The Interaction of Endosperm Genotype and Genetic Background. Part I. Differences in Chromatographic Profiles of Starches from Nonmutant and Mutant Endosperms

The effect of maize endosperm genotype and genetic background on variation of endosperm starch properties has been examined by gel filtration. Nonmutant, and single, double and triple mutant combinations of the endosperm genes amylose‐extender (ae), dull (du), sugary (su), and waxy (wx) in four maize inbred lines were compared. The major effects of endosperm genes on starch properties did not vary as a result of genetic background. Starches from wx endosperms contained no amylose. The mutants ae, du and su resulted in starches with increased amylose content. Genetic background did affect starch properties in predictable ways. For example, the production of amylose in mutant endosperms was higher in the dent inbred background, followed by the sweet corn inbreds. However, the production of low molecular weight amylopectin and intermediate polysaccharide fractions was greatest in a sweet corn inbred background, We conclude that the material included in this study will be valuable in future investigations designed to delineate the interaction of genetic background and endosperm genotype in starch biosynthesis and starch properties.