Record Details

Effects of irrigation frequency on yields of winter wheat

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Field Value
Title Effects of irrigation frequency on yields of winter wheat
Names Nakamura, Brian Clifford (creator)
English, Marshall J. (advisor)
Date Issued 1982-10-13 (iso8601)
Note Graduation date: 1983
Abstract Deliberately underirrigating a crop may yield economic
benefits. The optimal use of water by an irrigator
should be achieved under a deficit irrigation regime. It
is important to know how water deficits affect yields and
the interaction of the deficits with the scheduling of
irrigations.
A field experiment was conducted during the 1981 irrigation
season to investigate the effects of high and low
frequency deficit irrigation on yields of winter wheat.
Yield and water use data were used to construct three production
functions. The relationship between the level of
water use and the resulting yield were determined for three
irrigation frequency regimes. Field plots under daily
(high frequency), weekly (normal frequency), and stress
(reduced frequency) regimes were included in the field
experiment as well as two dryland production plots.
The relationships derived from this project were characterized
by a large degree of scatter in the results.
Highly favorable weather conditions offset the effects of
irrigation deficits on plant yields throughout the irrigation
season. At this time, a second year of data is in the
process of compilation.
The results of a regression analysis showed no statistically
significant difference in the water use-yield
relationships of the three irrigation frequency regimes.
The effect of frequency did not lead to any readily apparent
differences in the three production functions.
The efficiency of water use of the different irrigation
frequencies increases with decreasing amount of applied
water for the 1981 crop year. The most efficient treatment,
i.e., least water use per unit of yield, was the pre-plant
irrigated, dryfarmed plots. The density of the wheat, a
measure of crop quality also increased with decreased water
use in this experiment. The optimal irrigation treatment
(measured by production and quality) was the two-week
frequency set.
Genre Thesis/Dissertation
Topic Irrigation efficiency
Identifier http://hdl.handle.net/1957/21199

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