Rye grain response to nitrogen fertilizer and seeding rate

Cereal rye (Secale cereale L.) seed production is of increasing value in the United States, yet basic agronomic management practices specific to rye grain production have not been established. Field research trials were conducted near Tifton and Midville, GA, during the winter crop season of 2017-2018 to assess effects of seeding rate and spring-applied N fertilizer on rye grain production. Cereal rye (cultivar 'Wrens Abruzzi') was planted at four seeding rates (215, 323, 431, and 538 seed m(-2)) and top-dressed with four spring fertilizer N rates (0, 34, 67, and 101 kg N ha(-1)) in a randomized complete block design with four replications. At both sites, rye grain yield responses to added N were best described by linear-plateau regression models. The yield response was greater at Tifton (following corn [Zea mays L.]) than at Midville (following peanuts [Arachis hypogaea L.]), and yield plateaued at 44 and 67 kg N ha(-1), respectively. Lodging was increased 31% with the addition of N fertilizer at Midville and also increased quadratically with seeding rate, which presumably contributed to yield reductions at a higher seeding rate (431 seed m(-2)) across both sites. This work demonstrates the potential to optimize rye grain production with substantially lower seeding rates and fertilizer N inputs than those recommended for other rye end uses (i.e., forage or cover crop) or other winter cereal species.