Alfalfa Establishment with Diverse Annual Ryegrass Cultivars

Abstract

AbstractThere is limited information on forage yield and nutritional value of binary mixtures of annual ryegrass (Lolium multiflorum Lam.) with forage legumes in the north‐central USA. A diverse set of annual ryegrass cultivars in binary mixtures with alfalfa (Medicago sativa L.) was evaluated for seeding‐year forage yield and nutritional value and for forage yield and alfalfa presence the year after seeding. Annual ryegrass cultivars differing in ploidy and maturity were sown at 215 seeds m−2 with alfalfa at two locations in Wisconsin in spring 1990 and 1991. As a control, alfalfa was also sown alone. Seeding‐year forage yields of ryegrass‐alfalfa mixtures ranged from 5.00 to 10.65 Mg ha−1 in 1990 and from 7.06 to 8.96 Mg ha−1 in 1991. Mixtures of alfalfa with earlymaturing ryegrass cultivars were higher in yield and fiber fractions (neutral‐ and acid‐detergent fiber) and lower in crude protein concentration than mixtures with late‐maturing ryegrass cultivars, with greater differences observed in 1990 than 1991. The ryegrass‐alfalfa mixtures usually were higher yielding but lower in forage nutritional value than alfalfa sown alone, with greater differences observed in 1990 than 1991. Alfalfa stands were reduced by ryegrass in one site‐year, where conditions favored vigorous ryegrass development over alfalfa seedling development. In the other three environments, alfalfa was successfully established with all ryegrass cultivars, but alfalfa yields the year after seeding were highest in plots established with early‐maturing diploid cultivars. The most suitable annual ryegrass companions for alfalfa establishment in the north‐central region are early‐maturing diploid cultivars.