Screening Sorghum for Resistance to Striga Hermonthica (Del.) Benth

The root hemiparasitic weed Striga hermonthica is a serious constraint to grain production of economically important cereals in sub-Saharan Africa. Six cultivars of sorghum Abu sabien, were tested for resistance and tolerance to this root hemi-parasite by applying one of two levels of Striga infestation (2 and 4 mg/pot). Results indicated that Striga emergence infesting on roots of all cultivars, indicating that none exhibited a true resistance mechanism. However, cultivar, V6 sustained the lowest Striga emergence and no significant decrease in host biomass. Cultivar V3 exhibited the highest in height and biomass on infection indicating the operation of a tolerance mechanism. Under high infestation, one promising variety namely V6 constantly recorded low number of parasite plants and lowest Striga growth. Sorghum V3 sustained the highest plant growth although it has high Striga infestation. Mature plant resistance was also expressed by delay of parasite emergence and inhibition of its development, low reduction in sorghum growth and production (dry matter) in comparison with susceptible cultivars. Adoption of an integrated approach encompassing high yielding Striga resistant and/or tolerant cultivars may provide a cheap and easy to apply method for Striga control under low-input farming systems.