Influence of cover crops and tillage systems on nematode populations in a maize-cover crop intercrop

Abstract

Cropping systems affect the distribution/diversity of soil microorganisms, including soilborne pathogens. In order to examine the effect of the cropping systems on soil nematodes, maize (Zea mays) was intercropped with different cover crops [Glycine max (GM), Macrotyloma uniflorum (MU), Centrosema pascuorum (CP), Cucurbita maxima (CM) and a control experiment with no cover crop (NC)] under different tillage systems [no till, reduced tillage and conventional tillage] to evaluate the effect of the various treatments on nematode population. The treatments were arranged in a split-plot design with three replications each. Tillage was the main treatment while cover crops were applied to subtreatment. In all, nematodes belonging to twenty-two (22) plant parasitic nematode genera were identified. While most of the genera were identified on all the treatments, the interaction of tillage systems and cover crops had significant effect on the population of Xiphinema and Trichodorus only, showing the nullifying effect of some tillage practices on the other nematodes which were significant under crops as only treatments inter alia. This information could be used in nematode management when integrated management systems are being considered for such intercrop mixtures.

Keywords:

• cover crops
• tillage systems
• nematodes

Acknowledgements

We thank Mr. Ibrahim Mohammed of the Department of Soil Science for his assistance throughout the work and Mr. Donald Iyorchir of Nematology laboratory of Crop Protection Department for analysing the soil samples for nematode populations.