Author
SCHLEGEL, ALAN - Kansas State University | |
ASSEFA, YARED - Kansas State University | |
O'BRIEN, DAN - Kansas State University Extension Center | |
LAMM, FREDDIE - Kansas State University Extension Center | |
HAAG, LUCAS - Kansas State University Extension Center | |
STONE, LLOYD - Kansas State University |
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 12/10/2015 Publication Date: 3/4/2016 Citation: Schlegel, A.J., Assefa, Y., O'Brien, D., Lamm, F.R., Haag, L.A., Stone, L.R. 2016. Comparison of corn, grain sorghum, soybean, and sunflower under limited irrigation. Agronomy Journal. 108(2):670-679. Interpretive Summary: As water availability from the Ogallala Aquifer decreases, farmers need management options that optimize returns from limited irrigation water. Scientists from Kansas State University in the ARS led Ogallala Aquifer Program compared the response of corn, sorghum, sunflowers and soybeans to variable rates of irrigation water. When only 5 inches of irrigation water are available, yields and returns from corn, sorghum, soybeans and sunflowers were comparable. With 10 to 15 inches of irrigation water, returns from corn were higher than other crops. These results are of interest to farmers and crop consultants in helping to deal with low irrigation capacities. Technical Abstract: Corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] constitute a large share of the annual total irrigated planted area in the central Great Plains. This study aimed to determine the effect of limited irrigation on grain yield, water use, and profitability of corn and soybean in comparison with two crops commonly grown in water-limited environments (grain sorghum [Sorghum bicolor (L.) Moench.] and sunflower [Helianthus annuus L.]). The study was conducted at Tribune, KS, from 2001 to 2008, with a mean April to October rainfall of 390mm. Treatments were a complete factorial of four crops and three irrigation levels: 127, 254, and 381mm. At all irrigation levels, the mean grain yield of corn was greater than that of grain sorghum, followed by soybean and sunflower. The grain yield of sorghum, soybean, and sunflower was 19%, 16%, and 33%, greater, respectively, at 254 mm than at 127 mm irrigation,but similar for the 254 and 381 mm irrigation levels. Corn grain yield was 49% greater with 254mm than with 127mm irrigation and increased by an additional 17% under 381mm irrigation. Available soil water in the 0 to 30cm soil depth at harvest was approximately 19 mm for corn and approximately 31 mm for sorghum. Under limited irrigation conditions (127 mm), we have concluded that producers have multiple crop choices (corn, sorghum, soybean, or sunflower) with small yield and economic differences and, at higher irrigation levels (254 and 381 mm), a relative yield and economic advantage for corn. |