Location: Soil and Water Management ResearchTitle: Drought tolerant (DT) and non-DT corn production under center pivot irrigation in the Texas High Plains Author
Submitted to: Proceedings of the Central Plains Irrigation Conference
Publication Type: Proceedings
Publication Acceptance Date: 2/20/2018
Publication Date: 2/21/2018
Citation: O'Shaughnessy, S.A., Andrade, M.A., Colaizzi, P.D., Evett, S.R. 2018. Drought tolerant (DT) and non-DT corn production under center pivot irrigation in the Texas High Plains. In: Proceedings of the 30th Annual Central Plains Irrigation Conference, February 20-21, 2018, Colby, Kansas. p. 186-198.
Interpretive Summary: Corn is an important crop for cattle feed in the Texas High Plains, but it requires more water than most other irrigated crops in the region. Drought conditions, limited well capacities and the non-replenishing Ogallala Aquifer raise concern for water pumped for crop production. The use of drought tolerant crops could help limit the amount of water required to maximize yields, however little information is published on drought tolerant corn production functions. This paper presents irrigation amounts, grain yield, crop water use and grain yield water use efficiency for different corn hybrids grown in Bushland, Texas. With this information, farmers can consider the benefits and disadvantages of using short-season corn hybrids over mid- and full-season hybrids, as well as realize the potential for mid-season DT corn hybrids to produce high yields with some water savings as compared with more conventional hybrids.
Technical Abstract: Corn (Zea mays L.) for feed is an important crop in the Texas High Plains region. However, it requires more water than the other major crops grown in the area to maximize grain yields. Pumping water for agriculture from the declining Ogallala Aquifer is of concern and improving irrigation water use efficiency (IWUE) using drought tolerant (DT) corn is of major interest. However, information on the performance of DT corn is limited. This paper discusses cumulative irrigation amounts, grain yields, seasonal crop evapotranspiration (ETc) and water use efficiency for DT corn hybrids grown under various irrigation levels in Bushland, Texas over the past five years. A two-year study (2013-2014) demonstrated that a mid-season DT hybrid required less irrigation compared with a conventional (CONV) hybrid, however grain yields and WUE between the hybrids were similar. Two corn hybrids with the same DT rating and relative days of maturity five days apart, were planted late in June 2015. Cumulative irrigation amounts were within 1 in. for each hybrid when compared at the same irrigation level. There was a significant difference in grain yield and WUE between hybrids at the most deficit irrigation level. In 2016, crop response between mid-season and early-maturing DT hybrids planted 30 days apart demonstrated substantial savings in irrigation water for the early-maturing hybrid, however, grain yields were substantially reduced compared with the mid-season hybrid. Drought tolerant hybrids may be beneficial in reducing cumulative irrigation requirements, and improving WUE. Mid-season DT hybrids planted in May in this region are likely to produce grain yields with no yield penalties compared with CONV mid-and full-season hybrids.