Adaptability of Soybeans to Late-Planted Environments (Isolines, Gxe, Double Cropping)
Raymer, Paul Lindell
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/71607
Description
Title
Adaptability of Soybeans to Late-Planted Environments (Isolines, Gxe, Double Cropping)
Author(s)
Raymer, Paul Lindell
Issue Date
1984
Department of Study
Agronomy
Discipline
Agronomy
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Agriculture, Agronomy
Abstract
Soybeans {Glycine max (L.) Merr.} are grown in the Midwest primarily as a full-season crop and only to a limited extent as a double crop. Development of cultivars specifically adapted to double cropping has been suggested as a means to expand double-crop acreage in this area. Before initiating a separate breeding program for the development of Midwestern double-crop cultivars, information is needed concerning genotype by cropping system interactions, plant traits associated with high yield in double-crop environments, and sources of breeding lines possessing these adaptive traits.
Three studies were conducted in an attempt to obtain this information. Performance in conventional early environments was compared with performance in double-crop environments. Douple-cropping was simulated by late planting in a conventionally prepared seedbed.
In the first study, 16 cultivars currently in use in the Midwest were evaluated. No significant cultivar by planting date interactions were found for yield. All cultivars suffered substantial yield reductions when planted late and the extent of yield reduction was similar among all cultivars. The relationship of yield with various plant traits varied greatly among years and no differences in these relationships were observed between the planting dates.
In the second study, near-isogenic lines in 'Harosoy' and 'Clark' genetic backgrounds which possess genes controlling maturity, stem morphology, and resistance to downy mildew (Peronospora manshuria) were evaluated. The lines tested provided a very wide range of maturities and stem lengths, and produced wide differences in yield at both planting dates. Maturities of 96-101 days and medium plant size were found to be optimum in both planting dates.
The objective of the third study was to identify breeding lines for use in a Midwestern double-crop breeding program. Soybean introductions were screened for low yield reduction or high yield when planted late. A number of lines were identified which experienced slightly less yield reduction than the best cultivars did when planted late, but these lines were usually inferior in terms of actual yield when planted late.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
