.RobinsR., and FerA. (1998), ‘Carbon dependency of the hemiparasite Striga hermonthica on Sorghum bicolor determined by carbon isotopic and gas exchange analyses', Australian Journal of Plant Physiology, Vol 25, pp 695–700.
29.
PressM. C. (1998), ‘Dracula or Robin Hood? A functional role for root hemiparasites in nutrient-poor ecosystems’, Oikos, Vol 82, pp 609–611.
30.
RankC.RasmussenL. S.JensenS. R.PierceS.PressM. C., and ScholesJ. D. (2004), ‘Cytotoxic constituents of Alectra and Striga species', Weed Research, Vol 44, pp 265–270.
31.
SalamiA. O., and OsonubiO. (2002), ‘Improving the traditional landuse system through agro-biotechnology: A case study of adoption of vesicular arbuscular mycorrhiza (VAM) by resource-poor farmers in Nigeria’, Technovation, Vol 22, pp 725–730.
32.
SamakéO. (2003), ‘Integrated crop management strategies in Sahelian land use systems to improve agricultural productivity and sustainability: a case study in Mali’, PhD thesis, Wageningen University, Wageningen.
33.
SauerbornJ.KranzB., and Mercer-QuiarshieH. (2003), ‘Organic amendments mitigate heterotrophic weed infestation in savannah agriculture’, Applied Soil Ecology, Vol 23, pp 1181–1186.
34.
SauerbornJ.SprichH., and Mercer-QuarshieH. (2000), ‘Crop rotation to improve agricultural production in Sub-Saharan Africa’, Journal of Agronomy and Crop Science, Vol 184, pp 67–72.
35.
SchulzS.HussainiM. A.KlingJ. G.BernerD. K., and IkieF. O. (2003), ‘Evaluation of integrated Striga hermonthica control technologies under farmer management’, Experimental Agriculture, Vol 39, pp 99–108.
36.
TothR.TothD.StarkeD., and SmithD. R. (1990), ‘Vesicular-arbuscular mycorrhizal colonization in Zea mays affected by breeding for resistance to fungal pathogens', Canadian Journal of Botany, Vol 68, pp 1039–1044.
37.
Van DelftG. J. (1997), ‘Root architecture in relation to avoidance of Striga hermonthica infection’, PhD thesis, University of York, UK.
38.
WatlingJ. R., and PressM. C. (2001), ‘Impacts of infection by parasitic angiosperms on host photosynthesis’, Plant Biology, Vol 3, pp 244–250.
