Water Use and Grain Yield in Drought‐Tolerant Corn in the Texas High Plains

Abstract

Drought is an important factor limiting corn (Zea mays L.) yields in the Texas High Plains, and adoption of drought‐tolerant (DT) hybrids could be a management tool under water shortage. We conducted a 3‐yr field study to investigate yield, evapotranspiration (ET), and water use efficiency (WUE) in DT hybrids. One conventional (33D49) and 4 DT hybrids (P1151HR, P1324HR, P1498HR, and P1564HR) were grown at three water regimes (I100, I75, and I50, referring to 100, 75, and 50% ET requirement) and three planting densities (PD) (5.9, 7.4, and 8.4 plants m−2). Yield (13.56 Mg ha−1) and ET (719 mm) were the greatest at I100 but WUE (2.1 kg m−3) was the greatest at I75. Although DT hybrids did not always have greater yield and WUE than 33D49 at I100, hybrids P1151HR and P1564HR consistently had greater yield and WUE than 33D49 at I75 and I50. Compared to 33D49, P1151HR and P1564HR had 8.6 to 12.1% and 19.1% greater yield at I75 and I50, respectively. Correspondingly, WUE was 9.8 to 11.7% and 20.0% greater at I75 and I50, respectively. Greater PD resulted in greater yield and WUE at I100 and I75 but PD did not affect yield and WUE at I50. Yield and WUE in greater PD (8.4 plants m−2) were 6.3 to 8.3% greater than those in smaller PD (5.9 plants m−2). The results of this study demonstrated that proper selection of DT hybrids can increase corn yield and WUE under water‐limited conditions.

Deficit Irrigation Management of Maize in the High Plains Aquifer Region: A Review

“…The research projects in Texas were conducted at the U.S. Department of Agriculture (USDA)-Agricultural Research Service (ARS), Conservation and Production Research Laboratory in Bushland, Texas (Musick and Dusek 1980;Eck 1986;Howell et al 1995;Schneider and Howell 1998;Tolk et al 1999;Baumhardt et al 2013), the Texas A&M AgriLife Research Station near Etter, Texas (Hao et al 2015a, b), and at producer sites near Lubbock, Texas (TAWC 2015). The climate is semiarid at all three locations (Table 1).…”

“…The study was conducted in lysimeters packed with Pullman, Ulysses, and Amarillo soil series under a rainout shelter. Hao et al (2015a, b) evaluated grain yield and CWUE responses of a conventional maize hybrid and four "drought-tolerant" AQUAmax â hybrids (DuPont-Pioneer, Johnston, Iowa) to irrigation at 50%, 75%, and 100% of ET c , and three planting densities at Etter, Texas from 2011 to 2013 (Table 5). The irrigation amounts in 1994 were 25% and 75% of the long-term seasonal rainfall of 200 mm, whereas the irrigation amounts in 1995 were 60% and 100%.…”

Exceedance Probability of the Standardized Precipitation-Evapotranspiration Index in the Texas High Plains

“…is required based on the production functions presented by Hao et al [29]. To illu-Agricultural Sciences Figure 5.…”

“…These precipitation amounts were used to determine how much irrigation would be required to achieve total seasonal crop water use of 750 mm (30 in.) for grain corn, which would result in maximum yield based on regional production functions [29].…”

“…Whether physical or regulatory limitations, achieving a desired water amount may not be possible. To determine the effects of drought on these situations, yield was calculated based on the crop production function of a common grain corn variety grown in the Texas High Plains [29]; however, rather than meeting a total water threshold, the seasonal irrigation amount was held constant at 400 mm (16 in. ), which is a targeted regulatory limit desired by several groundwater conservation districts in the Texas High Plains [6] [7].…”