Irrigated corn production and management in the Texas High Plains

Authors: XUE, QINGWU - TEXAS A&M AGRILIFE; MAREK, THOMAS - TEXAS A&M AGRILIFE; XU, WENWEI - TEXAS A&M AGRILIFE; BELL, JOURDAN - TEXAS A&M AGRILIFE

Submitted to: Journal of Contemporary Water Research and Education
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/30/2017
Publication Date: 12/1/2017
Citation: Xue, Q., Marek, T., Xu, W., Bell, J. 2017. Irrigated corn production and management in the Texas High Plains. Journal of Contemporary Water Research and Education. 162(1):31-41. https://doi.org/10.1111/j.1936-704X.2017.03258.x.
DOI: https://doi.org/10.1111/j.1936-704X.2017.03258.x

Interpretive Summary: Corn is the major irrigated crop on the Texas High Plains (THP) using over 50% of the total irrigation water. Currently, high level corn production is challenged because of the declining water in the Ogallala Aquifer and water policies of regional groundwater conservation districts. However, mangement practices for sustainable high corn yields with less irrigation water need are to be refined. Scientists from Texas A&M University in the ARS led Ogallala Aquifer Program evaluated corn management practices on the THP with reduced or limited levels of irrigation over the last forty years. With recent advances in corn breeding and genetics, irrigation requirements can be reduced by up to 25% in some years with grain yields comparable to full irrigation. Among management practices, irrigation remains the single-most important factor affecting corn yields, with some effects from planting date, and seedlng rate.

Technical Abstract: Corn is the major irrigated crop in the Texas High Plains (THP) and uses 53% of the total agricultural regional water resource budget. Currently, the declining water level of the Ogallala Aquifer, coupled with irrigation pumping restrictions by regional groundwater conservation districts, is challenging sustainable, high level corn production. The objective of this article is to review production levels and evaluate corn management practices in the THP with reduced or limited levels of irrigation. Long-term field studies demonstrate that yield and water use efficiency (WUE) have increased significantly over the last forty years while seasonal corn evapotranspiration (ET) under full irrigation conditions has not increased. Among management practices, irrigation remains the single-most important factor in corn production. With recent advances in corn breeding and genetics, irrigation requirements can be reduced by up to 25% in some years and result in similar yields as compared to irrigation amounts at the 100% ET level. Also, WUE is generally maximized at irrigation levels meeting 75-80% ET demand. Newly developed drought tolerant corn hybrids have been shown to provide yield benefits of 10-15% under limited (reduced) irrigation water levels. At the higher irrigation levels (75-100% ET requirement), corn yield increased as seeding rate increased initially but did not increase further when the seeding rate exceeded 94,000 seeds per ha. Also, a multi-year planting date study indicated that high corn yields can still be achieved with a long-season hybrid when planted in the middle of May and early June. When the planting date is delayed to late June and early July, mid- and short- season hybrids showed a yield advantage over the long season hybrids.