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

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Related articles in Crop Science Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Casler, M. D. Articles by Stendal, C. Search for Related Content PubMed Articles by Casler, M. D. Articles by Stendal, C. Agricola Articles by Casler, M. D. Articles by Stendal, C. Related Collections Other Forage Crops Crop Genetics

CROP BREEDING, GENETICS & CYTOLOGY

Heterosis and Inbreeding Depression for Forage Yield and Fiber Concentration in Smooth Bromegrass

^a USDA-ARS, U.S. Dairy Forage Research Center, 1925 Linden Dr. West, Madison, WI 53706-1108
^b Dep. of Agronomy, Univ. of Wisconsin, Madison, WI 53706-1597

^* Corresponding author (mdcasler{at}wisc.edu).

Voluntary intake is generally considered to be the single most important factor limiting animal performance on high-forage diets. Neutral detergent fiber (NDF) is the laboratory variable most closely associated with voluntary intake potential. However, selection for low NDF generally leads to reduced forage yield. The objectives of this study were to estimate the correlation between forage yield and NDF and to determine heterotic responses for both traits. Seven clones of smooth bromegrass (Bromus inermis Leyss.) were crossed in a diallel and four of the clones were self-pollinated to create S1 families. The seven parent clones showed considerable diversity, as measured by 329 random amplified polymorphic DNA (RAPD) markers, mostly related to their pedigrees. The phenotypic correlation between forage yield and NDF decreased across generations, from 0.86 for parents, to 0.63 for GCA effects, and 0.49 for the 21 cross means. The genotypic correlation between forage yield and NDF was reduced from 0.99 for parents to 0.71 for the 21 crosses. Forage yield heterosis effects averaged 14% with a range of –4 to 39%, with 15 of 21 values significantly different from zero. Midparent heterosis effects for NDF averaged –0.5% with a range of –3.1 to 2.6%, with seven of 21 values significantly different from zero. Midparent heterosis effects for forage yield and NDF had a moderate correlation of 0.44. The change in correlations across generations suggested that a part of the genetic correlation between forage yield and NDF is regulated by linkage.

Abbreviations: DM, dry matter • NDF, neutral detergent fiber • RAPD, random amplified polymorphic DNA

Related articles in Crop Science:

THIS ISSUE IN CROP SCIENCE

Crop Science 2005 45: xi. [Full Text]  

This article has been cited by other articles:

				M. D. Casler and E. C. Brummer Theoretical Expected Genetic Gains for Among-and-Within-Family Selection Methods in Perennial Forage Crops Crop Sci., May 1, 2008; 48(3): 890 - 902. [Abstract] [Full Text] [PDF]