Thomas Marek, Qingwu Xue, Wenwei Xu, Jake Becker,
G.J. Michels, T.A. Howell, P. Gowda, S.H. Amosson,
Bridget Guerrero, P.D. Colaizzi and J.M. Sweeten
Controlled Protocol details:
• Up to 12 inches of pumped irrigation water only
• 3 commercial corn hybrids,
• 4 planting populations, (20, 24, 28, & 32K)
• Plots laid out with AMS system
• Strip till pre-fertilized with in-season fertilized
• A sponsored project by
the OAP, the NPGCD & the TCPB.
Daily corn ET demand in Etter, TX (2010-2012)
0.7
2010, 33 in
0.6
2011, 46 in
2012, 37 in
Daily ET (in)
0.5
0.4
0.3
0.2
0.1
0
4/12
5/2
5/22
6/11
7/1
7/21
8/10
8/30
9/19
10/9
Source: TXHPET
Network
2012 Soil Profile Water -12-200
Corn Production Function (Field data-heavy clay soil)
250
Corn Yield. bu/ac.
200
150
2010 NPRF Yield
2011 NPRF Yield
100
2012 NPRF Yield
50
0
10
15
20
25
Total Crop Water , in.
30
35
1. Drought based events are part of the rainfall probability
distribution f(x) and they do occur and can have significant
consequence on corn production levels,
2. Crop production f(x) s are key to understanding
production potentials and we greatly enhanced our current
function in terms of yield with this study,
3. Irrigation depth per application generally should be
increased to the point that application runoff either does
not occur or is minimal (in terms of applied water
advancing forward of the application device) to reduce soil
evaporation losses (but should be limited to depleted
water within the soil root zone profile),
4) Manage upper soil profile cracking to the degree
possible with irrigation applications and allow for
maximum opportunity regarding rapid infiltration
potential should large rainfall events occur,
5) Implement a delayed corn planting date to shift the
peak corn ET requirement and to take advantage of
reduced ET requirements typical in the early fall
period
• Often unrestricted early season plant growth occurs (2012)
…so need growth restriction
•
• Possible differing ways to address this:
…1) early season growth regulator(s) and/or
…2) select hybrid(s) that have a lower ear height
• …3) possible use of a shorter maturity variety
• …the answer(s) is/are not known.
Sunset at the NPRF, 2012