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

This Article Figures Only Full Text 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 Larson, S. R. Articles by Kellogg, E. A. Search for Related Content PubMed Articles by Larson, S. R. Articles by Kellogg, E. A. Agricola Articles by Larson, S. R. Articles by Kellogg, E. A. Related Collections Seed Quality Other Forage Crops Seed Production

CROP BREEDING & GENETICS

Genetic Dissection of Seed Production Traits and Identification of a Major-Effect Seed Retention QTL in Hybrid Leymus (Triticeae) Wildryes

^a USDA Agriculture Research Service, Forage and Range Research Laboratory, Utah State Univ., Logan, UT 84322-6300
^b Dep. of Biology, Univ. of Missouri-St. Louis, St. Louis, MO 63121

^* Corresponding author (Steve.Larson{at}ars.usda.gov).

Many native grasses display seed shattering and other seed production problems. Basin wildrye [Leymus cinereus (Scribn. & Merr.) Á. Löve] and creeping wildrye [L. triticoides (Buckley) Pilg.] are perennial Triticeae grasses native to western North America. In this study, variation in the number of florets per inflorescence, percent seed set, seed mass, seed shattering, and seed dormancy was measured in clonally replicated multiyear field evaluations of 164 progeny derived from a backcross between a creeping x basin wildrye hybrid and a true creeping wildrye tester. Genomewide quantitative trait locus (QTL) scans detected independent gene effects for all five traits and one pleiotropic QTL, located on Triticeae homeologous chromosome group 6, associated with major seed shattering (43.1% R², 26.9 log of odds likelihood ratio [LOD]) and seed dormancy (24.1% R², 10.6 LOD) effects. We hypothesize that a dominant basin wildrye gene creates an abscission that promotes seed disarticulation but hinders seed development and seed ripening in the creeping wildrye backcross family. Alignments of Leymus chromosome 6 expressed sequence tag markers to the rice (Oryza) genome reveal well-defined correspondence of Leymus wildrye and American wildrice (Zizania palustris L.) seed shatter QTLs.

Abbreviations: CM, Chapalote maize • EST, expressed sequence tag • LOD, log of odds likelihood ratio statistic • MQM, multiple-QTL model • QTL, quantitative trait locus • RFLP, restriction fragment length polymorphism • rMQM, restricted MQM • RP, Reventador maize