Host range studies of Fusarium oxysporum f.sp. strigae meant for the biological control of Striga hermonthica on maize and sorghum

Abstract

Fusarium oxysporum f.sp. strigae was reported to be effective in the control of Striga hermonthica (Del.). The most effective (pathogenic to Striga) isolates were PSM197 and FOXY2 obtained from Nigeria and Ghana, respectively. To make application easier, the organisms were encapsulated in a pesta as carriers. In order to determine the applicability of these bio-control agents, there is the need to evaluate its host range on cultivated crops. Therefore, 26 economically important crops in Nigeria were used in a screen house host range study using the two isolates as a granular formulation (pesta) applied in the planting holes before sowing/planting. Data on plant vigour, plant height, plant fresh and dry weight were taken and analysed using analysis of variance and means were separated using least significance difference. The result showed that 10 crops out of the 26 used in the study statistically differed with respect to plant height; eight crops statistically differed from the other crops in terms of plant vigour while five crops and seven crops differed statistically from the others in terms of fresh and dry weight, respectively. Some of the crops also showed symptoms of infection and this lead to further analysis in the laboratory.

Keywords:

• host range
• Striga hermonthica
• Fusarium oxysporum
• bio-control