Cover Crop Identity Differently Affects Biomass Productivity as well as Nitrogen and Phosphorus Uptake of Maize (Zea mays L.) in Relation to Soil Type

Cover crop integration in agriculture rotation is associated to multiple agronomic and environmental benefits. However, the effect of cover crop identity on the following cash crop productivity and nutrient uptake is still uncertain, particularly in relation to soil types. We set up an experiment to test the effects of four different cover crop species (Indian mustard, lupine, field pea, and oat) on maize above- and belowground biomass as well as on nitrogen and phosphorus nutrition after incorporation of the cover crop litter in two soil types (clay and sandy soil). We observed that aboveground and belowground biomass of maize was always higher in sandy than clay soil likely due to better soil physical properties. On general, in clay soil, the presence of a preceding cover crop promoted or did not modify the aboveground and the belowground maize productivity compared to bare soil. On the other hand, in sandy soil, the decomposing litter of non-leguminous cover crops decreased maize aboveground productivity whereas any preceding cover crop decreased maize root biomass. The burial of leguminous litter significantly increased the N uptake by maize in both soil types. For what concerns the phosphorus uptake by maize, it appears that due to high phosphorus soil availability, the selected cover crops did not play a major role in improving P uptake, with the only exception of field pea. Our data show that leguminous cover crops improved the N status of maize particularly under conditions of low N fertilization rates.

Automated summary

Integration of cover crops in agriculture rotation has multiple agronomic and environmental benefits. The impact of cover crop identity on cash crop productivity and nutrient uptake is still uncertain, especially with regard to soil types. Our experiment shows that leguminous cover crops improved nitrogen uptake by maize, while the effect on phosphorus uptake was less significant. Sandy soil had higher above- and belowground biomass of maize compared to clay soil. Overall, the presence of a preceding cover crop promoted or did not modify maize productivity in clay soil, but decreased aboveground productivity in sandy soil.