Quantitative Trait Loci for Leaf Angle, Leaf Width, Leaf Length, and Plant Height in a maize (Zea mays L) B73 × Mo17 population


Morphological traits affecting the canopy architecture of maize (Zea mays L) in high density cultivation can affect productivity. To identify quantitative trait loci affecting some of these traits, including leaf angle, leaf width, leaf length, and plant height, I analyzed these traits in the intermated B73 × Mo17 recombinant inbred line population, IBM-94, a maize population that other researchers developed for genetic studies by the scientific community. I collected data for the traits in replicated trials of IBM-94 grown in 2007, 2008, and 2009 at Sioux Falls, SD, USA. Means ± standard errors were for leaf angle = 26 ± 2.6°, leaf width = 91.0 ± 2.95 mm, leaf length 764.6 ± 20.76 mm, plant height = 2231.3 ± 101.24 mm. There was significant (a = 0.01) genotypic variation for each trait. Herita¬bility for height = 74.5%, leaf width = 86.2%, leaf length = 85.3%, and leaf angle = 90.5%. Phenotype data were combined with genetic maps and molecular marker haplotypes from the Maize Genetics and Genomics Database to analyze for quantitative trait loci by composite interval mapping using PLABMQTL computer software. One to three quantitative trait loci with logarithm of odds equivalent to a = 0.05 were identified for each trait. Three quanti¬tative trait loci were identified for leaf angle on chromosomes 1, 5, and 9, two for leaf width on chromosomes 2 and 8, one for leaf length on chromosome 2, and one for plant height on chromosome 4. Regression models explained 27.1% of leaf angle, 25.0% of leaf width, 9.1% of leaf length, and 8.4% of plant height variation.


leaf angle; leaf width; leaf length; plant height; QTL

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