Yield response of corn to deficit irrigation in a semiarid climate

Payero, J.O. and Melvin, S.R. and Irmak, S. and Tarkalson, D. (2006) Yield response of corn to deficit irrigation in a semiarid climate. Agricultural Water Management. 84:101-112.

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Abstract

Irrigation water supplies are decreasing in many areas of the US Great Plains, which is
requiring many farmers to consider deficit-irrigating corn (Zea mays L.) or growing crops like
winter wheat (Triticum aestivum L.) that require less water, but that are less profitable. The
objectives of this study were to: (1) quantify the yield response of corn to deficit irrigation,
and (2) determine which of several seasonal water variables correlated best to corn yield in a
semiarid climate. Eight (T1-T8) and nine (T1-T9) deficit-irrigated treatments (including
dryland), were compared in 2003 and 2004 in North Platte, Nebraska. The actual seasonal
crop evapotranspiration (ETd) (calculated with procedures in FAO-56) for the different
treatments was 37-79% in 2003 and 63-91% in 2004 compared with the seasonal crop
evapotranspiration when water is not limited (ETw). Quantitative relationships between
grain yield and several seasonal water variables were developed. Water variables included,
irrigation (I), total water (W ) rain + irrigation (WR+1), evaporation (E), crop evapotranspiration
(ETd) ; crop transpiration (Td), and the ratios of ETd and Td to evapotranspiration and
transpiration when water is not limited (ETw and Tw). Both years, yield increased linearly
with seasonal irrigation, but the relationship varied from year to year. Combining data from
both years, ETd had the best correlation to grain yield (yield = 0.028ETd-5.04; R2 = 0.95),
and the water variables could be ranked from higher to lower R 2 when related to grain
yield as: ET d(R2=0.95) > Td(R2=0.93) > ETd/ETw(R2=0.90) = Td/Tw(R2=0.90) > Wall(R2=0.89) > E(R2 =0.75) >
WR+I(R2=0.65) > I(R2=0.06). Crop water productivity (CWP) (yield per unit ETd) linearly increased
with ETd/ETW (R2 = 0.75), which suggests that trying to increase CWP by deficit-irrigating corn
is not a good strategy under the conditions of this study.

Item Type:	Article
NWISRL Publication Number:	1218
Subjects:	Irrigated crops > Corn / maize Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:49
Last Modified:	31 Oct 2016 17:24
Item ID:	56
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/56