Maize Phenotypes Research Articles

Molecular basis for the CAT-2 null phenotype in maize.

Previous reports have described several maize lines whose developmental patterns of catalase gene expression vary from the "typical" maize line, W64A. Among these variants are the lines A16 and A338, both found to be null for the CAT-2 protein. Identification of a third CAT-2 null line, designated A340, is described. RNA blots and S1 nuclease protection analysis indicate that all three CAT-2 null lines produce a similarly shortened Cat2 transcript. The molecular basis for this aberrant Cat2 transcript is discussed.

Yellow-Stripe Phenotype in Maize. I. Effects of ys1Locus on Uptake and Utilization of Iron

1. The yellow-stripe maize mutant (ys1) resembles maize plants grown on iron-deficient or low-iron media. Homozygous recessive ys1/ys1 plants have been shown to respond to various iron sources differently than do plants carrying at least one dominant allele at this locus. Normally green homozygous dominant (+/+) and heterozygous (+/ys1) plants are visually indistinguishable and appear to be members of a single population distinct from ys1/ys1. This investigation was planned to delimit the site of the lesion and to characterize processes associated with this locus. 2. Foliar tissues of plants of genotypes +/+, +/ys1, or ys1/ys1 metabolize either Fe++ or Fe+++ iron. 3. Plants with the ys1/ys1 genotype are visually indistinguishable from +/+ plants when grown in nutrient solutions containing 2 p.p.m. FeSO4 or Fe-HEDTA (iron chelate of trisodium N-hydroxy-ethylethylenediaminetriacetic acid) but display the yellow-stripe phenotype when supplied with iron as Fe-EDTA (ferric chelate of ethylenediaminetetraacetic...