Campus Units

Agronomy, Genetics

Document Type

Article

Publication Version

Published Version

Publication Date

2006

Journal or Book Title

Maydica

Volume

51

Issue

2

First Page

417

Last Page

423

Abstract

In order to determine how modern hybrids have impacted grain composition and amino acid content of the corn crop, we characterized a set of cultivars that were widely grown in different eras from the 1920s through 2001. Grain composition exhibited clear trends with time, with protein decreasing and starch increasing. The effects of different plant densities were examined. The grain protein content of modern hybrids responds to plant density and environment differently than the protein content of older varieties. These differences are consistent with a model in which protein content is modulated by different growth conditions. These differences may explain, in part, the mechanism by which modern hybrids maintain yield in different environments, i.e. reduction of protein content in stressful environments frees resources that are used to maintain yield. We examined the content of the nutritionally limiting essential amino acids lysine, methionine and tryptophan in grain of these cultivars. On a per tissue mass basis, the levels of these amino acids dropped with time while on a per protein basis, their levels were not significantly changed. We conclude that the development of modern hybrids has resulted in maize with reduced protein content, but the nutritional quality of this protein has not changed.

Comments

This article is from Maydica 51 (2006): 417.

Rights

Works produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted.

Language

en

File Format

application/pdf

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