Maize Landraces are Less Affected byStriga hermonthicaRelative to Hybrids in Western Kenya

Abstract

Production of maize in western Kenya is severely constrained by the parasitic weed striga. Although productivity of maize can be improved through adoption of improved varieties, adoption of such varieties remains low in the region, as the majority of smallholder farmers still grow unimproved open-pollinated varieties (landraces). The performance of two improved hybrid varieties was evaluated against six landraces in striga-infested soils in western Kenya. The varieties were planted in plots under natural striga infestation and were supplemented with pot experiments under artificial infestation. Striga emergence was lower in landraces than in the hybrid varieties in both field and pot experiments. Similarly, height of maize plants at harvest and grain yields were higher in the landraces than in the hybrids. After three continuous cropping seasons, in all treatments, striga seedbank density increased two to seven times. Seedbank increase was higher with hybrids and two of the landraces, ‘Rachar' and ‘Endere'. These results provide an insight into the potential role landraces could play in efforts toward an integrated management approach for striga in smallholder cropping systems. They also highlight the need to develop hybrid maize lines with local adaptation to biotic constraints, specifically striga.