|Stone, Kenneth - Ken|
Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 10/18/2018
Publication Date: 12/4/2018
Citation: Stone, K.C., Sigua, G.C., Bauer, P.J. 2018. Grain sorghum irrigation in the US Eastern Coastal Plain using variable rate irrigation. In: Proceedings of 2018 Irrigation and Education Conference, December 3-7, 2018, Long Beach, California. p.1-10.
Technical Abstract: Grain sorghum is one of the top five cereal crops and an important grain crop throughout the world. It is generally considered more drought tolerant compared to other grain crops such as maize. Recently, in the US eastern Coastal Plain region, there was an emphasis on increasing regional grain production in which grain sorghum played an important role. The region’s soils have low water holding capacities that combined with high rainfall variability cause crops frequently to be exposed to water stress. In this research, an experiment was conducted to evaluate the yield response of two grain sorghum varieties at different supplemental irrigation levels and three nitrogen levels. During our 3-year study, seasonal rainfall was adequate to produce acceptable grain sorghum yields and ranged from 421, 365, and 357 mm in 2012, 2013, and 2014, respectively. These rainfall amounts were greater than the seasonal calculated crop evapotranspiration requirement, but supplemental irrigation was required to maintain soil water potential above -30 kPa. However, irrigation did not increase grain sorghum yields. Additionally, no significant differences were found in grain yield between the two sorghum varieties or for increasing nitrogen applications. Results from this study suggest that there would be little benefit for supplemental irrigation for sorghum production in the US eastern Coastal Plain.