|
|
||||||||
a USDA-ARS, Lincoln, NE 68583
b Univ. of Nebraska, Lincoln, NE 68583
* Corresponding author (jshanahan1{at}unl.edu)
Received for publication April 28, 2004. Maintaining current high yields of corn (Zea mays L.) grown in the USA poses an environmental threat due to continued overuse of water and N inputs. To reduce overreliance on inputs, future corn breeding efforts should focus on improving tolerance of corn to water and N stresses, utilizing appropriate tolerance mechanisms. The objective of this study was to identify appropriate mechanisms by characterizing agronomic responses of 12 hybrids from three different eras (B73 x Mo17 from 1970s and three early 1990s and eight late 1990s Pioneer brand hybrids) to varying water and N supply. This was done by growing the hybrids under deficit and adequate levels of water (one-half and full evapotranspiration) and N (0 and 200 kg ha1) in a field study and measuring yield and other agronomic variables. While hybrid eras didn't differ in response to varying water or N, individual hybrids varied in ability to maintain yield under water or N stress. For example, under deficit water, 3417 produced 27% more yield than 3162 while they yielded similarly under adequate water. Likewise, under deficit N, 34R07 produced 42% more grain yield than '33G27' while they yielded similarly under adequate N. Agronomic variables such as kernel number per unit area were highly correlated with grain yield (r = 0.98), indicating hybrid ability to maximize kernel number under varying water and N supply was critical to maximizing yield. Determining physiological mechanisms associated with ability to maintain kernel number under stress should be a high priority of breeding programs.
Abbreviations: NUE, nitrogen use efficiency
This article has been cited by other articles:
![]() |
S. C. Mason, D. Kathol, K. M. Eskridge, and T. D. Galusha Yield Increase Has Been More Rapid for Maize than for Grain Sorghum Crop Sci., July 1, 2008; 48(4): 1560 - 1568. [Abstract] [Full Text] [PDF] |
||||
![]() |
K.-I. Kim, D. E. Clay, C. G. Carlson, S. A. Clay, and T. Trooien Do Synergistic Relationships between Nitrogen and Water Influence the Ability of Corn to Use Nitrogen Derived from Fertilizer and Soil? Agron. J., May 7, 2008; 100(3): 551 - 556. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. A. Shapiro and C. S. Wortmann Corn Response to Nitrogen Rate, Row Spacing, and Plant Density in Eastern Nebraska Agron. J., April 11, 2006; 98(3): 529 - 535. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. M. O'Neill, J. F. Shanahan, and J. S. Schepers Use of Chlorophyll Fluorescence Assessments to Differentiate Corn Hybrid Response To Variable Water Conditions Crop Sci., February 1, 2006; 46(2): 681 - 687. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Crop Science | Vadose Zone Journal | |||
| Journal of Natural Resources and Life Sciences Education |
Soil Science Society of America Journal | ||||
| Journal of Plant Registrations | Journal of Environmental Quality |
The Plant Genome | |||