Evaluation of Seed-Filling Period as an Indirect Selection Trait for Higher Yield and Its Relationship With Nitrogen Parameters in Soybean

Previous reports have shown that seed-filling period (SFP) and seed yield are positively related in soybean (Glycine max (L.) Merr.). Indirect selection for yield using SFP is effective if heritability of SFP is higher than that for yield, and genetic correlation between SFP and yield is high. Relative selection efficiency of gain (p) was computed to determine the merit of using SFP in indirect selection for yield. Soybean population 1 and 2 were derived from cross PI 398.881 x PI 398.763 and PI 416.750 x PI 407.721, respectively. Determinate soybean lines in population 1 had a high heritability for SFP $({\rm h}\sp2$ = 0.84), and a high genetic correlation between SFP and yield (r = 0.92). However, the low number of lines (13) used prevent making a general conclusion for SFP as an indirect selection trait. Indeterminate soybean lines in population 2 had a low heritability for SFP $({\rm h}\sp2$ = 0.37) and SFP showed no relationship with yield. The low p value for SFP in indeterminate lines suggested that SFP would not be an effective indirect selection trait for yield. In population 2, neither heritability for SFP nor genetic correlation between SFP and yield was computed because genotypic variance for SFP and covariance for SFP and yield were negative. Phenotypic variance for SFP in population 2 was small.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Agronomy

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Auyeung, Man Ting

• Agriculture, Agronomy

Identifier

(UMI)AAI8721578

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/71633