Abstract
As a no-herbicide cropping system for silage soybean, we devised a new system using living mulch of Italian ryegrass. This study examined the effects of the living mulch on feed values of forage soybean in several treatments with seeding rates of Italian ryegrass and cultivation methods. Winter habit Italian ryegrass was sown in spring. After mowing of the first crop, it was used as living mulch for soybean. We cultivated soybean in this system for two years in two weed pollution treatments. The feed values of soybean were examined for forage samples collected during the second year of the experiment. Crude protein content rate in the living mulch treatments were higher than 20%, and were superior to those in the non-living mulch treatment. Fiber content rates were less in the living mulch treatment than in the non-living mulch treatment. TDN content rates and TDN yield of living mulch treatment were the same as those of the weeding treatment. Among the Italian ryegrass seeding rates, no differences were found in the crude protein content rate or fiber content rate. These results demonstrate that a feed value of soybean for silage cultivated with Italian ryegrass living mulch is sufficient as high-protein roughage.
