Agriculture Reference
In-Depth Information
of the management operations described by
Tucker et al. (1987) have not changed substan-
tially, but signifi cant advances in wheat produc-
tion have emerged over the past 20 years.
Improved cultivars, more effi cacious herbicides
and fungicides, and better equipment are just a
few of the modern advances in wheat technology
brought about by public and private research.
Much of the improvement in wheat management
has resulted from understanding how these other
advances can be utilized together in a systems
approach to management. That is, the under-
standing of rudimentary agronomic components
of wheat production has not changed, but our
understanding of how these components interact
to form a profi table and sustainable management
system has changed appreciably.
Alley et al. (1993) eloquently showed how
the various components of wheat management
converge to determine fi nal grain yield. They
described yield as a function of kernels per head,
weight per kernel, and heads per unit area. Factors
such as cultivar selection, plant nutrition, and
precision planting are considered to be
yield
building factors
. Adjustments in these manage-
ment factors can actually improve the yield poten-
tial of the crop. Weed control, insect control,
disease control, lodging control, and harvest man-
agement are listed as
yield protecting factors
. These
yield protecting factors can only preserve inher-
ent yield potential of the crop; they cannot create
new yield potential. Arguably, the greatest
improvements in wheat yield at the farm level
over the past few decades emanated from better
understanding how yield building and yield pro-
tecting factors interact in a system.
Fig. 4.1
Average wheat yield has increased more rapidly in
soft red winter wheat production areas, such as Kentucky,
than in the US as a whole. Much of this increase can be
attributed to the introduction and implementation of
European-style intensive wheat management practices in the
1980s. (Adapted from National Agricultural Statistics Service,
2008.)
of management as summer crops. Introduction
of the intensive wheat management system in
the mid-1980s changed much of this mindset
(Snyder 2000). Producers in this region quickly
began to realize that wheat, like other crops,
was responsive to increased levels of inputs and
management. Since that time, average wheat
yields have increased much more rapidly in
the US Southeast than in the US as a whole
(Fig. 4.1).
Matching cultivar to environment
The basic concepts of intensive wheat manage-
ment center on matching cultivar with manage-
ment to create yield potential and protecting that
yield potential once it is established. In fact, some
have proposed that fi ne-tuning the matching of
management practices with cultivar selection
may have as much infl uence on yield as cultivar
improvement. Cooper et al. (2001), for example,
reported that much of the differential in grain
yield and grain protein that is attributed to
genotype
Intensive wheat management
An example of successful on-farm adoption of
a systems approach to wheat management is
the implementation of European-style intensive
wheat management in the soft red winter wheat
production areas of the US. Prior to introduction
of this system, wheat in the southeastern US had
largely been treated as a second-class crop that
did not receive the same attention and level
environment interactions in Australia
is actually better characterized by what they
described as genotype
×
management interac-
tions. Bell et al. (1995) attributed 28% of wheat
×
