Agronomic Responses of Wheat and Oat Cultivars Under Dual-Purpose and Grain Production Management Strategies

Dual-purpose (DP) crops diversify farm income, facilitating livestock and grain production. Dual-purpose wheat (Triticum aestivum L.), i.e., grazing or clipping herbage early in the season followed by grain harvest, is commonly used in the Great Plains of the United States of America (USA), but the use of DP crops, including oat (Avena sativa L.), in the southeastern USA is limited. This 2-year study assessed agronomic and nutritive value responses and grain production of one wheat (AGS 4023) and four oat (Brooks, Horizon 214, Horizon 306, and Horizon 578) cultivars under two management strategies (dual-purpose [DP, clipping for forage and subsequent grain harvest] or grain production [GP]. Treatments were arranged in a randomized complete block design with three replications. Seasonal forage accumulation ranged from 4140 to 5460 kg ha−1 yr−1 among cultivars. Greater concentration of NDF (p < 0.001) was observed in year 2 than in year 1 (46.3% vs. 40.9%, respectively), but cultivars did not differ. Crude protein concentration ranged from 18.6% to 21% among cultivars. Grain yield was greater for H578 than all other cultivars (7400 versus an average of 5100 kg DM ha−1). Grain yield reduction for DP ranged from 27 to 45% compared with GP. These results demonstrate the potential of selected cultivars (e.g., H578) for use as DP crops in the region. Recognizing some reduction in grain yield compared with GP, DP cropping increases flexibility for producers, facilitating the use of integrated crop-livestock systems that diversify income streams and enhance the circularity of agroecosystems.