Yield, stalk, grain, and root characteristics of corn silage hybrids interseeded with alfalfa

Authors: Grabber, John

Submitted to: Laboratory Publication
Publication Type: Other
Publication Acceptance Date: 8/9/2024
Publication Date: 11/6/2024
Citation: Grabber, J.H. 2024. Yield, stalk, grain, and root characteristics of corn silage hybrids interseeded with alfalfa. Laboratory Publication. 1.

Interpretive Summary:

Technical Abstract: Interseeding alfalfa (Medicago sativa L.) into maize (Zea mays L.) provides production and environmental benefits, but the potential of this practice is limited by reduced dry matter yield of maize silage. A two-year trial in Wisconsin, USA quantified the impact of interseeding alfalfa immediately after maize planting on yield, shoot, and root charactersitics of 10 hybrids. Hybrids were either solo-seeded or interseeded in May, and soil moisture and shoot traits were assessed during growth. Maize was harvested in September and then root crowns were dug, photographed, and phenotyped. Silage, starch, and non-starch yields for solo-seeded maize were not affected by hybrid group or production year. Interseeding lowered yields by 18% and 27% in hybrid groups classified as having a small or large yield reduction response, and by 17% in 2021 and 29% in 2022 relative to solo-seeded maize. Interseeded maize had reduced canopy and grain development, a lower N nutrition index and chlorophyll content, and a shallower root system with fewer root tips than solo-seeded maize. Differences between cropping systems for shoot and root traits were more pronounced in 2022 when dry soil conditions restricted early-season growth of interseeded maize to a greater degree than solo-seeded maize. Hybrid group responses and regression analyses indicated silage yield was much more strongly related to shoot than to root traits.