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 Moll, R. H. Search for Related Content PubMed Articles by Moll, R. H. Agricola Articles by Moll, R. H.

Sixteen Cycles of Recurrent Full-Sib Family Selection for Grain Weight in Two Maize Populations

Dep. of Genetics, Box 7614, North Carolina State Univ., Raleigh, NC 27695-7614

^* Corresponding author.

Full-sib family selection for greater grain weight per plant is expected to increase the frequency of favorable alleles for this trait in random-mating populations of maize (Zea mays L.). This study was undertaken to assess responses to selection and changes in genetic variances accumulated during 16 cycles in (i) the open-pollinated population Jarvis Golden Prolific, and (ii) the population descended from the F₂ generation of the single cross NC7 x CI21. Selection responses were measured in replicated experiments that included Cycle 0 and several advanced selection cycles, and by estimates of accumulated gains through all 16 cycles of the selection experiments per se. In addition to increases in mean grain weight, changes in responsiveness to environmental effects were evaluated by regression analysis. The selection experiments were designed to provide estimates of genetic variances from progeny test data of each selection cycle. Gains due to selection were linear for 16 cycles at a rate of 2.4% cycle^–1 for the Jarvis population and 4.5% cycle^–1 for the NC7 x CI21 population. Advanced selection cycles were more responsive to environments than the original populations. Additive genetic variance showed no trend associated with selection in the Jarvis population, but declined with selection in the NC7 x CI21 population. Accumulated gains were greater in the NC7 x CI21 population, even though the genetic variance in that population was smaller initially and has decreased in later selection cycles.

Received for publication August 3, 1990.