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Irrigation Water Management Research
D.D. Steele, B.G. Schatz, T. Scherer, K. Grafton, J. Lorenzen,
C.W. Lee, A. Hla, P.E. Hendrickson, W.D. Larson, D.C. Hauf, D.C. Kirkpatrick,
and R. Chandel
A two-year study of irrigation water management practices
for potatoes, dry edible beans, and carrots was started in 1999. Field work was
conducted using a new, high-capacity center pivot irrigation system capable of
spatially-varied water applications. The objectives of the project were to: 1)
develop
fertility practices for appropriately-irrigated vegetable crops, 2) develop new
cultivars of dry edible beans that optimize production under irrigation, and 3)
develop evapotranspiration (ET) crop curves for representative cultivars of
vegetable crops, dry edible beans, and potatoes.
Six main plots were used to apply high and low irrigation
regimens for each of three replicates in each crop. The main plots or irrigation
zones ranged in size from approximately 40'x80' for beans to 50'x100' for
potatoes. Rain and irrigation amounts and soil moisture contents were
measured in each zone to estimate crop water use. Irrigations for each
zone were scheduled and applied independently from the schedules for the other
zones.
Smaller
plots, typically 10'x20' for beans and 12'x25' for potatoes, were used within
each main plot to test fertility management practices and crop varieties. For
the potatoes, the fertility treatments consisted of 14 combinations of nitrogen
fertilizer amounts, nitrogen timing methods, and phosphorus fertility amounts.
For the carrots, small-plot treatments consisted of combinations of four
nitrogen amounts, two nitrogen timing methods, two potassium fertilizer levels,
and two varieties. For the dry edible beans, two bean types and four nitrogen
fertility levels were compared. Results are summarized in Table 1. For more
information, see the website at http://www.ageng.ndsu.nodak.edu/crec/iwm_crec.htm.
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