Identification of QTL and candidate genes for plant density tolerance in maize

The global population is growing and up to three billion people will be added to the population within the next 35 years. Meanwhile, the amount of arable land for agricultural production is expected to remain the same. This suggests that grain yields will need to increase on a per unit area basis if food security is to be realized for the planet. This can be done by increasing the number of plants grown per unit area while simultaneously maintaining per plant yield. This increase in plant density will cause interplant competition for nutrients, light, and water. The ability to tolerate the increased plant density will determine the plant’s ability to maintain per plant yield under conditions of increased competition. A connected population of 320 testcross hybrids was developed using lines that previously demonstrated tolerance to high plant densities for the objective of identifying quantitative trait loci (QTL) and candidate genes for plant density tolerance. Yield trials were grown at a high plant density of 116,140 plants ha-1 (47,000 plants per acre [ppA]), and planted in five environments over 2012 and 2013. Grain yield and a total of 33 agronomic and morphological traits were evaluated in these five environments. QTL mapping within the nine subpopulations revealed 246 QTL and genome wide association study (GWAS) identified 11 single nucleotide polymorphisms (SNPs) with significant trait associations. Positional and functional candidate genes were investigated and are discussed.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Crop Sciences

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Potts, Sarah

Contributors dc:contributor

• Bohn, Martin O.
• Below, Frederick E.
• Brown, Patrick J.
• Mumm, Rita H.

• Candidate gene
• Genome-wide association study (GWAS)
• Maize
• Plant density tolerance
• quantitative trait loci (QTL)

Statement dc:rights

• Copyright 2014 Sarah Potts

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/49814

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/49814