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 HighWire Citing Articles via Google Scholar Google Scholar Articles by West, D. R. Articles by Thomas, M. A. Search for Related Content PubMed Articles by West, D. R. Articles by Thomas, M. A. Agricola Articles by West, D. R. Articles by Thomas, M. A.

A Comparison of Replicated S₁ per se vs. Reciprocal Full-Sib Index Selection in Corn. I. Indirect Response to Population Densities¹

Two cycles of S₁ per se selection have been completed in each of three corn (Zea mays L.) populations: Nebraska B Synthetic (NBS), Nebraska Stiff Stalk Synthetic (NSS), and improved Nebraska Krug variety (NKS). In addition, two cycles of reciprocal full-sib recurrent selection (RFS) have been completed between NBS and NSS and between NBS and NKS. Each selection scheme was replicated three times. Selection was based on an index (resulting in a calculated value of yield on standing plants) and on yield trials generally grown at 51,666 plants/ha. Response at 68,888 and 17,222 plants/ha (called here indirect density response) is reported in this study. Each replicate of each selection procedure was grown as an S₁ random mating (RM), or variety cross population. Index values of cycle 2 (C₂.) were increased 20% or more over C₀ in tests of bulked S₁ populatgons selected by S₁ per se performance while response to RFS selection varied from an increase of 9% in C₂ of NKS to a negative response of –10% in NBS. Significant selection x plant populaion density effects were found only in the random mating test of the NKS population. Response to S₁ per se selection was significantly greater than response to RFS selectlon in the NBS random mating population, but response to the two methods did not differ in NSS or NKS grown as random mating populations.

Index means of variety crosses of C₂ were approximately 12% above C₀ variety crosses and there were no differences between selection methods. The evaluation of selection response indicated that in the early cycles of selection, response to selection at one plant density will be unchanged when selection products are grown at other plant densities. Response to S₁ per se selection was greater than RFS selection response in bulk S₁ and RM evaluations, but the RFS and S₁ per se methods resulted in equal improvement of variety cross performance.

Key Words: Zea mays L. • Recurrent selection • Replicated selection • Selection index

² Former research assistant (now assistant professor, Dep. of Plant & Soil Science, Univ, of Tennessee, Knoxville); professor of agronomy; and research assistant (now Genetic Dep., North Carolina State University, Raleigh).

Received for publication March 21, 1979.

This article has been cited by other articles:

				W.K. Russell Registration of 14 Populations of Maize Developed from a Long-Term Replicated Selection Study Crop Sci., June 20, 2006; 46(4): 1824 - 1825. [Full Text] [PDF]