EFFECTS OF COMPETITION AND SELECTION PRESSURE ON YIELD RESPONSE IN WINTER RYE (SECALE CEREALE L.)
Abstract
AN UNSELECTED RYE POPULATION, WHICH WAS BULK PROPAGATED AT THE UNIVERSITY FARMFOR MORE THAN 20 YEARS, WAS PURPOSELY CHOSEN AS THE SELECTION MATERIAL. THE INVESTIGATION WAS CARRIED OUT AT THE UNIVERSITY FARM OF THESSALONIKI IN THE GROWING SEASONS 1981-82, 1982-83 AND 1983- 84 IN SEVEN EXPERIMENTS. THREE INTENSITIES 14.3%, 5.3% AND 1.6% OF MASS HONEYCOMB SELECTION APPLIED TO AN UNSELECTEDRYE POPULATION GAVE RESPECTIVELY AN ANNUAL YIELD RESPONSE OF 0.28, -3.69 AND-5.24% AT 15 CM SPACING, AND OF 4.07, 5.39 AND 8.99% AT 90 CM SPACING. THE NEGATIVE RESPONSE WITH COMPETITION WAS EXPLAINED BY STRONG NEGATIVE CORRELATION BETWEEN COMPETING AND YIELDING ABILITY WHICH CAUSES POSITIVE SKEWNESS BECAUSEOF TRANSPOSITION OF LOW YIELDERS AND STRONG COMPETITORS FROM THE LEFT TO THE RIGHT TAIL OF THE DISTRIBUTION. THE POSITIVE RESPONSE IN THE ABSENSE OF COMPETITION WAS MAINLY DUE TO THE INCREASED GENOTYPIC DIFFERENTIATION, WHICH ALLOWED EFFECTIVE DISCRIMINATION BETWEEN HIGH AND LOW YIELDING ...
show more
![]() | |
![]() | Download full text in PDF format (3.19 MB)
(Available only to registered users)
|
All items in National Archive of Phd theses are protected by copyright.
|
Usage statistics

VIEWS
Concern the unique Ph.D. Thesis' views for the period 07/2018 - 07/2023.
Source: Google Analytics.
Source: Google Analytics.

ONLINE READER
Concern the online reader's opening for the period 07/2018 - 07/2023.
Source: Google Analytics.
Source: Google Analytics.

DOWNLOADS
Concern all downloads of this Ph.D. Thesis' digital file.
Source: National Archive of Ph.D. Theses.
Source: National Archive of Ph.D. Theses.

USERS
Concern all registered users of National Archive of Ph.D. Theses who have interacted with this Ph.D. Thesis. Mostly, it concerns downloads.
Source: National Archive of Ph.D. Theses.
Source: National Archive of Ph.D. Theses.