HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Forsberg, R. A. Articles by Nishiyama, I. Search for Related Content PubMed Articles by Forsberg, R. A. Articles by Nishiyama, I. Agricola Articles by Forsberg, R. A. Articles by Nishiyama, I.

Instability for Crown Rust Reaction and Kernel Color in F₆ -F₁₀ Lines of a Derived-Tetraploid x Avena sativa Hybrid¹

Major genes governing dark kernel color and resistance to the crown rust fungus (Puccinia coronata Cda. f. sp. avenae Fraser & Led.) were linked in four F₆ lines from the oat cross derived-tetraploid C.I.7232 (2n-28) x Avena sativa L. var. ‘Clarion’ (2n=42). Most dark-resistant (D-R) plants were not true breeding; abnormal and irregular segregation ratios of D-R and light-susceptible (L-S) plants occurred in F₆-F₁₀ lines from D-R parents. L-S plants were highly self-fertile and bred true. Cytological investigations revealed aneuploid plants (2n=43) in which the D-R genes were carried on an extra chromosome and euploid plants (2n=42) in which the genes were in a closely paired bivalent. Differential gamete frequencies, certation, or nonviability of homozygous-resistant genotypes due to abnormal dosage effects could account for the distorted ratios obtained and for the absence of stable, resistant lines.

Key Words: Oats • Linkage • Gene transfer • Aneuploids • Meiotic behavior • Chromosome addition lines • Substitution lines

² Assistant Professor and former Visiting Professor of Agronomy, University of Wisconsin, Madison 53706. Financial assistance from the Quaker Oats Company and from the Wisconsin Alumni Research Foundation through the University Research Committee is gratefully acknowledged by the second author.

Received for publication March 24, 1969.