ARS | Publication request: Tropical Vine Legume-Maize Mixtures for Enhanced Silage in Temperate Climates

Submitted to: International Symposium of Molecular Breeding of Forage Turf
Publication Type: Proceedings/Symposium
Publication Acceptance Date: February 16, 2005
Publication Date: July 1, 2005
Citation: Riday, H. 2005. Tropical vine legume-maize mixtures for enhanced silage in temperate climates. Proceedings of International Symposium of Molecular Breeding of Forage Turf. p. 123.

Technical Abstract: Maize silage (Zea mays) comprises an increasing proportion of US Midwestern dairy cow rations. A weakness of maize silage is its lower protein levels; however, maize silage protein and biomass yield might be enhanced by intercropping with legumes. This study examined forage quality and dry matter per hectare of tropical vine legumes intercropped with maize for silage in the temperate climate of Wisconsin, USA. At two Wisconsin, USA locations, in three replicates, five legume species-maize mixtures were grown: common bean (Phaseolus vulgaris), lablab, scarlet runner bean, sunn hemp (Crotalaria juncea), and velvet bean (Mucuna pruriens). Increased legume silage fractions resulted in increased crude protein but decreased maize grain. No significant differences were determined for total dry matter yields or NDF between these five mixtures and the pure maize control. Additionally, moisture levels were acceptable for ensiling. In most mixtures maize plants were able to support the legume vine; common bean was an exception. One week after pollen shed common bean vines reached the maize tassels and began to break them. One month after pollen shed common bean vine weight began to break the tops of maize stalks. In the common bean mixture, particularly, grain yield was lost to competition. Scarlet runner bean initially grew vigorously but was severely affected by white mold and potato leafhoppers (Empoasca fabae). After maize plants dried and the canopy opened, many legume species displayed renewed growth. Intercropping vine legumes with maize for enhanced silage is feasible. In future studies increasing legume density in intercropped silage mixtures may increase the legume fraction. Additionally, using lodge resistant corn varieties may allow increased legume support. In conjunction with this study, improved scarlet runner bean and lablab germplasm were selected for use in a temperate maize silage intercropping system.